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 B3504C369C2 for ; Fri, 25 Apr 2025 17:53:46 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1u8NEf-00011I-Vj; Fri, 25 Apr 2025 13:53:14 -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 1u8NEZ-0000rY-DO for qemu-devel@nongnu.org; Fri, 25 Apr 2025 13:53:07 -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 1u8NEX-0007PK-1z for qemu-devel@nongnu.org; Fri, 25 Apr 2025 13:53:07 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1745603584; 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=Kv9qDhyGRrIkUDKuFAfwQPGjpFR2P3l+wcvXDRuef2I=; b=XkRv2JLUxmOfpEIoNy/4XjuW8CyfEO4RltNfUQgwO8aZOx2PoitCgHvWgoWmIbAumUZsFf 7xyHONAg1PKLIfk4fRUPF0e4wS7iYN26AcLF71ycVUcsBMAl+Wxu74vIGz18F5GDUF5H/j VHN4dtbBY7RH0i1MX6GqEMIsMmmextQ= Received: from mx-prod-mc-06.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-519-0mD2A_sCPbimHnQoP3chSg-1; Fri, 25 Apr 2025 13:53:01 -0400 X-MC-Unique: 0mD2A_sCPbimHnQoP3chSg-1 X-Mimecast-MFC-AGG-ID: 0mD2A_sCPbimHnQoP3chSg_1745603580 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-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 28DCD180034E; Fri, 25 Apr 2025 17:53:00 +0000 (UTC) Received: from merkur.redhat.com (unknown [10.45.225.183]) by mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id C88E81800D97; Fri, 25 Apr 2025 17:52:58 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Cc: kwolf@redhat.com, qemu-devel@nongnu.org Subject: [PULL 2/4] block/io: skip head/tail requests on EINVAL Date: Fri, 25 Apr 2025 19:52:50 +0200 Message-ID: <20250425175252.316807-3-kwolf@redhat.com> In-Reply-To: <20250425175252.316807-1-kwolf@redhat.com> References: <20250425175252.316807-1-kwolf@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 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: -23 X-Spam_score: -2.4 X-Spam_bar: -- X-Spam_report: (-2.4 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.314, 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=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 From: Stefan Hajnoczi When guests send misaligned discard requests, the block layer breaks them up into a misaligned head, an aligned main body, and a misaligned tail. The file-posix block driver on Linux returns -EINVAL on misaligned discard requests. This causes bdrv_co_pdiscard() to fail and guests configured with werror=stop will pause. Add a special case for misaligned head/tail requests. Simply continue when EINVAL is encountered so that the aligned main body of the request can be completed and the guest is not paused. This is the best we can do when guest discard limits do not match the host discard limits. Fixes: https://issues.redhat.com/browse/RHEL-86032 Signed-off-by: Stefan Hajnoczi Reviewed-by: Hanna Czenczek Message-ID: <20250417150528.76470-3-stefanha@redhat.com> Reviewed-by: Kevin Wolf Signed-off-by: Kevin Wolf --- block/io.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/block/io.c b/block/io.c index 1ba8d1aeea..ccec11386b 100644 --- a/block/io.c +++ b/block/io.c @@ -3109,11 +3109,12 @@ int coroutine_fn bdrv_co_pdiscard(BdrvChild *child, int64_t offset, /* Invalidate the cached block-status data range if this discard overlaps */ bdrv_bsc_invalidate_range(bs, offset, bytes); - /* Discard is advisory, but some devices track and coalesce + /* + * Discard is advisory, but some devices track and coalesce * unaligned requests, so we must pass everything down rather than - * round here. Still, most devices will just silently ignore - * unaligned requests (by returning -ENOTSUP), so we must fragment - * the request accordingly. */ + * round here. Still, most devices reject unaligned requests with + * -EINVAL or -ENOTSUP, so we must fragment the request accordingly. + */ align = MAX(bs->bl.pdiscard_alignment, bs->bl.request_alignment); assert(align % bs->bl.request_alignment == 0); head = offset % align; @@ -3180,7 +3181,11 @@ int coroutine_fn bdrv_co_pdiscard(BdrvChild *child, int64_t offset, } } if (ret && ret != -ENOTSUP) { - goto out; + if (ret == -EINVAL && (offset % align != 0 || num % align != 0)) { + /* Silently skip rejected unaligned head/tail requests */ + } else { + goto out; /* bail out */ + } } offset += num; -- 2.49.0