From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 670F22D2397 for ; Sat, 18 Apr 2026 09:35:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776504944; cv=none; b=hqpQjubb35y9HyXLUq4GVULGWtew0qXuS/o+bkGvyMBrvszDCiHmN6JGBuFdYwQCddSR7+4wC/qdsZfXfAPal37dpdRjiiN8qp6kX03+0HUJBcmwHbMXlFRhz2ZT8XDBvrVXZo2b9UDHyFWupvXuBACt5ssD+4t2AtEOPy0r5Ew= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776504944; c=relaxed/simple; bh=WnNNPJsbLC3odrTyoySEhdAf76vObTQcf1eB9hxRSrM=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=GMbTLaIxKADjKrIviDps5J3dMplvij3bHLRTqsM5k0eG6JA2pquCkLhhx4rUjNUqEZtrPVtJ4iO43Fc1egQTtOo0e3UM8+/04W0lqTdXsnw7zUAwvKnY2eEeTUNshMORc/KFhtFgpbBw10f0r1rsryGoyptjgLuT/jo2XkAmvYA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Wu0KE3OJ; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Wu0KE3OJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A6419C19424; Sat, 18 Apr 2026 09:35:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1776504943; bh=WnNNPJsbLC3odrTyoySEhdAf76vObTQcf1eB9hxRSrM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Wu0KE3OJzoD85Zv4R5AGk2I5OzYsyw5GCIBbxHlhqAfNs0dyg0KdEN3sIJSw5Jtbd MoHdzjwtVup+ZJMVaw0CYqTdUIyz8qL44zsR5Bfqv53bzuRlKkAH31thrITWTkvZ9Y 9YZVCtssSVnf3cOekz7AtYTagvOOVoUZ+1aowVv0qdQ+UUM6YOcM2xtA+OoYi2QEpR TnvhF4iZUgIihc3HFC1C9XEFw/kH/Rnw8kNMfChglPecjfFwHEx1BYmCopRZ2HDjQB Xi6nGWjdb+AmJ2Yz2lIBUtIw6kcSSEhjcZxY2VNTOERfj+QeKtJzq7fmVzgU6Wjzek MU7BCugwA2wCA== Date: Sat, 18 Apr 2026 10:35:36 +0100 From: Lorenzo Stoakes To: "David Hildenbrand (Arm)" Cc: ZhengYuan Huang , akpm@linux-foundation.org, Liam.Howlett@oracle.com, vbabka@kernel.org, rppt@kernel.org, surenb@google.com, mhocko@suse.com, willy@infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, baijiaju1990@gmail.com, r33s3n6@gmail.com, zzzccc427@gmail.com Subject: Re: [PATCH] mm: prepare anon_vma before swapin rmap Message-ID: References: <20260417011606.1089985-1-gality369@gmail.com> <66f67e51-819b-4c60-9f61-170db32362a2@kernel.org> 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: On Fri, Apr 17, 2026 at 01:57:59PM +0200, David Hildenbrand (Arm) wrote: > Maybe there was a scenario where we could have lost vma->anon_vma during > a merge, resulting in a swapped page in an anon_vma. Unless there's a bug (and correct me if I'm misinterpreting), VMA merge requires vma->anon_vma to either be equal for merged adjacent VMAs, or one or the other VMA to have NULL vma->anon_vma, in which case we set vma->anon_vma in the merged VMA. Thanks, Lorenzo