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smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=dUgjHgXC; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8F4F1606A31A; Tue, 27 Oct 2026 08:57:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=dUgjHgXC Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3A7941F01825; Tue, 27 Oct 2026 08:57:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793091476; bh=+4pbRIjFXMEepoatVp5SvymIGyJoferIQRKoHK5neBI=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=dUgjHgXCJ4vLfIuFrQEgzWR4UlIov1j6lq3IiUh6JykkYZoVRU4FVQ+eqKzEWh5JP bGhTuBV6JzJbZD3EjvcLgLbt0bqoT3GIfOiZwPcqVKjryOgz8ZWvBYHCUZGyH46jvf OHaWWaQzE1JxaRR+skY0/u9B3GBcNsWDTwe71wYLsulu3nOBOfQtuA/9M9RJahs96+ NFAos8uWErreYYeOHA8j4HPZ2s6teErhWiB8tB3nga6FegO5utJqYFN57oH5LdO4zo Em+16p83yNb+piA3yiqaSL7fPNO0DXlZ2SfnI+pnTKb5X3SUIKBv8vT7hvRXNbwVEp gs0KuoCw3FFGA== Message-ID: <01d7d54d-0047-4eb6-a1d2-5b3f113f26cf@kernel.org> Date: Tue, 27 Oct 2026 09:57:48 +0100 X-Mailing-List: linux-cxl@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 0/6] mm: fix pfn walker races with memory offline To: "Gregory Price (Meta)" , linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, linux-cxl@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, linmiaohe@huawei.com, nao.horiguchi@gmail.com, ljs@kernel.org, liam@infradead.org, rppt@kernel.org, osalvador@suse.de, muchun.song@linux.dev, iamjoonsoo.kim@lge.com, anshuman.khandual@arm.com References: <20261027042204.3741307-1-gourry@gourry.net> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 10/27/26 05:21, Gregory Price (Meta) wrote: > Several pfn walkers check that a struct page is online, then use it > after memory offline has poisoned it (CONFIG_DEBUG_VM) or removal has > freed the vmemmap. Five of the races crash the kernel; the sixth leaves > an offline spinning with the device hotplug lock held. I have roughly the exact same list of AI garbage fixes here from a certain company. And I consider this all extremely low priority. So this is something to discuss throughout the next months and do it properly. -- Cheers, David