On 02/24, Will Drewry wrote:

To ensure that SIGSYS delivery occurs on return from the triggering
system call, SIGSYS is added to the SYNCHRONOUS_MASK macro.

Hmm. Can't understand... please help.

 #define SYNCHRONOUS_MASK \
 	(sigmask(SIGSEGV) | sigmask(SIGBUS) | sigmask(SIGILL) | \
-	 sigmask(SIGTRAP) | sigmask(SIGFPE))
+	 sigmask(SIGTRAP) | sigmask(SIGFPE) | sigmask(SIGSYS))

Why?

SYNCHRONOUS_MASK just tells dequeue_signal() "pick them first".
This is needed to make sure that the handler for, say SIGSEGV,
can use ucontext->ip as a faulting addr.

But seccomp adds info->si_call_addr, this looks unneeded.

Oleg.