Commit Graph

241 Commits

Author SHA1 Message Date
Andrey Konovalov
0fea6e9af8 kasan, arm64: expand CONFIG_KASAN checks
Some #ifdef CONFIG_KASAN checks are only relevant for software KASAN modes
(either related to shadow memory or compiler instrumentation).  Expand
those into CONFIG_KASAN_GENERIC || CONFIG_KASAN_SW_TAGS.

Link: https://lkml.kernel.org/r/e6971e432dbd72bb897ff14134ebb7e169bdcf0c.1606161801.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Marco Elver <elver@google.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-22 12:55:08 -08:00
Linus Torvalds
6a447b0e31 ARM:
* PSCI relay at EL2 when "protected KVM" is enabled
 * New exception injection code
 * Simplification of AArch32 system register handling
 * Fix PMU accesses when no PMU is enabled
 * Expose CSV3 on non-Meltdown hosts
 * Cache hierarchy discovery fixes
 * PV steal-time cleanups
 * Allow function pointers at EL2
 * Various host EL2 entry cleanups
 * Simplification of the EL2 vector allocation
 
 s390:
 * memcg accouting for s390 specific parts of kvm and gmap
 * selftest for diag318
 * new kvm_stat for when async_pf falls back to sync
 
 x86:
 * Tracepoints for the new pagetable code from 5.10
 * Catch VFIO and KVM irqfd events before userspace
 * Reporting dirty pages to userspace with a ring buffer
 * SEV-ES host support
 * Nested VMX support for wait-for-SIPI activity state
 * New feature flag (AVX512 FP16)
 * New system ioctl to report Hyper-V-compatible paravirtualization features
 
 Generic:
 * Selftest improvements
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "Much x86 work was pushed out to 5.12, but ARM more than made up for it.

  ARM:
   - PSCI relay at EL2 when "protected KVM" is enabled
   - New exception injection code
   - Simplification of AArch32 system register handling
   - Fix PMU accesses when no PMU is enabled
   - Expose CSV3 on non-Meltdown hosts
   - Cache hierarchy discovery fixes
   - PV steal-time cleanups
   - Allow function pointers at EL2
   - Various host EL2 entry cleanups
   - Simplification of the EL2 vector allocation

  s390:
   - memcg accouting for s390 specific parts of kvm and gmap
   - selftest for diag318
   - new kvm_stat for when async_pf falls back to sync

  x86:
   - Tracepoints for the new pagetable code from 5.10
   - Catch VFIO and KVM irqfd events before userspace
   - Reporting dirty pages to userspace with a ring buffer
   - SEV-ES host support
   - Nested VMX support for wait-for-SIPI activity state
   - New feature flag (AVX512 FP16)
   - New system ioctl to report Hyper-V-compatible paravirtualization features

  Generic:
   - Selftest improvements"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (171 commits)
  KVM: SVM: fix 32-bit compilation
  KVM: SVM: Add AP_JUMP_TABLE support in prep for AP booting
  KVM: SVM: Provide support to launch and run an SEV-ES guest
  KVM: SVM: Provide an updated VMRUN invocation for SEV-ES guests
  KVM: SVM: Provide support for SEV-ES vCPU loading
  KVM: SVM: Provide support for SEV-ES vCPU creation/loading
  KVM: SVM: Update ASID allocation to support SEV-ES guests
  KVM: SVM: Set the encryption mask for the SVM host save area
  KVM: SVM: Add NMI support for an SEV-ES guest
  KVM: SVM: Guest FPU state save/restore not needed for SEV-ES guest
  KVM: SVM: Do not report support for SMM for an SEV-ES guest
  KVM: x86: Update __get_sregs() / __set_sregs() to support SEV-ES
  KVM: SVM: Add support for CR8 write traps for an SEV-ES guest
  KVM: SVM: Add support for CR4 write traps for an SEV-ES guest
  KVM: SVM: Add support for CR0 write traps for an SEV-ES guest
  KVM: SVM: Add support for EFER write traps for an SEV-ES guest
  KVM: SVM: Support string IO operations for an SEV-ES guest
  KVM: SVM: Support MMIO for an SEV-ES guest
  KVM: SVM: Create trace events for VMGEXIT MSR protocol processing
  KVM: SVM: Create trace events for VMGEXIT processing
  ...
2020-12-20 10:44:05 -08:00
Catalin Marinas
e0f7a8d5e8 Merge branch 'for-next/uaccess' into for-next/core
* for-next/uaccess:
  : uaccess routines clean-up and set_fs() removal
  arm64: mark __system_matches_cap as __maybe_unused
  arm64: uaccess: remove vestigal UAO support
  arm64: uaccess: remove redundant PAN toggling
  arm64: uaccess: remove addr_limit_user_check()
  arm64: uaccess: remove set_fs()
  arm64: uaccess cleanup macro naming
  arm64: uaccess: split user/kernel routines
  arm64: uaccess: refactor __{get,put}_user
  arm64: uaccess: simplify __copy_user_flushcache()
  arm64: uaccess: rename privileged uaccess routines
  arm64: sdei: explicitly simulate PAN/UAO entry
  arm64: sdei: move uaccess logic to arch/arm64/
  arm64: head.S: always initialize PSTATE
  arm64: head.S: cleanup SCTLR_ELx initialization
  arm64: head.S: rename el2_setup -> init_kernel_el
  arm64: add C wrappers for SET_PSTATE_*()
  arm64: ensure ERET from kthread is illegal
2020-12-09 18:04:42 +00:00
Marc Zyngier
0cc519f85a KVM: arm64: Fix nVHE boot on VHE systems
Conflict resolution gone astray results in the kernel not booting
on VHE-capable HW when VHE support is disabled. Thankfully spotted
by David.

Reported-by: David Brazdil <dbrazdil@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
2020-12-08 19:51:49 +00:00
David Brazdil
78869f0f05 arm64: Extract parts of el2_setup into a macro
When a CPU is booted in EL2, the kernel checks for VHE support and
initializes the CPU core accordingly. For nVHE it also installs the stub
vectors and drops down to EL1.

Once KVM gains the ability to boot cores without going through the
kernel entry point, it will need to initialize the CPU the same way.
Extract the relevant bits of el2_setup into an init_el2_state macro
with an argument specifying whether to initialize for VHE or nVHE.

The following ifdefs are removed:
 * CONFIG_ARM_GIC_V3 - always selected on arm64
 * CONFIG_COMPAT - hstr_el2 can be set even without 32-bit support

No functional change intended. Size of el2_setup increased by
148 bytes due to duplication.

Signed-off-by: David Brazdil <dbrazdil@google.com>
[maz: reworked to fit the new PSTATE initial setup code]
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20201202184122.26046-9-dbrazdil@google.com
2020-12-04 10:07:12 +00:00
Mark Rutland
d87a8e65b5 arm64: head.S: always initialize PSTATE
As with SCTLR_ELx and other control registers, some PSTATE bits are
UNKNOWN out-of-reset, and we may not be able to rely on hardware or
firmware to initialize them to our liking prior to entry to the kernel,
e.g. in the primary/secondary boot paths and return from idle/suspend.

It would be more robust (and easier to reason about) if we consistently
initialized PSTATE to a default value, as we do with control registers.
This will ensure that the kernel is not adversely affected by bits it is
not aware of, e.g. when support for a feature such as PAN/UAO is
disabled.

This patch ensures that PSTATE is consistently initialized at boot time
via an ERET. This is not intended to relax the existing requirements
(e.g. DAIF bits must still be set prior to entering the kernel). For
features detected dynamically (which may require system-wide support),
it is still necessary to subsequently modify PSTATE.

As ERET is not always a Context Synchronization Event, an ISB is placed
before each exception return to ensure updates to control registers have
taken effect. This handles the kernel being entered with SCTLR_ELx.EOS
clear (or any future control bits being in an UNKNOWN state).

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20201113124937.20574-6-mark.rutland@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-12-02 19:44:03 +00:00
Mark Rutland
2ffac9e3fd arm64: head.S: cleanup SCTLR_ELx initialization
Let's make SCTLR_ELx initialization a bit clearer by using meaningful
names for the initialization values, following the same scheme for
SCTLR_EL1 and SCTLR_EL2.

These definitions will be used more widely in subsequent patches.

There should be no functional change as a result of this patch.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20201113124937.20574-5-mark.rutland@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-12-02 19:44:03 +00:00
Mark Rutland
ecbb11ab3e arm64: head.S: rename el2_setup -> init_kernel_el
For a while now el2_setup has performed some basic initialization of EL1
even when the kernel is booted at EL1, so the name is a little
misleading. Further, some comments are stale as with VHE it doesn't drop
the CPU to EL1.

To clarify things, rename el2_setup to init_kernel_el, and update
comments to be clearer as to the function's purpose.

There should be no functional change as a result of this patch.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20201113124937.20574-4-mark.rutland@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-12-02 19:44:03 +00:00
Ard Biesheuvel
7919385b9f arm64: head: tidy up the Image header definition
Even though support for EFI boot remains entirely optional for arm64,
it is unlikely that we will ever be able to repurpose the image header
fields that the EFI loader relies on, i.e., the magic NOP at offset
0x0 and the PE header address at offset 0x3c.

So let's factor out the differences into a 'efi_signature_nop' macro and
a local symbol representing the PE header address, and move the
conditional definitions into efi-header.S, taking into account whether
CONFIG_EFI is enabled or not. While at it, switch to a signature NOP
that behaves more like a NOP, i.e., one that only clobbers the
flags.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20201117124729.12642-4-ardb@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-11-17 16:14:20 +00:00
Will Deacon
d13027bb35 Revert "arm64: initialize per-cpu offsets earlier"
This reverts commit 353e228eb3.

Qian Cai reports that TX2 no longer boots with his .config as it appears
that task_cpu() gets instrumented and used before KASAN has been
initialised.

Although Mark has a proposed fix, let's take the safe option of reverting
this for now and sorting it out properly later.

Link: https://lore.kernel.org/r/711bc57a314d8d646b41307008db2845b7537b3d.camel@redhat.com
Reported-by: Qian Cai <cai@redhat.com>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
2020-10-09 11:24:17 +01:00
Will Deacon
a82e4ef041 Merge branch 'for-next/late-arrivals' into for-next/core
Late patches for 5.10: MTE selftests, minor KCSAN preparation and removal
of some unused prototypes.

