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Date: Tue, 18 Feb 2025 20:03:55 -0800
From: Andrew Morton <akpm@linux-foundation.org>
To: Barry Song <21cnbao@gmail.com>
Cc: gaoxu <gaoxu2@honor.com>, "linux-mm@kvack.org" <linux-mm@kvack.org>,
 "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>, Suren
 Baghdasaryan <surenb@google.com>, Yosry Ahmed <yosry.ahmed@linux.dev>
Subject: Re: [PATCH v4] mm: Fix possible NULL pointer dereference in
 __swap_duplicate
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On Wed, 19 Feb 2025 15:28:26 +1300 Barry Song <21cnbao@gmail.com> wrote:

> > The patch seems to only provide a workaround, but there are no more
> > effective software solutions to handle the bit flips problem. This path
> > will change the issue from a system crash to a process exception, thereby
> > reducing the impact on the entire machine.
> >
> > Signed-off-by: gao xu <gaoxu2@honor.com>
> 
> Regardless of whether the above statement is 100% accurate or whether
> a bit-flip actually exists, providing this check still seems useful,
> at least for
> defensive programming.

I'm doubtful as well.

How often has this crash been observed?