On Mon, Mar 16, 2015 at 05:05:53AM -0700, tip-bot for Denys Vlasenko wrote: > Commit-ID: 245214a155c711764b3853189441c9f8aeb058b3 > Gitweb: http://git.kernel.org/tip/245214a155c711764b3853189441c9f8aeb058b3 > Author: Denys Vlasenko <dvlas...@redhat.com> > AuthorDate: Tue, 10 Mar 2015 11:45:07 +0100 > Committer: Ingo Molnar <mi...@kernel.org> > CommitDate: Tue, 10 Mar 2015 13:56:11 +0100 > > x86/asm/entry/64: Remove unused thread_struct::usersp > > All manipulations of PER_CPU(old_rsp) in C code are removed: > it is not used on SYSRET return, so storing anything there is > pointless. > > This also allows us to get rid of thread_struct::usersp, > which was needed only to set PER_CPU(old_rsp) for correct > return from fork/clone. > > Tweak a few comments as well: we no longer have "partial stack frame", > ever. > > Signed-off-by: Denys Vlasenko <dvlas...@redhat.com> > Cc: Alexei Starovoitov <a...@plumgrid.com> > Cc: Borislav Petkov <b...@alien8.de> > Cc: Frederic Weisbecker <fweis...@gmail.com> > Cc: H. Peter Anvin <h...@zytor.com> > Cc: Kees Cook <keesc...@chromium.org> > Cc: Linus Torvalds <torva...@linux-foundation.org> > Cc: Oleg Nesterov <o...@redhat.com> > Cc: Steven Rostedt <rost...@goodmis.org> > Cc: Will Drewry <w...@chromium.org> > Link: > http://lkml.kernel.org/r/1425984307-2143-2-git-send-email-dvlas...@redhat.com > Signed-off-by: Ingo Molnar <mi...@kernel.org>
So this patch is causing all kinds of segfaults when booting my kvm guest here, see below. Reverting it makes the segfaults go away but from looking at the patch, I have no idea why it would even cause those segfaults. [ 5.285547] kmod[1316]: segfault at 738c08 ip 0000000000738c08 sp 00007ffdb6079c68 error 15 [ 9.537606] tput[2716]: segfault at 0 ip (null) sp 00007fffffffdbd0 error 14 in tput[400000+3000] ^^^^^^^^^^^^^^^^^ Looks like rIP has went off somewhere in the weeds. Hmmm... [ 4.593374] grep[998]: segfault at 7ffc3a9f4378 ip 00007fb8409fe1df sp 00007ffc3a9f4378 error 4 in ld-2.13.so[7fb8409e8000+20000] [ 4.593374] grep[998]: segfault at 7ffc3a9f4378 ip 00007fb8409fe1df sp 00007ffc3a9f4378 error 4 in ld-2.13.so[7fb8409e8000+20000] [ 7.160423] sed[1999]: segfault at 7ffe9998f778 ip 00007f37deef0b52 sp 00007ffe9998f778 error 4 in libc-2.13.so[7f37dee18000+182000] [ 4.593374] grep[998]: segfault at 7ffc3a9f4378 ip 00007fb8409fe1df sp 00007ffc3a9f4378 error 4 in ld-2.13.so[7fb8409e8000+20000] [ 7.160423] sed[1999]: segfault at 7ffe9998f778 ip 00007f37deef0b52 sp 00007ffe9998f778 error 4 in libc-2.13.so[7f37dee18000+182000] [ 4.593374] grep[998]: segfault at 7ffc3a9f4378 ip 00007fb8409fe1df sp 00007ffc3a9f4378 error 4 in ld-2.13.so[7fb8409e8000+20000] [ 7.160423] sed[1999]: segfault at 7ffe9998f778 ip 00007f37deef0b52 sp 00007ffe9998f778 error 4 in libc-2.13.so[7f37dee18000+182000] [ 5.607611] sed[1350]: segfault at 7ffddd4a4bf0 ip 00007ff24a11fafc sp 00007ffddd4a4bf0 error 4 in libc-2.13.so[7ff24a050000+182000] [ 9.820987] update-exim4.co[2755]: segfault at 7ffff79ab000 ip 00007ffff79ab000 sp 00007fffffffe278 error 15 [ 10.580362] tput[3060]: segfault at 7ffff6376cb0 ip 00007ffff7df3422 sp 00007ffff6376cb0 error 4 in ld-2.13.so[7ffff7ddd000+20000] [ 5.607611] sed[1350]: segfault at 7ffddd4a4bf0 ip 00007ff24a11fafc sp 00007ffddd4a4bf0 error 4 in libc-2.13.so[7ff24a050000+182000] [ 9.820987] update-exim4.co[2755]: segfault at 7ffff79ab000 ip 00007ffff79ab000 sp 00007fffffffe278 error 15 [ 10.580362] tput[3060]: segfault at 7ffff6376cb0 ip 00007ffff7df3422 sp 00007ffff6376cb0 error 4 in ld-2.13.so[7ffff7ddd000+20000] -- Regards/Gruss, Boris. ECO tip #101: Trim your mails when you reply. -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/