From patchwork Fri Sep 25 23:19:04 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Matthew R. Ochs" X-Patchwork-Id: 523052 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [103.22.144.68]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 048B71402A2 for ; Sat, 26 Sep 2015 09:45:08 +1000 (AEST) Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id D453D1A3DF2 for ; Sat, 26 Sep 2015 09:45:07 +1000 (AEST) X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Received: from e19.ny.us.ibm.com (e19.ny.us.ibm.com [129.33.205.209]) (using TLSv1 with cipher CAMELLIA256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 099FC1A2AB1 for ; Sat, 26 Sep 2015 09:19:48 +1000 (AEST) Received: from localhost by e19.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 25 Sep 2015 19:19:46 -0400 Received: from d01dlp01.pok.ibm.com (9.56.250.166) by e19.ny.us.ibm.com (146.89.104.206) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; Fri, 25 Sep 2015 19:19:45 -0400 X-IBM-Helo: d01dlp01.pok.ibm.com X-IBM-MailFrom: mrochs@linux.vnet.ibm.com X-IBM-RcptTo: linuxppc-dev@lists.ozlabs.org Received: from b01cxnp22034.gho.pok.ibm.com (b01cxnp22034.gho.pok.ibm.com [9.57.198.24]) by d01dlp01.pok.ibm.com (Postfix) with ESMTP id 0A04738C803B for ; Fri, 25 Sep 2015 19:19:45 -0400 (EDT) Received: from d01av01.pok.ibm.com (d01av01.pok.ibm.com [9.56.224.215]) by b01cxnp22034.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id t8PNJifw55902366 for ; Fri, 25 Sep 2015 23:19:44 GMT Received: from d01av01.pok.ibm.com (localhost [127.0.0.1]) by d01av01.pok.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id t8PNJiXm016735 for ; Fri, 25 Sep 2015 19:19:44 -0400 Received: from p8tul1-build.aus.stglabs.ibm.com (als141206.austin.ibm.com [9.3.141.206]) by d01av01.pok.ibm.com (8.14.4/8.14.4/NCO v10.0 AVin) with ESMTP id t8PNJgVx016675; Fri, 25 Sep 2015 19:19:42 -0400 From: "Matthew R. Ochs" To: linux-scsi@vger.kernel.org, James Bottomley , "Nicholas A. Bellinger" , Brian King , Ian Munsie , Daniel Axtens , Andrew Donnellan , Tomas Henzl , David Laight Subject: [PATCH v4 27/32] cxlflash: Fix to prevent stale AFU RRQ Date: Fri, 25 Sep 2015 18:19:04 -0500 Message-Id: <1443223144-9962-1-git-send-email-mrochs@linux.vnet.ibm.com> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1443222593-8828-1-git-send-email-mrochs@linux.vnet.ibm.com> References: <1443222593-8828-1-git-send-email-mrochs@linux.vnet.ibm.com> X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15092523-0057-0000-0000-000001A9C6ED X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Michael Neuling , "Manoj N. Kumar" , linuxppc-dev@lists.ozlabs.org MIME-Version: 1.0 Errors-To: linuxppc-dev-bounces+patchwork-incoming=ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" Following an adapter reset, the AFU RRQ that resides in host memory holds stale data. This can lead to a condition where the RRQ interrupt handler tries to process stale entries and/or endlessly loops due to an out of sync generation bit. To fix, the AFU RRQ in host memory needs to be cleared after each reset. Signed-off-by: Matthew R. Ochs Signed-off-by: Manoj N. Kumar Reviewed-by: Brian King Reviewed-by: Daniel Axtens --- drivers/scsi/cxlflash/main.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c index 24aedfb..ab11ee6 100644 --- a/drivers/scsi/cxlflash/main.c +++ b/drivers/scsi/cxlflash/main.c @@ -1598,6 +1598,9 @@ static int start_afu(struct cxlflash_cfg *cfg) init_pcr(cfg); + /* After an AFU reset, RRQ entries are stale, clear them */ + memset(&afu->rrq_entry, 0, sizeof(afu->rrq_entry)); + /* Initialize RRQ pointers */ afu->hrrq_start = &afu->rrq_entry[0]; afu->hrrq_end = &afu->rrq_entry[NUM_RRQ_ENTRY - 1];