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Groups > linux.kernel > #1586912
| From | Josh Poimboeuf <jpoimboe@redhat.com> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | Re: [PATCH] x86: Implement __WARN using UD0 |
| Date | 2017-02-23 15:20 +0100 |
| Message-ID | <te2pr-2oI-9@gated-at.bofh.it> (permalink) |
| References | <te1D4-1LK-9@gated-at.bofh.it> |
| Organization | linux.* mail to news gateway |
On Thu, Feb 23, 2017 at 02:28:13PM +0100, Peter Zijlstra wrote: > +/* > + * Only UD2 is defined in the Intel SDM and AMD64 docs, > + * but the interweb provided UD0 and UD1: > + * > + * https://groups.google.com/forum/#!topic/alt.os.assembly/_rS4L0fnqGE FYI, the latest Intel SDM does have UD0 and UD1. I guess AMD64 and hypervisors don't need to know about it, since if they don't, it will still trigger the same invalid opcode exception anyway? Any idea what the functional difference is between UD0 and UD2? > + * Since some emulators terminate on UD2, we cannot use it for WARN. That's too bad, which emulators are those? > + * Since various instruction decoders disagree on the length of UD1, > + * we cannot use it either. So use UD0 for WARN. It shows up as "(bad)" in objtool and gdb, though it still gets the length right: 8b9: 0f ff (bad) It would be nice if the tools knew about it... -- Josh
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[PATCH] x86: Implement __WARN using UD0 Peter Zijlstra <peterz@infradead.org> - 2017-02-23 14:30 +0100
Re: [PATCH] x86: Implement __WARN using UD0 Arjan van de Ven <arjan@linux.intel.com> - 2017-02-23 15:20 +0100
Re: [PATCH] x86: Implement __WARN using UD0 Peter Zijlstra <peterz@infradead.org> - 2017-02-23 16:00 +0100
Re: [PATCH] x86: Implement __WARN using UD0 Ingo Molnar <mingo@kernel.org> - 2017-02-24 09:00 +0100
Re: [PATCH] x86: Implement __WARN using UD0 Peter Zijlstra <peterz@infradead.org> - 2017-02-24 09:40 +0100
Re: [PATCH] x86: Implement __WARN using UD0 Ingo Molnar <mingo@kernel.org> - 2017-02-24 10:20 +0100
Re: [PATCH] x86: Implement __WARN using UD0 Borislav Petkov <bp@alien8.de> - 2017-02-24 10:50 +0100
Re: [PATCH] x86: Implement __WARN using UD0 "H. Peter Anvin" <hpa@zytor.com> - 2017-02-24 12:50 +0100
Re: [PATCH] x86: Implement __WARN using UD0 Peter Zijlstra <peterz@infradead.org> - 2017-02-24 12:50 +0100
Re: [PATCH] x86: Implement __WARN using UD0 Borislav Petkov <bp@alien8.de> - 2017-02-25 11:50 +0100
Re: [PATCH] x86: Implement __WARN using UD0 hpa@zytor.com - 2017-02-25 19:00 +0100
Re: [PATCH] x86: Implement __WARN using UD0 Borislav Petkov <bp@alien8.de> - 2017-02-25 20:40 +0100
Re: [PATCH] x86: Implement __WARN using UD0 Borislav Petkov <bp@alien8.de> - 2017-02-25 21:40 +0100
Re: [PATCH] x86: Implement __WARN using UD0 hpa@zytor.com - 2017-02-25 21:50 +0100
Re: [PATCH] x86: Implement __WARN using UD0 hpa@zytor.com - 2017-02-24 10:20 +0100
Re: [PATCH] x86: Implement __WARN using UD0 hpa@zytor.com - 2017-02-24 10:50 +0100
Re: [PATCH] x86: Implement __WARN using UD0 Peter Zijlstra <peterz@infradead.org> - 2017-02-23 15:20 +0100
Re: [PATCH] x86: Implement __WARN using UD0 Peter Zijlstra <peterz@infradead.org> - 2017-02-23 16:00 +0100
Re: [PATCH] x86: Implement __WARN using UD0 hpa@zytor.com - 2017-02-23 16:20 +0100
Re: [PATCH] x86: Implement __WARN using UD0 Peter Zijlstra <peterz@infradead.org> - 2017-02-23 16:30 +0100
Re: [PATCH] x86: Implement __WARN using UD0 hpa@zytor.com - 2017-02-23 16:40 +0100
Re: [PATCH] x86: Implement __WARN using UD0 Borislav Petkov <bp@alien8.de> - 2017-02-23 17:10 +0100
Re: [PATCH] x86: Implement __WARN using UD0 Josh Poimboeuf <jpoimboe@redhat.com> - 2017-02-23 15:20 +0100
Re: [PATCH] x86: Implement __WARN using UD0 Borislav Petkov <bp@alien8.de> - 2017-02-23 15:30 +0100
Re: [PATCH] x86: Implement __WARN using UD0 Peter Zijlstra <peterz@infradead.org> - 2017-02-23 15:40 +0100
[PATCH -v2] x86: Implement __WARN using UD0 Peter Zijlstra <peterz@infradead.org> - 2017-02-24 12:20 +0100
[RFC][PATCH] bug: Add _ONCE logic to report_bug() Peter Zijlstra <peterz@infradead.org> - 2017-02-25 10:10 +0100
Re: [RFC][PATCH] bug: Add _ONCE logic to report_bug() Ingo Molnar <mingo@kernel.org> - 2017-02-25 10:20 +0100
Re: [RFC][PATCH] bug: Add _ONCE logic to report_bug() Peter Zijlstra <peterz@infradead.org> - 2017-02-25 11:50 +0100
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