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Thu, 26 Mar 2026 21:35:14 -0700 (PDT) Date: Fri, 27 Mar 2026 00:35:06 -0400 From: Gregory Price To: Pedro Falcato Cc: linux-mm@kvack.org, akpm@linux-foundation.org, hughd@google.com, david@kernel.org, ljs@kernel.org, Liam.Howlett@oracle.com, vbabka@kernel.org, rppt@kernel.org, surenb@google.com, mhocko@suse.com, baolin.wang@linux.alibaba.com, linux-kernel@vger.kernel.org, kernel-team@meta.com, stable@vger.kernel.org Subject: Re: [PATCH] mm/shmem: use invalidate_lock to fix hole-punch race Message-ID: References: <20260326162611.693539-1-gourry@gourry.net> Precedence: bulk X-Mailing-List: stable@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 Thu, Mar 26, 2026 at 07:16:05PM +0000, Pedro Falcato wrote: > On Thu, Mar 26, 2026 at 01:37:17PM -0500, Gregory Price wrote: > > _If_ there is indeed breakage here regarding tree rotations, I would suggest: > > diff --git a/mm/mmap.c b/mm/mmap.c > index 5754d1c36462..7b4e39063d67 100644 fwiw this does not resolve the BUG() i'm observing. I'm still trying to find a good reproducer that doesn't require launching ~100s of VMs and ballooning them, but the condition here seems extremely narrow. ~Gregory