From: Keith Busch <keith.busch@intel.com>
Date: Mon, 3 Mar 2014 23:39:13 +0000 (-0700)
Subject: NVMe: IOCTL path RCU protect queue access
X-Git-Tag: v3.15-rc1~21^2~8
X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=4f5099af4f3d5f999d8ab7784472d93e810e3912;p=pandora-kernel.git

NVMe: IOCTL path RCU protect queue access

This adds rcu protected access to a queue in the nvme IOCTL path
to fix potential races between a surprise removal and queue usage in
nvme_submit_sync_cmd. The fix holds the rcu_read_lock() here to prevent
the nvme_queue from freeing while this path is executing so it can't
sleep, and so this path will no longer wait for a available command
id should they all be in use at the time a passthrough IOCTL request
is received.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
---

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