ARM: 9259/1: stacktrace: Convert stacktrace to generic ARCH_STACKWALK

Historically architectures have had duplicated code in their stack trace
implementations for filtering what gets traced. In orde

ARM: 9259/1: stacktrace: Convert stacktrace to generic ARCH_STACKWALK

Historically architectures have had duplicated code in their stack trace
implementations for filtering what gets traced. In order to avoid this
duplication some generic code has been provided using a new interface
arch_stack_walk(), enabled by selecting ARCH_STACKWALK in Kconfig, which
factors all this out into the generic stack trace code. Convert ARM to
use this common infrastructure.

When initializing the stack frame of the current task, arm64 uses
__builtin_frame_address(1) to initialize the frame pointer, skipping
arch_stack_walk(), see the commit c607ab4f916d ("arm64: stacktrace:
don't trace arch_stack_walk()"). Since __builtin_frame_address(1) does
not work on ARM, unwind_frame() is used to unwind the stack one layer
forward before calling walk_stackframe().

Signed-off-by: Li Huafei <[email protected]>
Reviewed-by: Linus Walleij <[email protected]>
Signed-off-by: Russell King (Oracle) <[email protected]>

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ARM: 9258/1: stacktrace: Make stack walk callback consistent with generic code

As with the generic arch_stack_walk() code the ARM stack walk code takes
a callback that is called per stack frame. Cur

ARM: 9258/1: stacktrace: Make stack walk callback consistent with generic code

As with the generic arch_stack_walk() code the ARM stack walk code takes
a callback that is called per stack frame. Currently the ARM code always
passes a struct stackframe to the callback and the generic code just
passes the pc, however none of the users ever reference anything in the
struct other than the pc value. The ARM code also uses a return type of
int while the generic code uses a return type of bool though in both
cases the return value is a boolean value and the sense is inverted
between the two.

In order to reduce code duplication when ARM is converted to use
arch_stack_walk() change the signature and return sense of the ARM
specific callback to match that of the generic code.

Signed-off-by: Li Huafei <[email protected]>
Reviewed-by: Mark Brown <[email protected]>
Reviewed-by: Linus Waleij <[email protected]>
Signed-off-by: Russell King (Oracle) <[email protected]>

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ARM: 9234/1: stacktrace: Avoid duplicate saving of exception PC value

Because an exception stack frame is not created in the exception entry,
save_trace() does special handling for the exception PC,

ARM: 9234/1: stacktrace: Avoid duplicate saving of exception PC value

Because an exception stack frame is not created in the exception entry,
save_trace() does special handling for the exception PC, but this is
only needed when CONFIG_FRAME_POINTER_UNWIND=y. When
CONFIG_ARM_UNWIND=y, unwind annotations have been added to the exception
entry and save_trace() will repeatedly save the exception PC:

[0x7f000090] hrtimer_hander+0x8/0x10 [hrtimer]
[0x8019ec50] __hrtimer_run_queues+0x18c/0x394
[0x8019f760] hrtimer_run_queues+0xbc/0xd0
[0x8019def0] update_process_times+0x34/0x80
[0x801ad2a4] tick_periodic+0x48/0xd0
[0x801ad3dc] tick_handle_periodic+0x1c/0x7c
[0x8010f2e0] twd_handler+0x30/0x40
[0x80177620] handle_percpu_devid_irq+0xa0/0x23c
[0x801718d0] generic_handle_domain_irq+0x24/0x34
[0x80502d28] gic_handle_irq+0x74/0x88
[0x8085817c] generic_handle_arch_irq+0x58/0x78
[0x80100ba8] __irq_svc+0x88/0xc8
[0x80108114] arch_cpu_idle+0x38/0x3c
[0x80108114] arch_cpu_idle+0x38/0x3c <==== duplicate saved exception PC
[0x80861bf8] default_idle_call+0x38/0x130
[0x8015d5cc] do_idle+0x150/0x214
[0x8015d978] cpu_startup_entry+0x18/0x1c
[0x808589c0] rest_init+0xd8/0xdc
[0x80c00a44] arch_post_acpi_subsys_init+0x0/0x8

We can move the special handling of the exception PC in save_trace() to
the unwind_frame() of the frame pointer unwinder.

