Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.
It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access. But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.
A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model. And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.
This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.
There were a couple of notable cases:
- csky still had the old "verify_area()" name as an alias.
- the iter_iov code had magical hardcoded knowledge of the actual
values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
really used it)
- microblaze used the type argument for a debug printout
but other than those oddities this should be a total no-op patch.
I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something. Any missed conversion should be trivially fixable, though.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In arm_notify_die call force_sig_fault to let the generic
code handle siginfo generation.
This removes some boiler plate making the code easier to
maintain in the long run.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Pull siginfo updates from Eric Biederman:
"This set of changes close the known issues with setting si_code to an
invalid value, and with not fully initializing struct siginfo. There
remains work to do on nds32, arc, unicore32, powerpc, arm, arm64, ia64
and x86 to get the code that generates siginfo into a simpler and more
maintainable state. Most of that work involves refactoring the signal
handling code and thus careful code review.
Also not included is the work to shrink the in kernel version of
struct siginfo. That depends on getting the number of places that
directly manipulate struct siginfo under control, as it requires the
introduction of struct kernel_siginfo for the in kernel things.
Overall this set of changes looks like it is making good progress, and
with a little luck I will be wrapping up the siginfo work next
development cycle"
* 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (46 commits)
signal/sh: Stop gcc warning about an impossible case in do_divide_error
signal/mips: Report FPE_FLTUNK for undiagnosed floating point exceptions
signal/um: More carefully relay signals in relay_signal.
signal: Extend siginfo_layout with SIL_FAULT_{MCEERR|BNDERR|PKUERR}
signal: Remove unncessary #ifdef SEGV_PKUERR in 32bit compat code
signal/signalfd: Add support for SIGSYS
signal/signalfd: Remove __put_user from signalfd_copyinfo
signal/xtensa: Use force_sig_fault where appropriate
signal/xtensa: Consistenly use SIGBUS in do_unaligned_user
signal/um: Use force_sig_fault where appropriate
signal/sparc: Use force_sig_fault where appropriate
signal/sparc: Use send_sig_fault where appropriate
signal/sh: Use force_sig_fault where appropriate
signal/s390: Use force_sig_fault where appropriate
signal/riscv: Replace do_trap_siginfo with force_sig_fault
signal/riscv: Use force_sig_fault where appropriate
signal/parisc: Use force_sig_fault where appropriate
signal/parisc: Use force_sig_mceerr where appropriate
signal/openrisc: Use force_sig_fault where appropriate
signal/nios2: Use force_sig_fault where appropriate
...
Prohibit kprobes on do_undefinstr because kprobes on
arm is implemented by undefined instruction. This means
if we probe do_undefinstr(), it can cause infinit
recursive exception.
Fixes: 24ba613c9d ("ARM kprobes: core code")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Call clear_siginfo to ensure every stack allocated siginfo is properly
initialized before being passed to the signal sending functions.
Note: It is not safe to depend on C initializers to initialize struct
siginfo on the stack because C is allowed to skip holes when
initializing a structure.
The initialization of struct siginfo in tracehook_report_syscall_exit
was moved from the helper user_single_step_siginfo into
tracehook_report_syscall_exit itself, to make it clear that the local
variable siginfo gets fully initialized.
In a few cases the scope of struct siginfo has been reduced to make it
clear that siginfo siginfo is not used on other paths in the function
in which it is declared.
Instances of using memset to initialize siginfo have been replaced
with calls clear_siginfo for clarity.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Pull ARM updates from Russell King:
- StrongARM SA1111 updates to modernise and remove cruft
- Add StrongARM gpio drivers for board GPIOs
- Verify size of zImage is what we expect to avoid issues with
appended DTB
- nommu updates from Vladimir Murzin
- page table read-write-execute checking from Jinbum Park
- Broadcom Brahma-B15 cache updates from Florian Fainelli
- Avoid failure with kprobes test caused by inappropriately
placed kprobes
- Remove __memzero optimisation (which was incorrectly being
used directly by some drivers)
* 'for-linus' of git://git.armlinux.org.uk/~rmk/linux-arm: (32 commits)
ARM: 8745/1: get rid of __memzero()
ARM: 8744/1: don't discard memblock for kexec
ARM: 8743/1: bL_switcher: add MODULE_LICENSE tag
ARM: 8742/1: Always use REFCOUNT_FULL
ARM: 8741/1: B15: fix unused label warnings
ARM: 8740/1: NOMMU: Make sure we do not hold stale data in mem[] array
ARM: 8739/1: NOMMU: Setup VBAR/Hivecs for secondaries cores
ARM: 8738/1: Disable CONFIG_DEBUG_VIRTUAL for NOMMU
ARM: 8737/1: mm: dump: add checking for writable and executable
ARM: 8736/1: mm: dump: make the page table dumping seq_file
ARM: 8735/1: mm: dump: make page table dumping reusable
ARM: sa1100/neponset: add GPIO drivers for control and modem registers
ARM: sa1100/assabet: add BCR/BSR GPIO driver
ARM: 8734/1: mm: idmap: Mark variables as ro_after_init
ARM: 8733/1: hw_breakpoint: Mark variables as __ro_after_init
ARM: 8732/1: NOMMU: Allow userspace to access background MPU region
ARM: 8727/1: MAINTAINERS: Update brcmstb entries to cover B15 code
ARM: 8728/1: B15: Register reboot notifier for KEXEC
ARM: 8730/1: B15: Add suspend/resume hooks
ARM: 8726/1: B15: Add CPU hotplug awareness
...
