diff options
author | James Hogan <[email protected]> | 2017-06-29 10:12:34 +0100 |
---|---|---|
committer | Ralf Baechle <[email protected]> | 2017-07-11 14:13:06 +0200 |
commit | 4f32a39d49b25eaa66d2420f1f03d371ea4cd906 (patch) | |
tree | b820010fc55710af5db78a1dcc486806a1fa1ef0 | |
parent | 54eca7eccc5e149825f831859123b692a565bca9 (diff) |
MIPS: Negate error syscall return in trace
The sys_exit trace event takes a single return value for the system
call, which MIPS passes the value of the $v0 (result) register, however
MIPS returns positive error codes in $v0 with $a3 specifying that $v0
contains an error code. As a result erroring system calls are traced
returning positive error numbers that can't always be distinguished from
success.
Use regs_return_value() to negate the error code if $a3 is set.
Fixes: 1d7bf993e073 ("MIPS: ftrace: Add support for syscall tracepoints.")
Signed-off-by: James Hogan <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: [email protected]
Cc: <[email protected]> # 3.13+
Patchwork: https://patchwork.linux-mips.org/patch/16651/
Acked-by: Steven Rostedt (VMware) <[email protected]>
Signed-off-by: Ralf Baechle <[email protected]>
-rw-r--r-- | arch/mips/kernel/ptrace.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/mips/kernel/ptrace.c b/arch/mips/kernel/ptrace.c index ba3b1f771256..8e2ea86dc23e 100644 --- a/arch/mips/kernel/ptrace.c +++ b/arch/mips/kernel/ptrace.c @@ -913,7 +913,7 @@ asmlinkage void syscall_trace_leave(struct pt_regs *regs) audit_syscall_exit(regs); if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT))) - trace_sys_exit(regs, regs->regs[2]); + trace_sys_exit(regs, regs_return_value(regs)); if (test_thread_flag(TIF_SYSCALL_TRACE)) tracehook_report_syscall_exit(regs, 0); |