Signed-off-by: Li Huafei <[email protected]>
Reviewed-by: Linus Waleij <[email protected]>
Signed-off-by: Russell King (Oracle) <[email protected]>

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ARM: 9233/1: stacktrace: Skip frame pointer boundary check for call_with_stack()

When using the frame pointer unwinder, it was found that the stack trace
output of stack_trace_save() is incomplete i

ARM: 9233/1: stacktrace: Skip frame pointer boundary check for call_with_stack()

When using the frame pointer unwinder, it was found that the stack trace
output of stack_trace_save() is incomplete if the stack contains
call_with_stack():

[0x7f00002c] dump_stack_task+0x2c/0x90 [hrtimer]
[0x7f0000a0] hrtimer_hander+0x10/0x18 [hrtimer]
[0x801a67f0] __hrtimer_run_queues+0x1b0/0x3b4
[0x801a7350] hrtimer_run_queues+0xc4/0xd8
[0x801a597c] update_process_times+0x3c/0x88
[0x801b5a98] tick_periodic+0x50/0xd8
[0x801b5bf4] tick_handle_periodic+0x24/0x84
[0x8010ffc4] twd_handler+0x38/0x48
[0x8017d220] handle_percpu_devid_irq+0xa8/0x244
[0x80176e9c] generic_handle_domain_irq+0x2c/0x3c
[0x8052e3a8] gic_handle_irq+0x7c/0x90
[0x808ab15c] generic_handle_arch_irq+0x60/0x80
[0x8051191c] call_with_stack+0x1c/0x20

For the frame pointer unwinder, unwind_frame() checks stackframe::fp by
stackframe::sp. Since call_with_stack() switches the SP from one stack
to another, stackframe::fp and stackframe: :sp will point to different
stacks, so we can no longer check stackframe::fp by stackframe::sp. Skip
checking stackframe::fp at this point to avoid this problem.

Signed-off-by: Li Huafei <[email protected]>
Reviewed-by: Linus Waleij <[email protected]>
Signed-off-by: Russell King (Oracle) <[email protected]>

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ARM: 9191/1: arm/stacktrace, kasan: Silence KASAN warnings in unwind_frame()

The following KASAN warning is detected by QEMU.

==================================================================
BUG:

ARM: 9191/1: arm/stacktrace, kasan: Silence KASAN warnings in unwind_frame()

The following KASAN warning is detected by QEMU.

==================================================================
BUG: KASAN: stack-out-of-bounds in unwind_frame+0x508/0x870
Read of size 4 at addr c36bba90 by task cat/163

CPU: 1 PID: 163 Comm: cat Not tainted 5.10.0-rc1 #40
Hardware name: ARM-Versatile Express
[<c0113fac>] (unwind_backtrace) from [<c010e71c>] (show_stack+0x10/0x14)
[<c010e71c>] (show_stack) from [<c0b805b4>] (dump_stack+0x98/0xb0)
[<c0b805b4>] (dump_stack) from [<c0b7d658>] (print_address_description.constprop.0+0x58/0x4bc)
[<c0b7d658>] (print_address_description.constprop.0) from [<c031435c>] (kasan_report+0x154/0x170)
[<c031435c>] (kasan_report) from [<c0113c44>] (unwind_frame+0x508/0x870)
[<c0113c44>] (unwind_frame) from [<c010e298>] (__save_stack_trace+0x110/0x134)
[<c010e298>] (__save_stack_trace) from [<c01ce0d8>] (stack_trace_save+0x8c/0xb4)
[<c01ce0d8>] (stack_trace_save) from [<c0313520>] (kasan_set_track+0x38/0x60)
[<c0313520>] (kasan_set_track) from [<c0314cb8>] (kasan_set_free_info+0x20/0x2c)
[<c0314cb8>] (kasan_set_free_info) from [<c0313474>] (__kasan_slab_free+0xec/0x120)
[<c0313474>] (__kasan_slab_free) from [<c0311e20>] (kmem_cache_free+0x7c/0x334)
[<c0311e20>] (kmem_cache_free) from [<c01c35dc>] (rcu_core+0x390/0xccc)
[<c01c35dc>] (rcu_core) from [<c01013a8>] (__do_softirq+0x180/0x518)
[<c01013a8>] (__do_softirq) from [<c0135214>] (irq_exit+0x9c/0xe0)
[<c0135214>] (irq_exit) from [<c01a40e4>] (__handle_domain_irq+0xb0/0x110)
[<c01a40e4>] (__handle_domain_irq) from [<c0691248>] (gic_handle_irq+0xa0/0xb8)
[<c0691248>] (gic_handle_irq) from [<c0100b0c>] (__irq_svc+0x6c/0x94)
Exception stack(0xc36bb928 to 0xc36bb970)
b920: c36bb9c0 00000000 c0126919 c0101228 c36bb9c0 b76d7730
b940: c36b8000 c36bb9a0 c3335b00 c01ce0d8 00000003 c36bba3c c36bb940 c36bb978
b960: c010e298 c011373c 60000013 ffffffff
[<c0100b0c>] (__irq_svc) from [<c011373c>] (unwind_frame+0x0/0x870)
[<c011373c>] (unwind_frame) from [<00000000>] (0x0)

