mirror_ubuntu-kernels/arch/x86/kernel
Chang S. Bae db8268df09 x86/arch_prctl: Add controls for dynamic XSTATE components
Dynamically enabled XSTATE features are by default disabled for all
processes. A process has to request permission to use such a feature.

To support this implement a architecture specific prctl() with the options:

   - ARCH_GET_XCOMP_SUPP

     Copies the supported feature bitmap into the user space provided
     u64 storage. The pointer is handed in via arg2

   - ARCH_GET_XCOMP_PERM

     Copies the process wide permitted feature bitmap into the user space
     provided u64 storage. The pointer is handed in via arg2

   - ARCH_REQ_XCOMP_PERM

     Request permission for a feature set. A feature set can be mapped to a
     facility, e.g. AMX, and can require one or more XSTATE components to
     be enabled.

     The feature argument is the number of the highest XSTATE component
     which is required for a facility to work.

     The request argument is not a user supplied bitmap because that makes
     filtering harder (think seccomp) and even impossible because to
     support 32bit tasks the argument would have to be a pointer.

The permission mechanism works this way:

   Task asks for permission for a facility and kernel checks whether that's
   supported. If supported it does:

     1) Check whether permission has already been granted

     2) Compute the size of the required kernel and user space buffer
        (sigframe) size.

     3) Validate that no task has a sigaltstack installed
        which is smaller than the resulting sigframe size

     4) Add the requested feature bit(s) to the permission bitmap of
        current->group_leader->fpu and store the sizes in the group
        leaders fpu struct as well.

If that is successful then the feature is still not enabled for any of the
tasks. The first usage of a related instruction will result in a #NM
trap. The trap handler validates the permission bit of the tasks group
leader and if permitted it installs a larger kernel buffer and transfers
the permission and size info to the new fpstate container which makes all
the FPU functions which require per task information aware of the extended
feature set.

  [ tglx: Adopted to new base code, added missing serialization,
          massaged namings, comments and changelog ]

Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20211021225527.10184-7-chang.seok.bae@intel.com
2021-10-26 10:18:09 +02:00
..
acpi x86: Fix typo s/ECLR/ELCR/ for the PIC register 2021-08-10 23:31:44 +02:00
apic A set of updates to support port 0x22/0x23 based PCI configuration space 2021-08-30 15:20:05 -07:00
cpu x86/fpu: Replace the includes of fpu/internal.h 2021-10-20 15:27:29 +02:00
fpu x86/arch_prctl: Add controls for dynamic XSTATE components 2021-10-26 10:18:09 +02:00
kprobes Merge branch 'akpm' (patches from Andrew) 2021-07-02 12:08:10 -07:00
.gitignore
alternative.c Linux 5.13-rc5 2021-06-07 11:02:30 +02:00
amd_gart_64.c x86/amd_gart: don't set failed sg dma_address to DMA_MAPPING_ERROR 2021-08-09 17:13:06 +02:00
amd_nb.c hwmon: (k10temp) Add support for yellow carp 2021-08-27 13:54:58 -07:00
aperture_64.c memblock: make memblock_find_in_range method private 2021-09-03 09:58:17 -07:00
apm_32.c x86: Fix various typos in comments, take #2 2021-03-21 23:50:28 +01:00
asm-offsets_32.c x86/stackprotector/32: Make the canary into a regular percpu variable 2021-03-08 13:19:05 +01:00
asm-offsets_64.c x86/xen: Drop USERGS_SYSRET64 paravirt call 2021-02-10 12:32:07 +01:00
asm-offsets.c x86/paravirt: Switch iret pvops to ALTERNATIVE 2021-03-11 19:58:54 +01:00
audit_64.c x86/audit: Fix a -Wmissing-prototypes warning for ia32_classify_syscall() 2020-05-19 18:03:07 +02:00
bootflag.c
check.c
cpuid.c smp: Cleanup smp_call_function*() 2020-11-24 16:47:49 +01:00
crash_core_32.c mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
crash_core_64.c mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
crash_dump_32.c x86/crashdump/32: Simplify copy_oldmem_page() 2020-11-24 14:42:09 +01:00
crash_dump_64.c
crash.c x86/crash: Remove crash_reserve_low_1M() 2021-06-07 12:14:45 +02:00
devicetree.c x86/devicetree: Fix the ioapic interrupt type table 2020-10-28 20:26:24 +01:00
doublefault_32.c x86/stackprotector/32: Make the canary into a regular percpu variable 2021-03-08 13:19:05 +01:00
dumpstack_32.c
dumpstack_64.c x86/irq/64: Adjust the per CPU irq stack pointer by 8 2021-02-10 23:34:14 +01:00
dumpstack.c x86/dumpstack: use %pSb/%pBb for backtrace printing 2021-07-08 11:48:22 -07:00
e820.c Power management updates for 5.13-rc1 2021-04-26 15:10:25 -07:00
early_printk.c mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
early-quirks.c x86/hpet: Use another crystalball to evaluate HPET usability 2021-10-01 13:38:13 +02:00
ebda.c
eisa.c
espfix_64.c mm: introduce include/linux/pgtable.h 2020-06-09 09:39:13 -07:00
ftrace_32.S x86: Change {JMP,CALL}_NOSPEC argument 2020-04-30 20:14:34 +02:00
ftrace_64.S x86/ftrace: Support objtool vmlinux.o validation in ftrace_64.S 2021-01-26 11:33:02 -06:00
ftrace.c x86: Remove dynamic NOP selection 2021-03-15 16:24:59 +01:00
head32.c
head64.c x86/sev-es: Rename sev-es.{ch} to sev.{ch} 2021-05-10 07:40:27 +02:00
head_32.S printk: Userspace format indexing support 2021-07-19 11:57:48 +02:00
head_64.S x86/entry: Unify definitions from <asm/calling.h> and <asm/ptrace-abi.h> 2021-05-12 10:49:13 +02:00
hpet.c x86/hpet: Use another crystalball to evaluate HPET usability 2021-10-01 13:38:13 +02:00
hw_breakpoint.c x86/debug: Prevent data breakpoints on cpu_dr7 2021-02-05 20:13:12 +01:00
i8237.c
i8253.c
i8259.c x86: Avoid magic number with ELCR register accesses 2021-08-10 23:31:43 +02:00
idt.c X86 interrupt related changes: 2021-06-29 12:36:59 -07:00
io_delay.c
ioport.c x86/ioperm: Prevent a memory leak when fork fails 2020-05-28 21:36:20 +02:00
irq_32.c softirq: Move do_softirq_own_stack() to generic asm header 2021-02-10 23:34:16 +01:00
irq_64.c x86/softirq/64: Inline do_softirq_own_stack() 2021-02-10 23:34:17 +01:00
irq_work.c x86/entry: Convert various system vectors 2020-06-11 15:15:14 +02:00
irq.c x86: Fix various typos in comments 2021-03-18 15:31:53 +01:00
irqflags.S x86/pv: Rework arch_local_irq_restore() to not use popf 2021-02-10 12:36:45 +01:00
irqinit.c x86/headers: Remove APIC headers from <asm/smp.h> 2020-08-06 16:13:09 +02:00
itmt.c sysctl: pass kernel pointers to ->proc_handler 2020-04-27 02:07:40 -04:00
jailhouse.c locking/seqlock, headers: Untangle the spaghetti monster 2020-08-06 16:13:13 +02:00
jump_label.c jump_labels: Mark __jump_label_transform() as __always_inlined to work around aggressive compiler un-inlining 2021-07-13 06:32:05 +02:00
kdebugfs.c
kexec-bzimage64.c x86: Use ELF fields defined in 'struct kimage' 2021-03-08 12:06:29 -07:00
kgdb.c x86: Fix various typos in comments 2021-03-18 15:31:53 +01:00
ksysfs.c
kvm.c x86/kvm: Don't enable IRQ when IRQ enabled in kvm_wait 2021-09-06 06:32:35 -04:00
kvmclock.c x86/kvmclock: Move this_cpu_pvti into kvmclock.h 2021-09-30 04:08:01 -04:00
ldt.c memcg: enable accounting for ldt_struct objects 2021-09-03 09:58:13 -07:00
machine_kexec_32.c x86/kexec: Set_[gi]dt() -> native_[gi]dt_invalidate() in machine_kexec_*.c 2021-05-21 12:36:45 +02:00
