From patchwork Wed Oct 21 20:15:14 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: 534061 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 20DBC14076B for ; Thu, 22 Oct 2015 07:46:28 +1100 (AEDT) Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 0040C1A3440 for ; Thu, 22 Oct 2015 07:46:28 +1100 (AEDT) X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Received: from e34.co.us.ibm.com (e34.co.us.ibm.com [32.97.110.152]) (using TLSv1 with cipher CAMELLIA256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 729411A09A7 for ; Thu, 22 Oct 2015 07:16:38 +1100 (AEDT) Received: from localhost by e34.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 21 Oct 2015 14:16:36 -0600 Received: from d03dlp01.boulder.ibm.com (9.17.202.177) by e34.co.us.ibm.com (192.168.1.134) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; Wed, 21 Oct 2015 14:16:34 -0600 X-IBM-Helo: d03dlp01.boulder.ibm.com X-IBM-MailFrom: mrochs@linux.vnet.ibm.com X-IBM-RcptTo: linuxppc-dev@lists.ozlabs.org Received: from b03cxnp07029.gho.boulder.ibm.com (b03cxnp07029.gho.boulder.ibm.com [9.17.130.16]) by d03dlp01.boulder.ibm.com (Postfix) with ESMTP id 705431FF002D for ; Wed, 21 Oct 2015 14:04:45 -0600 (MDT) Received: from d03av02.boulder.ibm.com (d03av02.boulder.ibm.com [9.17.195.168]) by b03cxnp07029.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id t9LKGXS22359716 for ; Wed, 21 Oct 2015 13:16:33 -0700 Received: from d03av02.boulder.ibm.com (localhost [127.0.0.1]) by d03av02.boulder.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id t9LKGWBT008396 for ; Wed, 21 Oct 2015 14:16:33 -0600 Received: from p8tul1-build.aus.stglabs.ibm.com (als141206.austin.ibm.com [9.3.141.206]) by d03av02.boulder.ibm.com (8.14.4/8.14.4/NCO v10.0 AVin) with ESMTP id t9LKGVVS008234; Wed, 21 Oct 2015 14:16:31 -0600 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 v6 27/37] cxlflash: Fix to prevent stale AFU RRQ Date: Wed, 21 Oct 2015 15:15:14 -0500 Message-Id: <1445458514-58777-1-git-send-email-mrochs@linux.vnet.ibm.com> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1445458134-63197-1-git-send-email-mrochs@linux.vnet.ibm.com> References: <1445458134-63197-1-git-send-email-mrochs@linux.vnet.ibm.com> X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15102120-0017-0000-0000-00000EE2B681 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 Reviewed-by: Tomas Henzl --- 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 eeb1c47..c77cb92 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];