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| author | Michal Simek <monstr@monstr.eu> | 2012-03-30 10:21:38 +0400 |
|---|---|---|
| committer | Michal Simek <monstr@monstr.eu> | 2012-03-30 13:37:13 +0400 |
| commit | ac64a9caa55bdfd8d24784f25c68cb7919ddabe3 (patch) | |
| tree | 9832daebc0a5c4e97388ff37aae74bf32cbfabfd /arch/microblaze/lib | |
| parent | a28d73ca3ac7fffff317e62167ef26310b951ca0 (diff) | |
| download | linux-ac64a9caa55bdfd8d24784f25c68cb7919ddabe3.tar.xz | |
microblaze: Fix stack usage in PAGE_SIZE copy_tofrom_user
If access to user space failed we need to reconstruct
stack pointer and restore all register.
This patch fixed problem introduces by:
"microblaze: Add loop unrolling for PAGE in copy_tofrom_user"
(sha1: ebe211254bfa6295f4ab0b33c7c881bdfabbab60)
Signed-off-by: Michal Simek <monstr@monstr.eu>
Diffstat (limited to 'arch/microblaze/lib')
| -rw-r--r-- | arch/microblaze/lib/uaccess_old.S | 98 |
1 files changed, 62 insertions, 36 deletions
diff --git a/arch/microblaze/lib/uaccess_old.S b/arch/microblaze/lib/uaccess_old.S index f037266cdaf3..f085995ee848 100644 --- a/arch/microblaze/lib/uaccess_old.S +++ b/arch/microblaze/lib/uaccess_old.S @@ -122,22 +122,22 @@ __strnlen_user: 15: swi r24, r5, 0x0018 + offset; \ 16: swi r25, r5, 0x001C + offset; \ .section __ex_table,"a"; \ - .word 1b, 0f; \ - .word 2b, 0f; \ - .word 3b, 0f; \ - .word 4b, 0f; \ - .word 5b, 0f; \ - .word 6b, 0f; \ - .word 7b, 0f; \ - .word 8b, 0f; \ - .word 9b, 0f; \ - .word 10b, 0f; \ - .word 11b, 0f; \ - .word 12b, 0f; \ - .word 13b, 0f; \ - .word 14b, 0f; \ - .word 15b, 0f; \ - .word 16b, 0f; \ + .word 1b, 33f; \ + .word 2b, 33f; \ + .word 3b, 33f; \ + .word 4b, 33f; \ + .word 5b, 33f; \ + .word 6b, 33f; \ + .word 7b, 33f; \ + .word 8b, 33f; \ + .word 9b, 33f; \ + .word 10b, 33f; \ + .word 11b, 33f; \ + .word 12b, 33f; \ + .word 13b, 33f; \ + .word 14b, 33f; \ + .word 15b, 33f; \ + .word 16b, 33f; \ .text #define COPY_80(offset) \ @@ -190,14 +190,17 @@ w2: sw r4, r5, r3 .align 4 /* Alignment is important to keep icache happy */ page: /* Create room on stack and save registers for storign values */ - addik r1, r1, -32 - swi r19, r1, 4 - swi r20, r1, 8 - swi r21, r1, 12 - swi r22, r1, 16 - swi r23, r1, 20 - swi r24, r1, 24 - swi r25, r1, 28 + addik r1, r1, -40 + swi r5, r1, 0 + swi r6, r1, 4 + swi r7, r1, 8 + swi r19, r1, 12 + swi r20, r1, 16 + swi r21, r1, 20 + swi r22, r1, 24 + swi r23, r1, 28 + swi r24, r1, 32 + swi r25, r1, 36 loop: /* r4, r19, r20, r21, r22, r23, r24, r25 are used for storing values */ /* Loop unrolling to get performance boost */ COPY_80(0x000); @@ -205,21 +208,44 @@ loop: /* r4, r19, r20, r21, r22, r23, r24, r25 are used for storing values */ COPY_80(0x100); COPY_80(0x180); /* copy loop */ - addik r6, r6, 0x200 - addik r7, r7, -0x200 - bneid r7, loop - addik r5, r5, 0x200 + addik r6, r6, 0x200 + addik r7, r7, -0x200 + bneid r7, loop + addik r5, r5, 0x200 + /* Restore register content */ - lwi r19, r1, 4 - lwi r20, r1, 8 - lwi r21, r1, 12 - lwi r22, r1, 16 - lwi r23, r1, 20 - lwi r24, r1, 24 - lwi r25, r1, 28 - addik r1, r1, 32 + lwi r5, r1, 0 + lwi r6, r1, 4 + lwi r7, r1, 8 + lwi r19, r1, 12 + lwi r20, r1, 16 + lwi r21, r1, 20 + lwi r22, r1, 24 + lwi r23, r1, 28 + lwi r24, r1, 32 + lwi r25, r1, 36 + addik r1, r1, 40 /* return back */ + addik r3, r0, 0 + rtsd r15, 8 + nop + +/* Fault case - return temp count */ +33: addik r3, r7, 0 + /* Restore register content */ + lwi r5, r1, 0 + lwi r6, r1, 4 + lwi r7, r1, 8 + lwi r19, r1, 12 + lwi r20, r1, 16 + lwi r21, r1, 20 + lwi r22, r1, 24 + lwi r23, r1, 28 + lwi r24, r1, 32 + lwi r25, r1, 36 + addik r1, r1, 40 + /* return back */ rtsd r15, 8 nop |