From patchwork Fri Sep 25 23:17:16 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: 523045 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id B93121401F6 for ; Sat, 26 Sep 2015 09:37:49 +1000 (AEST) Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 9DB991A3916 for ; Sat, 26 Sep 2015 09:37:49 +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 268971A1E34 for ; Sat, 26 Sep 2015 09:17:58 +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 19:17:56 -0400 Received: from d01dlp03.pok.ibm.com (9.56.250.168) 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 19:17:55 -0400 X-IBM-Helo: d01dlp03.pok.ibm.com X-IBM-MailFrom: mrochs@linux.vnet.ibm.com X-IBM-RcptTo: linuxppc-dev@lists.ozlabs.org Received: from b01cxnp23033.gho.pok.ibm.com (b01cxnp23033.gho.pok.ibm.com [9.57.198.28]) by d01dlp03.pok.ibm.com (Postfix) with ESMTP id 93852C90045 for ; Fri, 25 Sep 2015 19:08:57 -0400 (EDT) Received: from d01av04.pok.ibm.com (d01av04.pok.ibm.com [9.56.224.64]) by b01cxnp23033.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id t8PNHsYF62783572 for ; Fri, 25 Sep 2015 23:17:54 GMT Received: from d01av04.pok.ibm.com (localhost [127.0.0.1]) by d01av04.pok.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id t8PNHr8K029977 for ; Fri, 25 Sep 2015 19:17:54 -0400 Received: from p8tul1-build.aus.stglabs.ibm.com (als141206.austin.ibm.com [9.3.141.206]) by d01av04.pok.ibm.com (8.14.4/8.14.4/NCO v10.0 AVin) with ESMTP id t8PNHqmV029932; Fri, 25 Sep 2015 19:17:52 -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 20/32] cxlflash: Fix to prevent workq from accessing freed memory Date: Fri, 25 Sep 2015 18:17:16 -0500 Message-Id: <1443223036-9694-1-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: 15092523-0057-0000-0000-000001A9C623 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" The workq can process work in parallel with a remove event, leading to a condition where the workq handler can access freed memory. To remedy, the workq should be terminated prior to freeing memory. Move the termination call earlier in remove and use cancel_work_sync() instead of flush_work() as there is not a need to process any scheduled work when shutting down. Signed-off-by: Matthew R. Ochs Signed-off-by: Manoj N. Kumar Reviewed-by: Brian King --- drivers/scsi/cxlflash/main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c index 0bb6629..fada355 100644 --- a/drivers/scsi/cxlflash/main.c +++ b/drivers/scsi/cxlflash/main.c @@ -736,11 +736,11 @@ static void cxlflash_remove(struct pci_dev *pdev) /* Fall through */ case INIT_STATE_AFU: term_afu(cfg); + cancel_work_sync(&cfg->work_q); case INIT_STATE_PCI: pci_release_regions(cfg->dev); pci_disable_device(pdev); case INIT_STATE_NONE: - flush_work(&cfg->work_q); free_mem(cfg); scsi_host_put(cfg->host); break;