From ba9c1d65991a8be2e160447dd06eb803cbb9ba61 Mon Sep 17 00:00:00 2001 From: Max Filippov Date: Mon, 25 Nov 2019 11:51:45 -0800 Subject: xtensa: rearrange syscall tracing system_call saves and restores syscall number across system call to make clone and execv entry and exit tracing match. This complicates things when syscall code may be changed by ptrace. Preserve syscall code in copy_thread and start_thread directly instead of doing tricks in system_call. Signed-off-by: Max Filippov --- arch/xtensa/kernel/entry.S | 6 ------ arch/xtensa/kernel/process.c | 2 ++ 2 files changed, 2 insertions(+), 6 deletions(-) (limited to 'arch/xtensa/kernel') diff --git a/arch/xtensa/kernel/entry.S b/arch/xtensa/kernel/entry.S index 2ca209e71565..59af494d9940 100644 --- a/arch/xtensa/kernel/entry.S +++ b/arch/xtensa/kernel/entry.S @@ -1895,8 +1895,6 @@ ENTRY(system_call) l32i a7, a2, PT_SYSCALL 1: - s32i a7, a1, 4 - /* syscall = sys_call_table[syscall_nr] */ movi a4, sys_call_table @@ -1930,12 +1928,8 @@ ENTRY(system_call) abi_ret(4) 1: - l32i a4, a1, 4 - l32i a3, a2, PT_SYSCALL - s32i a4, a2, PT_SYSCALL mov a6, a2 call4 do_syscall_trace_leave - s32i a3, a2, PT_SYSCALL abi_ret(4) ENDPROC(system_call) diff --git a/arch/xtensa/kernel/process.c b/arch/xtensa/kernel/process.c index db278a9e80c7..9e1c49134c07 100644 --- a/arch/xtensa/kernel/process.c +++ b/arch/xtensa/kernel/process.c @@ -264,6 +264,8 @@ int copy_thread(unsigned long clone_flags, unsigned long usp_thread_fn, ®s->areg[XCHAL_NUM_AREGS - len/4], len); } + childregs->syscall = regs->syscall; + /* The thread pointer is passed in the '4th argument' (= a5) */ if (clone_flags & CLONE_SETTLS) childregs->threadptr = childregs->areg[5]; -- cgit v1.2.3