The buggy address belongs to the page:
page:(ptrval) refcount:0 mapcount:0 mapping:00000000 index:0x0 pfn:0x636bb
flags: 0x0()
raw: 00000000 00000000 ef867764 00000000 00000000 00000000 ffffffff 00000000
page dumped because: kasan: bad access detected

addr c36bba90 is located in stack of task cat/163 at offset 48 in frame:
stack_trace_save+0x0/0xb4

this frame has 1 object:
[32, 48) 'trace'

Memory state around the buggy address:
c36bb980: f1 f1 f1 f1 00 04 f2 f2 00 00 f3 f3 00 00 00 00
c36bba00: 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1
>c36bba80: 00 00 f3 f3 00 00 00 00 00 00 00 00 00 00 00 00
^
c36bbb00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
c36bbb80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
==================================================================

There is a same issue on x86 and has been resolved by the commit f7d27c35ddff
("x86/mm, kasan: Silence KASAN warnings in get_wchan()").
The solution could be applied to arm architecture too.

Signed-off-by: Lin Yujun <[email protected]>
Reported-by: He Ying <[email protected]>
Signed-off-by: Russell King (Oracle) <[email protected]>

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Revert "ARM: rethook: Add rethook arm implementation"

This reverts commit 515a49173b80a4aabcbad9a4fa2a247042378ea1.

Signed-off-by: Alexei Starovoitov <[email protected]>

ARM: rethook: Add rethook arm implementation

Add rethook arm implementation. Most of the code has been copied from
kretprobes on arm.
Since the arm's ftrace implementation is a bit special, this nee

ARM: rethook: Add rethook arm implementation

Add rethook arm implementation. Most of the code has been copied from
kretprobes on arm.
Since the arm's ftrace implementation is a bit special, this needs a
special care using from fprobe.

Signed-off-by: Masami Hiramatsu <[email protected]>
Signed-off-by: Steven Rostedt (Google) <[email protected]>
Tested-by: Steven Rostedt (Google) <[email protected]>
Signed-off-by: Alexei Starovoitov <[email protected]>
Link: https://lore.kernel.org/bpf/164735289643.1084943.15184590256680485720.stgit@devnote2

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ARM: unwind: set frame.pc correctly for current-thread unwinding

When e.g. a WARN_ON() is encountered, we attempt to unwind the current
thread. To do this, we set frame.pc to unwind_backtrace, which

ARM: unwind: set frame.pc correctly for current-thread unwinding

When e.g. a WARN_ON() is encountered, we attempt to unwind the current
thread. To do this, we set frame.pc to unwind_backtrace, which means it
points at the beginning of the function. However, the rest of the state
is initialised from within the function, which means the function
prologue has already been run.

This can be confusing, and with a recent patch from Ard, can result in
the unwinder misbehaving if we want to be strict about the PC value.

If we correctly initialise the state so it is self-consistent (in other
words, set frame.pc to the location we are initialising it) then we
eliminate this confusion, and avoid possible future issues.