(Amit Daniel Kachhap and others)
* for-next/late-arrivals:
  arm64: random: Remove no longer needed prototypes
  arm64: initialize per-cpu offsets earlier
  kselftest/arm64: Check mte tagged user address in kernel
  kselftest/arm64: Verify KSM page merge for MTE pages
  kselftest/arm64: Verify all different mmap MTE options
  kselftest/arm64: Check forked child mte memory accessibility
  kselftest/arm64: Verify mte tag inclusion via prctl
  kselftest/arm64: Add utilities and a test to validate mte memory
2020-10-07 14:36:24 +01:00
Mark Rutland
353e228eb3 arm64: initialize per-cpu offsets earlier
The current initialization of the per-cpu offset register is difficult
to follow and this initialization is not always early enough for
upcoming instrumentation with KCSAN, where the instrumentation callbacks
use the per-cpu offset.

To make it possible to support KCSAN, and to simplify reasoning about
early bringup code, let's initialize the per-cpu offset earlier, before
we run any C code that may consume it. To do so, this patch adds a new
init_this_cpu_offset() helper that's called before the usual
primary/secondary start functions. For consistency, this is also used to
re-initialize the per-cpu offset after the runtime per-cpu areas have
been allocated (which can change CPU0's offset).

So that init_this_cpu_offset() isn't subject to any instrumentation that
might consume the per-cpu offset, it is marked with noinstr, preventing
instrumentation.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20201005164303.21389-1-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-10-05 18:54:49 +01:00
Ard Biesheuvel
120dc60d0b arm64: get rid of TEXT_OFFSET
TEXT_OFFSET serves no purpose, and for this reason, it was redefined
as 0x0 in the v5.8 timeframe. Since this does not appear to have caused
any issues that require us to revisit that decision, let's get rid of the
macro entirely, along with any references to it.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/20200825135440.11288-1-ardb@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2020-09-07 15:00:52 +01:00
Mike Rapoport
65fddcfca8 mm: reorder includes after introduction of linux/pgtable.h
The replacement of <asm/pgrable.h> with <linux/pgtable.h> made the include
of the latter in the middle of asm includes.  Fix this up with the aid of
the below script and manual adjustments here and there.

	import sys
	import re

	if len(sys.argv) is not 3:
	    print "USAGE: %s <file> <header>" % (sys.argv[0])
	    sys.exit(1)

	hdr_to_move="#include <linux/%s>" % sys.argv[2]
	moved = False
	in_hdrs = False

	with open(sys.argv[1], "r") as f:
	    lines = f.readlines()
	    for _line in lines:
		line = _line.rstrip('
')
		if line == hdr_to_move:
		    continue
		if line.startswith("#include <linux/"):
		    in_hdrs = True
		elif not moved and in_hdrs:
		    moved = True
		    print hdr_to_move
		print line

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200514170327.31389-4-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:13 -07:00
Mike Rapoport
ca5999fde0 mm: introduce include/linux/pgtable.h
The include/linux/pgtable.h is going to be the home of generic page table
manipulation functions.

Start with moving asm-generic/pgtable.h to include/linux/pgtable.h and
make the latter include asm/pgtable.h.

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Cain <bcain@codeaurora.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Ungerer <gerg@linux-m68k.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Guo Ren <guoren@kernel.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ley Foon Tan <ley.foon.tan@intel.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: http://lkml.kernel.org/r/20200514170327.31389-3-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:13 -07:00
Will Deacon
082af5ec50 Merge branch 'for-next/scs' into for-next/core
Support for Clang's Shadow Call Stack in the kernel
(Sami Tolvanen and Will Deacon)
* for-next/scs:
  arm64: entry-ftrace.S: Update comment to indicate that x18 is live
  scs: Move DEFINE_SCS macro into core code
  scs: Remove references to asm/scs.h from core code
  scs: Move scs_overflow_check() out of architecture code
  arm64: scs: Use 'scs_sp' register alias for x18
  scs: Move accounting into alloc/free functions
  arm64: scs: Store absolute SCS stack pointer value in thread_info
  efi/libstub: Disable Shadow Call Stack
  arm64: scs: Add shadow stacks for SDEI
  arm64: Implement Shadow Call Stack
  arm64: Disable SCS for hypervisor code
  arm64: vdso: Disable Shadow Call Stack
  arm64: efi: Restore register x18 if it was corrupted
  arm64: Preserve register x18 when CPU is suspended
  arm64: Reserve register x18 from general allocation with SCS
  scs: Disable when function graph tracing is enabled
  scs: Add support for stack usage debugging
  scs: Add page accounting for shadow call stack allocations
  scs: Add support for Clang's Shadow Call Stack (SCS)
2020-05-28 18:03:40 +01:00
Will Deacon
342403bcb4 Merge branches 'for-next/acpi', 'for-next/bpf', 'for-next/cpufeature', 'for-next/docs', 'for-next/kconfig', 'for-next/misc', 'for-next/perf', 'for-next/ptr-auth', 'for-next/sdei', 'for-next/smccc' and 'for-next/vdso' into for-next/core
ACPI and IORT updates
(Lorenzo Pieralisi)
* for-next/acpi:
  ACPI/IORT: Remove the unused __get_pci_rid()
  ACPI/IORT: Fix PMCG node single ID mapping handling
  ACPI: IORT: Add comments for not calling acpi_put_table()
  ACPI: GTDT: Put GTDT table after parsing
  ACPI: IORT: Add extra message "applying workaround" for off-by-1 issue
  ACPI/IORT: work around num_ids ambiguity
  Revert "ACPI/IORT: Fix 'Number of IDs' handling in iort_id_map()"
  ACPI/IORT: take _DMA methods into account for named components

BPF JIT optimisations for immediate value generation
(Luke Nelson)
* for-next/bpf:
  bpf, arm64: Optimize ADD,SUB,JMP BPF_K using arm64 add/sub immediates
  bpf, arm64: Optimize AND,OR,XOR,JSET BPF_K using arm64 logical immediates
  arm64: insn: Fix two bugs in encoding 32-bit logical immediates

Addition of new CPU ID register fields and removal of some benign sanity checks
(Anshuman Khandual and others)
* for-next/cpufeature: (27 commits)
  KVM: arm64: Check advertised Stage-2 page size capability
  arm64/cpufeature: Add get_arm64_ftr_reg_nowarn()
  arm64/cpuinfo: Add ID_MMFR4_EL1 into the cpuinfo_arm64 context
  arm64/cpufeature: Add remaining feature bits in ID_AA64PFR1 register
  arm64/cpufeature: Add remaining feature bits in ID_AA64PFR0 register
  arm64/cpufeature: Add remaining feature bits in ID_AA64ISAR0 register
  arm64/cpufeature: Add remaining feature bits in ID_MMFR4 register
  arm64/cpufeature: Add remaining feature bits in ID_PFR0 register
  arm64/cpufeature: Introduce ID_MMFR5 CPU register
  arm64/cpufeature: Introduce ID_DFR1 CPU register
  arm64/cpufeature: Introduce ID_PFR2 CPU register
  arm64/cpufeature: Make doublelock a signed feature in ID_AA64DFR0
  arm64/cpufeature: Drop TraceFilt feature exposure from ID_DFR0 register
  arm64/cpufeature: Add explicit ftr_id_isar0[] for ID_ISAR0 register
  arm64/cpufeature: Drop open encodings while extracting parange
  arm64/cpufeature: Validate hypervisor capabilities during CPU hotplug
  arm64: cpufeature: Group indexed system register definitions by name
  arm64: cpufeature: Extend comment to describe absence of field info
  arm64: drop duplicate definitions of ID_AA64MMFR0_TGRAN constants
  arm64: cpufeature: Add an overview comment for the cpufeature framework
  ...

Minor documentation tweaks for silicon errata and booting requirements
(Rob Herring and Will Deacon)
* for-next/docs:
  arm64: silicon-errata.rst: Sort the Cortex-A55 entries
  arm64: docs: Mandate that the I-cache doesn't hold stale kernel text

Minor Kconfig cleanups
(Geert Uytterhoeven)
* for-next/kconfig:
  arm64: cpufeature: Add "or" to mitigations for multiple errata
  arm64: Sort vendor-specific errata

Miscellaneous updates
(Ard Biesheuvel and others)
* for-next/misc:
  arm64: mm: Add asid_gen_match() helper
  arm64: stacktrace: Factor out some common code into on_stack()
  arm64: Call debug_traps_init() from trap_init() to help early kgdb
  arm64: cacheflush: Fix KGDB trap detection
  arm64/cpuinfo: Move device_initcall() near cpuinfo_regs_init()
  arm64: kexec_file: print appropriate variable
  arm: mm: use __pfn_to_section() to get mem_section
  arm64: Reorder the macro arguments in the copy routines
  efi/libstub/arm64: align PE/COFF sections to segment alignment
  KVM: arm64: Drop PTE_S2_MEMATTR_MASK
  arm64/kernel: Fix range on invalidating dcache for boot page tables
  arm64: set TEXT_OFFSET to 0x0 in preparation for removing it entirely
  arm64: lib: Consistently enable crc32 extension
  arm64/mm: Use phys_to_page() to access pgtable memory
  arm64: smp: Make cpus_stuck_in_kernel static
  arm64: entry: remove unneeded semicolon in el1_sync_handler()
  arm64/kernel: vmlinux.lds: drop redundant discard/keep macros
  arm64: drop GZFLAGS definition and export
  arm64: kexec_file: Avoid temp buffer for RNG seed
  arm64: rename stext to primary_entry

Perf PMU driver updates
(Tang Bin and others)
* for-next/perf:
  pmu/smmuv3: Clear IRQ affinity hint on device removal
  drivers/perf: hisi: Permit modular builds of HiSilicon uncore drivers
  drivers/perf: hisi: Fix typo in events attribute array
  drivers/perf: arm_spe_pmu: Avoid duplicate printouts
  drivers/perf: arm_dsu_pmu: Avoid duplicate printouts

Pointer authentication updates and support for vmcoreinfo
(Amit Daniel Kachhap and Mark Rutland)
* for-next/ptr-auth:
  Documentation/vmcoreinfo: Add documentation for 'KERNELPACMASK'
  arm64/crash_core: Export KERNELPACMASK in vmcoreinfo
  arm64: simplify ptrauth initialization
  arm64: remove ptrauth_keys_install_kernel sync arg

