Re: [PATCH 07/14] powerpc: Add support for restartable sequences
From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Date: 2018-05-18 18:17:20
Also in:
linuxppc-dev, lkml
----- On May 17, 2018, at 7:50 PM, Boqun Feng boqun.feng@gmail.com wrote: [...]
quoted
quoted
I think you're right. So we have to introduce callsite to rseq_syscall() in syscall path, something like:diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S index 51695608c68b..a25734a96640 100644 --- a/arch/powerpc/kernel/entry_64.S +++ b/arch/powerpc/kernel/entry_64.S@@ -222,6 +222,9 @@ system_call_exit:mtmsrd r11,1 #endif /* CONFIG_PPC_BOOK3E */ + addi r3,r1,STACK_FRAME_OVERHEAD + bl rseq_syscall + ld r9,TI_FLAGS(r12) li r11,-MAX_ERRNO andi. r0,r9,(_TIF_SYSCALL_DOTRACE|_TIF_SINGLESTEP|_TIF_USER_WORK_MASK|_TIF_PERSYSCALL_MASK)
By the way, I think this is not the right spot to call rseq_syscall, because interrupts are disabled. I think we should move this hunk right after system_call_exit. Would you like to implement and test an updated patch adding those calls for ppc 32 and 64 ? Thanks, Mathieu -- Mathieu Desnoyers EfficiOS Inc. http://www.efficios.com