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From: Uladzislau Rezki <urezki@gmail.com>
Date: Wed, 12 Jun 2024 13:27:26 +0200
To: Zhaoyang Huang <huangzhaoyang@gmail.com>, Baoquan He <bhe@redhat.com>
Cc: Uladzislau Rezki <urezki@gmail.com>,
	"zhaoyang.huang" <zhaoyang.huang@unisoc.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Christoph Hellwig <hch@infradead.org>,
	Lorenzo Stoakes <lstoakes@gmail.com>, Baoquan He <bhe@redhat.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	hailong liu <hailong.liu@oppo.com>, linux-mm@kvack.org,
	linux-kernel@vger.kernel.org, stable@vger.kernel.org,
	steve.kang@unisoc.com
Subject: Re: [Resend PATCHv4 1/1] mm: fix incorrect vbq reference in
 purge_fragmented_block
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On Wed, Jun 12, 2024 at 10:00:14AM +0800, Zhaoyang Huang wrote:
> On Wed, Jun 12, 2024 at 2:16 AM Uladzislau Rezki <urezki@gmail.com> wrote:
> >
> > >
> > > Sorry to bother you again. Are there any other comments or new patch
> > > on this which block some test cases of ANDROID that only accept ACKed
> > > one on its tree.
> > >
> > I have just returned from vacation. Give me some time to review your
> > patch. Meanwhile, do you have a reproducer? So i would like to see how
> > i can trigger an issue that is in question.
> This bug arises from an system wide android test which has been
> reported by many vendors. Keep mount/unmount an erofs partition is
> supposed to be a simple reproducer. IMO, the logic defect is obvious
> enough to be found by code review.
>
Baoquan, any objection about this v4?

Your proposal about inserting a new vmap-block based on it belongs
to, i.e. not per-this-cpu, should fix an issue. The problem is that
such way does __not__ pre-load a current CPU what is not good.

--
Uladzislau Rezki