On Wed, Nov 26, 2014 at 05:50:27PM -0600, Peter Bergner wrote: > On Thu, 2014-11-27 at 09:38 +1100, Michael Ellerman wrote: > > On Thu, 2014-11-27 at 08:11 +1100, Anton Blanchard wrote: > > > I used some 64 bit instructions when adding the 32 bit getcpu VDSO > > > function. Fix it. > > > > Ouch. The symptom is a SIGILL I presume? > > Nope, you don't get a SIGILL when executing 64-bit instructions in > 32-bit mode, so it'll happily just execute the instruction, doing > a full 64-bit compare. I'm guessing that the upper 32-bits of both > r3 and r4 contain zeros, so we're probably just getting lucky.
You will get a SIGILL if you run on 32-bit hardware. > > Could we catch this by forcing -m32 in the CFLAGS for vdso32 ? > > As Segher mentioned, GCC passing -many down to the assembler means > -m32 won't help. It was due to Anton disabling that gcc "feature", > that this was caught. There are extremely many complex failure cases without the -many. Feel free to work on removing it, I won't :-) Segher _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
