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[173.79.60.52]) by smtp.gmail.com with ESMTPSA id 6a1803df08f44-91bcbade61csm24949136d6.26.2026.10.16.08.18.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 16 Oct 2026 08:18:41 -0700 (PDT) Date: Fri, 16 Oct 2026 11:18:39 -0400 From: Gregory Price To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, kernel-team@meta.com, akpm@linux-foundation.org, vbabka@kernel.org, surenb@google.com, mhocko@suse.com, brendan.jackman@linux.dev, hannes@cmpxchg.org, ziy@nvidia.com, mgorman@techsingularity.net, stable@vger.kernel.org Subject: Re: [PATCH] mm/page_alloc: validate zonelist slots against concurrent rebuilds Message-ID: References: <20261015210539.3243563-1-gourry@gourry.net> Precedence: bulk X-Mailing-List: linux-kernel@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: <20261015210539.3243563-1-gourry@gourry.net> On Thu, Oct 15, 2026 at 05:05:39PM -0400, Gregory Price (Meta) wrote: > Onlining the first block of a zone (e.g. via virtio-mem or a DIMM) > rebuilds every node's zonelists in place. An allocation in flight can > then be served from a zone it never asked for: a GFP_KERNEL allocation > can get a page from ZONE_MOVABLE. > Sashiko pointed out some other race conditions (related, different), i'm going to repackage this one with those fixes because they're likely to conflict and they'll all want to be backported together. ~Gregory