Patch "pmem: return EIO on read_pmem() failure" has been added to the 4.9-stable tree

[<gregkh@linuxfoundation.org>]

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

    pmem: return EIO on read_pmem() failure

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:
     pmem-return-eio-on-read_pmem-failure.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 <stable@vger.kernel.org> know about it.


>From foo@baz Mon Jul  3 13:33:55 CEST 2017
From: Stefan Hajnoczi <stefanha@redhat.com>
Date: Thu, 5 Jan 2017 10:05:46 +0000
Subject: pmem: return EIO on read_pmem() failure

From: Stefan Hajnoczi <stefanha@redhat.com>


[ Upstream commit d47d1d27fd6206c18806440f6ebddf51a806be4f ]

The read_pmem() function uses memcpy_mcsafe() on x86 where an EFAULT
error code indicates a failed read.  Block I/O should use EIO to
indicate failure.  Other pmem code paths (like bad blocks) already use
EIO so let's be consistent.

This fixes compatibility with consumers like btrfs that try to parse the
specific error code rather than treat all errors the same.

Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/nvdimm/pmem.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

--- a/drivers/nvdimm/pmem.c
+++ b/drivers/nvdimm/pmem.c
@@ -87,7 +87,9 @@ static int read_pmem(struct page *page,
 
 	rc = memcpy_from_pmem(mem + off, pmem_addr, len);
 	kunmap_atomic(mem);
-	return rc;
+	if (rc)
+		return -EIO;
+	return 0;
 }
 
 static int pmem_do_bvec(struct pmem_device *pmem, struct page *page,


Patches currently in stable-queue which might be from stefanha@redhat.com are

queue-4.9/pmem-return-eio-on-read_pmem-failure.patch