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Fri, 6 Mar 2026 15:20:26 -0500 (EST) Date: Fri, 6 Mar 2026 20:20:21 +0000 From: Kiryl Shutsemau To: Matthew Wilcox Cc: Chris J Arges , akpm@linux-foundation.org, william.kucharski@oracle.com, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, kernel-team@cloudflare.com Subject: Re: [PATCH RFC 1/1] mm/filemap: handle large folio split race in page cache lookups Message-ID: References: <20260305183438.1062312-1-carges@cloudflare.com> <20260305183438.1062312-2-carges@cloudflare.com> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Fri, Mar 06, 2026 at 06:41:08PM +0000, Matthew Wilcox wrote: > On Fri, Mar 06, 2026 at 06:36:30PM +0000, Kiryl Shutsemau wrote: > > The proposed change doesn't fix anything, but hides the problem. > > It would be better to downgrade the VM_BUG_ON_FOLIO() to a warning + > > retry. > > The trouble is that a retry only happens to work in ... whatever scenario > this is. If there's a persistent corruption of the radix tree, a retry > might be an infinite loop which isn't terribly helpful. Whether the problem is transient can be useful. -- Kiryl Shutsemau / Kirill A. Shutemov