From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Matthew R. Ochs" 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> References: <1443222593-8828-1-git-send-email-mrochs@linux.vnet.ibm.com> Return-path: Received: from e18.ny.us.ibm.com ([129.33.205.208]:52993 "EHLO e18.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754509AbbIYXTr (ORCPT ); Fri, 25 Sep 2015 19:19:47 -0400 Received: from localhost by e18.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 25 Sep 2015 19:19:47 -0400 Received: from b01cxnp22035.gho.pok.ibm.com (b01cxnp22035.gho.pok.ibm.com [9.57.198.25]) by d01dlp02.pok.ibm.com (Postfix) with ESMTP id 12A4C6E8045 for ; Fri, 25 Sep 2015 19:11:29 -0400 (EDT) Received: from d01av01.pok.ibm.com (d01av01.pok.ibm.com [9.56.224.215]) by b01cxnp22035.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id t8PNJjQq64487608 for ; Fri, 25 Sep 2015 23:19:45 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 t8PNJiXu016735 for ; Fri, 25 Sep 2015 19:19:45 -0400 In-Reply-To: <1443222593-8828-1-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 , linuxppc-dev@lists.ozlabs.org, "Manoj N. Kumar" 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 --- 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]; -- 2.1.0