SDEI cleanup and non-critical fixes
(James Morse and others)
* for-next/sdei:
  firmware: arm_sdei: Document the motivation behind these set_fs() calls
  firmware: arm_sdei: remove unused interfaces
  firmware: arm_sdei: Put the SDEI table after using it
  firmware: arm_sdei: Drop check for /firmware/ node and always register driver

SMCCC updates and refactoring
(Sudeep Holla)
* for-next/smccc:
  firmware: smccc: Fix missing prototype warning for arm_smccc_version_init
  firmware: smccc: Add function to fetch SMCCC version
  firmware: smccc: Refactor SMCCC specific bits into separate file
  firmware: smccc: Drop smccc_version enum and use ARM_SMCCC_VERSION_1_x instead
  firmware: smccc: Add the definition for SMCCCv1.2 version/error codes
  firmware: smccc: Update link to latest SMCCC specification
  firmware: smccc: Add HAVE_ARM_SMCCC_DISCOVERY to identify SMCCC v1.1 and above

vDSO cleanup and non-critical fixes
(Mark Rutland and Vincenzo Frascino)
* for-next/vdso:
  arm64: vdso: Add --eh-frame-hdr to ldflags
  arm64: vdso: use consistent 'map' nomenclature
  arm64: vdso: use consistent 'abi' nomenclature
  arm64: vdso: simplify arch_vdso_type ifdeffery
  arm64: vdso: remove aarch32_vdso_pages[]
  arm64: vdso: Add '-Bsymbolic' to ldflags
2020-05-28 17:47:34 +01:00
Will Deacon
711e8b0de0 arm64: scs: Use 'scs_sp' register alias for x18
x18 holds the SCS stack pointer value, so introduce a register alias to
make this easier to read in assembly code.

Tested-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
2020-05-18 17:47:37 +01:00
Sami Tolvanen
5287569a79 arm64: Implement Shadow Call Stack
This change implements shadow stack switching, initial SCS set-up,
and interrupt shadow stacks for arm64.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Will Deacon <will@kernel.org>
2020-05-15 16:35:50 +01:00
Gavin Shan
9d2d75ede5 arm64/kernel: Fix range on invalidating dcache for boot page tables
Prior to commit 8eb7e28d4c ("arm64/mm: move runtime pgds to
rodata"), idmap_pgd_dir, tramp_pg_dir, reserved_ttbr0, swapper_pg_dir,
and init_pg_dir were contiguous at the end of the kernel image. The
maintenance at the end of __create_page_tables assumed these were
contiguous, and affected everything from the start of idmap_pg_dir
to the end of init_pg_dir.

That commit moved all but init_pg_dir into the .rodata section, with
other data placed between idmap_pg_dir and init_pg_dir, but did not
update the maintenance. Hence the maintenance is performed on much
more data than necessary (but as the bootloader previously made this
clean to the PoC there is no functional problem).

As we only alter idmap_pg_dir, and init_pg_dir, we only need to perform
maintenance for these. As the other dirs are in .rodata, the bootloader
will have initialised them as expected and cleaned them to the PoC. The
kernel will initialize them as necessary after enabling the MMU.

This patch reworks the maintenance to only cover the idmap_pg_dir and
init_pg_dir to avoid this unnecessary work.

Signed-off-by: Gavin Shan <gshan@redhat.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20200427235700.112220-1-gshan@redhat.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-04-28 14:48:03 +01:00
Ard Biesheuvel
348a625dee arm64: rename stext to primary_entry
For historical reasons, the primary entry routine living somewhere in
the inittext section is called stext(), which is confusing, given that
there is also a section marker called _stext which lives at a fixed
offset in the image (either 64 or 4096 bytes, depending on whether
CONFIG_EFI is enabled)

Let's rename stext to primary_entry(), which is a better description
and reflects the secondary_entry() routine that already exists for
SMP boot.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20200326171423.3080-1-ardb@kernel.org
Reviwed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
2020-04-28 13:55:16 +01:00
Mark Rutland
62a679cb28 arm64: simplify ptrauth initialization
Currently __cpu_setup conditionally initializes the address
authentication keys and enables them in SCTLR_EL1, doing so differently
for the primary CPU and secondary CPUs, and skipping this work for CPUs
returning from an idle state. For the latter case, cpu_do_resume
restores the keys and SCTLR_EL1 value after the MMU has been enabled.

This flow is rather difficult to follow, so instead let's move the
primary and secondary CPU initialization into their respective boot
paths. By following the example of cpu_do_resume and doing so once the
MMU is enabled, we can always initialize the keys from the values in
thread_struct, and avoid the machinery necessary to pass the keys in
secondary_data or open-coding initialization for the boot CPU.

This means we perform an additional RMW of SCTLR_EL1, but we already do
this in the cpu_do_resume path, and for other features in cpufeature.c,
so this isn't a major concern in a bringup path. Note that even while
the enable bits are clear, the key registers are accessible.

As this now renders the argument to __cpu_setup redundant, let's also
remove that entirely. Future extensions can follow a similar approach to
initialize values that differ for primary/secondary CPUs.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Reviewed-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Cc: Amit Daniel Kachhap <amit.kachhap@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20200423101606.37601-3-mark.rutland@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-04-28 11:23:21 +01:00
Catalin Marinas
44ca0e00b6 Merge branch 'for-next/kernel-ptrauth' into for-next/core
* for-next/kernel-ptrauth:
  : Return address signing - in-kernel support
  arm64: Kconfig: verify binutils support for ARM64_PTR_AUTH
  lkdtm: arm64: test kernel pointer authentication
  arm64: compile the kernel with ptrauth return address signing
  kconfig: Add support for 'as-option'
  arm64: suspend: restore the kernel ptrauth keys
  arm64: __show_regs: strip PAC from lr in printk
  arm64: unwind: strip PAC from kernel addresses
  arm64: mask PAC bits of __builtin_return_address
  arm64: initialize ptrauth keys for kernel booting task
  arm64: initialize and switch ptrauth kernel keys
  arm64: enable ptrauth earlier
  arm64: cpufeature: handle conflicts based on capability
  arm64: cpufeature: Move cpu capability helpers inside C file
  arm64: ptrauth: Add bootup/runtime flags for __cpu_setup
  arm64: install user ptrauth keys at kernel exit time
  arm64: rename ptrauth key structures to be user-specific
  arm64: cpufeature: add pointer auth meta-capabilities
  arm64: cpufeature: Fix meta-capability cpufeature check
2020-03-25 11:11:08 +00:00
Catalin Marinas
806dc825f0 Merge branch 'for-next/asm-cleanups' into for-next/core
* for-next/asm-cleanups:
  : Various asm clean-ups (alignment, mov_q vs ldr, .idmap)
  arm64: move kimage_vaddr to .rodata
  arm64: use mov_q instead of literal ldr
2020-03-25 11:10:51 +00:00
Catalin Marinas
0829a07695 Merge branch 'for-next/asm-annotations' into for-next/core
* for-next/asm-annotations:
  : Modernise arm64 assembly annotations
  arm64: head: Convert install_el2_stub to SYM_INNER_LABEL
  arm64: Mark call_smc_arch_workaround_1 as __maybe_unused
  arm64: entry-ftrace.S: Fix missing argument for CONFIG_FUNCTION_GRAPH_TRACER=y
  arm64: vdso32: Convert to modern assembler annotations
  arm64: vdso: Convert to modern assembler annotations
  arm64: sdei: Annotate SDEI entry points using new style annotations
  arm64: kvm: Modernize __smccc_workaround_1_smc_start annotations
  arm64: kvm: Modernize annotation for __bp_harden_hyp_vecs
  arm64: kvm: Annotate assembly using modern annoations
  arm64: kernel: Convert to modern annotations for assembly data
  arm64: head: Annotate stext and preserve_boot_args as code
  arm64: head.S: Convert to modern annotations for assembly functions
  arm64: ftrace: Modernise annotation of return_to_handler
  arm64: ftrace: Correct annotation of ftrace_caller assembly
  arm64: entry-ftrace.S: Convert to modern annotations for assembly functions
  arm64: entry: Additional annotation conversions for entry.S
  arm64: entry: Annotate ret_from_fork as code
  arm64: entry: Annotate vector table and handlers as code
  arm64: crypto: Modernize names for AES function macros
  arm64: crypto: Modernize some extra assembly annotations
2020-03-25 11:10:46 +00:00
Mark Brown
d4abd29d67 arm64: head: Convert install_el2_stub to SYM_INNER_LABEL
New assembly annotations have recently been introduced which aim to
make the way we describe symbols in assembly more consistent. Recently the
arm64 assembler was converted to use these but install_el2_stub was missed.

Signed-off-by: Mark Brown <broonie@kernel.org>
[catalin.marinas@arm.com: changed to SYM_L_LOCAL]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-03-25 11:07:39 +00:00
Remi Denis-Courmont
6cf9a2dce6 arm64: move kimage_vaddr to .rodata
This datum is not referenced from .idmap.text: it does not need to be
mapped in idmap. Lets move it to .rodata as it is never written to after
early boot of the primary CPU.
(Maybe .data.ro_after_init would be cleaner though?)

Signed-off-by: Rémi Denis-Courmont <remi@remlab.net>
Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-03-24 11:48:24 +00:00
Amit Daniel Kachhap
df3551011b arm64: ptrauth: Add bootup/runtime flags for __cpu_setup
This patch allows __cpu_setup to be invoked with one of these flags,
ARM64_CPU_BOOT_PRIMARY, ARM64_CPU_BOOT_SECONDARY or ARM64_CPU_RUNTIME.
This is required as some cpufeatures need different handling during
different scenarios.

The input parameter in x0 is preserved till the end to be used inside
this function.

There should be no functional change with this patch and is useful
for the subsequent ptrauth patch which utilizes it. Some upcoming
arm cpufeatures can also utilize these flags.

Suggested-by: James Morse <james.morse@arm.com>
Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Reviewed-by: Vincenzo Frascino <Vincenzo.Frascino@arm.com>
Reviewed-by: James Morse <james.morse@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-03-18 09:50:19 +00:00
Mark Brown
a5d4420b26 arm64: kernel: Convert to modern annotations for assembly data
In an effort to clarify and simplify the annotation of assembly functions
in the kernel new macros have been introduced. These include specific
annotations for the start and end of data, update symbols for data to use
these.

Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-03-09 17:35:24 +00:00
Mark Brown
ebdf44a189 arm64: head: Annotate stext and preserve_boot_args as code
In an effort to clarify and simplify the annotation of assembly
functions new macros have been introduced. These replace ENTRY and
ENDPROC with two different annotations for normal functions and those
with unusual calling conventions.  Neither stext nor preserve_boot_args
is called with the usual AAPCS calling conventions and they should
therefore be annotated as code.

Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-03-09 17:35:20 +00:00
Mark Brown
c63d9f82db arm64: head.S: Convert to modern annotations for assembly functions
In an effort to clarify and simplify the annotation of assembly functions
in the kernel new macros have been introduced. These replace ENTRY and
ENDPROC and also add a new annotation for static functions which previously
had no ENTRY equivalent. Update the annotations in the core kernel code to
the new macros.

Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-03-09 17:35:18 +00:00
Remi Denis-Courmont
857a141d7f arm64: remove gratuitious/stray .ltorg stanzas
There are no applicable literals above them.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Remi Denis-Courmont <remi.denis.courmont@huawei.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-03-04 15:47:47 +00:00
Will Deacon
ac12cf85d6 Merge branches 'for-next/52-bit-kva', 'for-next/cpu-topology', 'for-next/error-injection', 'for-next/perf', 'for-next/psci-cpuidle', 'for-next/rng', 'for-next/smpboot', 'for-next/tbi' and 'for-next/tlbi' into for-next/core
* for-next/52-bit-kva: (25 commits)
  Support for 52-bit virtual addressing in kernel space

* for-next/cpu-topology: (9 commits)
  Move CPU topology parsing into core code and add support for ACPI 6.3

* for-next/error-injection: (2 commits)
  Support for function error injection via kprobes

* for-next/perf: (8 commits)
  Support for i.MX8 DDR PMU and proper SMMUv3 group validation

* for-next/psci-cpuidle: (7 commits)
  Move PSCI idle code into a new CPUidle driver

* for-next/rng: (4 commits)
  Support for 'rng-seed' property being passed in the devicetree

* for-next/smpboot: (3 commits)
  Reduce fragility of secondary CPU bringup in debug configurations

* for-next/tbi: (10 commits)
  Introduce new syscall ABI with relaxed requirements for pointer tags

* for-next/tlbi: (6 commits)
  Handle spurious page faults arising from kernel space
2019-08-30 12:46:12 +01:00
Will Deacon
5b1cfe3a0b arm64: smp: Don't enter kernel with NULL stack pointer or task struct
Although SMP bringup is inherently racy, we can significantly reduce
the window during which secondary CPUs can unexpectedly enter the
kernel by sanity checking the 'stack' and 'task' fields of the
'secondary_data' structure. If the booting CPU gave up waiting for us,
then they will have been cleared to NULL and we should spin in a WFE; WFI
loop instead.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
2019-08-27 17:37:02 +01:00
Steve Capper
2c624fe687 arm64: mm: Remove vabits_user
Previous patches have enabled 52-bit kernel + user VAs and there is no
longer any scenario where user VA != kernel VA size.

This patch removes the, now redundant, vabits_user variable and replaces
usage with vabits_actual where appropriate.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Steve Capper <steve.capper@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
2019-08-09 11:17:27 +01:00
Steve Capper
b6d00d47e8 arm64: mm: Introduce 52-bit Kernel VAs
Most of the machinery is now in place to enable 52-bit kernel VAs that
are detectable at boot time.

This patch adds a Kconfig option for 52-bit user and kernel addresses
and plumbs in the requisite CONFIG_ macros as well as sets TCR.T1SZ,
physvirt_offset and vmemmap at early boot.

To simplify things this patch also removes the 52-bit user/48-bit kernel
kconfig option.

Signed-off-by: Steve Capper <steve.capper@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
2019-08-09 11:17:26 +01:00
Steve Capper
c812026c54 arm64: mm: Logic to make offset_ttbr1 conditional
When running with a 52-bit userspace VA and a 48-bit kernel VA we offset
ttbr1_el1 to allow the kernel pagetables with a 52-bit PTRS_PER_PGD to
be used for both userspace and kernel.

Moving on to a 52-bit kernel VA we no longer require this offset to
ttbr1_el1 should we be running on a system with HW support for 52-bit
VAs.

This patch introduces conditional logic to offset_ttbr1 to query
SYS_ID_AA64MMFR2_EL1 whenever 52-bit VAs are selected. If there is HW
support for 52-bit VAs then the ttbr1 offset is skipped.

We choose to read a system register rather than vabits_actual because
offset_ttbr1 can be called in places where the kernel data is not
actually mapped.

Calls to offset_ttbr1 appear to be made from rarely called code paths so
this extra logic is not expected to adversely affect performance.

Signed-off-by: Steve Capper <steve.capper@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
2019-08-09 11:17:24 +01:00
Steve Capper
5383cc6efe arm64: mm: Introduce vabits_actual
In order to support 52-bit kernel addresses detectable at boot time, one
needs to know the actual VA_BITS detected. A new variable vabits_actual
is introduced in this commit and employed for the KVM hypervisor layout,
KASAN, fault handling and phys-to/from-virt translation where there
would normally be compile time constants.

In order to maintain performance in phys_to_virt, another variable
physvirt_offset is introduced.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Steve Capper <steve.capper@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
2019-08-09 11:17:21 +01:00
Steve Capper
90ec95cda9 arm64: mm: Introduce VA_BITS_MIN
In order to support 52-bit kernel addresses detectable at boot time, the
kernel needs to know the most conservative VA_BITS possible should it
need to fall back to this quantity due to lack of hardware support.

A new compile time constant VA_BITS_MIN is introduced in this patch and
it is employed in the KASAN end address, KASLR, and EFI stub.

For Arm, if 52-bit VA support is unavailable the fallback is to 48-bits.

In other words: VA_BITS_MIN = min (48, VA_BITS)

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Steve Capper <steve.capper@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
2019-08-09 11:17:16 +01:00
Peter Collingbourne
5cf896fb6b arm64: Add support for relocating the kernel with RELR relocations
RELR is a relocation packing format for relative relocations.
The format is described in a generic-abi proposal:
https://groups.google.com/d/topic/generic-abi/bX460iggiKg/discussion

The LLD linker can be instructed to pack relocations in the RELR
format by passing the flag --pack-dyn-relocs=relr.

This patch adds a new config option, CONFIG_RELR. Enabling this option
instructs the linker to pack vmlinux's relative relocations in the RELR
format, and causes the kernel to apply the relocations at startup along
with the RELA relocations. RELA relocations still need to be applied
because the linker will emit RELA relative relocations if they are
unrepresentable in the RELR format (i.e. address not a multiple of 2).

Enabling CONFIG_RELR reduces the size of a defconfig kernel image
with CONFIG_RANDOMIZE_BASE by 3.5MB/16% uncompressed, or 550KB/5%
compressed (lz4).

Signed-off-by: Peter Collingbourne <pcc@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
2019-08-05 12:35:35 +01:00
Thomas Gleixner
caab277b1d treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation this program is
  distributed in the hope that it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details you should have received a copy of the gnu general
  public license along with this program if not see http www gnu org
  licenses

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 503 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Enrico Weigelt <info@metux.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190602204653.811534538@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:07 +02:00
Arun KS
61cf61d81e arm64: Fix size of __early_cpu_boot_status
__early_cpu_boot_status is of type long. Use quad
assembler directive to allocate proper size.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Arun KS <arunks@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-05-01 14:39:26 +01:00
Alexandru Elisei
f6e564354a arm64: Use defines instead of magic numbers
Following assembly code is not trivial; make it slightly easier to read by
replacing some of the magic numbers with the defines which are already
present in sysreg.h.

Reviewed-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-05 12:32:00 +01:00
Vladimir Murzin
74698f6971 arm64: Relax GIC version check during early boot
Updates to the GIC architecture allow ID_AA64PFR0_EL1.GIC to have
values other than 0 or 1. At the moment, Linux is quite strict in the
way it handles this field at early boot stage (cpufeature is fine) and
will refuse to use the system register CPU interface if it doesn't
find the value 1.

Fixes: 021f653791 ("irqchip: gic-v3: Initial support for GICv3")
Reported-by: Chase Conklin <Chase.Conklin@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-02-20 14:05:37 +00:00
Will Deacon
b89d82ef01 arm64: kpti: Avoid rewriting early page tables when KASLR is enabled
A side effect of commit c55191e96c ("arm64: mm: apply r/o permissions
of VM areas to its linear alias as well") is that the linear map is
created with page granularity, which means that transitioning the early
page table from global to non-global mappings when enabling kpti can
take a significant amount of time during boot.

Given that most CPU implementations do not require kpti, this mainly
impacts KASLR builds where kpti is forcefully enabled. However, in these
situations we know early on that non-global mappings are required and
can avoid the use of global mappings from the beginning. The only gotcha
is Cavium erratum #27456, which we must detect based on the MIDR value
of the boot CPU.

Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reported-by: John Garry <john.garry@huawei.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-01-10 17:49:35 +00:00
Mark Rutland
4eaed6aa2c arm64/kvm: consistently handle host HCR_EL2 flags
In KVM we define the configuration of HCR_EL2 for a VHE HOST in
HCR_HOST_VHE_FLAGS, but we don't have a similar definition for the
non-VHE host flags, and open-code HCR_RW. Further, in head.S we
open-code the flags for VHE and non-VHE configurations.

In future, we're going to want to configure more flags for the host, so
lets add a HCR_HOST_NVHE_FLAGS defintion, and consistently use both
HCR_HOST_VHE_FLAGS and HCR_HOST_NVHE_FLAGS in the kvm code and head.S.

We now use mov_q to generate the HCR_EL2 value, as we use when
configuring other registers in head.S.

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: kvmarm@lists.cs.columbia.edu
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-12-13 16:42:45 +00:00
Will Deacon
d34664f63b Merge branch 'for-next/kexec' into aarch64/for-next/core
Merge in kexec_file_load() support from Akashi Takahiro.
2018-12-10 18:57:17 +00:00
Will Deacon
66f16a2451 arm64: smp: Rework early feature mismatched detection
Rather than add additional variables to detect specific early feature
mismatches with secondary CPUs, we can instead dedicate the upper bits
of the CPU boot status word to flag specific mismatches.

This allows us to communicate both granule and VA-size mismatches back
to the primary CPU without the need for additional book-keeping.

