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bh=irdq3O1lb1JnKN7Ou++KN+Z8sVxUlbpeb3a7cIB0eQQ=; b=1+kxJZ6JDvsHjm8I9ly5rR6gvUbx+izzd5cpwMhJmussixmJcrscZ1UThxJtwV8mRNk1n7 nennoZ5TcTT6gb/zDdBreLEDPe0Gdtx6ZSbrqEQ5lulpRHN5cEb0e8nLbm5L5jDGhFBPU0 CbrhFAqSg4KEcfczPqB9B2wYc8IqXew= X-Stat-Signature: a3pnhdh6g6fd1geitys4f5nnjowqp4zb X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: A7EA9160004 X-Rspam-User: Authentication-Results: imf08.hostedemail.com; dkim=pass header.d=google.com header.s=20210112 header.b="o/fMkgQ5"; dmarc=pass (policy=reject) header.from=google.com; spf=pass (imf08.hostedemail.com: domain of glider@google.com designates 209.85.219.176 as permitted sender) smtp.mailfrom=glider@google.com X-HE-Tag: 1667482685-80807 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, Nov 3, 2022 at 12:18 PM Peter Zijlstra wrote= : > > On Wed, Nov 02, 2022 at 12:06:11PM +0100, Alexander Potapenko wrote: > > > diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c > > index 178015a820f08..d3fdec706f1d2 100644 > > --- a/arch/x86/kernel/traps.c > > +++ b/arch/x86/kernel/traps.c > > @@ -15,6 +15,7 @@ > > #include > > #include > > #include > > +#include > > #include > > #include > > #include > > @@ -301,6 +302,12 @@ static noinstr bool handle_bug(struct pt_regs *reg= s) > > { > > bool handled =3D false; > > > > + /* > > + * Normally @regs are unpoisoned by irqentry_enter(), but handle_= bug() > > + * is a rare case that uses @regs without passing them to > > + * irqentry_enter(). > > + */ > > + kmsan_unpoison_entry_regs(regs); > > if (!is_valid_bugaddr(regs->ip)) > > return handled; > > > > Should we place this kmsan_unpoison_entry_regs() after the > instrumentation_begin() ? Agreed, let me send an update. --=20 Alexander Potapenko Software Engineer Google Germany GmbH Erika-Mann-Stra=C3=9Fe, 33 80636 M=C3=BCnchen Gesch=C3=A4ftsf=C3=BChrer: Paul Manicle, Liana Sebastian Registergericht und -nummer: Hamburg, HRB 86891 Sitz der Gesellschaft: Hamburg