Avoid adding kprobes to any of the kernel entry/exit or startup
assembly code, or code in the identity-mapped region. This code does
not conform to the standard C conventions, which means that the
expectations of the kprobes code is not forfilled.
Placing kprobes at some of these locations results in the kernel trying
to return to userspace addresses while retaining the CPU in kernel mode.
Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
When CONFIG_DEBUG_USER is enabled, it's possible for a user to
deliberately trigger dump_instr() with a chosen kernel address.
Let's avoid problems resulting from this by using get_user() rather than
__get_user(), ensuring that we don't erroneously access kernel memory.
So that we can use the same code to dump user instructions and kernel
instructions, the common dumping code is factored out to __dump_instr(),
with the fs manipulated appropriately in dump_instr() around calls to
this.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
When there is no dedicated register to hold the tp value and no MMU
to provide a fixed address kuser helper entry point, all that is
left as fallback is a syscall.
Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Mickael GUENE <mickael.guene@st.com>
Tested-by: Vincent Abriou <vincent.abriou@st.com>
Tested-by: Andras Szemzo <szemzo.andras@gmail.com>
We are going to split <linux/sched/task_stack.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.
Create a trivial placeholder <linux/sched/task_stack.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.
Include the new header in the files that are going to need it.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We are going to split <linux/sched/debug.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.
Create a trivial placeholder <linux/sched/debug.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.
Include the new header in the files that are going to need it.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We are going to split <linux/sched/signal.h> out of <linux/sched.h>, which
will have to be picked up from other headers and a couple of .c files.
Create a trivial placeholder <linux/sched/signal.h> file that just
maps to <linux/sched.h> to make this patch obviously correct and
bisectable.
Include the new header in the files that are going to need it.
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Recent kernels have changed their behaviour to be more inconsistent
when handling printk continuations. With todays kernels, the output
looks sane on the console, but dmesg splits individual printk()s which
do not have the KERN_CONT prefix into separate lines.
Since the assembly code is not trivial to add the KERN_CONT, and we
ideally want to avoid using KERN_CONT (as multiple printk()s can race
between different threads), convert the assembly dumping the register
values to C code, and have the C code build the output a line at a
time before dumping to the console.
This avoids the KERN_CONT issue, and also avoids situations where the
output is intermixed with other console activity.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Mark Brand reports that a NEEDS_SYSCALL_FOR_CMPXCHG enabled kernel would
open a security hole in the ghost syscall used to implement cmpxchg, as
it fails to validate the user pointer.
However, in order for this option to be enabled, you'd need to be
building a pre-ARMv6 kernel with SMP support. There is only one system
known which fits that, which is an early ARM SMP FPGA implementation
based on the ARM926T.
In any case, the Kconfig does not allow SMP to be enabled for pre-ARMv6
systems.
Moreover, even if NEEDS_SYSCALL_FOR_CMPXCHG were to be enabled, the
kernel would not build as __ARM_NR_cmpxchg64 is not defined.
The simple answer is to remove the buggy code.
Reported-by: Mark Brand <markbrand@google.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Since we switched to early trap initialisation in 94e5a85b3b
("ARM: earlier initialization of vectors page") we haven't been writing
directly to the vectors page, and so there's no need for this domain
to be in manager mode. Switch it to client mode.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
As execution domain support is gone we can remove
signal translation from the signal code and remove
exec_domain from thread_info.
Signed-off-by: Richard Weinberger <richard@nod.at>
We cannot restart cacheflush safely if a process provides user-defined
signal handler and signal is pending. In this case -EINTR is returned
and it is expected that process re-invokes syscall. However, there are
a few problems with that:
* looks like nobody bothers checking return value from cacheflush
* but if it did, we don't provide the restart address for that, so the
process has to use the same range again
* ...and again, what might lead to looping forever
So, remove cacheflush restarting code and terminate cache flushing
as early as fatal signal is pending.
Cc: stable@vger.kernel.org # 3.12+
Reported-by: Chanho Min <chanho.min@lge.com>
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Convert many (but not all) printk(KERN_* to pr_* to simplify the code.
