From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 13D02426D18; Fri, 10 Jul 2026 13:24:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783689863; cv=none; b=NjjSz8+soWba0JeadkZ5dFglcktxKwV0hTmfwVObYYSGjFMQCedw3oyIWihdevvWTg+E+OlXAnjyKhz06e+6vL0WkxNQafkzL+7bT0F0rGDRHRbqHmBc8nBbdGK9lhz1rDfgoTylEvF3id35K7ZVCV0tljVdq5JSYH/GQHK5V/E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1783689863; c=relaxed/simple; bh=1Fon9jg74hfJtQTNtNZd+Uj09wB/Cwtq9F9KzsKn9B0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=H6GPY6Kgx0JlTdB21u+8F/wmSEo8XgdqQZHc2DkUiYuUgSaX+9gx0Kb6TTVsVTcs78Gp2GpSMUfMJO4pIAiiiuoRMtLzLrWBnp2mrd06+RsApsceUp6k6Yuac7KvLlBcYJvLJ5+PTn4cJYx/4BY/BbtX1aoj+qX4Ij6DJ/rfK6A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=NVnYB7qs; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="NVnYB7qs" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 395931F000E9; Fri, 10 Jul 2026 13:24:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1783689861; bh=1Fon9jg74hfJtQTNtNZd+Uj09wB/Cwtq9F9KzsKn9B0=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=NVnYB7qshocoVxRV8CxAk3K1UiaS25s7tEAanIJNDA0I+JhoP1Fdjd3uEVUjDb36f WAkdzxMki0U8Yxx7+84NqkzZYRg/fGDafcjw9CNYFfOueZcufTkoWVGJYRlmobzoKy nYraqm8HB5NmLtu5MlKgLyM/1vNol7ynal2bQYMTCm/kXHbgnivt+hvgAzi3/9Vq4i gs3bjvFfBU+pXvomK/gXFBg4whAGb6xa+9+JrOVyavRclkvqHHZQFI9xlERNwbUcB/ mTX45vQQ37tkfW1L4CdrW2xMXK/lcfHZS8UtusMYO7awfwKSvmQ55gzJnMiMD8/LOa /T3YJLc8QfACQ== Date: Fri, 10 Jul 2026 14:24:08 +0100 From: Lorenzo Stoakes To: Andrew Morton , Suren Baghdasaryan , "Liam R. Howlett" , Vlastimil Babka , Shakeel Butt , David Hildenbrand , Mike Rapoport , Michal Hocko , Uladzislau Rezki , Toshi Kani , Catalin Marinas , Will Deacon Cc: David Carlier , Dev Jain , Ryan Roberts , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, stable@vger.kernel.org, syzbot+fd95a72470f5a44e464c@syzkaller.appspotmail.com Subject: Re: [PATCH 1/2] mm/vmalloc: acquire init_mm read lock on huge vmap promotion Message-ID: References: <20260710-series-vmap-race-fix-v1-0-5b3794c113fe@kernel.org> <20260710-series-vmap-race-fix-v1-1-5b3794c113fe@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, Jul 10, 2026 at 01:57:46PM +0100, Lorenzo Stoakes wrote: > As per Sashiko, we need to account for x86's slightly bat... interesting > ptdump of non-init_mm page tables. Well it turns out arm64 also traverses EFI ranges which is kinda the saner end of it ;) Patch incoming in any case. Will send separately as each patch stands alone and this series is fine as-is. > > The fix is to take a nested init_mm lock in ptdump_walk_pgd(), which is > safe as nothing depends on an init_mm lock prior to acquiring an arbitrary > mm's lock. > > I think this could potentially be sent as an entirely separate patch, as it > doesn't change what this protects against, nor the x86 CPA patch, both of > which stand on their own. > > Cheers, Lorenzo Cheers, Lorenzo