From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rameshwar Prasad Sahu Subject: [PATCH v2] ata: fixes kernel crash while tracing ata_eh_link_autopsy event Date: Thu, 2 Nov 2017 16:31:07 +0530 Message-ID: <1509620467-6679-1-git-send-email-rsahu@apm.com> Return-path: Sender: linux-scsi-owner@vger.kernel.org To: olof@lixom.net, tj@kernel.org, arnd@arndb.de Cc: linux-scsi@vger.kernel.org, linux-ide@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, mlangsdo@redhat.com, jcm@redhat.com, patches@apm.com, Rameshwar Prasad Sahu List-Id: devicetree@vger.kernel.org When tracing ata link error event, the kernel crashes when the disk is removed due to NULL pointer access by trace_ata_eh_link_autopsy API. This occurs as the dev is NULL when the disk disappeared. This patch fixes this crash by calling trace_ata_eh_link_autopsy only if "dev" is not NULL. v2 changes: Removed direct passing "link" pointer instead of "dev" in trace API. Signed-off-by: Rameshwar Prasad Sahu --- drivers/ata/libata-eh.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c index e4effef..ea20e0e 100644 --- a/drivers/ata/libata-eh.c +++ b/drivers/ata/libata-eh.c @@ -2264,8 +2264,8 @@ static void ata_eh_link_autopsy(struct ata_link *link) if (dev->flags & ATA_DFLAG_DUBIOUS_XFER) eflags |= ATA_EFLAG_DUBIOUS_XFER; ehc->i.action |= ata_eh_speed_down(dev, eflags, all_err_mask); + trace_ata_eh_link_autopsy(dev, ehc->i.action, all_err_mask); } - trace_ata_eh_link_autopsy(dev, ehc->i.action, all_err_mask); DPRINTK("EXIT\n"); } -- 1.7.1