We take the opportunity to join some printk lines together so we don't
split the message across several lines, and we also add a few levels
to some messages which were previously missing them.
Tested-by: Andrew Lunn <andrew@lunn.ch>
Tested-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
do_unexp_fiq() has never been called by any code in the last 10 years,
it's about time it was removed!
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch introduces a new default FIQ handler that is structured in a
similar way to the existing ARM exception handler and result in the FIQ
being handled by C code running on the SVC stack (despite this code run
in the FIQ handler is subject to severe limitations with respect to
locking making normal interaction with the kernel impossible).
This default handler allows concepts that on x86 would be handled using
NMIs to be realized on ARM.
Credit:
This patch is a near complete re-write of a patch originally
provided by Anton Vorontsov. Today only a couple of small fragments
survive, however without Anton's work to build from this patch would
not exist. Thanks also to Russell King for spoonfeeding me a variety
of fixes during the review cycle.
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The TPIDRURO and TPIDRURW registers need to be flushed during exec;
otherwise TLS information is potentially leaked. TPIDRURO in
particular needs careful treatment. Since flush_thread basically
needs the same code used to set the TLS in arm_syscall, pull that into
a common set_tls helper in tls.h and use it in both places.
Similarly, TEEHBR needs to be cleared during exec as well. Clearing
its save slot in thread_info isn't right as there is no guarantee
that a thread switch will occur before the new program runs. Just
setting the register directly is sufficient.
Signed-off-by: Nathan Lynch <nathan_lynch@mentor.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Use the newly-introduced frame_pointer macro to extract
the correct FP based on whether we are in THUMB2 mode or not.
Signed-off-by: Nikolay Borisov <Nikolay.Borisov@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Currently code has an inverted logic: opcode from user memory
is swapped to a proper endianness only in case of read error.
While normally opcode should be swapped only if it was read
correctly from user memory.
Reviewed-by: Victor Kamensky <victor.kamensky@linaro.org>
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Taras Kondratiuk <taras.kondratiuk@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The array was missing the final entry for the undefined instruction
exception handler; this commit adds it.
Cc: <stable@vger.kernel.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
We don't need the offset for the first function name in each backtrace
entry; this needlessly consumes screen space. This is virtually always
the first or second instruction in the called function.
Also, recognise stmfd instructions which include r10 as a valid stack
saving instruction, and when dumping the registers, dump six registers
per line rather than five, and fix the wrapping.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The __do_cache_op function operates with a 'chunk' size of one page
but fails to limit the size of the final chunk so as to not exceed
the specified memory region. Fix this.
Cc: <stable@vger.kernel.org>
Reported-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Tested-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Jon Medhurst <tixy@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Fixes a harmless warning when building for V7M (!MMU):
arch/arm/kernel/traps.c:859:123: warning: 'kuser_init' defined but not used [-Wunused-function]
By making the stub static inline instead of just static.
Fixes: f6f91b0d9f ('ARM: allow kuser helpers to be removed from the vector page')
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Currently BUG() uses .word or .hword to create the necessary illegal
instructions. However if we are building BE8 then these get swapped
by the linker into different illegal instructions in the text. This
means that the BUG() macro does not get trapped properly.
Change to using <asm/opcodes.h> to provide the necessary ARM instruction
building as we cannot rely on gcc/gas having the `.inst` instructions
which where added to try and resolve this issue (reported by Dave Martin
<Dave.Martin@arm.com>).
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Reviewed-by: Dave Martin <Dave.Martin@arm.com>
The trap handler needs to take into account the endian configuration of
the system when loading instructions. Use <asm/opcodes.h> to provide the
necessary conversion functions.
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Tested-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
do_cache_op finds the lowest VMA contained in the specified address
range and rounds the range to cover only the mapped addresses.
Since commit 4542b6a0fa ("ARM: 7365/1: drop unused parameter from
flush_cache_user_range") the VMA is not used for anything else in this
code and seeing as the low-level cache flushing routines return -EFAULT
if the address is not valid, there is no need for this range truncation.
This patch removes the VMA handling code from the cacheflushing syscall.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Flushing a large, non-faulting VMA from userspace can potentially result
in a long time spent flushing the cache line-by-line without preemption
occurring (in the case of CONFIG_PREEMPT=n).
Whilst this doesn't affect the stability of the system, it can certainly
affect the responsiveness and CPU availability for other tasks.
This patch splits up the user cacheflush code so that it flushes in
chunks of a page. After each chunk has been flushed, we may reschedule
if appropriate and, before processing the next chunk, we allow any
pending signals to be handled before resuming from where we left off.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Move the signal handlers into a VDSO page rather than keeping them in
the vectors page. This allows us to place them randomly within this
page, and also map the page at a random location within userspace
further protecting these code fragments from ROP attacks. The new
VDSO page is also poisoned in the same way as the vector page.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Provide a kernel configuration option to allow the kernel user helpers
to be removed from the vector page, thereby preventing their use with
ROP (return orientated programming) attacks. This option is only
visible for CPU architectures which natively support all the operations
which kernel user helpers would normally provide, and must be enabled
with caution.
