From: Rameshwar Prasad Sahu Date: Thu, 2 Nov 2017 11:01:07 +0000 (+0530) Subject: ata: fixes kernel crash while tracing ata_eh_link_autopsy event X-Git-Tag: v4.15-rc1~100^2~2 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=f1601113ddc0339a745e702f4fb1ca37d4875e65;p=platform%2Fkernel%2Flinux-exynos.git ata: fixes kernel crash while tracing ata_eh_link_autopsy event 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 Signed-off-by: Tejun Heo Fixes: 255c03d15a29 ("libata: Add tracepoints") Cc: stable@vger.kernel.org # v4.1+ --- diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c index e070fe8267ff..6d45bfa6d611 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"); }