Tested-by: Steve Capper <steve.capper@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-12-10 18:42:18 +00:00
Will Deacon
68d23da437 arm64: Kconfig: Re-jig CONFIG options for 52-bit VA
Enabling 52-bit VAs for userspace is pretty confusing, since it requires
you to select "48-bit" virtual addressing in the Kconfig.

Rework the logic so that 52-bit user virtual addressing is advertised in
the "Virtual address space size" choice, along with some help text to
describe its interaction with Pointer Authentication. The EXPERT-only
option to force all user mappings to the 52-bit range is then made
available immediately below the VA size selection.

Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-12-10 18:42:18 +00:00
Steve Capper
67e7fdfcc6 arm64: mm: introduce 52-bit userspace support
On arm64 there is optional support for a 52-bit virtual address space.
To exploit this one has to be running with a 64KB page size and be
running on hardware that supports this.

For an arm64 kernel supporting a 48 bit VA with a 64KB page size,
some changes are needed to support a 52-bit userspace:
 * TCR_EL1.T0SZ needs to be 12 instead of 16,
 * TASK_SIZE needs to reflect the new size.

This patch implements the above when the support for 52-bit VAs is
detected at early boot time.

On arm64 userspace addresses translation is controlled by TTBR0_EL1. As
well as userspace, TTBR0_EL1 controls:
 * The identity mapping,
 * EFI runtime code.

It is possible to run a kernel with an identity mapping that has a
larger VA size than userspace (and for this case __cpu_set_tcr_t0sz()
would set TCR_EL1.T0SZ as appropriate). However, when the conditions for
52-bit userspace are met; it is possible to keep TCR_EL1.T0SZ fixed at
12. Thus in this patch, the TCR_EL1.T0SZ size changing logic is
disabled.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Steve Capper <steve.capper@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-12-10 18:42:17 +00:00
Steve Capper
a96a33b1ca arm64: mm: Prevent mismatched 52-bit VA support
For cases where there is a mismatch in ARMv8.2-LVA support between CPUs
we have to be careful in allowing secondary CPUs to boot if 52-bit
virtual addresses have already been enabled on the boot CPU.

This patch adds code to the secondary startup path. If the boot CPU has
enabled 52-bit VAs then ID_AA64MMFR2_EL1 is checked to see if the
secondary can also enable 52-bit support. If not, the secondary is
prevented from booting and an error message is displayed indicating why.

Technically this patch could be implemented using the cpufeature code
when considering 52-bit userspace support. However, we employ low level
checks here as the cpufeature code won't be able to run if we have
mismatched 52-bit kernel va support.

Signed-off-by: Steve Capper <steve.capper@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-12-10 18:42:17 +00:00
Steve Capper
e842dfb5a2 arm64: mm: Offset TTBR1 to allow 52-bit PTRS_PER_PGD
Enabling 52-bit VAs on arm64 requires that the PGD table expands from 64
entries (for the 48-bit case) to 1024 entries. This quantity,
PTRS_PER_PGD is used as follows to compute which PGD entry corresponds
to a given virtual address, addr:

pgd_index(addr) -> (addr >> PGDIR_SHIFT) & (PTRS_PER_PGD - 1)

Userspace addresses are prefixed by 0's, so for a 48-bit userspace
address, uva, the following is true:
(uva >> PGDIR_SHIFT) & (1024 - 1) == (uva >> PGDIR_SHIFT) & (64 - 1)

In other words, a 48-bit userspace address will have the same pgd_index
when using PTRS_PER_PGD = 64 and 1024.

Kernel addresses are prefixed by 1's so, given a 48-bit kernel address,
kva, we have the following inequality:
(kva >> PGDIR_SHIFT) & (1024 - 1) != (kva >> PGDIR_SHIFT) & (64 - 1)

In other words a 48-bit kernel virtual address will have a different
pgd_index when using PTRS_PER_PGD = 64 and 1024.

If, however, we note that:
kva = 0xFFFF << 48 + lower (where lower[63:48] == 0b)
and, PGDIR_SHIFT = 42 (as we are dealing with 64KB PAGE_SIZE)

We can consider:
(kva >> PGDIR_SHIFT) & (1024 - 1) - (kva >> PGDIR_SHIFT) & (64 - 1)
 = (0xFFFF << 6) & 0x3FF - (0xFFFF << 6) & 0x3F	// "lower" cancels out
 = 0x3C0

In other words, one can switch PTRS_PER_PGD to the 52-bit value globally
provided that they increment ttbr1_el1 by 0x3C0 * 8 = 0x1E00 bytes when
running with 48-bit kernel VAs (TCR_EL1.T1SZ = 16).

For kernel configuration where 52-bit userspace VAs are possible, this
patch offsets ttbr1_el1 and sets PTRS_PER_PGD corresponding to the
52-bit value.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Suggested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Steve Capper <steve.capper@arm.com>
[will: added comment to TTBR1_BADDR_4852_OFFSET calculation]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-12-10 18:42:17 +00:00
AKASHI Takahiro
f56063c51f arm64: add image head flag definitions
Those image head's flags will be used later by kexec_file loader.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Acked-by: James Morse <james.morse@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-12-06 14:38:51 +00:00
Jun Yao
8eb7e28d4c arm64/mm: move runtime pgds to rodata
Now that deliberate writes to swapper_pg_dir are made via the fixmap, we
can defend against errant writes by moving it into the rodata section.
Since tramp_pg_dir and reserved_ttbr0 must be at a fixed offset from
swapper_pg_dir, and are not modified at runtime, these are also moved
into the rodata section. Likewise, idmap_pg_dir is not modified at
runtime, and is moved into rodata.

Signed-off-by: Jun Yao <yaojun8558363@gmail.com>
Reviewed-by: James Morse <james.morse@arm.com>
[Mark: simplify linker script, commit message]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-25 15:10:55 +01:00
Jun Yao
2b5548b681 arm64/mm: Separate boot-time page tables from swapper_pg_dir
Since the address of swapper_pg_dir is fixed for a given kernel image,
it is an attractive target for manipulation via an arbitrary write. To
mitigate this we'd like to make it read-only by moving it into the
rodata section.

We require that swapper_pg_dir is at a fixed offset from tramp_pg_dir
and reserved_ttbr0, so these will also need to move into rodata.
However, swapper_pg_dir is allocated along with some transient page
tables used for boot which we do not want to move into rodata.

As a step towards this, this patch separates the boot-time page tables
into a new init_pg_dir, and reduces swapper_pg_dir to the single page it
needs to be. This allows us to retain the relationship between
swapper_pg_dir, tramp_pg_dir, and swapper_pg_dir, while cleanly
separating these from the boot-time page tables.

The init_pg_dir holds all of the pgd/pud/pmd/pte levels needed during
boot, and all of these levels will be freed when we switch to the
swapper_pg_dir, which is initialized by the existing code in
paging_init(). Since we start off on the init_pg_dir, we no longer need
to allocate a transient page table in paging_init() in order to ensure
that swapper_pg_dir isn't live while we initialize it.

There should be no functional change as a result of this patch.

Signed-off-by: Jun Yao <yaojun8558363@gmail.com>
Reviewed-by: James Morse <james.morse@arm.com>
[Mark: place init_pg_dir after BSS, fold mm changes, commit message]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-25 15:10:54 +01:00
Jun Yao
693d5639b4 arm64/mm: Pass ttbr1 as a parameter to __enable_mmu()
In subsequent patches we'll use a transient pgd during the primary cpu's
boot process. To make this work while allowing secondary cpus to use the
swapper_pg_dir, we need to pass the relevant TTBR1 pgd as a parameter
to __enable_mmu().

This patch updates __enable__mmu() to take this as a parameter, updating
callsites to pass swapper_pg_dir for now.

There should be no functional change as a result of this patch.

Signed-off-by: Jun Yao <yaojun8558363@gmail.com>
Reviewed-by: James Morse <james.morse@arm.com>
[Mark: simplify assembly, clarify commit message]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-09-25 15:10:54 +01:00
Mark Rutland
cc33c4e201 arm64/kvm: Prohibit guest LOR accesses
We don't currently limit guest accesses to the LOR registers, which we
neither virtualize nor context-switch. As such, guests are provided with
unusable information/controls, and are not isolated from each other (or
the host).

To prevent these issues, we can trap register accesses and present the
illusion LORegions are unssupported by the CPU. To do this, we mask
ID_AA64MMFR1.LO, and set HCR_EL2.TLOR to trap accesses to the following
registers:

* LORC_EL1
* LOREA_EL1
* LORID_EL1
* LORN_EL1
* LORSA_EL1

... when trapped, we inject an UNDEFINED exception to EL1, simulating
their non-existence.

As noted in D7.2.67, when no LORegions are implemented, LoadLOAcquire
and StoreLORelease must behave as LoadAcquire and StoreRelease
respectively. We can ensure this by clearing LORC_EL1.EN when a CPU's
EL2 is first initialized, as the host kernel will not modify this.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Vladimir Murzin <vladimir.murzin@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: kvmarm@lists.cs.columbia.edu
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2018-02-26 10:48:01 +01:00
Will Deacon
439e70e27a arm64: idmap: Use "awx" flags for .idmap.text .pushsection directives
The identity map is mapped as both writeable and executable by the
SWAPPER_MM_MMUFLAGS and this is relied upon by the kpti code to manage
a synchronisation flag. Update the .pushsection flags to reflect the
actual mapping attributes.

Reported-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-06 22:53:27 +00:00
Will Deacon
79ddab3b05 arm64: assembler: Align phys_to_pte with pte_to_phys
pte_to_phys lives in assembler.h and takes its destination register as
the first argument. Move phys_to_pte out of head.S to sit with its
counterpart and rejig it to follow the same calling convention.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-06 22:53:25 +00:00
Will Deacon
fa0465fc07 arm64: assembler: Change order of macro arguments in phys_to_ttbr
Since AArch64 assembly instructions take the destination register as
their first operand, do the same thing for the phys_to_ttbr macro.

Acked-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-06 22:53:21 +00:00
Shanker Donthineni
3060e9f0d1 arm64: Add software workaround for Falkor erratum 1041
The ARM architecture defines the memory locations that are permitted
to be accessed as the result of a speculative instruction fetch from
an exception level for which all stages of translation are disabled.
Specifically, the core is permitted to speculatively fetch from the
4KB region containing the current program counter 4K and next 4K.

When translation is changed from enabled to disabled for the running
exception level (SCTLR_ELn[M] changed from a value of 1 to 0), the
Falkor core may errantly speculatively access memory locations outside
of the 4KB region permitted by the architecture. The errant memory
access may lead to one of the following unexpected behaviors.