Cc: <stable@vger.kernel.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Move the machine vector stubs into the page above the vector page,
which we can prevent from being visible to userspace. Also move
the reset stub, and place the swi vector at a location that the
'ldr' can get to it.
This hides pointers into the kernel which could give valuable
information to attackers, and reduces the number of exploitable
instructions at a fixed address.
Cc: <stable@vger.kernel.org>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Fill the empty regions of the vectors page with an exception generating
instruction. This ensures that any inappropriate branch to the vector
page is appropriately trapped, rather than just encountering some code
to execute. (The vectors page was filled with zero before, which
corresponds with the "andeq r0, r0, r0" instruction - a no-op.)
Cc: <stable@vger.kernel.org>
Acked-by Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Since commit 6a1c53124a the user writeable TLS register was zeroed to
prevent it from being used as a covert channel between two tasks.
There are more and more applications coming to Windows RT,
Wine could support them, but mostly they expect to have
the thread environment block (TEB) in TPIDRURW.
This patch preserves that register per thread instead of clearing it.
Unlike the TPIDRURO, which is already switched, the TPIDRURW
can be updated from userspace so needs careful treatment in the case that we
modify TPIDRURW and call fork(). To avoid this we must always read
TPIDRURW in copy_thread.
Signed-off-by: André Hentschel <nerv@dawncrow.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Jonathan Austin <jonathan.austin@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Pull ARM-v7M support from Uwe Kleine-König:
"All but the last patch were in next since next-20130418 without issues.
The last patch fixes a problem in combination with
8164f7a (ARM: 7680/1: Detect support for SDIV/UDIV from ISAR0 register)
which triggers a WARN_ON without an implemented read_cpuid_ext.
The branch merges fine into v3.10-rc1 and I'd be happy if you pulled it
for 3.11-rc1. The only missing piece to be able to run a Cortex-M3 is
the irqchip driver that will go in via Thomas Gleixner and platform
specific stuff."
Both dump_stack() and show_stack() are currently implemented by each
architecture. show_stack(NULL, NULL) dumps the backtrace for the
current task as does dump_stack(). On some archs, dump_stack() prints
extra information - pid, utsname and so on - in addition to the
backtrace while the two are identical on other archs.
The usages in arch-independent code of the two functions indicate
show_stack(NULL, NULL) should print out bare backtrace while
dump_stack() is used for debugging purposes when something went wrong,
so it does make sense to print additional information on the task which
triggered dump_stack().
There's no reason to require archs to implement two separate but mostly
identical functions. It leads to unnecessary subtle information.
This patch expands the dummy fallback dump_stack() implementation in
lib/dump_stack.c such that it prints out debug information (taken from
x86) and invokes show_stack(NULL, NULL) and drops arch-specific
dump_stack() implementations in all archs except blackfin. Blackfin's
dump_stack() does something wonky that I don't understand.
Debug information can be printed separately by calling
dump_stack_print_info() so that arch-specific dump_stack()
implementation can still emit the same debug information. This is used
in blackfin.
This patch brings the following behavior changes.
* On some archs, an extra level in backtrace for show_stack() could be
printed. This is because the top frame was determined in
dump_stack() on those archs while generic dump_stack() can't do that
reliably. It can be compensated by inlining dump_stack() but not
sure whether that'd be necessary.
* Most archs didn't use to print debug info on dump_stack(). They do
now.
An example WARN dump follows.
WARNING: at kernel/workqueue.c:4841 init_workqueues+0x35/0x505()
Hardware name: empty
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.9.0-rc1-work+ #9
0000000000000009 ffff88007c861e08 ffffffff81c614dc ffff88007c861e48
ffffffff8108f50f ffffffff82228240 0000000000000040 ffffffff8234a03c
0000000000000000 0000000000000000 0000000000000000 ffff88007c861e58
Call Trace:
[<ffffffff81c614dc>] dump_stack+0x19/0x1b
[<ffffffff8108f50f>] warn_slowpath_common+0x7f/0xc0
[<ffffffff8108f56a>] warn_slowpath_null+0x1a/0x20
[<ffffffff8234a071>] init_workqueues+0x35/0x505
...
v2: CPU number added to the generic debug info as requested by s390
folks and dropped the s390 specific dump_stack(). This loses %ksp
from the debug message which the maintainers think isn't important
enough to keep the s390-specific dump_stack() implementation.
dump_stack_print_info() is moved to kernel/printk.c from
lib/dump_stack.c. Because linkage is per objecct file,
dump_stack_print_info() living in the same lib file as generic
dump_stack() means that archs which implement custom dump_stack()
- at this point, only blackfin - can't use dump_stack_print_info()
as that will bring in the generic version of dump_stack() too. v1
The v1 patch broke build on blackfin due to this issue. The build
breakage was reported by Fengguang Wu.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> [s390 bits]
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Richard Kuo <rkuo@codeaurora.org> [hexagon bits]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch adds the base support for the ARMv7-M
architecture. It consists of the corresponding arch/arm/mm/ files and
various #ifdef's around the kernel. Exception handling is implemented by
a subsequent patch.
