From patchwork Wed Oct 21 20:16:00 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: 534067 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 8A738141309 for ; Thu, 22 Oct 2015 07:53:38 +1100 (AEDT) Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 58F281A301A for ; Thu, 22 Oct 2015 07:53:38 +1100 (AEDT) X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Received: from e18.ny.us.ibm.com (e18.ny.us.ibm.com [129.33.205.208]) (using TLSv1 with cipher CAMELLIA256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 6C45B1A0BE0 for ; Thu, 22 Oct 2015 07:17:22 +1100 (AEDT) Received: from localhost by e18.ny.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Wed, 21 Oct 2015 16:17:19 -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 b01cxnp22033.gho.pok.ibm.com (b01cxnp22033.gho.pok.ibm.com [9.57.198.23]) by d01dlp03.pok.ibm.com (Postfix) with ESMTP id F1DE9C9003C for ; Wed, 21 Oct 2015 16:05:29 -0400 (EDT) Received: from d01av03.pok.ibm.com (d01av03.pok.ibm.com [9.56.224.217]) by b01cxnp22033.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id t9LKHI4L58065030 for ; Wed, 21 Oct 2015 20:17:18 GMT Received: from d01av03.pok.ibm.com (localhost [127.0.0.1]) by d01av03.pok.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id t9LKHHKO009739 for ; Wed, 21 Oct 2015 16:17:18 -0400 Received: from p8tul1-build.aus.stglabs.ibm.com (als141206.austin.ibm.com [9.3.141.206]) by d01av03.pok.ibm.com (8.14.4/8.14.4/NCO v10.0 AVin) with ESMTP id t9LKHGaU009686; Wed, 21 Oct 2015 16:17:16 -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 v6 33/37] cxlflash: Fix to avoid leaving dangling interrupt resources Date: Wed, 21 Oct 2015 15:16:00 -0500 Message-Id: <1445458560-61693-1-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: 15102120-0045-0000-0000-000001FC3F18 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" When running with an unsupported AFU, the cxlflash driver fails the probe. When the driver is removed, the following Oops is encountered on a show_interrupts() thread: Call Trace: [c000001fba5a7a10] [0000000000000003] 0x3 (unreliable) [c000001fba5a7a60] [c00000000053dcf4] vsnprintf+0x204/0x4c0 [c000001fba5a7ae0] [c00000000030045c] seq_vprintf+0x5c/0xd0 [c000001fba5a7b20] [c00000000030051c] seq_printf+0x4c/0x60 [c000001fba5a7b50] [c00000000013e140] show_interrupts+0x370/0x4f0 [c000001fba5a7c10] [c0000000002ff898] seq_read+0xe8/0x530 [c000001fba5a7ca0] [c00000000035d5c0] proc_reg_read+0xb0/0x110 [c000001fba5a7cf0] [c0000000002ca74c] __vfs_read+0x6c/0x180 [c000001fba5a7d90] [c0000000002cb464] vfs_read+0xa4/0x1c0 [c000001fba5a7de0] [c0000000002cc51c] SyS_read+0x6c/0x110 [c000001fba5a7e30] [c000000000009204] system_call+0x38/0xb4 The Oops is due to not cleaning up correctly on the unsupported AFU error path, leaving various allocated and registered resources. In this case, interrupts are in a semi-allocated/registered state, which the show_interrupts() thread attempts to use. To fix, the cleanup logic in init_afu() is consolidated to error gates at the bottom of the function and the appropriate goto is added to each error path. As a mini side fix while refactoring in this routine, the else statement following the AFU version evaluation is eliminated as it is not needed. Signed-off-by: Matthew R. Ochs Acked-by: Manoj Kumar Reviewed-by: Andrew Donnellan Reviewed-by: Tomas Henzl --- drivers/scsi/cxlflash/main.c | 28 ++++++++++++++++------------ 1 file changed, 16 insertions(+), 12 deletions(-) diff --git a/drivers/scsi/cxlflash/main.c b/drivers/scsi/cxlflash/main.c index 998373e..c152703 100644 --- a/drivers/scsi/cxlflash/main.c +++ b/drivers/scsi/cxlflash/main.c @@ -1721,15 +1721,14 @@ static int init_afu(struct cxlflash_cfg *cfg) if (rc) { dev_err(dev, "%s: call to init_mc failed, rc=%d!\n", __func__, rc); - goto err1; + goto out; } /* Map the entire MMIO space of the AFU */ afu->afu_map = cxl_psa_map(cfg->mcctx); if (!afu->afu_map) { - rc = -ENOMEM; - term_mc(cfg, UNDO_START); dev_err(dev, "%s: call to cxl_psa_map failed!\n", __func__); + rc = -ENOMEM; goto err1; } @@ -1743,19 +1742,17 @@ static int init_afu(struct cxlflash_cfg *cfg) "interface version 0x%llx\n", afu->version, afu->interface_version); rc = -EINVAL; - goto err1; - } else - pr_debug("%s: afu version %s, interface version 0x%llX\n", - __func__, afu->version, afu->interface_version); + goto err2; + } + + pr_debug("%s: afu version %s, interface version 0x%llX\n", __func__, + afu->version, afu->interface_version); rc = start_afu(cfg); if (rc) { dev_err(dev, "%s: call to start_afu failed, rc=%d!\n", __func__, rc); - term_mc(cfg, UNDO_START); - cxl_psa_unmap((void __iomem *)afu->afu_map); - afu->afu_map = NULL; - goto err1; + goto err2; } afu_err_intr_init(cfg->afu); @@ -1763,9 +1760,16 @@ static int init_afu(struct cxlflash_cfg *cfg) /* Restore the LUN mappings */ cxlflash_restore_luntable(cfg); -err1: +out: pr_debug("%s: returning rc=%d\n", __func__, rc); return rc; + +err2: + cxl_psa_unmap((void __iomem *)afu->afu_map); + afu->afu_map = NULL; +err1: + term_mc(cfg, UNDO_START); + goto out; } /**