Patch "lightnvm: pblk: protect line bitmap while submitting meta io" has been added to the 4.14-stable tree

Patch "lightnvm: pblk: protect line bitmap while submitting meta io" has been added to the 4.14-stable tree

[gregkh]

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

    lightnvm: pblk: protect line bitmap while submitting meta io

to the 4.14-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:
     lightnvm-pblk-protect-line-bitmap-while-submitting-meta-io.patch
and it can be found in the queue-4.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From foo@baz Mon Dec 18 13:29:00 CET 2017
From: Rakesh Pandit <rakesh@tuxera.com>
Date: Fri, 13 Oct 2017 14:45:56 +0200
Subject: lightnvm: pblk: protect line bitmap while submitting meta io

From: Rakesh Pandit <rakesh@tuxera.com>


[ Upstream commit e57903fd972a398b7140d0bc055714e13a0e58c5 ]

It seems pblk_dealloc_page would race against pblk_alloc_pages for
line bitmap for sector allocation.The chances are very low but might
as well protect the bitmap properly.

Signed-off-by: Rakesh Pandit <rakesh@tuxera.com>
Reviewed-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/lightnvm/pblk-core.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/drivers/lightnvm/pblk-core.c
+++ b/drivers/lightnvm/pblk-core.c
@@ -486,12 +486,14 @@ void pblk_dealloc_page(struct pblk *pblk
 	u64 addr;
 	int i;
 
+	spin_lock(&line->lock);
 	addr = find_next_zero_bit(line->map_bitmap,
 					pblk->lm.sec_per_line, line->cur_sec);
 	line->cur_sec = addr - nr_secs;
 
 	for (i = 0; i < nr_secs; i++, line->cur_sec--)
 		WARN_ON(!test_and_clear_bit(line->cur_sec, line->map_bitmap));
+	spin_unlock(&line->lock);
 }
 
 u64 __pblk_alloc_page(struct pblk *pblk, struct pblk_line *line, int nr_secs)


Patches currently in stable-queue which might be from rakesh@tuxera.com are

queue-4.14/lightnvm-pblk-protect-line-bitmap-while-submitting-meta-io.patch
queue-4.14/lightnvm-pblk-fix-changing-gc-group-list-for-a-line.patch