1) A System Error Interrupt (SEI) being raised by the Falkor core due
   to the errant memory access attempting to access a region of memory
   that is protected by a slave-side memory protection unit.
2) Unpredictable device behavior due to a speculative read from device
   memory. This behavior may only occur if the instruction cache is
   disabled prior to or coincident with translation being changed from
   enabled to disabled.

The conditions leading to this erratum will not occur when either of the
following occur:
 1) A higher exception level disables translation of a lower exception level
   (e.g. EL2 changing SCTLR_EL1[M] from a value of 1 to 0).
 2) An exception level disabling its stage-1 translation if its stage-2
    translation is enabled (e.g. EL1 changing SCTLR_EL1[M] from a value of 1
    to 0 when HCR_EL2[VM] has a value of 1).

To avoid the errant behavior, software must execute an ISB immediately
prior to executing the MSR that will change SCTLR_ELn[M] from 1 to 0.

Signed-off-by: Shanker Donthineni <shankerd@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-06 22:53:13 +00:00
James Morse
7a00d68ebe arm64: sysreg: Move to use definitions for all the SCTLR bits
__cpu_setup() configures SCTLR_EL1 using some hard coded hex masks,
and el2_setup() duplicates some this when setting RES1 bits.

Lets make this the same as KVM's hyp_init, which uses named bits.

First, we add definitions for all the SCTLR_EL{1,2} bits, the RES{1,0}
bits, and those we want to set or clear.

Add a build_bug checks to ensures all bits are either set or clear.
This means we don't need to preserve endian-ness configuration
generated elsewhere.

Finally, move the head.S and proc.S users of these hard-coded masks
over to the macro versions.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-01-16 15:05:39 +00:00
Steve Capper
0370b31e48 arm64: Extend early page table code to allow for larger kernels
Currently the early assembler page table code assumes that precisely
1xpgd, 1xpud, 1xpmd are sufficient to represent the early kernel text
mappings.

Unfortunately this is rarely the case when running with a 16KB granule,
and we also run into limits with 4KB granule when building much larger
kernels.

This patch re-writes the early page table logic to compute indices of
mappings for each level of page table, and if multiple indices are
required, the next-level page table is scaled up accordingly.

Also the required size of the swapper_pg_dir is computed at link time
to cover the mapping [KIMAGE_ADDR + VOFFSET, _end]. When KASLR is
enabled, an extra page is set aside for each level that may require extra
entries at runtime.

Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Steve Capper <steve.capper@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-01-14 18:49:52 +00:00
Kristina Martsenko
fa2a8445b1 arm64: allow ID map to be extended to 52 bits
Currently, when using VA_BITS < 48, if the ID map text happens to be
placed in physical memory above VA_BITS, we increase the VA size (up to
48) and create a new table level, in order to map in the ID map text.
This is okay because the system always supports 48 bits of VA.

This patch extends the code such that if the system supports 52 bits of
VA, and the ID map text is placed that high up, then we increase the VA
size accordingly, up to 52.

One difference from the current implementation is that so far the
condition of VA_BITS < 48 has meant that the top level table is always
"full", with the maximum number of entries, and an extra table level is
always needed. Now, when VA_BITS = 48 (and using 64k pages), the top
level table is not full, and we simply need to increase the number of
entries in it, instead of creating a new table level.

Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
[catalin.marinas@arm.com: reduce arguments to __create_hyp_mappings()]
[catalin.marinas@arm.com: reworked/renamed __cpu_uses_extended_idmap_level()]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-12-22 17:37:33 +00:00
Kristina Martsenko
75387b9263 arm64: handle 52-bit physical addresses in page table entries
The top 4 bits of a 52-bit physical address are positioned at bits
12..15 of a page table entry. Introduce macros to convert between a
physical address and its placement in a table entry, and change all
macros/functions that access PTEs to use them.

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Tested-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
[catalin.marinas@arm.com: some long lines wrapped]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-12-22 17:37:18 +00:00
Kristina Martsenko
e6d588a8e3 arm64: head.S: handle 52-bit PAs in PTEs in early page table setup
The top 4 bits of a 52-bit physical address are positioned at bits
12..15 in page table entries. Introduce a macro to move the bits there,
and change the early ID map and swapper table setup code to use it.

Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
[catalin.marinas@arm.com: additional comments for clarification]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-12-22 17:35:55 +00:00
Kristina Martsenko
529c4b05a3 arm64: handle 52-bit addresses in TTBR
The top 4 bits of a 52-bit physical address are positioned at bits 2..5
in the TTBR registers. Introduce a couple of macros to move the bits
there, and change all TTBR writers to use them.

Leave TTBR0 PAN code unchanged, to avoid complicating it. A system with
52-bit PA will have PAN anyway (because it's ARMv8.1 or later), and a
system without 52-bit PA can only use up to 48-bit PAs. A later patch in
this series will add a kconfig dependency to ensure PAN is configured.

In addition, when using 52-bit PA there is a special alignment
requirement on the top-level table. We don't currently have any VA_BITS
configuration that would violate the requirement, but one could be added
in the future, so add a compile-time BUG_ON to check for it.

Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
[catalin.marinas@arm.com: added TTBR_BADD_MASK_52 comment]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-12-22 17:35:21 +00:00
Dave Martin
22043a3c08 arm64/sve: Low-level CPU setup
To enable the kernel to use SVE, SVE traps from EL1 to EL2 must be
disabled.  To take maximum advantage of the hardware, the full
available vector length also needs to be enabled for EL1 by
programming ZCR_EL2.LEN.  (The kernel will program ZCR_EL1.LEN as
required, but this cannot override the limit set by ZCR_EL2.)

This patch makes the appropriate changes to the EL2 early setup
code.

Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-11-03 15:24:15 +00:00
Will Deacon
b0c57e1071 arm64: head: Init PMSCR_EL2.{PA,PCT} when entered at EL2 without VHE
When booting at EL2, ensure that we permit the EL1 host to sample
physical addresses and physical counter values using SPE.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-18 12:53:32 +01:00
Marc Zyngier
5371513fb3 arm64: Make sure SPsel is always set
When the kernel is entered at EL2 on an ARMv8.0 system, we construct
the EL1 pstate and make sure this uses the the EL1 stack pointer
(we perform an exception return to EL1h).

But if the kernel is either entered at EL1 or stays at EL2 (because
we're on a VHE-capable system), we fail to set SPsel, and use whatever
stack selection the higher exception level has choosen for us.

Let's not take any chance, and make sure that SPsel is set to one
before we decide the mode we're going to run in.

Cc: <stable@vger.kernel.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-09-27 12:15:54 +01:00
Linus Torvalds
04759194dc arm64 updates for 4.14:
- VMAP_STACK support, allowing the kernel stacks to be allocated in
   the vmalloc space with a guard page for trapping stack overflows. One
   of the patches introduces THREAD_ALIGN and changes the generic
   alloc_thread_stack_node() to use this instead of THREAD_SIZE (no
   functional change for other architectures)
 
 - Contiguous PTE hugetlb support re-enabled (after being reverted a
   couple of times). We now have the semantics agreed in the generic mm
   layer together with API improvements so that the architecture code can
   detect between contiguous and non-contiguous huge PTEs
 
 - Initial support for persistent memory on ARM: DC CVAP instruction
   exposed to user space (HWCAP) and the in-kernel pmem API implemented
 
 - raid6 improvements for arm64: faster algorithm for the delta syndrome
   and implementation of the recovery routines using Neon
 
 - FP/SIMD refactoring and removal of support for Neon in interrupt
   context. This is in preparation for full SVE support
 
 - PTE accessors converted from inline asm to cmpxchg so that we can
   use LSE atomics if available (ARMv8.1)
 
 - Perf support for Cortex-A35 and A73
 
 - Non-urgent fixes and cleanups
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Catalin Marinas:

 - VMAP_STACK support, allowing the kernel stacks to be allocated in the
   vmalloc space with a guard page for trapping stack overflows. One of
   the patches introduces THREAD_ALIGN and changes the generic
   alloc_thread_stack_node() to use this instead of THREAD_SIZE (no
   functional change for other architectures)

 - Contiguous PTE hugetlb support re-enabled (after being reverted a
   couple of times). We now have the semantics agreed in the generic mm
   layer together with API improvements so that the architecture code
   can detect between contiguous and non-contiguous huge PTEs

 - Initial support for persistent memory on ARM: DC CVAP instruction
   exposed to user space (HWCAP) and the in-kernel pmem API implemented

 - raid6 improvements for arm64: faster algorithm for the delta syndrome
   and implementation of the recovery routines using Neon

 - FP/SIMD refactoring and removal of support for Neon in interrupt
   context. This is in preparation for full SVE support

 - PTE accessors converted from inline asm to cmpxchg so that we can use
   LSE atomics if available (ARMv8.1)

 - Perf support for Cortex-A35 and A73

 - Non-urgent fixes and cleanups

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (75 commits)
  arm64: cleanup {COMPAT_,}SET_PERSONALITY() macro
  arm64: introduce separated bits for mm_context_t flags
  arm64: hugetlb: Cleanup setup_hugepagesz
  arm64: Re-enable support for contiguous hugepages
  arm64: hugetlb: Override set_huge_swap_pte_at() to support contiguous hugepages
  arm64: hugetlb: Override huge_pte_clear() to support contiguous hugepages
  arm64: hugetlb: Handle swap entries in huge_pte_offset() for contiguous hugepages
  arm64: hugetlb: Add break-before-make logic for contiguous entries
  arm64: hugetlb: Spring clean huge pte accessors
  arm64: hugetlb: Introduce pte_pgprot helper
  arm64: hugetlb: set_huge_pte_at Add WARN_ON on !pte_present
  arm64: kexec: have own crash_smp_send_stop() for crash dump for nonpanic cores
  arm64: dma-mapping: Mark atomic_pool as __ro_after_init
  arm64: dma-mapping: Do not pass data to gen_pool_set_algo()
  arm64: Remove the !CONFIG_ARM64_HW_AFDBM alternative code paths
  arm64: Ignore hardware dirty bit updates in ptep_set_wrprotect()
  arm64: Move PTE_RDONLY bit handling out of set_pte_at()
  kvm: arm64: Convert kvm_set_s2pte_readonly() from inline asm to cmpxchg()
  arm64: Convert pte handling from inline asm to using (cmp)xchg
  arm64: neon/efi: Make EFI fpsimd save/restore variables static
  ...
2017-09-05 09:53:37 -07:00
Ard Biesheuvel
4a23e56ad6 arm64: kaslr: ignore modulo offset when validating virtual displacement
In the KASLR setup routine, we ensure that the early virtual mapping
of the kernel image does not cover more than a single table entry at
the level above the swapper block level, so that the assembler routines
involved in setting up this mapping can remain simple.

