Patch "pstore/ram: Use memcpy_toio instead of memcpy" has been added to the 4.4-stable tree

Patch "pstore/ram: Use memcpy_toio instead of memcpy" has been added to the 4.4-stable tree

[gregkh]

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

    pstore/ram: Use memcpy_toio instead of memcpy

to the 4.4-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:
     pstore-ram-use-memcpy_toio-instead-of-memcpy.patch
and it can be found in the queue-4.4 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 7e75678d23167c2527e655658a8ef36a36c8b4d9 Mon Sep 17 00:00:00 2001
From: Furquan Shaikh <furquan@google.com>
Date: Mon, 15 Feb 2016 09:19:48 +0100
Subject: pstore/ram: Use memcpy_toio instead of memcpy

From: Furquan Shaikh <furquan@google.com>

commit 7e75678d23167c2527e655658a8ef36a36c8b4d9 upstream.

persistent_ram_update uses vmap / iomap based on whether the buffer is in
memory region or reserved region. However, both map it as non-cacheable
memory. For armv8 specifically, non-cacheable mapping requests use a
memory type that has to be accessed aligned to the request size. memcpy()
doesn't guarantee that.

Signed-off-by: Furquan Shaikh <furquan@google.com>
Signed-off-by: Enric Balletbo Serra <enric.balletbo@collabora.com>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Olof Johansson <olofj@chromium.org>
Tested-by: Furquan Shaikh <furquan@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 fs/pstore/ram_core.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/fs/pstore/ram_core.c
+++ b/fs/pstore/ram_core.c
@@ -263,7 +263,7 @@ static void notrace persistent_ram_updat
 	const void *s, unsigned int start, unsigned int count)
 {
 	struct persistent_ram_buffer *buffer = prz->buffer;
-	memcpy(buffer->data + start, s, count);
+	memcpy_toio(buffer->data + start, s, count);
 	persistent_ram_update_ecc(prz, start, count);
 }
 


Patches currently in stable-queue which might be from furquan@google.com are

queue-4.4/pstore-ram-use-memcpy_toio-instead-of-memcpy.patch