Re: get syscall num in updateSyscallExit

[Andrew Cagney <cagney at redhat dot com>]

Sami, you're correct.  sigreturn, which is called when a signal handler 
exits, restores the state of a thread to what it was before an 
asynchronous signal was delivered.   Consequently, it destroys all 
registers.

Sami Wagiaalla wrote:
> Yao Qi wrote:
> > Some of test cases get syscall num in updateSyscallExit by means of
> > syscallEventInfo.number (task), but it seems that it is not right all
> > the time.
> >
> > We find that we fail to get syscall number when EXIT rt_sigreturn and
> > sigreturn on x86/x86-64/ppc64.  On x86 and x86-64, the syscall number
> > got when exit rt_sigreturn is -1.
> >
> > I am not sure it is the kernel problem or not.  Any comments on this?
> > Thanks!
> >   
> I dont think its a kernel bug. I have a feeling that we are not 
> allowed to look
> at that value on syscallExit event only syscallEnter. Please file a 
> bug and assign
> it to me :). If you have a test case that would be great
>
> Thanx,
>  Sami