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 55AD8243376; Wed, 25 Feb 2026 01:43:16 +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=1771983796; cv=none; b=EeVX77EKyNor56ApxXKpKSyCAdgyae0MW632gsOeyW/MVRjGv3v0sDV+HalRWyKEavld81g+IxEv5niVBGckLdJ5cMcQRL/lXB0tErpvWcTeIcFS4nHCmSkh3TrNHT/uV+1saOwYfpdB9SrlGBX7hLTDD06EFda/yi1JuzapA4o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771983796; c=relaxed/simple; bh=lfNPBaGSuvuWKjY+PyHfOfXScMTN2+C1O03p7BqNU7I=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=JffJzNbN95OcTJlTRlHY1XD3bmIXYTLffNpKLbsGjQaFPhc6X4Jo547NqSLgx59GWdVq6bOL5pgOEMEfHx3D44QmUiyYXKl2H5UKr7pqMBKgGJI1n9YNDopJOdtxddaIEyEdImDRbK6jfQFJLtR6LMU2jSHRARkByo/GNgvTOGY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=bf8zjNUd; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="bf8zjNUd" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 12662C116D0; Wed, 25 Feb 2026 01:43:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1771983796; bh=lfNPBaGSuvuWKjY+PyHfOfXScMTN2+C1O03p7BqNU7I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=bf8zjNUd8jYDbzYnYKFsHEpjjR4qKb+tLeDRmv3AZGZDKsLV4kr8i9mgGi23KImFx eQH5lvuZlmeu3YaV/tyj8MFSLbvbrjAyFfXr42ruhMrGWn+F+fn8gTadDXbgipzm2W jqFixWhZi8J1rCc107snFW2sCZGNZKZIkoHaxpE0= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Yu Kuai , Li Nan , Sasha Levin Subject: [PATCH 6.18 045/641] md/raid5: fix IO hang with degraded array with llbitmap Date: Tue, 24 Feb 2026 17:16:11 -0800 Message-ID: <20260225012350.120166425@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260225012348.915798704@linuxfoundation.org> References: <20260225012348.915798704@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Yu Kuai [ Upstream commit cd1635d844d26471c56c0a432abdee12fc9ad735 ] When llbitmap bit state is still unwritten, any new write should force rcw, as bitmap_ops->blocks_synced() is checked in handle_stripe_dirtying(). However, later the same check is missing in need_this_block(), causing stripe to deadloop during handling because handle_stripe() will decide to go to handle_stripe_fill(), meanwhile need_this_block() always return 0 and nothing is handled. Link: https://lore.kernel.org/linux-raid/20260123182623.3718551-2-yukuai@fnnas.com Fixes: 5ab829f1971d ("md/md-llbitmap: introduce new lockless bitmap") Signed-off-by: Yu Kuai Reviewed-by: Li Nan Signed-off-by: Sasha Levin --- drivers/md/raid5.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 1041788a54c20..3b711a1198adb 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -3751,9 +3751,14 @@ static int need_this_block(struct stripe_head *sh, struct stripe_head_state *s, struct r5dev *dev = &sh->dev[disk_idx]; struct r5dev *fdev[2] = { &sh->dev[s->failed_num[0]], &sh->dev[s->failed_num[1]] }; + struct mddev *mddev = sh->raid_conf->mddev; + bool force_rcw = false; int i; - bool force_rcw = (sh->raid_conf->rmw_level == PARITY_DISABLE_RMW); + if (sh->raid_conf->rmw_level == PARITY_DISABLE_RMW || + (mddev->bitmap_ops && mddev->bitmap_ops->blocks_synced && + !mddev->bitmap_ops->blocks_synced(mddev, sh->sector))) + force_rcw = true; if (test_bit(R5_LOCKED, &dev->flags) || test_bit(R5_UPTODATE, &dev->flags)) -- 2.51.0