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 77A9334D383 for ; Thu, 19 Mar 2026 10:27:37 +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=1773916057; cv=none; b=B02bkuNftXr40cvPYlHZS9flbm4O25T1nJMpLD5sIDkg0iM0TpVQ4c7b71RhATgaA60JP52RHTQO+3A04yXZ7/fiUd+5NV2UsKKftPuwzsUdMRM9aJFqCLKbBfCY1O631uY3zM6rsRcU+bhF5DSoQPUy684C5qkbiMUArnvy8Vc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773916057; c=relaxed/simple; bh=xZ2lKabVqASoGtP4BpjW65fcad/ukajUr/T5RjJHFf8=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=m8BrbTBNgsT9WXBBRWd5UPeign6iVQ3XKtc7v81T6RLO/h35CVY+VUMsM1k5rKx3Rx+YN0laetySwNq23wGwcE7+xrfVPtSaudZzACB1CsxDD44SpLcCHrI5cRblwRdBZMkuXUtrQNZjQqogLoafHmhqNX4UBPkllbj8ak0QMYo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=q9unHTTO; 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="q9unHTTO" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CEBB3C19424; Thu, 19 Mar 2026 10:27:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1773916057; bh=xZ2lKabVqASoGtP4BpjW65fcad/ukajUr/T5RjJHFf8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=q9unHTTOwwuOpR64TcO82yRYzZSNM/mn/heTsgU25jM7a5rBiGahBXXh7cGoas5wl jwSzSh+YwuM7KM5scaWAqQp8vTMhysJgqrcsCIJXJIP5+yPbgVgqUzclUBTBlvhBsT jZR46ekNGjB7VQm9t+R3OA3epVp1I6fz78yjdZRGot71tQ2ChVly9Qv+CpHUnz8W0o t7NP8vlRnL+7YjcWckBWl597QwN0fIneA6XYZ0rbRhfGcO6MyWNQxnlGJV5LN5KIAe hQR4+oT0CQ2Oc9S33dunguOpLYD5HPcRWD7R1fiwOAu7lTLPCAoSEkXCMEfVyhAwxv SlYZbHq4OqNcQ== Date: Thu, 19 Mar 2026 10:27:31 +0000 From: "Lorenzo Stoakes (Oracle)" To: "David Hildenbrand (Arm)" Cc: Lance Yang , syzbot , willy@infradead.org, baolin.wang@linux.alibaba.com, npache@redhat.com, linux-mm@kvack.org, baohua@kernel.org, ryan.roberts@arm.com, syzkaller-bugs@googlegroups.com, dev.jain@arm.com, ziy@nvidia.com, linux-kernel@vger.kernel.org, Liam.Howlett@oracle.com, akpm@linux-foundation.org Subject: Re: [syzbot] [mm?] kernel BUG in collapse_scan_file Message-ID: References: <69bba3c0.050a0220.227207.002b.GAE@google.com> <10e5f1d6-077d-4783-aa16-6c8b98cb9e74@lucifer.local> <8ab10631-4672-4196-b32e-7c5a01707424@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: <8ab10631-4672-4196-b32e-7c5a01707424@kernel.org> On Thu, Mar 19, 2026 at 10:21:40AM +0100, David Hildenbrand (Arm) wrote: > On 3/19/26 10:14, Lance Yang wrote: > > > > > > On 2026/3/19 17:00, David Hildenbrand (Arm) wrote: > >> On 3/19/26 09:53, Lorenzo Stoakes (Oracle) wrote: > >>> > >>> Hmm we shouldn't leave this bug in place while working for a fancier > >>> fix?? > >>> > >>> Can we get _something_ going as an upstream fix? We can improve > >>> whatever we do > >>> later right? > >>> > >>> David, thoughts? > >> > >> I recall Willy mentioning that the issue is likely a false positive. > >> > >> IIUC, that commit is not upstream? So it only triggers in linux-next. > > > > Right. That does not appear to be in upstream, I only see it in linux- > > next :) > > > >> Which means: > >> > >> 1) If it's a false positive, upstream is not effected (no XA_NODE_BUG_ON) > >> > >> 2) If it's not a false positive, upstream is effected but does not > >> trigger the XA_NODE_BUG_ON > > > > Yep. So this particular BUG_ON is not affecting upstream directly. > > > > That said, syzbot will likely keep hitting it in linux-next and > > generating noise for us until it is addressed there ... > > Right, I assume this comes through Willy's tree, so Willy should > consider removing it for the time being. > > -- > Cheers, > > David OK guys you had your fun, yes I misspoke by saying upstream, I apologise. No need to go over that repeatedly. However, linux-next ends up in upstream unless action is taken to fix patches heading there. We shouldn't, really, be just ignoring splatting kernels like that. At least that's my personal point of view on it. But anyway I really don't have the time or energy to try to track this down or push on this further. Thanks, Lorenzo