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 1372FC28B28 for ; Thu, 13 Mar 2025 10:18:16 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1tsfdJ-0002SO-MW; Thu, 13 Mar 2025 06:17:45 -0400 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 1tsfdD-0002Q7-5M for qemu-devel@nongnu.org; Thu, 13 Mar 2025 06:17:40 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1tsfdB-0001wn-G2 for qemu-devel@nongnu.org; Thu, 13 Mar 2025 06:17:38 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1741861054; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=MA9dE9T5xInzh/TpnlrKHFzJCyAk8i+o0W7aV7g8P74=; b=GaKtYevwK6VzB7xoUMULthx8edIb9FYHBqQek0PM2p2A2oDLUuGBylKOXbOEeo3YMjEl4g uyNevkq46rxRcf+dXfSAp+QBCUogWgSZetB3u5N/E7amGCkKdewAxydGHmebZa0vXHYb6s aVDSl+4Ftj7fIFLEeYoVNwOgwKR8SDM= Received: from mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-639-LMzHuBJCPGW1iDYKOxaOHw-1; Thu, 13 Mar 2025 06:17:31 -0400 X-MC-Unique: LMzHuBJCPGW1iDYKOxaOHw-1 X-Mimecast-MFC-AGG-ID: LMzHuBJCPGW1iDYKOxaOHw_1741861050 Received: from mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.93]) (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 mx-prod-mc-08.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 75EF31801A12; Thu, 13 Mar 2025 10:17:29 +0000 (UTC) Received: from redhat.com (unknown [10.45.225.21]) by mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 409B218001E9; Thu, 13 Mar 2025 10:17:26 +0000 (UTC) Date: Thu, 13 Mar 2025 11:17:23 +0100 From: Kevin Wolf To: Markus Armbruster Cc: qemu-devel@nongnu.org, qemu-block@nongnu.org, hreitz@redhat.com, vsementsov@yandex-team.ru Subject: Re: [PATCH] block: Fix bdrv_activate() not to fail without medium Message-ID: References: <20250312143758.1660177-1-armbru@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250312143758.1660177-1-armbru@redhat.com> X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 Received-SPF: pass client-ip=170.10.129.124; envelope-from=kwolf@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 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 Am 12.03.2025 um 15:37 hat Markus Armbruster geschrieben: > bdrv_activate() returns failure without setting an error when > !bs->drv. This is suspicious. Turns out it used to succeed then, > until commit 5416645fcf82 changed it to return -ENOMEDIUM. > > Return zero instead. > > Fixes: 5416645fcf82 (block: return error-code from bdrv_invalidate_cache) > Signed-off-by: Markus Armbruster The commit message sounds more theoretical. Did you find this only by code inspection? Do we know what the effect on real-world cases is, so we could add a sentence about it to the commit message? Maybe we could even have a qemu-iotests case to show the effect? I absolutely agree that returning -ENOMEDIUM while not setting errp is wrong. But without an example of what is affected, it's not obvious to me which part of it needs to be fixed. Kevin