Reviewed-by: Ard Biesheuvel <[email protected]>
Signed-off-by: Russell King (Oracle) <[email protected]>

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ARM: Recover kretprobe modified return address in stacktrace

Since the kretprobe replaces the function return address with
the kretprobe_trampoline on the stack, arm unwinder shows it
instead of the

ARM: Recover kretprobe modified return address in stacktrace

Since the kretprobe replaces the function return address with
the kretprobe_trampoline on the stack, arm unwinder shows it
instead of the correct return address.

This finds the correct return address from the per-task
kretprobe_instances list and verify it is in between the
caller fp and callee fp.

Note that this supports both GCC and clang if CONFIG_FRAME_POINTER=y
and CONFIG_ARM_UNWIND=n. For the ARM unwinder, this is still
not working correctly.

Signed-off-by: Masami Hiramatsu <[email protected]>
Signed-off-by: Steven Rostedt (VMware) <[email protected]>

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ARM: clang: Do not rely on lr register for stacktrace

Currently the stacktrace on clang compiled arm kernel uses the 'lr'
register to find the first frame address from pt_regs. However, that
is wron

ARM: clang: Do not rely on lr register for stacktrace

Currently the stacktrace on clang compiled arm kernel uses the 'lr'
register to find the first frame address from pt_regs. However, that
is wrong after calling another function, because the 'lr' register
is used by 'bl' instruction and never be recovered.

As same as gcc arm kernel, directly use the frame pointer (r11) of
the pt_regs to find the first frame address.

Note that this fixes kretprobe stacktrace issue only with
CONFIG_UNWINDER_FRAME_POINTER=y. For the CONFIG_UNWINDER_ARM,
we need another fix.

Signed-off-by: Masami Hiramatsu <[email protected]>
Reviewed-by: Nick Desaulniers <[email protected]>
Signed-off-by: Steven Rostedt (VMware) <[email protected]>

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ARM: 8992/1: Fix unwind_frame for clang-built kernels

Since clang does not push pc and sp in function prologues, the current
implementation of unwind_frame does not work. By using the previous
frame

ARM: 8992/1: Fix unwind_frame for clang-built kernels

Since clang does not push pc and sp in function prologues, the current
implementation of unwind_frame does not work. By using the previous
frame's lr/fp instead of saved pc/sp we get valid unwinds on clang-built
kernels.

The bounds check on next frame pointer must be changed as well since
there are 8 less bytes between frames.

This fixes /proc/<pid>/stack.

Link: https://github.com/ClangBuiltLinux/linux/issues/912

Reported-by: Miles Chen <[email protected]>
Tested-by: Miles Chen <[email protected]>
Cc: [email protected]
Reviewed-by: Nick Desaulniers <[email protected]>
Signed-off-by: Nathan Huckleberry <[email protected]>
Signed-off-by: Russell King <[email protected]>

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ARM: 8948/1: Prevent OOB access in stacktrace

The stacktrace code can read beyond the stack size, when it attempts to
read pt_regs from exception frames.

This can happen on normal, non-corrupt stac

ARM: 8948/1: Prevent OOB access in stacktrace

The stacktrace code can read beyond the stack size, when it attempts to
read pt_regs from exception frames.

This can happen on normal, non-corrupt stacks. Since the unwind
information in the extable is not correct for function prologues, the
unwinding code can return data from the stack which is not actually the
caller function address, and if in_entry_text() happens to succeed on
this value, we can end up reading data from outside the task's stack
when attempting to read pt_regs, since there is no bounds check.

Example:

