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Date:   Wed, 16 Jun 2021 18:13:26 -0400
From:   Rafael Aquini <aquini@redhat.com>
To:     Vlastimil Babka <vbabka@suse.cz>
Cc:     Georgi Djakov <quic_c_gdjako@quicinc.com>,
        akpm@linux-foundation.org, iamjoonsoo.kim@lge.com,
        rientjes@google.com, penberg@kernel.org, cl@linux.com,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org, djakov@kernel.org
Subject: Re: [PATCH] mm/slub: Add taint after the errors are printed
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On Wed, Jun 16, 2021 at 06:34:41PM +0200, Vlastimil Babka wrote:
> On 6/16/21 6:25 PM, Georgi Djakov wrote:
> > When running the kernel with panic_on_taint, the usual slub debug error
> > messages are not being printed when object corruption happens. That's
> > because we panic in add_taint(), which is called before printing the
> > additional information. This is a bit unfortunate as the error messages
> > are actually very useful, especially before a panic. Let's fix this by
> > moving add_taint() after the errors are printed on the console.
> > 
> > Signed-off-by: Georgi Djakov <quic_c_gdjako@quicinc.com>
> 
> Makes sense.
> 
> While at it, I wonder if we should use LOCKDEP_STILL_OK instead of
> LOCKDEP_NOW_UNRELIABLE. Isn't it too pessimistic to assume that some slab's
> memory corruption hit some lock state?
>

Given there is noted corruption I don't think it's safe to assume otherwise.