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From:   Alexander Potapenko <glider@google.com>
Date:   Mon, 16 May 2022 13:49:16 +0200
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Subject: Re: [PATCH v3 27/46] kmsan: instrumentation.h: add instrumentation_begin_with_regs()
To:     Thomas Gleixner <tglx@linutronix.de>
Cc:     Alexander Viro <viro@zeniv.linux.org.uk>,
        Andrew Morton <akpm@linux-foundation.org>,
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On Wed, Apr 27, 2022 at 3:28 PM Thomas Gleixner <tglx@linutronix.de> wrote:
>
> On Tue, Apr 26 2022 at 18:42, Alexander Potapenko wrote:
> > +void kmsan_instrumentation_begin(struct pt_regs *regs)
> > +{
> > +     struct kmsan_context_state *state =3D &kmsan_get_context()->cstat=
e;
> > +
> > +     if (state)
> > +             __memset(state, 0, sizeof(struct kmsan_context_state));
>
>   sizeof(*state) please
>
> > +     if (!kmsan_enabled || !regs)
> > +             return;
>
> Why has state to be cleared when kmsan is not enabled and how do you end =
up
> with regs =3D=3D NULL here?
>
> Thanks,
>
>         tglx
>
> --
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As discussed in another thread, I'll be dropping this patch in favor
of the new kmsan_unpoison_entry_regs().

I'll also ensure I consistently use sizeof(*pointer) where applicable.

Regarding regs=3D=3DNULL, this is actually not a thing.

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Alexander Potapenko
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