In this calculation we add the proposed KASLR offset to the values of
the _text and _end markers, and reject it if they would end up falling
in different swapper table sized windows.

However, when taking the addresses of _text and _end, the modulo offset
(the physical displacement modulo 2 MB) is already accounted for, and
so adding it again results in incorrect results. So disregard the modulo
offset from the calculation.

Fixes: 08cdac619c ("arm64: relocatable: deal with physically misaligned ...")
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-08-22 18:15:42 +01:00
Catalin Marinas
0553896787 Merge branch 'arm64/exception-stack' of git://git.kernel.org/pub/scm/linux/kernel/git/mark/linux into for-next/core
* 'arm64/exception-stack' of git://git.kernel.org/pub/scm/linux/kernel/git/mark/linux:
  arm64: unwind: remove sp from struct stackframe
  arm64: unwind: reference pt_regs via embedded stack frame
  arm64: unwind: disregard frame.sp when validating frame pointer
  arm64: unwind: avoid percpu indirection for irq stack
  arm64: move non-entry code out of .entry.text
  arm64: consistently use bl for C exception entry
  arm64: Add ASM_BUG()
2017-08-09 15:37:49 +01:00
Ard Biesheuvel
7326749801 arm64: unwind: reference pt_regs via embedded stack frame
As it turns out, the unwind code is slightly broken, and probably has
been for a while. The problem is in the dumping of the exception stack,
which is intended to dump the contents of the pt_regs struct at each
level in the call stack where an exception was taken and routed to a
routine marked as __exception (which means its stack frame is right
below the pt_regs struct on the stack).

'Right below the pt_regs struct' is ill defined, though: the unwind
code assigns 'frame pointer + 0x10' to the .sp member of the stackframe
struct at each level, and dump_backtrace() happily dereferences that as
the pt_regs pointer when encountering an __exception routine. However,
the actual size of the stack frame created by this routine (which could
be one of many __exception routines we have in the kernel) is not known,
and so frame.sp is pretty useless to figure out where struct pt_regs
really is.

So it seems the only way to ensure that we can find our struct pt_regs
when walking the stack frames is to put it at a known fixed offset of
the stack frame pointer that is passed to such __exception routines.
The simplest way to do that is to put it inside pt_regs itself, which is
the main change implemented by this patch. As a bonus, doing this allows
us to get rid of a fair amount of cruft related to walking from one stack
to the other, which is especially nice since we intend to introduce yet
another stack for overflow handling once we add support for vmapped
stacks. It also fixes an inconsistency where we only add a stack frame
pointing to ELR_EL1 if we are executing from the IRQ stack but not when
we are executing from the task stack.

To consistly identify exceptions regs even in the presence of exceptions
taken from entry code, we must check whether the next frame was created
by entry text, rather than whether the current frame was crated by
exception text.

To avoid backtracing using PCs that fall in the idmap, or are controlled
by userspace, we must explcitly zero the FP and LR in startup paths, and
must ensure that the frame embedded in pt_regs is zeroed upon entry from
EL0. To avoid these NULL entries showin in the backtrace, unwind_frame()
is updated to avoid them.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
[Mark: compare current frame against .entry.text, avoid bogus PCs]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
2017-08-09 14:07:13 +01:00
Robin Murphy
d46befef4c arm64: Convert __inval_cache_range() to area-based
__inval_cache_range() is already the odd one out among our data cache
maintenance routines as the only remaining range-based one; as we're
going to want an invalidation routine to call from C code for the pmem
API, let's tweak the prototype and name to bring it in line with the
clean operations, and to make its relationship with __dma_inv_area()
neatly mirror that of __clean_dcache_area_poc() and __dma_clean_area().
The loop clearing the early page tables gets mildly massaged in the
process for the sake of consistency.

Reviewed-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-08-09 11:00:23 +01:00
Catalin Marinas
dffb0113d5 Merge branch 'arm64/common-sysreg' of git://git.kernel.org/pub/scm/linux/kernel/git/mark/linux into for-next/core
* 'arm64/common-sysreg' of git://git.kernel.org/pub/scm/linux/kernel/git/mark/linux:
  arm64: sysreg: add Set/Way sys encodings
  arm64: sysreg: add register encodings used by KVM
  arm64: sysreg: add physical timer registers
  arm64: sysreg: subsume GICv3 sysreg definitions
  arm64: sysreg: add performance monitor registers
  arm64: sysreg: add debug system registers
  arm64: sysreg: sort by encoding
2017-04-04 18:08:47 +01:00
Ard Biesheuvel
99922257cf arm64: efi: clean up Image header after PE header has been split off
After having split off the PE header, clean up the bits that remain:
use .long consistently, merge two adjacent #ifdef CONFIG_EFI blocks,
fix the offset of the PE header pointer and remove the redundant .align
that follows it.

Also, since we will be eliminating all open coded constants from the
EFI header in subsequent patches, let's replace the open coded "ARM\x64"
magic number with its .ascii equivalent.

No changes to the resulting binary image are intended.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-04-04 17:50:28 +01:00
Ard Biesheuvel
b5f4a214b8 arm64: efi: move EFI header and related data to a separate .S file
In preparation of yet another round of modifications to the PE/COFF
header, macroize it and move the definition into a separate source
file.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-04-04 17:50:09 +01:00
Mark Rutland
d61c97a777 arm64: move !VHE work to end of el2_setup
We only need to initialise sctlr_el1 if we're installing an EL2 stub, so
we may as well defer this until we're doing so. Similarly, we can defer
intialising CPTR_EL2 until then, as we do not access any trapped
functionality as part of el2_setup.

This patch modified el2_setup accordingly, allowing us to remove a
branch and simplify the code flow.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-03-22 17:21:38 +00:00
Mark Rutland
3ad47d055a arm64: reduce el2_setup branching
The early el2_setup code is a little convoluted, with two branches where
one would do. This makes the code more painful to read than is
necessary.

We can remove a branch and simplify the logic by moving the early return
in the booted-at-EL1 case earlier in the function. This separates it
from all the setup logic that only makes sense for EL2.

Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-03-22 17:21:38 +00:00
Mark Rutland
0e9884fe63 arm64: sysreg: subsume GICv3 sysreg definitions
Unlike most sysreg defintiions, the GICv3 definitions don't have a SYS_
prefix, and they don't live in <asm/sysreg.h>. Additionally, some
definitions are duplicated elsewhere (e.g. in the KVM save/restore
code).

For consistency, and to make it possible to share a common definition
for these sysregs, this patch moves the definitions to <asm/sysreg.h>,
adding a SYS_ prefix, and sorting the registers per their encoding.
Existing users of the definitions are fixed up so that this change is
not problematic.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
2017-03-09 15:29:45 +00:00
Will Deacon
2bf47e1946 arm64: head.S: Enable EL1 (host) access to SPE when entered at EL2
The SPE architecture requires each exception level to enable access
to the SPE controls for the exception level below it, since additional
context-switch logic may be required to handle the buffer safely.

This patch allows EL1 (host) access to the SPE controls when entered at
EL2.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-02-09 18:31:25 +00:00
Ard Biesheuvel
757b435aaa efi: arm64: Add vmlinux debug link to the Image binary
When building with debugging symbols, take the absolute path to the
vmlinux binary and add it to the special PE/COFF debug table entry.
This allows a debug EFI build to find the vmlinux binary, which is
very helpful in debugging, given that the offset where the Image is
first loaded by EFI is highly unpredictable.

On implementations of UEFI that choose to implement it, this
information is exposed via the EFI debug support table, which is a UEFI
configuration table that is accessible both by the firmware at boot time
and by the OS at runtime, and lists all PE/COFF images loaded by the
system.

The format of the NB10 Codeview entry is based on the definition used
by EDK2, which is our primary reference when it comes to the use of
PE/COFF in the context of UEFI firmware.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
[will: use realpath instead of shell invocation, as discussed on list]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-02-03 15:22:37 +00:00
Mark Rutland
9bb003600e arm64: head.S: avoid open-coded adr_l
Some places in the kernel open-code sequences using ADRP for a symbol
another instruction using a :lo12: relocation for that same symbol.
These sequences are easy to get wrong, and more painful to read than is
necessary. For these reasons, it is preferable to use the
{adr,ldr,str}_l macros for these cases.

This patch makes use of adr_l these in head.S, removing an open-coded
sequence using adrp.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-01-17 17:41:02 +00:00
Mark Rutland
510224c2b1 arm64: head.S: fix up stale comments
In commit 23c8a500c2 ("arm64: kernel: use ordinary return/argument
register for el2_setup()"), we stopped using w20 as a global stash of
the boot mode flag, and instead pass this around in w0 as a function
parameter.

Unfortunately, we missed a couple of comments, which still refer to the
old convention of using w20/x20.

This patch fixes up the comments to describe the code as it currently
works.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-01-10 12:36:22 +00:00
Jintack
1650ac49c2 arm64: head.S: Fix CNTHCTL_EL2 access on VHE system
Bit positions of CNTHCTL_EL2 are changing depending on HCR_EL2.E2H bit.
EL1PCEN and EL1PCTEN are 1st and 0th bits when E2H is not set, but they
are 11th and 10th bits respectively when E2H is set.  Current code is
unintentionally setting wrong bits to CNTHCTL_EL2 with E2H set.

In fact, we don't need to set those two bits, which allow EL1 and EL0 to
access physical timer and counter respectively, if E2H and TGE are set
for the host kernel. They will be configured later as necessary. First,
we don't need to configure those bits for EL1, since the host kernel
runs in EL2.  It is a hypervisor's responsibility to configure them
before entering a VM, which runs in EL0 and EL1. Second, EL0 accesses
are configured in the later stage of boot process.

