Re: [bug report] lib/vdso: Provide generic VDSO implementation

[Dan Carpenter <dan.carpenter@oracle.com>]

On Thu, Jun 27, 2019 at 12:26:06PM +0200, walter harms wrote:
> 
> 
> Am 27.06.2019 11:09, schrieb Vincenzo Frascino:
> > Hi Dan,
> > 
> > On 6/27/19 10:07 AM, Dan Carpenter wrote:
> >> On Thu, Jun 27, 2019 at 09:58:18AM +0100, Vincenzo Frascino wrote:
> >>>>    119	fallback:
> >>>>    120		return clock_gettime_fallback(clock, (struct __kernel_timespec *)res);
> >>>>                                                                                  ^^^
> >>>> On x86 this "res" always gets dereferenced.
> >>>>
> >>>>    121	}
> >>>>
> >>>
> >>> I am not sure I understand the details of this bug report. As far as I can see
> >>> "res" is never dereferenced in the vDSO library in this case, but it is passed
> >>> to the system call unchanged.
> >>>
> >>
> >> Oh yeah.  Sorry.  My bad.  False positive.  clock_gettime_fallback()
> >> doesn't necessarily dereference "res".
> >>
> > 
> > No problem, better a false positive than an ignored negative :-)
> > 
> 
> maybe it would be clever to add a comment here indicating that this
> is intended and no problem ?
> 

No.  The correct response is to fix Smatch.  I will do it.

regards,
dan carpenter