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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E8178C433F5 for ; Mon, 23 May 2022 18:09:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243219AbiEWSJw (ORCPT ); Mon, 23 May 2022 14:09:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35364 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243457AbiEWRiO (ORCPT ); Mon, 23 May 2022 13:38:14 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B90A18DDC4; Mon, 23 May 2022 10:32:20 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 4F73EB81210; Mon, 23 May 2022 17:30:51 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5BBBAC3411A; Mon, 23 May 2022 17:30:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1653327050; bh=Q6WGn+T2IYOJX+pYvJtK4Xq4x5ALfQD1/9ZqxdvFrkU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cmbeNHO9I4g/t5asLmNS+s9sTtpiGLXRbwI4POo8oGeLU3ggaaDL2L5WhXIaVJCuX Dj7nkz5WmKsF1Os7jeg60+ZETs9lnN/lkSi1iOITZqIOvFGy7gAG10j4JH9mOcBwP5 LyBNeCRC6czkIohFDbADnzR35cXT+kLXZ/aCIn+g= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Hannes Reinecke , Krishna Kant , Seamus Connor , Brian Bunker , "Martin K. Petersen" , Sasha Levin Subject: [PATCH 5.17 133/158] scsi: scsi_dh_alua: Properly handle the ALUA transitioning state Date: Mon, 23 May 2022 19:04:50 +0200 Message-Id: <20220523165852.430311385@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220523165830.581652127@linuxfoundation.org> References: <20220523165830.581652127@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Brian Bunker [ Upstream commit 6056a92ceb2a7705d61df7ec5370548e96aee258 ] The handling of the ALUA transitioning state is currently broken. When a target goes into this state, it is expected that the target is allowed to stay in this state for the implicit transition timeout without a path failure. The handler has this logic, but it gets skipped currently. When the target transitions, there is in-flight I/O from the initiator. The first of these responses from the target will be a unit attention letting the initiator know that the ALUA state has changed. The remaining in-flight I/Os, before the initiator finds out that the portal state has changed, will return not ready, ALUA state is transitioning. The portal state will change to SCSI_ACCESS_STATE_TRANSITIONING. This will lead to all new I/O immediately failing the path unexpectedly. The path failure happens in less than a second instead of the expected successes until the transition timer is exceeded. Allow I/Os to continue while the path is in the ALUA transitioning state. The handler already takes care of a target that stays in the transitioning state for too long by changing the state to ALUA state standby once the transition timeout is exceeded at which point the path will fail. Link: https://lore.kernel.org/r/CAHZQxy+4sTPz9+pY3=7VJH+CLUJsDct81KtnR2be8ycN5mhqTg@mail.gmail.com Reviewed-by: Hannes Reinecke Acked-by: Krishna Kant Acked-by: Seamus Connor Signed-off-by: Brian Bunker Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin --- drivers/scsi/device_handler/scsi_dh_alua.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c index 37d06f993b76..1d9be771f3ee 100644 --- a/drivers/scsi/device_handler/scsi_dh_alua.c +++ b/drivers/scsi/device_handler/scsi_dh_alua.c @@ -1172,9 +1172,8 @@ static blk_status_t alua_prep_fn(struct scsi_device *sdev, struct request *req) case SCSI_ACCESS_STATE_OPTIMAL: case SCSI_ACCESS_STATE_ACTIVE: case SCSI_ACCESS_STATE_LBA: - return BLK_STS_OK; case SCSI_ACCESS_STATE_TRANSITIONING: - return BLK_STS_AGAIN; + return BLK_STS_OK; default: req->rq_flags |= RQF_QUIET; return BLK_STS_IOERR; -- 2.35.1