From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Matthew R. Ochs" 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> References: <1445458134-63197-1-git-send-email-mrochs@linux.vnet.ibm.com> Return-path: Received: from e32.co.us.ibm.com ([32.97.110.150]:40055 "EHLO e32.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964801AbbJUUQi (ORCPT ); Wed, 21 Oct 2015 16:16:38 -0400 Received: from localhost by e32.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 21 Oct 2015 14:16:37 -0600 Received: from b03cxnp08028.gho.boulder.ibm.com (b03cxnp08028.gho.boulder.ibm.com [9.17.130.20]) by d03dlp03.boulder.ibm.com (Postfix) with ESMTP id 96E3419D8042 for ; Wed, 21 Oct 2015 14:04:44 -0600 (MDT) Received: from d03av02.boulder.ibm.com (d03av02.boulder.ibm.com [9.17.195.168]) by b03cxnp08028.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id t9LKFEKi5308762 for ; Wed, 21 Oct 2015 13:15:14 -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 t9LKGWBb008396 for ; Wed, 21 Oct 2015 14:16:33 -0600 In-Reply-To: <1445458134-63197-1-git-send-email-mrochs@linux.vnet.ibm.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: linux-scsi@vger.kernel.org, James Bottomley , "Nicholas A. Bellinger" , Brian King , Ian Munsie , Daniel Axtens , Andrew Donnellan , Tomas Henzl , David Laight Cc: Michael Neuling , "Manoj N. Kumar" , linuxppc-dev@lists.ozlabs.org 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 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]; -- 2.1.0