[<8010e729>] (unwind_backtrace) from [<8010a9c9>] (show_stack+0x11/0x14)
[<8010a9c9>] (show_stack) from [<8057d8d7>] (dump_stack+0x87/0xac)
[<8057d8d7>] (dump_stack) from [<8012271d>] (tasklet_action_common.constprop.4+0xa5/0xa8)
[<8012271d>] (tasklet_action_common.constprop.4) from [<80102333>] (__do_softirq+0x11b/0x31c)
[<80102333>] (__do_softirq) from [<80122485>] (irq_exit+0xad/0xd8)
[<80122485>] (irq_exit) from [<8015f3d7>] (__handle_domain_irq+0x47/0x84)
[<8015f3d7>] (__handle_domain_irq) from [<8036a523>] (gic_handle_irq+0x43/0x78)
[<8036a523>] (gic_handle_irq) from [<80101a49>] (__irq_svc+0x69/0xb4)
Exception stack(0xeb491f58 to 0xeb491fa0)
1f40: 7eb14794 00000000
1f60: ffffffff 008dd32c 008dd324 ffffffff 008dd314 0000002a 801011e4 eb490000
1f80: 0000002a 7eb1478c 50c5387d eb491fa8 80101001 8023d09c 40080033 ffffffff
[<80101a49>] (__irq_svc) from [<8023d09c>] (do_pipe2+0x0/0xac)
[<8023d09c>] (do_pipe2) from [<ffffffff>] (0xffffffff)
Exception stack(0xeb491fc8 to 0xeb492010)
1fc0: 008dd314 0000002a 00511ad8 008de4c8 7eb14790 7eb1478c
1fe0: 00511e34 7eb14774 004c8557 76f44098 60080030 7eb14794 00000000 00000000
2000: 00000001 00000000 ea846c00 ea847cc0

In this example, the stack limit is 0xeb492000, but 16 bytes outside the
stack have been read.

Fix it by adding bounds checks.

Signed-off-by: Vincent Whitchurch <[email protected]>
Signed-off-by: Russell King <[email protected]>

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treewide: Add SPDX license identifier for missed files

Add SPDX license identifiers to all files which:

- Have no license information of any form

- Have EXPORT_.*_SYMBOL_GPL inside which was use

treewide: Add SPDX license identifier for missed files

Add SPDX license identifiers to all files which:

- Have no license information of any form

- Have EXPORT_.*_SYMBOL_GPL inside which was used in the
initial scan/conversion to ignore the file

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

GPL-2.0-only

Signed-off-by: Thomas Gleixner <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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arm/stacktrace: Remove the pointless ULONG_MAX marker

Terminating the last trace entry with ULONG_MAX is a completely pointless
exercise and none of the consumers can rely on it because it's
inconsi

arm/stacktrace: Remove the pointless ULONG_MAX marker

Terminating the last trace entry with ULONG_MAX is a completely pointless
exercise and none of the consumers can rely on it because it's
inconsistently implemented across architectures. In fact quite some of the
callers remove the entry and adjust stack_trace.nr_entries afterwards.

Signed-off-by: Thomas Gleixner <[email protected]>
Acked-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Josh Poimboeuf <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Alexander Potapenko <[email protected]>
Cc: Russell King <[email protected]>
Cc: [email protected]
Link: https://lkml.kernel.org/r/[email protected]

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ARM: probes: avoid adding kprobes to sensitive kernel-entry/exit code

Avoid adding kprobes to any of the kernel entry/exit or startup
assembly code, or code in the identity-mapped region. This code

ARM: probes: avoid adding kprobes to sensitive kernel-entry/exit code

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 <[email protected]>
Signed-off-by: Russell King <[email protected]>

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ARM: 8691/1: Export save_stack_trace_tsk()

The kernel watchdog is a great debugging tool for finding tasks that
consume a disproportionate amount of CPU time in contiguous chunks. One
can imagine bu

ARM: 8691/1: Export save_stack_trace_tsk()

The kernel watchdog is a great debugging tool for finding tasks that
consume a disproportionate amount of CPU time in contiguous chunks. One
can imagine building a similar watchdog for arbitrary driver threads
using save_stack_trace_tsk() and print_stack_trace(). However, this is
not viable for dynamically loaded driver modules on ARM platforms
because save_stack_trace_tsk() is not exported for those architectures.
Export save_stack_trace_tsk() for the ARM architecture to align with
x86 and support various debugging use cases such as arbitrary driver
thread watchdog timers.

Signed-off-by: Dustin Brown <[email protected]>
Signed-off-by: Russell King <[email protected]>

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sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h>

We are going to split <linux/sched/debug.h> out of <linux/sched.h>, which
will have to be picked up fro

sched/headers: Prepare for new header dependencies before moving code to <linux/sched/debug.h>

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 <[email protected]>
Cc: Mike Galbraith <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Signed-off-by: Ingo Molnar <[email protected]>

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ARM: 8172/1: Use current_stack_pointer in save_stack_trace_tsk

Use the global current_stack_pointer to get the value of the stack pointer.
This change supports being able to compile the kernel with

ARM: 8172/1: Use current_stack_pointer in save_stack_trace_tsk

Use the global current_stack_pointer to get the value of the stack pointer.
This change supports being able to compile the kernel with both gcc and clang.

