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 1D2F1281535; Thu, 3 Apr 2025 19:08:24 +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=1743707304; cv=none; b=S/Qt8QzcD1rUBJpv/pFojgiIbNrpyeR5bjqhcB/AMMng/KTZuP+WKLBfG94uDcvCKt70cgTgzfRRGhXTxFYROcT4fDqQIjukpAKCMuDgm+tFxeB1XmXH+bveXmF7qEl1TTYaGtnuQYx1jRQD1Chv3Qz7ahSHFoVeELTeaRHdqcE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743707304; c=relaxed/simple; bh=mnpJnS40cjWgCKmwywYGZ8atzlbrAkzFewKrRBNkayM=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=edK6cf3B1UZfZ5MwC2uQe25HqAhl0w/QptL5ibam+/G02gqdB/o/ILOCXwJUTOi1V9LMiqSpTWeVMsXqZf5lmkgbpafJKRSbCRQH0Lp4eZPirVEVpWwZoWpu0XZ5tW0RaS+nOoxYHn//CYdTkwDXqZwbi9McbtmzGRTJyaMvv/0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=SLMdZpbD; 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="SLMdZpbD" Received: by smtp.kernel.org (Postfix) with ESMTPSA id EBEFCC4CEE8; Thu, 3 Apr 2025 19:08:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1743707304; bh=mnpJnS40cjWgCKmwywYGZ8atzlbrAkzFewKrRBNkayM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SLMdZpbD2C98mNhklgDpB8VWmsaVB30TYsUPglnby/IZcOUMlifzqXpuUqYqAQnZ4 pJQDqw1KT24nq9U7j+19KJbTxq4GrqRASMrkLQAfYN4Y1aUJBrs5si3PhLYaaKvaqt vZCB1kmsxH06Vo37M7X+VoHBdcSlGevOV9nmV52lKOtb8JY/7FjECBjZIANLY6BEg5 cymlFYahFcjy3/Wo3Clw0WPNY9qe86/HKmSUbZbCMogQjySGqXG6XOB87Isw9tbKff GEf2xUOyw3bULYkeeHZjgg74b6/h86JD6NA9aEHJ+cwFxHjLufiT9D5qQzrlnyK3SR 3YOgjhYm8Nesg== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Ojaswin Mujoo , Jan Kara , Baokun Li , Theodore Ts'o , Sasha Levin , adilger.kernel@dilger.ca, linux-ext4@vger.kernel.org Subject: [PATCH AUTOSEL 6.6 17/26] ext4: protect ext4_release_dquot against freezing Date: Thu, 3 Apr 2025 15:07:36 -0400 Message-Id: <20250403190745.2677620-17-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250403190745.2677620-1-sashal@kernel.org> References: <20250403190745.2677620-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.6.85 Content-Transfer-Encoding: 8bit From: Ojaswin Mujoo [ Upstream commit 530fea29ef82e169cd7fe048c2b7baaeb85a0028 ] Protect ext4_release_dquot against freezing so that we don't try to start a transaction when FS is frozen, leading to warnings. Further, avoid taking the freeze protection if a transaction is already running so that we don't need end up in a deadlock as described in 46e294efc355 ext4: fix deadlock with fs freezing and EA inodes Suggested-by: Jan Kara Signed-off-by: Ojaswin Mujoo Reviewed-by: Baokun Li Reviewed-by: Jan Kara Link: https://patch.msgid.link/20241121123855.645335-3-ojaswin@linux.ibm.com Signed-off-by: Theodore Ts'o Signed-off-by: Sasha Levin --- fs/ext4/super.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/fs/ext4/super.c b/fs/ext4/super.c index f019ce64eba48..26d693813a80f 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -6926,12 +6926,25 @@ static int ext4_release_dquot(struct dquot *dquot) { int ret, err; handle_t *handle; + bool freeze_protected = false; + + /* + * Trying to sb_start_intwrite() in a running transaction + * can result in a deadlock. Further, running transactions + * are already protected from freezing. + */ + if (!ext4_journal_current_handle()) { + sb_start_intwrite(dquot->dq_sb); + freeze_protected = true; + } handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA, EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb)); if (IS_ERR(handle)) { /* Release dquot anyway to avoid endless cycle in dqput() */ dquot_release(dquot); + if (freeze_protected) + sb_end_intwrite(dquot->dq_sb); return PTR_ERR(handle); } ret = dquot_release(dquot); @@ -6942,6 +6955,10 @@ static int ext4_release_dquot(struct dquot *dquot) err = ext4_journal_stop(handle); if (!ret) ret = err; + + if (freeze_protected) + sb_end_intwrite(dquot->dq_sb); + return ret; } -- 2.39.5