Patch "ata: fixes kernel crash while tracing ata_eh_link_autopsy event" has been added to the 4.9-stable tree

This is a note to let you know that I've just added the patch titled

ata: fixes kernel crash while tracing ata_eh_link_autopsy event

to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
ata-fixes-kernel-crash-while-tracing-ata_eh_link_autopsy-event.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Rameshwar Prasad Sahu <[email protected]>
Date: Thu, 2 Nov 2017 16:31:07 +0530
Subject: ata: fixes kernel crash while tracing ata_eh_link_autopsy event

From: Rameshwar Prasad Sahu <[email protected]>

commit f1601113ddc0339a745e702f4fb1ca37d4875e65 upstream.

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.

---
 drivers/ata/libata-eh.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

@@ -2329,8 +2329,8 @@ static void ata_eh_link_autopsy(struct a
 		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");
 }
 

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/ata-fixes-kernel-crash-while-tracing-ata_eh_link_autopsy-event.patch