diff options
| author | Vineet Gupta <Vineet.Gupta1@synopsys.com> | 2016-10-07 14:11:17 -0700 |
|---|---|---|
| committer | Waldemar Brodkorb <wbx@uclibc-ng.org> | 2016-10-13 21:18:32 +0200 |
| commit | 48442540e4c481474c4493192cbd9cb58c5016ad (patch) | |
| tree | 5939ca20981230da8f3950125381c5bb09113789 /libpthread | |
| parent | d388c3e67f78b414a24550a61b1bab49d7c01883 (diff) | |
ARC: nptl: cancellable wrappers were broken #2
Despite the prev fix, tst-mqueue3 was still segfaulting.
The issue was BLINK register not restored properly for return
00002690 <mq_timedsend>:
2690: sub r9,r25,0x448
2698: ld r10,[r9]
269c: cmp r10,0
26a0: beq -36
26a4: st.aw blink,[sp,-4]
26a8: st.aw r0,[sp,-4]
26ac: st.aw r1,[sp,-4]
26b0: st.aw r2,[sp,-4]
26b4: st.aw r3,[sp,-4]
26b8: st.aw r4,[sp,-4]
26bc: bl 1e28 <__librt_enable_asynccancel>
26c0: mov r9,r0
26c4: ld.ab r4,[sp,4]
26c8: ld.ab r3,[sp,4]
26cc: ld.ab r2,[sp,4]
26d0: ld.ab r1,[sp,4]
26d4: ld.ab r0,[sp,4]
26d8: ld.ab blink,[sp, 4] <---- function return BLINK
26dc: mov r8,182
26e0: trap_s 0
26e2: cmp r0,-1024
26e6: st.aw r0,[sp,-4]
26ea: mov r0,r9
26ee: bl 1e90 <__librt_disable_asynccancel> <-- BLINK clobbered
to next PC
26f2: ld.ab r0,[sp,4] <----| loops here until sp is out of bound
26fa: cmp r0,-1024 |
26fe: jls [blink] -----|
2702: b 15d8
2706: nop_s
So the fix was to retain BLINK on stack before function call, and pop it
later
- 26d8: ld.ab blink,[sp, 4]
+ 26d8: ld blink,[sp] <--- restore BLINK, but retain on stack
26dc: mov r8,182
26e0: trap_s 0
26e2: cmp r0,-1024
26e6: st.aw r0,[sp,-4]
26ea: mov r0,r9
26ee: bl 1e90 <__librt_disable_asynccancel>
26f2: ld.ab r0,[sp,4]
+ 26f6: ld.ab blink,[sp,4] <--- finally pop BLINK
26fa: cmp r0,-1024
26fe: jls [blink]
Reported-by: Eugeniy Paltsev <paltsev@synopsys.com>
Cc: Alexey Brodkin <abrodkin@synopsys.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Diffstat (limited to 'libpthread')
| -rw-r--r-- | libpthread/nptl/sysdeps/unix/sysv/linux/arc/sysdep-cancel.h | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/libpthread/nptl/sysdeps/unix/sysv/linux/arc/sysdep-cancel.h b/libpthread/nptl/sysdeps/unix/sysv/linux/arc/sysdep-cancel.h index 918f61d67..01fd844d1 100644 --- a/libpthread/nptl/sysdeps/unix/sysv/linux/arc/sysdep-cancel.h +++ b/libpthread/nptl/sysdeps/unix/sysv/linux/arc/sysdep-cancel.h @@ -38,6 +38,7 @@ mov r0, r9 /* prep mask for disable_asynccancel */ ` \ CDISABLE ` \ pop r0 /* get syscall ret value back */ ` \ + pop blink /* UNDOCARGS above left blink on stack */ ` \ cmp r0, -1024 ` \ jls [blink] ` \ b __syscall_error@plt ` \ @@ -75,7 +76,9 @@ .endm #define DOCARGS_0 push blink -#define UNDOCARGS_0 pop blink + +/* don't pop blink at this point */ +#define UNDOCARGS_0 ld blink, [sp] #define DOCARGS_1 DOCARGS_0` push r0 #define UNDOCARGS_1 pop r0` UNDOCARGS_0 |