[ukleinek: squash in some changes originating from commit
b5717ba (Cortex-M3: Add support for the Microcontroller Prototyping System)
from the v2.6.33-arm1 patch stack, port to post 3.6, drop zImage
support, drop reorganisation of pt_regs, assert CONFIG_CPU_V7M doesn't
leak into installed headers and a few cosmetic changes]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Jonathan Austin <jonathan.austin@arm.com>
Tested-by: Jonathan Austin <jonathan.austin@arm.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Fix up all callers as they were before, with make one change: an
unsigned module taints the kernel, but doesn't turn off lockdep.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
get_user may fail to load from the provided __user address due to an
unhandled fault generated by the access.
In the case of the undefined instruction trap, this results in failure
to load the faulting instruction, in which case we should send SIGILL to
the task rather than continue with potentially uninitialised data.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Pull ARM audit/signal updates from Russell King:
"ARM audit/signal handling updates from Al and Will. This improves on
the work Viro did last merge window, and sorts out some of the issues
found with that work."
* 'audit' of git://git.linaro.org/people/rmk/linux-arm:
ARM: 7475/1: sys_trace: allow all syscall arguments to be updated via ptrace
ARM: 7474/1: get rid of TIF_SYSCALL_RESTARTSYS
ARM: 7473/1: deal with handlerless restarts without leaving the kernel
ARM: 7472/1: pull all work_pending logics into C function
ARM: 7471/1: Revert "7442/1: Revert "remove unused restart trampoline""
ARM: 7470/1: Revert "7443/1: Revert "new way of handling ERESTART_RESTARTBLOCK""
Pull ARM fixes from Russell King:
"This fixes various issues found during July"
* 'fixes' of git://git.linaro.org/people/rmk/linux-arm:
ARM: 7479/1: mm: avoid NULL dereference when flushing gate_vma with VIVT caches
ARM: Fix undefined instruction exception handling
ARM: 7480/1: only call smp_send_stop() on SMP
ARM: 7478/1: errata: extend workaround for erratum #720789
ARM: 7477/1: vfp: Always save VFP state in vfp_pm_suspend on UP
ARM: 7476/1: vfp: only clear vfp state for current cpu in vfp_pm_suspend
ARM: 7468/1: ftrace: Trace function entry before updating index
ARM: 7467/1: mutex: use generic xchg-based implementation for ARMv6+
ARM: 7466/1: disable interrupt before spinning endlessly
ARM: 7465/1: Handle >4GB memory sizes in device tree and mem=size@start option
While trying to get a v3.5 kernel booted on the cubox, I noticed that
VFP does not work correctly with VFP bounce handling. This is because
of the confusion over 16-bit vs 32-bit instructions, and where PC is
supposed to point to.
The rule is that FP handlers are entered with regs->ARM_pc pointing at
the _next_ instruction to be executed. However, if the exception is
not handled, regs->ARM_pc points at the faulting instruction.
This is easy for ARM mode, because we know that the next instruction and
previous instructions are separated by four bytes. This is not true of
Thumb2 though.
Since all FP instructions are 32-bit in Thumb2, it makes things easy.
We just need to select the appropriate adjustment. Do this by moving
the adjustment out of do_undefinstr() into the assembly code, as only
the assembly code knows whether it's dealing with a 32-bit or 16-bit
instruction.
Cc: <stable@vger.kernel.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This reverts commit 3b0c062267.
We no longer require the restart trampoline for syscall restarting.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Robustify ARM's die() handling with improvements from x86:
- Fix for a deadlock (before panic in the case of panic_on_oops) if we
oops under a spinlock which is also used from interrupt handler,
since the old code was unconditionally enabling interrupts.
- Usage of arch spinlock so lockdep etc doesn't get involved while
we're trying to dump out oopses.
- Deadlock prevention in the unlikely event that die() recurses.
The changes all touch the same few lines of code, so they're done
together in one patch.
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This reverts commit fa18484d09.
We need the restart trampoline back so that we can revert a related
problematic patch 6b5c8045ec ("arm: new
way of handling ERESTART_RESTARTBLOCK").
