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| author | Lin Yongting <linyongting@gmail.com> | 2014-11-26 14:33:49 +0100 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2014-11-27 16:00:23 +0000 |
| commit | 20cb6abfe0062693183eb2a85f7c73792e96407f (patch) | |
| tree | 8a1989fcfd9b1233d8aeed734e0e1e66147eb22b /arch/arm/lib | |
| parent | 296630c9c8c6ff5f116b417fafa6067d4c7a786e (diff) | |
| download | linux-20cb6abfe0062693183eb2a85f7c73792e96407f.tar.bz2 | |
ARM: 8223/1: Add unwinding support for __memzero function
The __memzero function never had unwinding annotations added.
Currently, when accessing invalid pointer by __memzero occurs the
backtrace shown will stop at __memzero or some completely unrelated
function. Add unwinding annotations in hopes of getting a more
useful backtrace in following cases:
1. die on accessing invalid pointer by __memzero
2. kprobe trapped at any instruction within __memzero
3. interrupted at any instruction within __memzero
Signed-off-by: Lin Yongting <linyongting@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/lib')
| -rw-r--r-- | arch/arm/lib/memzero.S | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/arch/arm/lib/memzero.S b/arch/arm/lib/memzero.S index 385ccb306fa2..0eded952e089 100644 --- a/arch/arm/lib/memzero.S +++ b/arch/arm/lib/memzero.S @@ -9,6 +9,7 @@ */ #include <linux/linkage.h> #include <asm/assembler.h> +#include <asm/unwind.h> .text .align 5 @@ -18,6 +19,7 @@ * mis-aligned by, and r1 is the number of bytes. If r1 < 4, then we * don't bother; we use byte stores instead. */ +UNWIND( .fnstart ) 1: subs r1, r1, #4 @ 1 do we have enough blt 5f @ 1 bytes to align with? cmp r3, #2 @ 1 @@ -47,6 +49,9 @@ ENTRY(__memzero) * use the LR */ str lr, [sp, #-4]! @ 1 +UNWIND( .fnend ) +UNWIND( .fnstart ) +UNWIND( .save {lr} ) mov ip, r2 @ 1 mov lr, r2 @ 1 @@ -66,6 +71,7 @@ ENTRY(__memzero) tst r1, #16 @ 1 16 bytes or more? stmneia r0!, {r2, r3, ip, lr} @ 4 ldr lr, [sp], #4 @ 1 +UNWIND( .fnend ) #else @@ -75,6 +81,9 @@ ENTRY(__memzero) */ stmfd sp!, {r4-r7, lr} +UNWIND( .fnend ) +UNWIND( .fnstart ) +UNWIND( .save {r4-r7, lr} ) mov r4, r2 mov r5, r2 mov r6, r2 @@ -105,9 +114,11 @@ ENTRY(__memzero) tst r1, #16 stmneia r0!, {r4-r7} ldmfd sp!, {r4-r7, lr} +UNWIND( .fnend ) #endif +UNWIND( .fnstart ) 4: tst r1, #8 @ 1 8 bytes or more? stmneia r0!, {r2, r3} @ 2 tst r1, #4 @ 1 4 bytes or more? @@ -122,4 +133,5 @@ ENTRY(__memzero) tst r1, #1 @ 1 a byte left over strneb r2, [r0], #1 @ 1 ret lr @ 1 +UNWIND( .fnend ) ENDPROC(__memzero) |