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 picard.linux.it (picard.linux.it [213.254.12.146]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 3F7D9C87FD1 for ; Wed, 6 Aug 2025 09:27:01 +0000 (UTC) Received: from picard.linux.it (localhost [IPv6:::1]) by picard.linux.it (Postfix) with ESMTP id 835D03C7237 for ; Wed, 6 Aug 2025 11:26:59 +0200 (CEST) Received: from in-7.smtp.seeweb.it (in-7.smtp.seeweb.it [217.194.8.7]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (secp384r1) server-digest SHA384) (No client certificate requested) by picard.linux.it (Postfix) with ESMTPS id 9E2A03C033E for ; Wed, 6 Aug 2025 11:26:42 +0200 (CEST) Received: from smtp-out2.suse.de (smtp-out2.suse.de [IPv6:2a07:de40:b251:101:10:150:64:2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by in-7.smtp.seeweb.it (Postfix) with ESMTPS id 90C89200AD6 for ; Wed, 6 Aug 2025 11:26:41 +0200 (CEST) Received: from imap1.dmz-prg2.suse.org (imap1.dmz-prg2.suse.org [IPv6:2a07:de40:b281:104:10:150:64:97]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 483971F399; Wed, 6 Aug 2025 09:26:38 +0000 (UTC) Authentication-Results: smtp-out2.suse.de; none Received: from imap1.dmz-prg2.suse.org (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by imap1.dmz-prg2.suse.org (Postfix) with ESMTPS id 367D813AA8; Wed, 6 Aug 2025 09:26:38 +0000 (UTC) Received: from dovecot-director2.suse.de ([2a07:de40:b281:106:10:150:64:167]) by imap1.dmz-prg2.suse.org with ESMTPSA id ly7bC84fk2hDHwAAD6G6ig (envelope-from ); Wed, 06 Aug 2025 09:26:38 +0000 Date: Wed, 6 Aug 2025 11:27:23 +0200 From: Cyril Hrubis To: Li Wang Message-ID: References: <20190102131913.GA26215@rei.lan> <20250806074405.14890-1-liwang@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20250806074405.14890-1-liwang@redhat.com> X-Rspamd-Pre-Result: action=no action; module=replies; Message is reply to one we originated X-Rspamd-Server: rspamd1.dmz-prg2.suse.org X-Spamd-Result: default: False [-4.00 / 50.00]; REPLY(-4.00)[] X-Rspamd-Queue-Id: 483971F399 X-Rspamd-Pre-Result: action=no action; module=replies; Message is reply to one we originated X-Rspamd-Action: no action X-Virus-Scanned: clamav-milter 1.0.7 at in-7.smtp.seeweb.it X-Virus-Status: Clean Subject: Re: [LTP] [PATCH] tst_umount: Retry open() after umount to handle delayed device release X-BeenThere: ltp@lists.linux.it X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux Test Project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: rafael.tinoco@linaro.org, ltp@lists.linux.it Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: ltp-bounces+ltp=archiver.kernel.org@lists.linux.it Sender: "ltp" Hi! > Currently, tst_umount() in lib/tst_device.c tries to repeatedly umount() > a mount point, with a retry loop if it gets EBUSY. However, after umount() > reports success, devices (especially loop devices) can still be held open > by another process or kernel, delaying their actual release. This can lead > to race conditions when the next operation tries to reuse the device like > mkfs.ext3 error: This looks like working around a kernel bug to me. The umount() without MNT_DETACH should make the device reusable once the syscall returns back to the userspace. At least I wouldn't add this code to LTP unless kernel devs tells us that this broken behavior is to be expected. -- Cyril Hrubis chrubis@suse.cz -- Mailing list info: https://lists.linux.it/listinfo/ltp