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The cacheflush syscall can fail for two reasons:
(1) The arguments are invalid (nonsensical address range or no VMA)
(2) The region generates a translation fault on a VIPT or PIPT cache
This patch allows do_cache_op to return an error code to userspace in
the case of the above. The various coherent_user_range implementations
are modified to return 0 in the case of VIVT caches or -EFAULT in the
case of an abort on v6/v7 cores.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
We can't be holding the mmap_sem while calling flush_cache_user_range
because the flush can fault. If we fault on a user address, the
page fault handler will try to take mmap_sem again. Since both places
acquire the read lock, most of the time it succeeds. However, if another
thread tries to acquire the write lock on the mmap_sem (e.g. mmap) in
between the call to flush_cache_user_range and the fault, the down_read
in do_page_fault will deadlock.
[will: removed drop of vma parameter as already queued by rmk (7365/1)]
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Dima Zavin <dima@android.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
vma isn't used and flush_cache_user_range isn't a standard macro that
is used on several archs with the same prototype. In fact only unicore32
has a macro with the same name (with an identical implementation and no
in-tree users).
This is a part of a patch proposed by Dima Zavin (with Message-id:
1272439931-12795-1-git-send-email-dima@android.com) that didn't get
accepted.
Cc: Dima Zavin <dima@android.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Pull more ARM updates from Russell King.
This got a fair number of conflicts with the <asm/system.h> split, but
also with some other sparse-irq and header file include cleanups. They
all looked pretty trivial, though.
* 'for-linus' of git://git.linaro.org/people/rmk/linux-arm: (59 commits)
ARM: fix Kconfig warning for HAVE_BPF_JIT
ARM: 7361/1: provide XIP_VIRT_ADDR for no-MMU builds
ARM: 7349/1: integrator: convert to sparse irqs
ARM: 7259/3: net: JIT compiler for packet filters
ARM: 7334/1: add jump label support
ARM: 7333/2: jump label: detect %c support for ARM
ARM: 7338/1: add support for early console output via semihosting
ARM: use set_current_blocked() and block_sigmask()
ARM: exec: remove redundant set_fs(USER_DS)
ARM: 7332/1: extract out code patch function from kprobes
ARM: 7331/1: extract out insn generation code from ftrace
ARM: 7330/1: ftrace: use canonical Thumb-2 wide instruction format
ARM: 7351/1: ftrace: remove useless memory checks
ARM: 7316/1: kexec: EOI active and mask all interrupts in kexec crash path
ARM: Versatile Express: add NO_IOPORT
ARM: get rid of asm/irq.h in asm/prom.h
ARM: 7319/1: Print debug info for SIGBUS in user faults
ARM: 7318/1: gic: refactor irq_start assignment
ARM: 7317/1: irq: avoid NULL check in for_each_irq_desc loop
ARM: 7315/1: perf: add support for the Cortex-A7 PMU
...
Disintegrate asm/system.h for ARM.
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Russell King <linux@arm.linux.org.uk>
cc: linux-arm-kernel@lists.infradead.org
Add the compiled ISA to oops dumps, along side the preempt/smp
configuration. This allows us to see immediately whether the kernel
was compiled for Thumb-2 or not.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The ARM kernel uses undefined instructions to implement
BUG/BUG_ON(). This leads to problems where people don't read one
line above the Oops message and see the "kernel BUG at ..."
message and so they wrongly assume the kernel has hit an
undefined instruction.
Instead of printing:
Internal error: Oops - undefined instruction: 0 [#1] PREEMPT SMP
print
Internal error: Oops - BUG: 0 [#1] PREEMPT SMP
This should prevent people from thinking the BUG_ON was an
undefined instruction when it was actually intentional.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Simon Glass <sjg@chromium.org>
Tested-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Initialize the contents of the vectors page immediately after we
allocate the page, but before we map it. This avoids any possible
aliases with other mappings which may need to be flushed after the
page has been mapped irrespective of the cache type.
We follow this later with a flush_cache_all() after all static memory
mappings have been initialized, which ensures that this is safe from
any cache effects.
Tested-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits)
rtmutex: Add missing rcu_read_unlock() in debug_rt_mutex_print_deadlock()
lockdep: Comment all warnings
lib: atomic64: Change the type of local lock to raw_spinlock_t
locking, lib/atomic64: Annotate atomic64_lock::lock as raw
locking, x86, iommu: Annotate qi->q_lock as raw
locking, x86, iommu: Annotate irq_2_ir_lock as raw
locking, x86, iommu: Annotate iommu->register_lock as raw
locking, dma, ipu: Annotate bank_lock as raw
locking, ARM: Annotate low level hw locks as raw
locking, drivers/dca: Annotate dca_lock as raw
locking, powerpc: Annotate uic->lock as raw
locking, x86: mce: Annotate cmci_discover_lock as raw
locking, ACPI: Annotate c3_lock as raw
locking, oprofile: Annotate oprofilefs lock as raw
locking, video: Annotate vga console lock as raw
locking, latencytop: Annotate latency_lock as raw
locking, timer_stats: Annotate table_lock as raw
locking, rwsem: Annotate inner lock as raw
locking, semaphores: Annotate inner lock as raw
locking, sched: Annotate thread_group_cputimer as raw
...
