Re: [x86] BUG: unable to handle kernel paging request at 00740060

[Jakub Jelinek]

On Wed, Oct 09, 2013 at 09:02:31PM +0200, Peter Zijlstra wrote:
> On Wed, Oct 09, 2013 at 08:16:13PM +0200, Jakub Jelinek wrote:
> > Confirmed as gcc bug, filed http://gcc.gnu.org/PR58670
> > Seems all of 4.[6-9] miscompile it.  Will have a look tomorrow
> > unless somebody beats me to it.  But historically, the case where
> > asm goto labels jump to fallthru basic block had numerous problems in the
> > past.
> 
> That bug lists the component as middle end; this suggests x86_64 would
> be vulnerable too, can you confirm? So far we've only observed the wrong
> code on i386 targets, x86_64 targets appeared correct.

Any target, the testcase in the bugzilla aborts on x86_64 with -O2, and
even say on ppc64 (sure, one would have to rewrite the asm to have it fail
at runtime).

	Jakub
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