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=1793829705; b=2fg0NXo8WRLVUVnDaBEK9hAXtDIUPYC8SMtXkwxyMvGTTj9dTVZqjY6mIdnXGZjYR346 WnO5TFj5+ca8nRIEaADBhaS8/ie4zathyZzy9Rp5VAaM9CzM2nJZgJRDxszSGTMCmg6VA RX9w9uTM/S6Rvq5uhas4KewciXx51R/L1ojtsHoaPEGWFATKGaZSzRs5yPDkIOL29h8dy bMoNfcrgexxBnaaoqJFx6legtdz6baCORdnPSklQBMTKN7jhET/BjvMmtfkRZ6Im5UDwe iCUUIhsVjbZnkaARCLXCF1xeitM3WcfsbmXgApOAc7BtaFbn8CmDfrq3SRR48b9CWnQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793829705; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=9CyUKegCiQdsdxu/BA31qdLPo73w2RspGf4dKVPs1ow=; b=UJboG5fb2QIt/do8XiETqh+MFwHexGbJ8QHIZWy3B4yK3WTSdolzjqxJ20MdW6zrHpLm LcR8aF8/UoZZDpJ/dOwKzpz5pLtm/LHZQk2shHKZJfWpUPbcRp056hZvFQTe7roXsUDyU 5ajmbNhgJXMdU8sCf7EJAk1v5j5KpYJVxUVHJ++41GgsSSPlW0qfic5JfKCSKMY93Npiy 0WBeOsfQ4WOVrigMArH3L7kUo3ZgSeuu8Hd9azcAcgcHw/u4Y+Op4wavacU81CO9DGLho engKXz6blS1fE9Bja3sJ2cQPCqnf/t+Bv3P7A6YozBNSttqQ78bDC423YGQrR7X9TxA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=QhwLAy0r; 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 5DCF7606BA3C; Wed, 4 Nov 2026 22:01:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=QhwLAy0r Received: by smtp.kernel.org (Postfix) with ESMTPSA id A549C1F00A18; Wed, 4 Nov 2026 22:01:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793829704; bh=9CyUKegCiQdsdxu/BA31qdLPo73w2RspGf4dKVPs1ow=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=QhwLAy0rKnLNvFboS/hXnP8DNJhqZSQNNDyQ+gHA6rwUZVXG51iGbonUn5OdCM1zG 8E0wKyZ77tq/Fz2aS5NU0tb/8BMUCAux//Sr1J/Qr1NZ67tuFldU1M5cT5w56GKffV YG/Ee75TopaEVgPhJPKy1uyiO21ODtKYKUnVq3x4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Genjian Zhang , Yu Kuai , Sasha Levin Subject: [PATCH 6.18 0290/1005] md/raid5: complete discard bios while reshape is active Date: Wed, 4 Nov 2026 16:00:23 -0500 Message-ID: <20261104211052.033336350@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261104211043.516122098@linuxfoundation.org> References: <20261104211043.516122098@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Genjian Zhang [ Upstream commit 85764f475f3b3abd956bf8eaeaa643b367676cf4 ] make_discard_request() returns without completing the bio when reshape is in progress. Discard callers block in submit_bio_wait() waiting for a completion that never arrives. The caller hangs in uninterruptible sleep, and this does not resolve when reshape finishes. Complete the bio with BLK_STS_AGAIN so userspace can retry after reshape, consistent with the existing policy of not processing discard during reshape. Tested on a loop-backed RAID5 array during mdadm --grow: without this patch, blkdiscard hangs in bio_await() and remains in uninterruptible sleep after md reports "reshape done"; with this patch it returns -EAGAIN instead. Signed-off-by: Genjian Zhang Reviewed-by: Yu Kuai Link: https://patch.msgid.link/20260711161326.962336-1-zhanggenjian@126.com Signed-off-by: Yu Kuai Signed-off-by: Sasha Levin --- drivers/md/raid5.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 2817cd7d197e9..b7da2b83e1938 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -5707,8 +5707,7 @@ static void make_discard_request(struct mddev *mddev, struct bio *bi) int stripe_sectors; if (mddev->reshape_position != MaxSector) - /* Skip discard while reshape is happening */ - return; + goto complete_again; stripe_sectors = conf->chunk_sectors * (conf->raid_disks - conf->max_degraded); @@ -5786,6 +5785,11 @@ static void make_discard_request(struct mddev *mddev, struct bio *bi) } bio_endio(bi); + return; + +complete_again: + /* Skip discard while reshape is happening */ + bio_endio_status(bi, BLK_STS_AGAIN); } static bool ahead_of_reshape(struct mddev *mddev, sector_t sector, -- 2.53.0