From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B04F5C433F5 for ; Fri, 4 Mar 2022 02:21:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237320AbiCDCWB (ORCPT ); Thu, 3 Mar 2022 21:22:01 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34662 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231476AbiCDCWA (ORCPT ); Thu, 3 Mar 2022 21:22:00 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 13BD21704FB; Thu, 3 Mar 2022 18:21:14 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id A363F61785; Fri, 4 Mar 2022 02:21:13 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0981EC004E1; Fri, 4 Mar 2022 02:21:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1646360473; bh=NRULPurRWArfqoX9j/cTOT5shOU683ryvGRdna1/ZSA=; h=From:To:Cc:Subject:Date:From; b=FT3siMyN1CTlDnKcAtbJ5IircAhYNdNQPlfLl7nm3/6lornAnx2vmnpsXm/AFHFCr xRUG2/E8cmT2j6Q2GPjs8Gt/Fz27VW5Ry/Rp1+qnCdb5zsbgTYRov8of3Zv9eCKU9S T3nreASvLa32hr9jm7Gf1rphLvz1zmLGcV6ZA+jE30e1mmPeH9bzDJqV1AQef6CNL1 m/odgR9keHkl52e5z9xSc++Cmr+hAokgu8ibtk1/3qUHwt/PrftF2OdPWuY5FSCXng 5L5CEHuNFNzQPcjTuGeEHbVxXkz22LLNxEVWBKODRaSSM8+7dwa3uwkQE01AufdJF3 8T8d6XRNP7A5w== From: Jaegeuk Kim To: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Cc: Jaegeuk Kim Subject: [PATCH] vfs: do not try to evict inode when super is frozen Date: Thu, 3 Mar 2022 18:21:04 -0800 Message-Id: <20220304022104.2525009-1-jaegeuk@kernel.org> X-Mailer: git-send-email 2.35.1.616.g0bdcbb4464-goog MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Otherwise, we will get a deadlock. [freeze test] shrinkder freeze_super - pwercpu_down_write(SB_FREEZE_FS) - super_cache_scan - down_read(&sb->s_umount) - prune_icache_sb - dispose_list - evict - f2fs_evict_inode thaw_super - down_write(&sb->s_umount); - __percpu_down_read(SB_FREEZE_FS) Signed-off-by: Jaegeuk Kim --- fs/super.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/fs/super.c b/fs/super.c index 7af820ba5ad5..f7303d91f874 100644 --- a/fs/super.c +++ b/fs/super.c @@ -79,6 +79,12 @@ static unsigned long super_cache_scan(struct shrinker *shrink, if (!trylock_super(sb)) return SHRINK_STOP; + /* This prevents inode eviction that requires SB_FREEZE_FS. */ + if (sb->s_writers.frozen == SB_FREEZE_FS) { + up_read(&sb->s_umount); + return SHRINK_STOP; + } + if (sb->s_op->nr_cached_objects) fs_objects = sb->s_op->nr_cached_objects(sb, sc); -- 2.35.1.616.g0bdcbb4464-goog