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csky: Fixup CONFIG_DEBUG_RSEQ

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Put the rseq_syscall check point at the prologue of the syscall
will break the a0 ... a7. This will casue system call bug when
DEBUG_RSEQ is enabled.

So move it to the epilogue of syscall, but before syscall_trace.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
This commit is contained in:
Guo Ren 2020-05-26 06:34:50 +00:00
parent 20f69538b9
commit f36e0aab6f
1 changed files with 10 additions and 5 deletions
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15
arch/csky/kernel/entry.S
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@ -128,15 +128,11 @@ tlbop_end 1
ENTRY(csky_systemcall)
SAVE_ALL TRAP0_SIZE
zero_fp
#ifdef CONFIG_RSEQ_DEBUG
mov a0, sp
jbsr rseq_syscall
#endif
psrset ee, ie
lrw r9, __NR_syscalls
cmphs syscallid, r9 /* Check nr of syscall */
bt ret_from_exception
bt 1f
lrw r9, sys_call_table
ixw r9, syscallid
@ -162,6 +158,11 @@ ENTRY(csky_systemcall)
jsr syscallid
#endif
stw a0, (sp, LSAVE_A0) /* Save return value */
1:
#ifdef CONFIG_DEBUG_RSEQ
mov a0, sp
jbsr rseq_syscall
#endif
jmpi ret_from_exception
csky_syscall_trace:
@ -187,6 +188,10 @@ csky_syscall_trace:
#endif
stw a0, (sp, LSAVE_A0) /* Save return value */
#ifdef CONFIG_DEBUG_RSEQ
mov a0, sp
jbsr rseq_syscall
#endif
mov a0, sp /* right now, sp --> pt_regs */
jbsr syscall_trace_exit
br ret_from_exception