From: Andrew Morton <akpm@linux-foundation.org>
To: "Uladzislau Rezki (Sony)" <urezki@gmail.com>
Cc: Mikulas Patocka <mpatocka@redhat.com>,
Alasdair Kergon <agk@redhat.com>,
Mike Snitzer <snitzer@redhat.com>, Christoph Hellwig <hch@lst.de>,
LKML <linux-kernel@vger.kernel.org>,
DMML <dm-devel@lists.linux.dev>
Subject: Re: [RESEND PATCH] dm-ebs: Mark full buffer dirty even on partial write
Date: Thu, 16 Oct 2025 12:59:51 -0700 [thread overview]
Message-ID: <20251016125951.27bb194ab31fe5c61f657a71@linux-foundation.org> (raw)
In-Reply-To: <20251014144731.164120-1-urezki@gmail.com>
On Tue, 14 Oct 2025 16:47:31 +0200 "Uladzislau Rezki (Sony)" <urezki@gmail.com> wrote:
> When performing a read-modify-write(RMW) operation, any modification
> to a buffered block must cause the entire buffer to be marked dirty.
>
> Marking only a subrange as dirty is incorrect because the underlying
> device block size(ubs) defines the minimum read/write granularity. A
> lower device can perform I/O only on regions which are fully aligned
> and sized to ubs.
>
> This change ensures that write-back operations always occur in full
> ubs-sized chunks, matching the intended emulation semantics of the
> EBS target.
It sounds like this can result in corruption under some circumstances?
It would be helpful if you could spell this out clearly, please. What
are the userspace-visible effects of this bug and how are those effects
demonstrated?
next prev parent reply other threads:[~2025-10-16 19:59 UTC|newest]
Thread overview: 33+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-10-14 14:47 Uladzislau Rezki (Sony)
2025-10-16 19:59 ` Andrew Morton [this message]
2025-10-17 15:55 ` Uladzislau Rezki
2025-11-17 10:59 Uladzislau Rezki (Sony)
2025-11-17 20:48 ` Mikulas Patocka
2025-11-18 11:39 ` Uladzislau Rezki
2025-11-18 12:00 ` Mikulas Patocka
2025-11-18 12:40 ` Uladzislau Rezki
2025-11-18 12:46 ` Christoph Hellwig
2025-11-18 14:15 ` Benjamin Marzinski
2025-11-18 17:21 ` Mikulas Patocka
2025-11-19 5:46 ` Christoph Hellwig
2025-11-19 8:43 ` Uladzislau Rezki
2025-11-19 8:53 ` Christoph Hellwig
2025-11-19 8:57 ` Uladzislau Rezki
2025-11-19 9:00 ` Christoph Hellwig
2025-11-19 9:01 ` Uladzislau Rezki
2025-11-19 9:05 ` Christoph Hellwig
2025-11-19 9:13 ` Uladzislau Rezki
2025-11-19 9:17 ` Christoph Hellwig
2025-11-19 17:26 ` Mikulas Patocka
2025-11-20 6:21 ` Christoph Hellwig
2025-11-20 12:08 ` Uladzislau Rezki
2025-11-20 12:40 ` Uladzislau Rezki
2025-11-21 7:25 ` Christoph Hellwig
2025-11-21 7:24 ` Christoph Hellwig
2025-11-21 13:21 ` Uladzislau Rezki
2025-11-21 16:48 ` Benjamin Marzinski
2025-11-24 10:43 ` Uladzislau Rezki
2025-11-24 14:30 ` Christoph Hellwig
2025-11-24 15:30 ` Uladzislau Rezki
2025-11-24 17:00 ` Christoph Hellwig
2025-11-24 18:05 ` Uladzislau Rezki
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