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| author | Markos Chandras <markos.chandras@imgtec.com> | 2014-09-16 18:55:12 +0400 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2014-11-05 23:27:46 +0300 |
| commit | bbc3708af2adfb001b3df0e9e7479d10082772c2 (patch) | |
| tree | c83a785a5da2b511bf512fcd1a97d2b90ce0b2ac /arch | |
| parent | edeb8f82dff6d09343e0ec195edae6ed19d6423e (diff) | |
| download | linux-bbc3708af2adfb001b3df0e9e7479d10082772c2.tar.xz | |
MIPS: mcount: Adjust stack pointer for static trace in MIPS32
commit 8a574cfa2652545eb95595d38ac2a0bb501af0ae upstream.
Every mcount() call in the MIPS 32-bit kernel is done as follows:
[...]
move at, ra
jal _mcount
addiu sp, sp, -8
[...]
but upon returning from the mcount() function, the stack pointer
is not adjusted properly. This is explained in details in 58b69401c797
(MIPS: Function tracer: Fix broken function tracing).
Commit ad8c396936e3 ("MIPS: Unbreak function tracer for 64-bit kernel.)
fixed the stack manipulation for 64-bit but it didn't fix it completely
for MIPS32.
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7792/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/mips/kernel/mcount.S | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/arch/mips/kernel/mcount.S b/arch/mips/kernel/mcount.S index 4c968e7efb74..55eca41c91c2 100644 --- a/arch/mips/kernel/mcount.S +++ b/arch/mips/kernel/mcount.S @@ -119,7 +119,11 @@ NESTED(_mcount, PT_SIZE, ra) nop #endif b ftrace_stub +#ifdef CONFIG_32BIT + addiu sp, sp, 8 +#else nop +#endif static_trace: MCOUNT_SAVE_REGS @@ -129,6 +133,9 @@ static_trace: move a1, AT /* arg2: parent's return address */ MCOUNT_RESTORE_REGS +#ifdef CONFIG_32BIT + addiu sp, sp, 8 +#endif .globl ftrace_stub ftrace_stub: RETURN_BACK @@ -177,6 +184,11 @@ NESTED(ftrace_graph_caller, PT_SIZE, ra) jal prepare_ftrace_return nop MCOUNT_RESTORE_REGS +#ifndef CONFIG_DYNAMIC_FTRACE +#ifdef CONFIG_32BIT + addiu sp, sp, 8 +#endif +#endif RETURN_BACK END(ftrace_graph_caller) |