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 80EE9C6379F for ; Tue, 7 Feb 2023 20:38:18 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pPUiv-0000Ly-UG; Tue, 07 Feb 2023 15:37:54 -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 1pPUiu-0000LC-No for qemu-devel@nongnu.org; Tue, 07 Feb 2023 15:37:52 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pPUis-0004Jd-7u for qemu-devel@nongnu.org; Tue, 07 Feb 2023 15:37:52 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1675802269; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ZHAcYrwLiKzwlv8ftTovcEzHuKiOJB+r7rwtfed0E/g=; b=MHhDtUm5DtoAaOnvrMPKd817h4tuQ9xMVr0mgUSqaUv0YCJtPe4AzNFGicSxmSdr+OeJAR eI2bsAiwn2CmHWVi3gMtpVFhqNO8UUTsjCO3myaACbgOLF5tlxBpIEXxmfIra3ksIQ8vhD QyZymKO1d8hQvZfc3xtKYKOKAVoLDV4= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-594-5iDMDd9UMuGp3_kT_rIsbA-1; Tue, 07 Feb 2023 15:37:45 -0500 X-MC-Unique: 5iDMDd9UMuGp3_kT_rIsbA-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 79B51811E6E; Tue, 7 Feb 2023 20:37:45 +0000 (UTC) Received: from localhost (unknown [10.39.192.15]) by smtp.corp.redhat.com (Postfix) with ESMTP id 6DE2A2166B29; Tue, 7 Feb 2023 20:37:44 +0000 (UTC) From: Stefan Hajnoczi To: qemu-devel@nongnu.org Cc: Kevin Wolf , Fiona Ebner , qemu-block@nongnu.org, Fam Zheng , Stefan Hajnoczi , Hanna Reitz , qemu-stable@nongnu.org, Eric Blake Subject: [PATCH v4 1/4] block: fix detect-zeroes= with BDRV_REQ_REGISTERED_BUF Date: Tue, 7 Feb 2023 15:37:16 -0500 Message-Id: <20230207203719.242926-2-stefanha@redhat.com> In-Reply-To: <20230207203719.242926-1-stefanha@redhat.com> References: <20230207203719.242926-1-stefanha@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 3.1 on 10.11.54.6 Received-SPF: pass client-ip=170.10.133.124; envelope-from=stefanha@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_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable 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 When a write request is converted into a write zeroes request by the detect-zeroes= feature, it is no longer associated with an I/O buffer. The BDRV_REQ_REGISTERED_BUF flag doesn't make sense without an I/O buffer and must be cleared because bdrv_co_do_pwrite_zeroes() fails with -EINVAL when it's set. Fiona Ebner bisected and diagnosed this QEMU 7.2 regression where writes containing zeroes to a blockdev with discard=unmap,detect-zeroes=unmap fail. Buglink: https://gitlab.com/qemu-project/qemu/-/issues/1404 Fixes: e8b6535533be ("block: add BDRV_REQ_REGISTERED_BUF request flag") Tested-by: Fiona Ebner Cc: qemu-stable@nongnu.org Reviewed-by: Eric Blake Reviewed-by: Hanna Czenczek Signed-off-by: Stefan Hajnoczi --- block/io.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/block/io.c b/block/io.c index 2dc0c13e41..d2be37b11e 100644 --- a/block/io.c +++ b/block/io.c @@ -1926,6 +1926,9 @@ static int coroutine_fn bdrv_aligned_pwritev(BdrvChild *child, if (bs->detect_zeroes == BLOCKDEV_DETECT_ZEROES_OPTIONS_UNMAP) { flags |= BDRV_REQ_MAY_UNMAP; } + + /* Can't use optimization hint with bufferless zero write */ + flags &= ~BDRV_REQ_REGISTERED_BUF; } if (ret < 0) { -- 2.39.1