Messages in this thread | | | Date | Mon, 29 Jul 2013 11:06:53 +0200 (CEST) | From | Jiri Kosina <> | Subject | Re: [tip:perf/core] kprobes/x86: Call out into INT3 handler directly instead of using notifier |
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On Wed, 24 Jul 2013, H. Peter Anvin wrote:
> > Commit-ID: 17f41571bb2c4a398785452ac2718a6c5d77180e > > Gitweb: http://git.kernel.org/tip/17f41571bb2c4a398785452ac2718a6c5d77180e > > Author: Jiri Kosina <jkosina@suse.cz> > > AuthorDate: Tue, 23 Jul 2013 10:09:28 +0200 > > Committer: Ingo Molnar <mingo@kernel.org> > > CommitDate: Tue, 23 Jul 2013 10:12:57 +0200 > > > > kprobes/x86: Call out into INT3 handler directly instead of using notifier > > > > In fd4363fff3d96 ("x86: Introduce int3 (breakpoint)-based > > instruction patching"), the mechanism that was introduced for > > notifying alternatives code from int3 exception handler that and > > exception occured was die_notifier. > > > > This is however problematic, as early code might be using jump > > labels even before the notifier registration has been performed, > > which will then lead to an oops due to unhandled exception. One > > of such occurences has been encountered by Fengguang: > > > > Please note that putting this patch in perf/core means x86/jumplabel is > completely nonfunctional by itself.
I'd like to point out that this is still the case ... TIA,
-- Jiri Kosina SUSE Labs
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