Signed-off-by: Behan Webster <[email protected]>
Reviewed-by: Mark Charlebois <[email protected]>
Reviewed-by: Jan-Simon Möller <[email protected]>
Acked-by: Will Deacon <[email protected]>
Acked-by: Nicolas Pitre <[email protected]>
Signed-off-by: Russell King <[email protected]>

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ARM: 8049/1: ftrace/add save_stack_trace_regs() implementation

When configure kprobe events of ftrace with "stacktrace" option enabled
in arm, there is no stacktrace was recorded after the kprobe ev

ARM: 8049/1: ftrace/add save_stack_trace_regs() implementation

When configure kprobe events of ftrace with "stacktrace" option enabled
in arm, there is no stacktrace was recorded after the kprobe event was
triggered. The root cause is no save_stack_trace_regs() function implemented.

Implement the save_stack_trace_regs() function in arm, then ftrace will
call this architecture-related function to record the stacktrace into
ring buffer.

After this fix, stacktrace can be recorded, for example:

# mount -t debugfs nodev /sys/kernel/debug
# echo "p:netrx net_rx_action" >> /sys/kernel/debug/tracing/kprobe_events
# echo 1 > /sys/kernel/debug/tracing/events/kprobes/netrx/enable
# echo 1 > /sys/kernel/debug/tracing/options/stacktrace
# echo 1 > /sys/kernel/debug/tracing/tracing_on
# ping 127.0.0.1 -c 1
# echo 0 > /sys/kernel/debug/tracing/tracing_on

# cat /sys/kernel/debug/tracing/trace
# tracer: nop
#
# entries-in-buffer/entries-written: 12/12 #P:1
#
# _-----=> irqs-off
# / _----=> need-resched
# | / _---=> hardirq/softirq
# || / _--=> preempt-depth
# ||| / delay
# TASK-PID CPU# |||| TIMESTAMP FUNCTION
# | | | |||| | |
<------ missing some entries ---------------->
ping-1200 [000] dNs1 667.603250: netrx: (net_rx_action+0x0/0x1f8)
ping-1200 [000] dNs1 667.604738: <stack trace>
=> net_rx_action
=> do_softirq
=> local_bh_enable
=> ip_finish_output
=> ip_output
=> ip_local_out
=> ip_send_skb
=> ip_push_pending_frames
=> raw_sendmsg
=> inet_sendmsg
=> sock_sendmsg
=> SyS_sendto
=> ret_fast_syscall

Signed-off-by: Lin Yongting <[email protected]>
Acked-by: Steven Rostedt <[email protected]>
Signed-off-by: Russell King <[email protected]>

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ARM: stacktrace: include exception PC value in stacktrace output

When we unwind through an exception stack, include the saved PC value
into the stack trace: this fills in an otherwise missed functio

ARM: stacktrace: include exception PC value in stacktrace output

When we unwind through an exception stack, include the saved PC value
into the stack trace: this fills in an otherwise missed functions from
the trace (as indicated below):

[<c03f4424>] fec_enet_interrupt+0xa0/0xe8
[<c0066c0c>] handle_irq_event_percpu+0x68/0x228
[<c0066e18>] handle_irq_event+0x4c/0x6c
[<c006a024>] handle_fasteoi_irq+0xac/0x198
[<c00664b0>] generic_handle_irq+0x4c/0x60
[<c000f014>] handle_IRQ+0x40/0x98
[<c0008554>] gic_handle_irq+0x30/0x64
[<c0012900>] __irq_svc+0x40/0x50
[<c0029030>] __do_softirq+0xe0/0x2fc <====
[<c0029500>] irq_exit+0xb0/0x100
[<c000f018>] handle_IRQ+0x44/0x98
[<c0008554>] gic_handle_irq+0x30/0x64
[<c0012900>] __irq_svc+0x40/0x50
[<c000f34c>] arch_cpu_idle+0x30/0x38 <====
[<c005e1e4>] cpu_startup_entry+0xac/0x214
[<c066297c>] rest_init+0x68/0x80
[<c08ccb10>] start_kernel+0x2fc/0x358

