From patchwork Mon Jul 29 09:46:58 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 1965916 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=KOb3xzVp; dkim-atps=neutral Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=patchwork.ozlabs.org) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4WXYS82pfSz1ybY for ; Mon, 29 Jul 2024 19:47:36 +1000 (AEST) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1sYMyP-0003Nv-Uw; Mon, 29 Jul 2024 05:47:21 -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 1sYMyN-0003Hb-Q4 for qemu-devel@nongnu.org; Mon, 29 Jul 2024 05:47:19 -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 1sYMyM-0004Yj-05 for qemu-devel@nongnu.org; Mon, 29 Jul 2024 05:47:19 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1722246437; 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=BdOLfUo1FinCPJEBrdvb3o1LkFOGtSrCp1ZUO0io0O8=; b=KOb3xzVpVV58/Cn9YAd5OiCJM7aeM2AMwm8h978aKut3Fw14RRXQVLQqQanuFXctn3/aXD 1GiYRQ+4dMW4LKzdQsVbncUACfcNVQyE3Di6xflSiTTCDPbjqUkjbBG0wIcqPUgsOyhsnI U6IGaUytGHu88qE/xNe1VyrdPkO2M3s= Received: from mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-375-QF7Dn0O1NGeIDUkglk6Qhw-1; Mon, 29 Jul 2024 05:47:12 -0400 X-MC-Unique: QF7Dn0O1NGeIDUkglk6Qhw-1 Received: from mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.17]) (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-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id B70B61955F66; Mon, 29 Jul 2024 09:47:11 +0000 (UTC) Received: from merkur.redhat.com (unknown [10.39.194.89]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 7D4F71955F3B; Mon, 29 Jul 2024 09:47:09 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Cc: kwolf@redhat.com, pbonzini@redhat.com, fam@euphon.net, stefanha@redhat.com, qemu-devel@nongnu.org Subject: [PATCH 1/4] scsi-disk: Use positive return value for status in dma_readv/writev Date: Mon, 29 Jul 2024 11:46:58 +0200 Message-ID: <20240729094702.50282-2-kwolf@redhat.com> In-Reply-To: <20240729094702.50282-1-kwolf@redhat.com> References: <20240729094702.50282-1-kwolf@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 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: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.125, 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_H3=-0.01, RCVD_IN_MSPIKE_WL=-0.01, 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+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org In some error cases, scsi_block_sgio_complete() never calls the passed callback, but directly completes the request. This leads to bugs because its error paths are not exact copies of what the callback would normally do. In preparation to fix this, allow passing positive return values to the callbacks that represent the status code that should be used to complete the request. scsi_handle_rw_error() already handles positive values for its ret parameter because scsi_block_sgio_complete() calls directly into it. Signed-off-by: Kevin Wolf --- hw/scsi/scsi-disk.c | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-) diff --git a/hw/scsi/scsi-disk.c b/hw/scsi/scsi-disk.c index a67092db6a..3ff6798bde 100644 --- a/hw/scsi/scsi-disk.c +++ b/hw/scsi/scsi-disk.c @@ -65,6 +65,10 @@ OBJECT_DECLARE_TYPE(SCSIDiskState, SCSIDiskClass, SCSI_DISK_BASE) struct SCSIDiskClass { SCSIDeviceClass parent_class; + /* + * Callbacks receive ret == 0 for success. Errors are represented either as + * negative errno values, or as positive SAM status codes. + */ DMAIOFunc *dma_readv; DMAIOFunc *dma_writev; bool (*need_fua_emulation)(SCSICommand *cmd); @@ -283,7 +287,7 @@ static bool scsi_disk_req_check_error(SCSIDiskReq *r, int ret, bool acct_failed) return true; } - if (ret < 0) { + if (ret != 0) { return scsi_handle_rw_error(r, ret, acct_failed); } @@ -360,7 +364,7 @@ static void scsi_write_do_fua(SCSIDiskReq *r) static void scsi_dma_complete_noio(SCSIDiskReq *r, int ret) { assert(r->req.aiocb == NULL); - if (scsi_disk_req_check_error(r, ret, false)) { + if (scsi_disk_req_check_error(r, ret, ret > 0)) { goto done; } @@ -385,9 +389,10 @@ static void scsi_dma_complete(void *opaque, int ret) assert(r->req.aiocb != NULL); r->req.aiocb = NULL; + /* ret > 0 is accounted for in scsi_disk_req_check_error() */ if (ret < 0) { block_acct_failed(blk_get_stats(s->qdev.conf.blk), &r->acct); - } else { + } else if (ret == 0) { block_acct_done(blk_get_stats(s->qdev.conf.blk), &r->acct); } scsi_dma_complete_noio(r, ret); @@ -403,7 +408,7 @@ static void scsi_read_complete_noio(SCSIDiskReq *r, int ret) qemu_get_current_aio_context()); assert(r->req.aiocb == NULL); - if (scsi_disk_req_check_error(r, ret, false)) { + if (scsi_disk_req_check_error(r, ret, ret > 0)) { goto done; } @@ -424,9 +429,10 @@ static void scsi_read_complete(void *opaque, int ret) assert(r->req.aiocb != NULL); r->req.aiocb = NULL; + /* ret > 0 is accounted for in scsi_disk_req_check_error() */ if (ret < 0) { block_acct_failed(blk_get_stats(s->qdev.conf.blk), &r->acct); - } else { + } else if (ret == 0) { block_acct_done(blk_get_stats(s->qdev.conf.blk), &r->acct); trace_scsi_disk_read_complete(r->req.tag, r->qiov.size); } @@ -534,7 +540,7 @@ static void scsi_write_complete_noio(SCSIDiskReq *r, int ret) qemu_get_current_aio_context()); assert (r->req.aiocb == NULL); - if (scsi_disk_req_check_error(r, ret, false)) { + if (scsi_disk_req_check_error(r, ret, ret > 0)) { goto done; } @@ -562,9 +568,10 @@ static void scsi_write_complete(void * opaque, int ret) assert (r->req.aiocb != NULL); r->req.aiocb = NULL; + /* ret > 0 is accounted for in scsi_disk_req_check_error() */ if (ret < 0) { block_acct_failed(blk_get_stats(s->qdev.conf.blk), &r->acct); - } else { + } else if (ret == 0) { block_acct_done(blk_get_stats(s->qdev.conf.blk), &r->acct); } scsi_write_complete_noio(r, ret); From patchwork Mon Jul 29 09:46:59 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 1965918 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=E2s1Jz+N; dkim-atps=neutral Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; 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Mon, 29 Jul 2024 09:47:15 +0000 (UTC) Received: from merkur.redhat.com (unknown [10.39.194.89]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 059A41955F40; Mon, 29 Jul 2024 09:47:11 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Cc: kwolf@redhat.com, pbonzini@redhat.com, fam@euphon.net, stefanha@redhat.com, qemu-devel@nongnu.org Subject: [PATCH 2/4] scsi-block: Don't skip callback for sgio error status/driver_status Date: Mon, 29 Jul 2024 11:46:59 +0200 Message-ID: <20240729094702.50282-3-kwolf@redhat.com> In-Reply-To: <20240729094702.50282-1-kwolf@redhat.com> References: <20240729094702.50282-1-kwolf@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 Received-SPF: pass client-ip=170.10.133.124; envelope-from=kwolf@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.125, 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_H4=-0.01, RCVD_IN_MSPIKE_WL=-0.01, 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+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Instead of calling into scsi_handle_rw_error() directly from scsi_block_sgio_complete() and skipping the normal callback, go through the normal cleanup path by calling the callback with a positive error value. The important difference here is not only that the code path is cleaner, but that the callbacks set r->req.aiocb = NULL. If we skip setting this and the error action is BLOCK_ERROR_ACTION_STOP, resuming the VM runs into an assertion failure in scsi_read_data() or scsi_write_data() because the dangling aiocb pointer is unexpected. Fixes: a108557bbf ("scsi: inline sg_io_sense_from_errno() into the callers.") Buglink: https://issues.redhat.com/browse/RHEL-50000 Signed-off-by: Kevin Wolf --- hw/scsi/scsi-disk.c | 10 ---------- 1 file changed, 10 deletions(-) diff --git a/hw/scsi/scsi-disk.c b/hw/scsi/scsi-disk.c index 3ff6798bde..6e1a5c98df 100644 --- a/hw/scsi/scsi-disk.c +++ b/hw/scsi/scsi-disk.c @@ -2832,16 +2832,6 @@ static void scsi_block_sgio_complete(void *opaque, int ret) } else { ret = io_hdr->status; } - - if (ret > 0) { - if (scsi_handle_rw_error(r, ret, true)) { - scsi_req_unref(&r->req); - return; - } - - /* Ignore error. */ - ret = 0; - } } req->cb(req->cb_opaque, ret); From patchwork Mon Jul 29 09:47:00 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 1965917 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=TR0zzB8Q; 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Mon, 29 Jul 2024 09:47:17 +0000 (UTC) Received: from merkur.redhat.com (unknown [10.39.194.89]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 4949E1955F40; Mon, 29 Jul 2024 09:47:15 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Cc: kwolf@redhat.com, pbonzini@redhat.com, fam@euphon.net, stefanha@redhat.com, qemu-devel@nongnu.org Subject: [PATCH 3/4] scsi-disk: Add warning comments that host_status errors take a shortcut Date: Mon, 29 Jul 2024 11:47:00 +0200 Message-ID: <20240729094702.50282-4-kwolf@redhat.com> In-Reply-To: <20240729094702.50282-1-kwolf@redhat.com> References: <20240729094702.50282-1-kwolf@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 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: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.125, 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_H3=-0.01, RCVD_IN_MSPIKE_WL=-0.01, 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+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org scsi_block_sgio_complete() has surprising behaviour in that there are error cases in which it directly completes the request and never calls the passed callback. In the current state of the code, this doesn't seem to result in bugs, but with future code changes, we must be careful to never rely on the callback doing some cleanup until this code smell is fixed. For now, just add warnings to make people aware of the trap. Signed-off-by: Kevin Wolf --- hw/scsi/scsi-disk.