machine_kexec_64.c x86/kexec: Set_[gi]dt() -> native_[gi]dt_invalidate() in machine_kexec_*.c 2021-05-21 12:36:45 +02:00
Makefile drm-misc-next for v5.15-rc1: 2021-07-23 11:32:43 +10:00
mmconf-fam10h_64.c x86/msr: Rename MSR_K8_SYSCFG to MSR_AMD64_SYSCFG 2021-05-10 07:51:38 +02:00
module.c x86/build: Treat R_386_PLT32 relocation as R_386_PC32 2021-01-28 12:24:06 +01:00
mpparse.c x86: Avoid magic number with ELCR register accesses 2021-08-10 23:31:43 +02:00
msr.c x86/MSR: Filter MSR writes through X86_IOC_WRMSR_REGS ioctl too 2021-01-27 19:06:47 +01:00
nmi_selftest.c
nmi.c x86/sev-es: Rename sev-es.{ch} to sev.{ch} 2021-05-10 07:40:27 +02:00
paravirt-spinlocks.c x86/paravirt: Add new features for paravirt patching 2021-03-11 19:51:49 +01:00
paravirt.c The x86 MM changes in this cycle were: 2021-04-29 11:41:43 -07:00
pci-dma.c dma-mapping: move dma-debug.h to kernel/dma/ 2020-10-06 07:07:05 +02:00
pci-iommu_table.c x86: Remove definition of DEBUG 2021-01-15 08:23:10 +01:00
pci-swiotlb.c
pcspeaker.c
perf_regs.c - Remove all uses of TIF_IA32 and TIF_X32 and reclaim the two bits in the end 2020-12-14 13:45:26 -08:00
platform-quirks.c
pmem.c
probe_roms.c maccess: make get_kernel_nofault() check for minimal type compatibility 2020-06-18 12:10:37 -07:00
process_32.c x86/fpu: Move context switch and exit to user inlines into sched.h 2021-10-20 15:27:27 +02:00
process_64.c x86/fpu: Move context switch and exit to user inlines into sched.h 2021-10-20 15:27:27 +02:00
process.c x86/arch_prctl: Add controls for dynamic XSTATE components 2021-10-26 10:18:09 +02:00
process.h
ptrace.c x86/fpu: Remove internal.h dependency from fpu/signal.h 2021-10-20 15:27:29 +02:00
pvclock.c x86: Fix various typos in comments 2021-03-18 15:31:53 +01:00
quirks.c x86, powerpc: Rename memcpy_mcsafe() to copy_mc_to_{user, kernel}() 2020-10-06 11:18:04 +02:00
reboot_fixups_32.c
reboot.c x86/reboot: Limit Dell Optiplex 990 quirk to early BIOS versions 2021-08-12 12:06:58 +02:00
relocate_kernel_32.S x86: Fix various typos in comments, take #2 2021-03-21 23:50:28 +01:00
relocate_kernel_64.S x86: Fix various typos in comments, take #2 2021-03-21 23:50:28 +01:00
resource.c
rtc.c
setup_percpu.c memblock: introduce saner 'memblock_free_ptr()' interface 2021-09-14 13:23:22 -07:00
setup.c x86/setup: Call early_reserve_memory() earlier 2021-09-21 09:52:08 +02:00
sev_verify_cbit.S x86/boot/compressed/64: Check SEV encryption in 64-bit boot-path 2020-10-29 18:06:52 +01:00
sev-shared.c x86/sev: Return an error on a returned non-zero SW_EXITINFO1[31:0] 2021-10-01 11:14:41 +02:00
sev.c x86/sev: Include fpu/xcr.h 2021-10-20 15:27:29 +02:00
signal_compat.c signal: Verify the alignment and size of siginfo_t 2021-07-23 13:15:31 -05:00
signal.c x86/signal: Implement sigaltstack size validation 2021-10-26 10:18:09 +02:00
smp.c x86: Fix various typos in comments, take #2 2021-03-21 23:50:28 +01:00
smpboot.c x86/fpu: Replace the includes of fpu/internal.h 2021-10-20 15:27:29 +02:00
stacktrace.c stacktrace: Move documentation for arch_stack_walk_reliable() to header 2021-03-10 15:52:31 +01:00
static_call.c x86: Remove dynamic NOP selection 2021-03-15 16:24:59 +01:00
step.c entry: Ensure trap after single-step on system call return 2021-02-06 00:21:42 +01:00
sys_ia32.c x86: switch to kernel_clone() 2020-08-20 13:12:58 +02:00
sys_x86_64.c x86/mm: Refine mmap syscall implementation 2021-01-05 19:07:42 +01:00
tboot.c x86/boot/tboot: Avoid Wstringop-overread-warning 2021-03-23 00:16:13 +01:00
time.c A set of fixes and updates for x86: 2020-06-11 15:54:31 -07:00
tls.c x86/stackprotector/32: Make the canary into a regular percpu variable 2021-03-08 13:19:05 +01:00
tls.h x86: switch to ->regset_get() 2020-07-27 14:31:07 -04:00
topology.c x86: Fix various typos in comments 2021-03-18 15:31:53 +01:00
trace_clock.c
trace.c trace/osnoise: Fix 'no previous prototype' warnings 2021-06-28 14:12:26 -04:00
tracepoint.c x86/entry: Convert reschedule interrupt to IDTENTRY_SYSVEC_SIMPLE 2020-06-11 15:15:16 +02:00
traps.c x86/fpu: Replace the includes of fpu/internal.h 2021-10-20 15:27:29 +02:00
tsc_msr.c Misc fixes and small updates all around the place: 2020-08-15 10:38:03 -07:00
tsc_sync.c x86: Fix various typos in comments, take #2 2021-03-21 23:50:28 +01:00
tsc.c clocksource: Reduce clocksource-skew threshold 2021-06-22 16:53:16 +02:00
umip.c x86/insn: Extend error reporting from insn_fetch_from_user[_inatomic]() 2021-06-15 11:39:30 +02:00
unwind_frame.c fork-v5.9 2020-08-04 14:47:45 -07:00
unwind_guess.c
unwind_orc.c x86/unwind/orc: Silence warnings caused by missing ORC data 2021-03-06 13:09:45 +01:00
uprobes.c x86/uprobes: Convert to insn_decode() 2021-03-15 12:05:03 +01:00
verify_cpu.S
vm86_32.c x86/vm86/32: Remove VM86_SCREEN_BITMAP support 2021-01-21 20:08:53 +01:00
vmlinux.lds.S x86/build: Fix vmlinux size check on 64-bit 2020-10-29 21:54:35 +01:00
vsmp_64.c
x86_init.c x86/apic: Support 15 bits of APIC ID in MSI where available 2020-10-28 20:26:29 +01:00