Fix up conflicts in kernel/posix-cpu-timers.c manually: making
cputimer->cputime a raw lock conflicted with the ABBA fix in commit
bcd5cff721 ("cputimer: Cure lock inversion").
ARM uses its own BUG() handler which makes its output slightly different
from other archtectures.
One of the problems is that the ARM implementation doesn't report the function
with the BUG() in it, but always reports the PC being in __bug(). The generic
implementation doesn't have this problem.
Currently we get something like:
kernel BUG at fs/proc/breakme.c:35!
Unable to handle kernel NULL pointer dereference at virtual address 00000000
...
PC is at __bug+0x20/0x2c
With this patch it displays:
kernel BUG at fs/proc/breakme.c:35!
Internal error: Oops - undefined instruction: 0 [#1] PREEMPT SMP
...
PC is at write_breakme+0xd0/0x1b4
This implementation uses an undefined instruction to implement BUG, and sets up
a bug table containing the relevant information. Many versions of gcc do not
support %c properly for ARM (inserting a # when they shouldn't) so we work
around this using distasteful macro magic.
v1: Initial version to replace existing ARM BUG() implementation with something
more similar to other architectures.
v2: Add Thumb support, remove backtrace whitespace output changes. Change to
use macros instead of requiring the asm %d flag to work (thanks to
Dave Martin <dave.martin@linaro.org>)
v3: Remove old BUG() implementation in favor of this one.
Remove the Backtrace: message (will submit this separately).
Use ARM_EXIT_KEEP() so that some architectures can dump exit text at link time
thanks to Stephen Boyd <sboyd@codeaurora.org> (although since we always
define GENERIC_BUG this might be academic.)
Rebase to linux-2.6.git master.
v4: Allow BUGS in modules (these were not reported correctly in v3)
(thanks to Stephen Boyd <sboyd@codeaurora.org> for suggesting that.)
Remove __bug() as this is no longer needed.
v5: Add %progbits as the section flags.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
Tested-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The definition of __exception_irq_entry for
CONFIG_FUNCTION_GRAPH_TRACER=y needs linux/ftrace.h, but this creates a
circular dependency with it's current home in asm/system.h. Create
asm/exception.h and update all current users.
v4: - rebase to rmk/for-next
v3: - remove redundant includes of linux/ftrace.h
v2: - document the usage restricitions of __exception*
Cc: Zoltan Devai <zdevai@gmail.com>
Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Annotate the low level hardware locks which must not be preempted.
In mainline this change documents the low level nature of
the lock - otherwise there's no functional difference. Lockdep
and Sparse checking will work as usual.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>
Signed-off-by: Arun Sharma <asharma@fb.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch allows undef_hook's to be specified for 32-bit Thumb
instructions and also to be used for thumb kernel-side code.
32-bit Thumb instructions are specified in the form:
((first_half << 16 ) | second_half)
which matches the layout used by the ARM ARM.
ptrace was handling 32-bit Thumb instructions by hooking the first
halfword and manually checking the second half. This method would be
broken by this patch so it is migrated to make use of the new Thumb-2
support.
Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Dump out the following 16-bit instruction to the faulting instruction
in the Code: line. This allows Thumb-2 instructions to be properly
encoded.
Tested-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
If the page to cmpxchg is user mode read only (not write),
we should simulate a data abort first.
Signed-off-by: Po-Yu Chuang <ratbert@faraday-tech.com>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
On some arches (x86, sh, arm, unicore, powerpc) the oops message would
print out the last sysfs file accessed.
This was very useful in finding a number of sysfs and driver core bugs
in the 2.5 and early 2.6 development days, but it has been a number of
years since this file has actually helped in debugging anything that
couldn't also be trivially determined from the stack traceback.
So it's time to delete the line. This is good as we need all the space
we can get for oops messages at times on consoles.
Acked-by: Phil Carmody <ext-phil.2.carmody@nokia.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
There are optional bits that may complement a personality ID. It is
therefore wrong to simply test against the absolute current->personality
value to determine the effective personality. The PER_LINUX_32BIT is
itself just PER_LINUX with one of those optional bits set.
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
PTRACE_SINGLESTEP is a ptrace request designed to offer single-stepping
support to userspace when the underlying architecture has hardware
support for this operation.
On ARM, we set arch_has_single_step() to 1 and attempt to emulate hardware
single-stepping by disassembling the current instruction to determine the
next pc and placing a software breakpoint on that location.
