shinys000114/linux
1
0
Fork 0
mirror of https://github.com/hardkernel/linux.git synced 2026-06-06 10:58:48 +09:00
Code Issues Packages Projects Releases Wiki Activity

virtio_net: fix PAGE_SIZE > 64k

Browse Source 
[ Upstream commit d0fa28f000 ]

I don't have any guests with PAGE_SIZE > 64k but the
code seems to be clearly broken in that case
as PAGE_SIZE / MERGEABLE_BUFFER_ALIGN will need
more than 8 bit and so the code in mergeable_ctx_to_buf_address
does not give us the actual true size.

Cc: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Michael S. Tsirkin
2017-01-23 21:37:52 +02:00
committed by Greg Kroah-Hartman
parent a6c3e01bf3
commit 7fdc81f6e1
1 changed files with 9 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

10
drivers/net/virtio_net.c
View File

@@ -47,8 +47,16 @@ module_param(gso, bool, 0444);
*/
DECLARE_EWMA(pkt_len, 1, 64)
/* With mergeable buffers we align buffer address and use the low bits to
* encode its true size. Buffer size is up to 1 page so we need to align to
* square root of page size to ensure we reserve enough bits to encode the true
* size.
*/
#define MERGEABLE_BUFFER_MIN_ALIGN_SHIFT ((PAGE_SHIFT + 1) / 2)
/* Minimum alignment for mergeable packet buffers. */
#define MERGEABLE_BUFFER_ALIGN max(L1_CACHE_BYTES, 256)
#define MERGEABLE_BUFFER_ALIGN max(L1_CACHE_BYTES, \
1 << MERGEABLE_BUFFER_MIN_ALIGN_SHIFT)
#define VIRTNET_DRIVER_VERSION "1.0.0"