Signed-off-by: Russell King <[email protected]>

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ARM: stacktrace: avoid listing stacktrace functions in stacktrace

While debugging the FEC ethernet driver using stacktrace, it was noticed
that the stacktraces always begin as follows:

[<c00117b4>

ARM: stacktrace: avoid listing stacktrace functions in stacktrace

While debugging the FEC ethernet driver using stacktrace, it was noticed
that the stacktraces always begin as follows:

[<c00117b4>] save_stack_trace_tsk+0x0/0x98
[<c0011870>] save_stack_trace+0x24/0x28
...

This is because the stack trace code includes the stack frames for itself.
This is incorrect behaviour, and also leads to "skip" doing the wrong
thing (which is the number of stack frames to avoid recording.)

Perversely, it does the right thing when passed a non-current thread. Fix
this by ensuring that we have a known constant number of frames above the
main stack trace function, and always skip these.

Cc: <[email protected]>
Signed-off-by: Russell King <[email protected]>

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ARM: 7913/1: fix framepointer check in unwind_frame

This patch fixes corner case when (fp + 4) overflows unsigned long,
for example: fp = 0xFFFFFFFF -> fp + 4 == 3.

Cc: <[email protected]>
Sig

ARM: 7913/1: fix framepointer check in unwind_frame

This patch fixes corner case when (fp + 4) overflows unsigned long,
for example: fp = 0xFFFFFFFF -> fp + 4 == 3.

Cc: <[email protected]>
Signed-off-by: Konstantin Khlebnikov <[email protected]>
Signed-off-by: Russell King <[email protected]>

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arm: convert core files from module.h to export.h

Many of the core ARM kernel files are not modules, but just
including module.h for exporting symbols. Now these files can
use the lighter footprint

arm: convert core files from module.h to export.h

Many of the core ARM kernel files are not modules, but just
including module.h for exporting symbols. Now these files can
use the lighter footprint export.h for this role.

There are probably lots more, but ARM files of mach-* and plat-*
don't get coverage via a simple yesconfig build. They will have
to be cleaned up and tested via using their respective configs.

Signed-off-by: Paul Gortmaker <[email protected]>

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ARM: fix /proc/$PID/stack on SMP

Rabin Vincent reports:
| On SMP, this BUG() in save_stack_trace_tsk() can be easily triggered
| from user space by reading /proc/$PID/stack, where $PID is any pid bu

ARM: fix /proc/$PID/stack on SMP

Rabin Vincent reports:
| On SMP, this BUG() in save_stack_trace_tsk() can be easily triggered
| from user space by reading /proc/$PID/stack, where $PID is any pid but
| the current process:
|
| if (tsk != current) {
| #ifdef CONFIG_SMP
| /*
| * What guarantees do we have here that 'tsk'
| * is not running on another CPU?
| */
| BUG();
| #else

Fix this by replacing the BUG() with an entry to terminate the stack
trace, returning an empty trace - I'd rather not expose the dwarf
unwinder to a volatile stack of a running thread.

Reported-by: Rabin Vincent <[email protected]>
Tested-by: Rabin Vincent <[email protected]>
Signed-off-by: Russell King <[email protected]>

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ARM: 6468/1: backtrace: fix calculation of thread stack base

When unwinding stack frames we must take care not to unwind
areas of memory that lie outside of the known extent of the stack.

This patc

ARM: 6468/1: backtrace: fix calculation of thread stack base

When unwinding stack frames we must take care not to unwind
areas of memory that lie outside of the known extent of the stack.

This patch fixes an incorrect calculation of the stack base where
THREAD_SIZE is added to the stack pointer after it has already
been aligned to this value. Since the ALIGN macro performs this
addition internally, we end up overshooting the base by 8k.

Acked-by: Catalin Marinas <[email protected]>
Signed-off-by: Will Deacon <[email protected]>
Signed-off-by: Russell King <[email protected]>

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