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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (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 97862C4828F for ; Fri, 2 Feb 2024 15:11:57 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rVvCG-0005rq-Jb; Fri, 02 Feb 2024 10:11:16 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rVvCF-0005rE-Fj for qemu-devel@nongnu.org; Fri, 02 Feb 2024 10:11:15 -0500 Received: from smtp-out1.suse.de ([2a07:de40:b251:101:10:150:64:1]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1rVvCE-0001M6-1E for qemu-devel@nongnu.org; Fri, 02 Feb 2024 10:11:15 -0500 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-out1.suse.de (Postfix) with ESMTPS id A488321A04; Fri, 2 Feb 2024 15:11:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1706886672; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Khk/eqE/ZU6GiguRMAKHVNh1YhqZBPyvzK++566dyi0=; b=ACIjbDgQs5vLiQcvmND4cC1cyBtKMqGx38qSqYUpNQqdTzmPJ9h9ZGT/XiGsC4HI7eO2sx tWmyphMwamLVXw4ncHemUeStE5ai+QV8bqmDMwrnoA2aAbKTXWrhTLamOZWrMwJKdIvX0y McCwCMgQ5FSFmESkKgW9nb+cWR6AluA= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1706886672; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Khk/eqE/ZU6GiguRMAKHVNh1YhqZBPyvzK++566dyi0=; b=VOIgrjjGUcW1wM9Sn5JAvHbcwzn0XZ4SzDvotO2PXXLigWdTOY05DCEC+gwe4J8U3hYbxi nZ/X+qUR/pdIUgDw== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1706886672; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Khk/eqE/ZU6GiguRMAKHVNh1YhqZBPyvzK++566dyi0=; b=ACIjbDgQs5vLiQcvmND4cC1cyBtKMqGx38qSqYUpNQqdTzmPJ9h9ZGT/XiGsC4HI7eO2sx tWmyphMwamLVXw4ncHemUeStE5ai+QV8bqmDMwrnoA2aAbKTXWrhTLamOZWrMwJKdIvX0y McCwCMgQ5FSFmESkKgW9nb+cWR6AluA= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1706886672; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Khk/eqE/ZU6GiguRMAKHVNh1YhqZBPyvzK++566dyi0=; b=VOIgrjjGUcW1wM9Sn5JAvHbcwzn0XZ4SzDvotO2PXXLigWdTOY05DCEC+gwe4J8U3hYbxi nZ/X+qUR/pdIUgDw== 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 25787139AB; Fri, 2 Feb 2024 15:11:11 +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 FUWfNw8GvWXULAAAD6G6ig (envelope-from ); Fri, 02 Feb 2024 15:11:11 +0000 From: Fabiano Rosas To: =?utf-8?Q?C=C3=A9dric?= Le Goater , qemu-devel@nongnu.org Cc: Peter Xu Subject: Re: [PATCH 2/2] migration: Fix return-path thread exit In-Reply-To: References: <20240201184853.890471-1-clg@redhat.com> <20240201184853.890471-3-clg@redhat.com> <8734ubhqr9.fsf@suse.de> Date: Fri, 02 Feb 2024 12:11:09 -0300 Message-ID: <87zfwihpf6.fsf@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Authentication-Results: smtp-out1.suse.de; dkim=pass header.d=suse.de header.s=susede2_rsa header.b=ACIjbDgQ; dkim=pass header.d=suse.de header.s=susede2_ed25519 header.b=VOIgrjjG X-Rspamd-Server: rspamd2.dmz-prg2.suse.org X-Spamd-Result: default: False [-4.02 / 50.00]; ARC_NA(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; R_DKIM_ALLOW(-0.20)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; SPAMHAUS_XBL(0.00)[2a07:de40:b281:104:10:150:64:97:from]; FROM_HAS_DN(0.00)[]; RCPT_COUNT_THREE(0.00)[3]; TO_DN_SOME(0.00)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; MIME_GOOD(-0.10)[text/plain]; NEURAL_HAM_LONG(-1.00)[-1.000]; DWL_DNSWL_MED(-2.00)[suse.de:dkim]; BAYES_HAM(-0.51)[80.08%]; RCVD_COUNT_THREE(0.00)[3]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; DKIM_TRACE(0.00)[suse.de:+]; MX_GOOD(-0.01)[]; DBL_BLOCKED_OPENRESOLVER(0.00)[suse.de:dkim]; FUZZY_BLOCKED(0.00)[rspamd.com]; FROM_EQ_ENVFROM(0.00)[]; MIME_TRACE(0.00)[0:+]; NEURAL_HAM_SHORT(-0.20)[-1.000]; RCVD_TLS_ALL(0.00)[]; MID_RHS_MATCH_FROM(0.00)[] X-Rspamd-Queue-Id: A488321A04 Received-SPF: pass client-ip=2a07:de40:b251:101:10:150:64:1; envelope-from=farosas@suse.de; helo=smtp-out1.suse.de X-Spam_score_int: -43 X-Spam_score: -4.4 X-Spam_bar: ---- X-Spam_report: (-4.4 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_MED=-2.3, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org C=C3=A9dric Le Goater writes: > On 2/2/24 15:42, Fabiano Rosas wrote: >> C=C3=A9dric Le Goater writes: >>=20 >>> In case of error, close_return_path_on_source() can perform a shutdown >>> to exit the return-path thread. However, in migrate_fd_cleanup(), >>> 'to_dst_file' is closed before calling close_return_path_on_source() >>> and the shutdown fails, leaving the source and destination waiting for >>> an event to occur. >>=20 >> At close_return_path_on_source, qemu_file_shutdown() and checking >> ms->to_dst_file are done under the qemu_file_lock, so how could >> migrate_fd_cleanup() have cleared the pointer but the ms->to_dst_file >> check have passed? > > This is not a locking issue, it's much simpler. migrate_fd_cleanup() > clears the ms->to_dst_file pointer and closes the QEMUFile and then > calls close_return_path_on_source() which then tries to use resources > which are not available anymore. I'm missing something here. Which resources? I assume you're talking about this: WITH_QEMU_LOCK_GUARD(&ms->qemu_file_lock) { if (ms->to_dst_file && ms->rp_state.from_dst_file && qemu_file_get_error(ms->to_dst_file)) { qemu_file_shutdown(ms->rp_state.from_dst_file); } } How do we get past the 'if (ms->to_dst_file)'?