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/hw/scsi/scsi-disk.c b/hw/scsi/scsi-disk.c index 6e1a5c98df..69a195177e 100644 --- a/hw/scsi/scsi-disk.c +++ b/hw/scsi/scsi-disk.c @@ -68,6 +68,9 @@ struct SCSIDiskClass { /* * Callbacks receive ret == 0 for success. Errors are represented either as * negative errno values, or as positive SAM status codes. + * + * Beware: For errors returned in host_status, the function may directly + * complete the request and never call the callback. */ DMAIOFunc *dma_readv; DMAIOFunc *dma_writev; @@ -381,6 +384,7 @@ done: scsi_req_unref(&r->req); } +/* May not be called in all error cases, don't rely on cleanup here */ static void scsi_dma_complete(void *opaque, int ret) { SCSIDiskReq *r = (SCSIDiskReq *)opaque; @@ -421,6 +425,7 @@ done: scsi_req_unref(&r->req); } +/* May not be called in all error cases, don't rely on cleanup here */ static void scsi_read_complete(void *opaque, int ret) { SCSIDiskReq *r = (SCSIDiskReq *)opaque; @@ -560,6 +565,7 @@ done: scsi_req_unref(&r->req); } +/* May not be called in all error cases, don't rely on cleanup here */ static void scsi_write_complete(void * opaque, int ret) { SCSIDiskReq *r = (SCSIDiskReq *)opaque; @@ -2821,6 +2827,7 @@ static void scsi_block_sgio_complete(void *opaque, int ret) sg_io_hdr_t *io_hdr = &req->io_header; if (ret == 0) { + /* FIXME This skips calling req->cb() and any cleanup in it */ if (io_hdr->host_status != SCSI_HOST_OK) { scsi_req_complete_failed(&r->req, io_hdr->host_status); scsi_req_unref(&r->req); From patchwork Mon Jul 29 09:47:01 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Wolf X-Patchwork-Id: 1965920 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=KNQu1Mre; dkim-atps=neutral Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=patchwork.ozlabs.org) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4WXYT10DRgz1ybY for ; 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Mon, 29 Jul 2024 09:47:17 +0000 (UTC) From: Kevin Wolf To: qemu-block@nongnu.org Cc: kwolf@redhat.com, pbonzini@redhat.com, fam@euphon.net, stefanha@redhat.com, qemu-devel@nongnu.org Subject: [PATCH 4/4] scsi-disk: Always report RESERVATION_CONFLICT to guest Date: Mon, 29 Jul 2024 11:47:01 +0200 Message-ID: <20240729094702.50282-5-kwolf@redhat.com> In-Reply-To: <20240729094702.50282-1-kwolf@redhat.com> References: <20240729094702.50282-1-kwolf@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 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: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.125, 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_H3=-0.01, RCVD_IN_MSPIKE_WL=-0.01, 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+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org RESERVATION_CONFLICT is not a backend error, but indicates that the guest tried to make a request that it isn't allowed to execute. Pass the error to the guest so that it can decide what to do with it. Without this, if we stop the VM in response to a RESERVATION_CONFLICT, it can happen that the VM cannot be resumed any more because every attempt to resume it immediately runs into the same error and stops the VM again. One case that expects RESERVATION_CONFLICT errors to be visible in the guest is running the validation tests in Windows 2019's Failover Cluster Manager, which intentionally tries to execute invalid requests to see if they are properly rejected. Buglink: https://issues.redhat.com/browse/RHEL-50000 Signed-off-by: Kevin Wolf --- hw/scsi/scsi-disk.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/hw/scsi/scsi-disk.c b/hw/scsi/scsi-disk.c index 69a195177e..e173b238de 100644 --- a/hw/scsi/scsi-disk.c +++ b/hw/scsi/scsi-disk.c @@ -235,11 +235,17 @@ static bool scsi_handle_rw_error(SCSIDiskReq *r, int ret, bool acct_failed) } else { /* A passthrough command has completed with nonzero status. */ status = ret; - if (status == CHECK_CONDITION) { + switch (status) { + case CHECK_CONDITION: req_has_sense = true; error = scsi_sense_buf_to_errno(r->req.sense, sizeof(r->req.sense)); - } else { + break; + case RESERVATION_CONFLICT: + /* Don't apply the error policy, always report to the guest */ + break; + default: error = EINVAL; + break; } } @@ -249,8 +255,9 @@ static bool scsi_handle_rw_error(SCSIDiskReq *r, int ret, bool acct_failed) * are usually retried immediately, so do not post them to QMP and * do not account them as failed I/O. */ - if (req_has_sense && - scsi_sense_buf_is_guest_recoverable(r->req.sense, sizeof(r->req.sense))) { + if (!error || (req_has_sense && + scsi_sense_buf_is_guest_recoverable(r->req.sense, + sizeof(r->req.sense)))) { action = BLOCK_ERROR_ACTION_REPORT; acct_failed = false; } else {