Signed-off-by: Jintack Lim <jintack@cs.columbia.edu>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-11-29 11:37:05 +00:00
Catalin Marinas
4b65a5db36 arm64: Introduce uaccess_{disable,enable} functionality based on TTBR0_EL1
This patch adds the uaccess macros/functions to disable access to user
space by setting TTBR0_EL1 to a reserved zeroed page. Since the value
written to TTBR0_EL1 must be a physical address, for simplicity this
patch introduces a reserved_ttbr0 page at a constant offset from
swapper_pg_dir. The uaccess_disable code uses the ttbr1_el1 value
adjusted by the reserved_ttbr0 offset.

Enabling access to user is done by restoring TTBR0_EL1 with the value
from the struct thread_info ttbr0 variable. Interrupts must be disabled
during the uaccess_ttbr0_enable code to ensure the atomicity of the
thread_info.ttbr0 read and TTBR0_EL1 write. This patch also moves the
get_thread_info asm macro from entry.S to assembler.h for reuse in the
uaccess_ttbr0_* macros.

Cc: Will Deacon <will.deacon@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-11-21 18:48:53 +00:00
Mark Rutland
c02433dd6d arm64: split thread_info from task stack
This patch moves arm64's struct thread_info from the task stack into
task_struct. This protects thread_info from corruption in the case of
stack overflows, and makes its address harder to determine if stack
addresses are leaked, making a number of attacks more difficult. Precise
detection and handling of overflow is left for subsequent patches.

Largely, this involves changing code to store the task_struct in sp_el0,
and acquire the thread_info from the task struct. Core code now
implements current_thread_info(), and as noted in <linux/sched.h> this
relies on offsetof(task_struct, thread_info) == 0, enforced by core
code.

This change means that the 'tsk' register used in entry.S now points to
a task_struct, rather than a thread_info as it used to. To make this
clear, the TI_* field offsets are renamed to TSK_TI_*, with asm-offsets
appropriately updated to account for the structural change.

Userspace clobbers sp_el0, and we can no longer restore this from the
stack. Instead, the current task is cached in a per-cpu variable that we
can safely access from early assembly as interrupts are disabled (and we
are thus not preemptible).

Both secondary entry and idle are updated to stash the sp and task
pointer separately.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Laura Abbott <labbott@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: James Morse <james.morse@arm.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-11-11 18:25:46 +00:00
Marc Zyngier
850540351b arm64: kernel: Init MDCR_EL2 even in the absence of a PMU
Commit f436b2ac90 ("arm64: kernel: fix architected PMU registers
unconditional access") made sure we wouldn't access unimplemented
PMU registers, but also left MDCR_EL2 uninitialized in that case,
leading to trap bits being potentially left set.

Make sure we always write something in that register.

Fixes: f436b2ac90 ("arm64: kernel: fix architected PMU registers unconditional access")
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-10-17 15:54:30 +01:00
Ard Biesheuvel
a9be2ee093 arm64: head.S: document the use of callee saved registers
Now that the only remaining occurrences of the use of callee saved
registers are on the primary boot path, add a comment to the code
which register is used for what.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-02 11:47:51 +01:00
Ard Biesheuvel
60699ba18b arm64: head.S: use ordinary stack frame for __primary_switched()
Instead of stashing the value of the link register in x28 before setting
up the stack and calling into C code, create an ordinary PCS compatible
stack frame so that we can push the return address onto the stack.

Since exception handlers require a stack as well, assign the stack pointer
register before installing the vector table.

Note that this accounts for the difference between THREAD_START_SP and
THREAD_SIZE, given that the stack pointer is always decremented before
calling into any C code.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-02 11:47:51 +01:00
Ard Biesheuvel
b929fe320e arm64: kernel: drop use of x24 from primary boot path
Keeping __PHYS_OFFSET in x24 is actually less clear than simply taking
the value of __PHYS_OFFSET using an adrp instruction in the three places
that we need it. So change that.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-02 11:47:51 +01:00
Ard Biesheuvel
9dcf7914ae arm64: kernel: use x30 for __enable_mmu return address
Using x27 for passing to __enable_mmu what is essentially the return
address makes the code look more complicated than it needs to be. So
switch to x30/lr, and update the secondary and cpu_resume call sites to
simply call __enable_mmu as an ordinary function, with a bl instruction.
This requires the callers to be covered by .idmap.text.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-02 11:47:51 +01:00
Ard Biesheuvel
3c5e9f238b arm64: head.S: move KASLR processing out of __enable_mmu()
The KASLR processing is only used by the primary boot path, and
complements the processing that takes place in __primary_switch().
Move the two parts together, to make the code easier to understand.

Also, fix up a minor whitespace issue.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
[will: fixed conflict with -rc3 due to lack of fd363bd417]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-02 11:30:13 +01:00
Ard Biesheuvel
23c8a500c2 arm64: kernel: use ordinary return/argument register for el2_setup()
The function el2_setup() passes its return value in register w20, and
in the two cases where the caller actually cares about this return value,
it is passed into set_cpu_boot_mode_flag() [almost] directly, which
expects its input in w20 as well.

So there is no reason to use a 'special' callee saved register here, but
we can simply follow the PCS for return value and first argument,
respectively.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-02 11:21:15 +01:00
James Morse
b611303811 arm64: vmlinux.ld: Add mmuoff data sections and move mmuoff text into idmap
Resume from hibernate needs to clean any text executed by the kernel with
the MMU off to the PoC. Collect these functions together into the
.idmap.text section as all this code is tightly coupled and also needs
the same cleaning after resume.

Data is more complicated, secondary_holding_pen_release is written with
the MMU on, clean and invalidated, then read with the MMU off. In contrast
__boot_cpu_mode is written with the MMU off, the corresponding cache line
is invalidated, so when we read it with the MMU on we don't get stale data.
These cache maintenance operations conflict with each other if the values
are within a Cache Writeback Granule (CWG) of each other.
Collect the data into two sections .mmuoff.data.read and .mmuoff.data.write,
the linker script ensures mmuoff.data.write section is aligned to the
architectural maximum CWG of 2KB.

Signed-off-by: James Morse <james.morse@arm.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-08-25 18:00:30 +01:00
Ard Biesheuvel
aea73abb90 arm64: head.S: get rid of x25 and x26 with 'global' scope
Currently, x25 and x26 hold the physical addresses of idmap_pg_dir
and swapper_pg_dir, respectively, when running early boot code. But
having registers with 'global' scope in files that contain different
sections with different lifetimes, and that are called by different
CPUs at different times is a bit messy, especially since stashing the
values does not buy us anything in terms of code size or clarity.

So simply replace each reference to x25 or x26 with an adrp instruction
referring to idmap_pg_dir or swapper_pg_dir directly.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-08-22 14:25:15 +01:00
Ard Biesheuvel
08cc55b2af arm64: relocatable: suppress R_AARCH64_ABS64 relocations in vmlinux
The linker routines that we rely on to produce a relocatable PIE binary
treat it as a shared ELF object in some ways, i.e., it emits symbol based
R_AARCH64_ABS64 relocations into the final binary since doing so would be
appropriate when linking a shared library that is subject to symbol
preemption. (This means that an executable can override certain symbols
that are exported by a shared library it is linked with, and that the
shared library *must* update all its internal references as well, and point
them to the version provided by the executable.)

Symbol preemption does not occur for OS hosted PIE executables, let alone
for vmlinux, and so we would prefer to get rid of these symbol based
relocations. This would allow us to simplify the relocation routines, and
to strip the .dynsym, .dynstr and .hash sections from the binary. (Note
that these are tiny, and are placed in the .init segment, but they clutter
up the vmlinux binary.)

Note that these R_AARCH64_ABS64 relocations are only emitted for absolute
references to symbols defined in the linker script, all other relocatable
quantities are covered by anonymous R_AARCH64_RELATIVE relocations that
simply list the offsets to all 64-bit values in the binary that need to be
fixed up based on the offset between the link time and run time addresses.

Fortunately, GNU ld has a -Bsymbolic option, which is intended for shared
libraries to allow them to ignore symbol preemption, and unconditionally
bind all internal symbol references to its own definitions. So set it for
our PIE binary as well, and get rid of the asoociated sections and the
relocation code that processes them.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
[will: fixed conflict with __dynsym_offset linker script entry]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-07-29 10:45:01 +01:00
Linus Torvalds
be092017b6 arm64 updates for 4.7:
- virt_to_page/page_address optimisations
 
 - Support for NUMA systems described using device-tree
 
 - Support for hibernate/suspend-to-disk
 
 - Proper support for maxcpus= command line parameter
 
 - Detection and graceful handling of AArch64-only CPUs
 
 - Miscellaneous cleanups and non-critical fixes
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Will Deacon:

 - virt_to_page/page_address optimisations

 - support for NUMA systems described using device-tree

 - support for hibernate/suspend-to-disk

 - proper support for maxcpus= command line parameter

 - detection and graceful handling of AArch64-only CPUs

 - miscellaneous cleanups and non-critical fixes

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (92 commits)
  arm64: do not enforce strict 16 byte alignment to stack pointer
  arm64: kernel: Fix incorrect brk randomization
  arm64: cpuinfo: Missing NULL terminator in compat_hwcap_str
  arm64: secondary_start_kernel: Remove unnecessary barrier
  arm64: Ensure pmd_present() returns false after pmd_mknotpresent()
  arm64: Replace hard-coded values in the pmd/pud_bad() macros
  arm64: Implement pmdp_set_access_flags() for hardware AF/DBM
  arm64: Fix typo in the pmdp_huge_get_and_clear() definition
  arm64: mm: remove unnecessary EXPORT_SYMBOL_GPL
  arm64: always use STRICT_MM_TYPECHECKS
  arm64: kvm: Fix kvm teardown for systems using the extended idmap
  arm64: kaslr: increase randomization granularity
  arm64: kconfig: drop CONFIG_RTC_LIB dependency
  arm64: make ARCH_SUPPORTS_DEBUG_PAGEALLOC depend on !HIBERNATION
  arm64: hibernate: Refuse to hibernate if the boot cpu is offline
  arm64: kernel: Add support for hibernate/suspend-to-disk
  PM / Hibernate: Call flush_icache_range() on pages restored in-place
  arm64: Add new asm macro copy_page
  arm64: Promote KERNEL_START/KERNEL_END definitions to a header file
  arm64: kernel: Include _AC definition in page.h
  ...
2016-05-16 17:17:24 -07:00
James Morse
28c7258330 arm64: Promote KERNEL_START/KERNEL_END definitions to a header file
KERNEL_START and KERNEL_END are useful outside head.S, move them to a
header file.

Signed-off-by: James Morse <james.morse@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-04-28 12:05:46 +01:00