Unfortunately this has the following problems:
1.) Only a subset of ARMv7 instructions are supported
2.) Thumb-2 is unsupported
3.) The code is not SMP safe
We could try to fix this code, but it turns out that because of the above
issues it is rarely used in practice. GDB, for example, uses PTRACE_POKETEXT
and PTRACE_PEEKTEXT to manage breakpoints itself and does not require any
kernel assistance.
This patch removes the single-step emulation code from ptrace meaning that
the PTRACE_SINGLESTEP request will return -EIO on ARM. Portable code must
check the return value from a ptrace call and handle the failure gracefully.
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
arch/arm/kernel/return_address.c:37:6: warning: symbol 'return_address' was not declared. Should it be static?
arch/arm/kernel/setup.c:76:14: warning: symbol 'processor_id' was not declared. Should it be static?
arch/arm/kernel/traps.c:259:1: warning: symbol 'die_lock' was not declared. Should it be static?
arch/arm/vfp/vfpmodule.c:156:6: warning: symbol 'vfp_raise_sigfpe' was not declared. Should it be static?
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
For the Kernel to support 2 level and 3 level page tables, physical
addresses (and also page table entries) need to be 32 or 64-bits depending
upon the configuration.
This patch uses the %08llx conversion specifier for physical addresses
and page table entries, ensuring that they are cast to (long long) so
that common code can be used regardless of the datatype widths.
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Rather than passing the pte value to __pte_error, pass the raw pte_t
cookie instead. Do the same for pmd and pgd functions.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch removes the domain switching functionality via the set_fs and
__switch_to functions on cores that have a TLS register.
Currently, the ioremap and vmalloc areas share the same level 1 page
tables and therefore have the same domain (DOMAIN_KERNEL). When the
kernel domain is modified from Client to Manager (via the __set_fs or in
the __switch_to function), the XN (eXecute Never) bit is overridden and
newer CPUs can speculatively prefetch the ioremap'ed memory.
Linux performs the kernel domain switching to allow user-specific
functions (copy_to/from_user, get/put_user etc.) to access kernel
memory. In order for these functions to work with the kernel domain set
to Client, the patch modifies the LDRT/STRT and related instructions to
the LDR/STR ones.
The user pages access rights are also modified for kernel read-only
access rather than read/write so that the copy-on-write mechanism still
works. CPU_USE_DOMAINS gets disabled only if the hardware has a TLS register
(CPU_32v6K is defined) since writing the TLS value to the high vectors page
isn't possible.
The user addresses passed to the kernel are checked by the access_ok()
function so that they do not point to the kernel space.
Tested-by: Anton Vorontsov <cbouatmailru@gmail.com>
Cc: Tony Lindgren <tony@atomide.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The TLS register is only available on ARM1136 r1p0 and later.
Set HWCAP_TLS flags if hardware TLS is available and test for
it if CONFIG_CPU_32v6K is not set for V6.
Note that we set the TLS instruction in __kuser_get_tls
dynamically as suggested by Jamie Lokier <jamie@shareable.org>.
Also the __switch_to code is optimized out in most cases as
suggested by Nicolas Pitre <nico@fluxnic.net>.
Reviewed-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Kernel debuggers want to be informed of die() events, so that they
can take some action to allow the problem to be inspected. Provide
the hook in a similar manner to x86.
Note that we currently don't implement the individual trap hooks.
Acked-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Use a definition for the cmpxchg SWI instead of hard-coding the number.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Nicolas Pitre <nico@fluxnic.net>
The signal restarting code was placed on the user stack when OABI
compatibility is enabled. Unfortunately, with an EABI NX executable,
this results in an attempt to run code from the non-executable stack,
which segfaults the application.
Fix this by placing the code in the vectors page, along side the
signal return code, and directing the application to that code.
Reported-by: saeed bishara <saeed.bishara@gmail.com>
Tested-by: saeed bishara <saeed.bishara@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Make die() better match x86:
- add printing of the last accessed sysfs file
- ensure console_verbose() is called under the lock
- ensure we panic outside of oops_exit()
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
dump_mem and dump_backtrace were both using multiple printk statements
to print each line. With DEBUG_LL enabled, this causes OOPS to become
very difficult to read. Solve this by only using one printk per line.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
do_cache_op() uses find_vma() to validate its arguments without holding
any locking. This means that the VMA could vanish beneath us. Fix
this by taking a read lock on mmap_sem.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch adds the main functionality for parsing the stack unwinding
information generated by the ARM EABI toolchains. The unwinding
information consists of an index with a pair of words per function and a
table with unwinding instructions. For more information, see "Exception
Handling ABI for the ARM Architecture" at:
http://infocenter.arm.com/help/topic/com.arm.doc.subset.swdev.abi/index.html
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch moves code around in the arch/arm/kernel/traps.c file for
easier integration of the stack unwinding support.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
