Patch "pmem: add proper fencing to pmem_rw_page()" has been added to the 4.2-stable tree

Patch "pmem: add proper fencing to pmem_rw_page()" has been added to the 4.2-stable tree

[gregkh]

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

    pmem: add proper fencing to pmem_rw_page()

to the 4.2-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:
     pmem-add-proper-fencing-to-pmem_rw_page.patch
and it can be found in the queue-4.2 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 ba8fe0f85e15d047686caf8a42463b592c63c98c Mon Sep 17 00:00:00 2001
From: Ross Zwisler <ross.zwisler@linux.intel.com>
Date: Wed, 16 Sep 2015 14:52:21 -0600
Subject: pmem: add proper fencing to pmem_rw_page()

From: Ross Zwisler <ross.zwisler@linux.intel.com>

commit ba8fe0f85e15d047686caf8a42463b592c63c98c upstream.

pmem_rw_page() needs to call wmb_pmem() on writes to make sure that the
newly written data is durable.  This flow was added to pmem_rw_bytes()
and pmem_make_request() with this commit:

commit 61031952f4c8 ("arch, x86: pmem api for ensuring durability of
	persistent memory updates")

...the pmem_rw_page() path was missed.

Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/nvdimm/pmem.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/drivers/nvdimm/pmem.c
+++ b/drivers/nvdimm/pmem.c
@@ -86,6 +86,8 @@ static int pmem_rw_page(struct block_dev
 	struct pmem_device *pmem = bdev->bd_disk->private_data;
 
 	pmem_do_bvec(pmem, page, PAGE_CACHE_SIZE, 0, rw, sector);
+	if (rw & WRITE)
+		wmb_pmem();
 	page_endio(page, rw & WRITE, 0);
 
 	return 0;


Patches currently in stable-queue which might be from ross.zwisler@linux.intel.com are

queue-4.2/pmem-add-proper-fencing-to-pmem_rw_page.patch