From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794273475; b=0m/Z2jq82K66mntsaMq125hpuZKj8VfNUXQvUTufzMoXvJXhiaP2lhOJtqDqma4ywnFg ETePHAEnVzngnMfQ2y+JAuzKcZdy9+LVQj9KzplreyBwFcTMMkncwMlNrNZhLoD8W2F6w c1B7l0j+Zl7CUPsZ9hRtebKkIrNidcJ0jyaiONtd+KXaH34/2q60Q+wVDSViqZDey/aXc +7Z3qgOVEwezwjJ+2dUPBG2B/CArYSrxs/PkWgjCa2QVpv8oF2WnPMlyTDZHH9bhEmOVX hFyCFn5zE+7Eg3OyeDX/SfZw+J53TeEmtLqYLFnJ67X+Q0vr5+UgvnTjq5t7vWH+5XQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794273475; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: MIME-Version:Content-Type:Content-Transfer-Encoding; bh=IkI4kAgbZBg2Ya8qm1x4oQHd4qgANVhRN8oRUHojMG4=; b=SJZA+U4F80DHFyCSd2DfaZCkw4CWwOybzCIpJKTeXTgkxMbGrS9P2cLLHKe076wlw/sw QM6qzGlHF/XArVMvItSSKDBBnl082wq+LHzYLZBpbfXs/tsetC3cNMoNCVsJbLin5G3pc CrNq/zqMvrAuXFGL2UrW35yOdczKVLQ+NraGAXTqQ0IDmNkVRUxpXXAZA8WVsWA+UUxn0 R1kn0FGkvR52PlFGlt6bBNJHwQt+yBnrUnoVKG/+wXLhsGcuH3SSegdB9DXEPznPM1W7u zrOmNpArqoZ/kW+tQoBzXKvgbYwOk3gu2qrfu4auPy5zDTFoUTPV7knRCy8tapDwozA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=dfpfSQyc; 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 2D1CC606A31C for ; Tue, 10 Nov 2026 01:17:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=dfpfSQyc Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2942A1F0089F; Tue, 10 Nov 2026 01:17:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794273474; bh=IkI4kAgbZBg2Ya8qm1x4oQHd4qgANVhRN8oRUHojMG4=; h=From:To:Cc:Subject:Date; b=dfpfSQycJmV43cH1xI0kawezIRXuzkKlog5XYA558rH5LauwAMzVAS5qSANEmSaMl OC1YYoKN7lCokYEv8JT45yRjowvRojqHLeyzlw0nDOL9ECDOlQ1z90JaLQdgVbzN4U BipXKJF87rySZNoEcf/cB2WD12TxWsE5zVkSTYSS6gmSGEQyG4M0DEiRiqkJ5GkfFK f3693dTSlz32lgGjotza1BltGRPsJiSmOPfA0p3Xko0bc3uBzpd/oFyMyJcS8AniXG /KUyszimw1O8UBVXatFWZTGpOGTTuFGxUIyCGMQptqYYI4CJebDZyPfO6M25xeEaBX FmZn7pkOADp/Q== From: Sasha Levin To: cong.zhang@oss.qualcomm.com, jasowangio@gmail.com, stefanha@redhat.com, axboe@kernel.dk Cc: stable@vger.kernel.org Subject: FAILED: patch "[PATCH] virtio_blk: use synchronous quiesce in virtblk_freeze_priv()" failed to apply to 6.1-stable tree Date: Mon, 9 Nov 2026 20:17:53 -0500 Message-ID: <20261109201753-failed-6.1-6c6dec7883f8@kernel.org> X-Mailer: git-send-email 2.53.0 X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The patch below does not apply to the 6.1-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y git checkout FETCH_HEAD git cherry-pick -x 6c6dec7883f8eb10b326bc9d109a4990c885d949 # git commit -s git send-email --to '' --in-reply-to '20261109201753-failed-6.1-6c6dec7883f8@kernel.org' --subject-prefix 'PATCH 6.1.y' 'HEAD^..' Thanks, Sasha ------------------ original commit in Linus's tree ------------------ >From 6c6dec7883f8eb10b326bc9d109a4990c885d949 Mon Sep 17 00:00:00 2001 From: Cong Zhang Date: Tue, 3 Nov 2026 18:32:21 +0800 Subject: [PATCH] virtio_blk: use synchronous quiesce in virtblk_freeze_priv() blk_mq_run_work_fn() can call blk_mq_sched_dispatch_requests() through blk_mq_run_dispatch_ops(). The dispatcher checks QUEUE_FLAG_QUIESCED while the flag is clear. It can then be preempted before it gets a request. At that time, it has no queue usage reference, so blk_mq_freeze_queue() does not wait for it. virtblk_freeze_priv() then calls blk_mq_quiesce_queue_nowait() and blk_mq_unfreeze_queue(). A new request can enter the queue. The old dispatcher can run again, use its old flag check, get the new request, and call virtio_queue_rq(). At the same time, virtblk_freeze_priv() can reset the device, delete the virtqueues, and free vblk->vqs. The old dispatcher can then use a deleted virtqueue or a NULL vblk->vqs, and the kernel can crash. Fix this by using blk_mq_quiesce_queue(), which waits for dispatch code that was already running. Keep the existing freeze and unfreeze order. The queue remains quiesced until virtblk_restore_priv() calls blk_mq_unquiesce_queue(). Fixes: 7678abee0867 ("virtio-blk: don't keep queue frozen during system suspend") Cc: stable@vger.kernel.org Acked-by: Jason Wang Reviewed-by: Stefan Hajnoczi Signed-off-by: Cong Zhang Link: https://lore.kernel.org/20260911-virtblk_sync_quiesce-v1-1-a883f8f31258@oss.qualcomm.com Link: https://patch.msgid.link/20261103-virtblk_sync_quiesce-v3-1-f40233f9bdd9@oss.qualcomm.com Signed-off-by: Jens Axboe --- drivers/block/virtio_blk.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c index c8bfbf8435ac7..10ba8b0b863b8 100644 --- a/drivers/block/virtio_blk.c +++ b/drivers/block/virtio_blk.c @@ -1596,7 +1596,7 @@ static int virtblk_freeze_priv(struct virtio_device *vdev) /* Ensure no requests in virtqueues before deleting vqs. */ memflags = blk_mq_freeze_queue(q); - blk_mq_quiesce_queue_nowait(q); + blk_mq_quiesce_queue(q); blk_mq_unfreeze_queue(q, memflags); /* Ensure we don't receive any more interrupts */ -- 2.53.0