[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20240125173448.e866d84cda146145cbc67c93@linux-foundation.org>
Date: Thu, 25 Jan 2024 17:34:48 -0800
From: Andrew Morton <akpm@...ux-foundation.org>
To: Alexander Potapenko <glider@...gle.com>
Cc: linux-kernel@...r.kernel.org, linux-mm@...ck.org,
kasan-dev@...glegroups.com, Marco Elver <elver@...gle.com>, Dmitry Vyukov
<dvyukov@...gle.com>, Ilya Leoshkevich <iii@...ux.ibm.com>, Nicholas
Miehlbradt <nicholas@...ux.ibm.com>
Subject: Re: [PATCH v2] mm: kmsan: remove runtime checks from
kmsan_unpoison_memory()
On Wed, 24 Jan 2024 18:31:34 +0100 Alexander Potapenko <glider@...gle.com> wrote:
> Similarly to what's been done in commit ff444efbbb9be ("kmsan: allow
I make that 85716a80c16d.
> using __msan_instrument_asm_store() inside runtime"), it should be safe
> to call kmsan_unpoison_memory() from within the runtime, as it does not
> allocate memory or take locks. Remove the redundant runtime checks.
>
> This should fix false positives seen with CONFIG_DEBUG_LIST=y when
> the non-instrumented lib/stackdepot.c failed to unpoison the memory
> chunks later checked by the instrumented lib/list_debug.c
>
> Also replace the implementation of kmsan_unpoison_entry_regs() with
> a call to kmsan_unpoison_memory().
>
"false positives" sound unpleasant. Should this fix be backported into
earlier kernels? And can we identify a suitable Fixes: target?
Powered by blists - more mailing lists