Re: [PATCH 0/5] Synchronize nd_syscalls.stp with syscalls.stp

[Josh Stone <jistone at redhat dot com>]

On 05/22/2009 03:51 PM, Josh Stone wrote:
> On 05/22/2009 08:46 AM, Przemyslaw Pawelczyk wrote:
> > Hi,
> >
> > Here are a few patches for nd_syscalls.stp to sync it with syscalls.stp.
> > [...]
> >     Unify formatting of nd_syscalls.stp.
> >     Remove return probes for exit[_group] in nd_syscalls.stp.
> >     Add missing probe points in nd_syscalls.stp.
> >     Fix nd_syscalls.stp for architectures using SYSCALL_WRAPPERS.
> >     Uncomment 'name' variable in nd_syscall.lseek probe point.
>
> As we discussed on IRC, I have committed patches 1, 2, 3, and 5.  We'll
> wait on the SYSCALL_WRAPPERS addition until bugzillas 10189 and/or 10190
> are resolved.

I committed a fix for PR10190, so now an optional probe won't print a 
registration WARNING.  However, I think we need another iteration on the 
SYSCALL_WRAPPERS patch.

> +probe nd_syscall.access = kprobe.function("SyS_access") ?,
> +                          kprobe.function("sys_access")

On a kernel without wrappers, SyS_access will fail and be silently 
ignored, and sys_access will be the only thing probed.  (good)

On a kernel with wrappers, SyS_access will be probed, and sys_access 
will fail loudly.  (not good)

Unfortunately, I think the only way around this is to mark everything 
with '?'.

Josh