kernel/linux
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ synced 2026-10-24 19:10:26 +00:00
Code Issues Releases Packages Activity
linux/drivers/net/hyperv
History
Michael Kelley 4d53556d87 hv_netvsc: Calculate correct ring size when PAGE_SIZE is not 4 Kbytes 
commit 6941f67ad3 upstream.

Current code in netvsc_drv_init() incorrectly assumes that PAGE_SIZE
is 4 Kbytes, which is wrong on ARM64 with 16K or 64K page size. As a
result, the default VMBus ring buffer size on ARM64 with 64K page size
is 8 Mbytes instead of the expected 512 Kbytes. While this doesn't break
anything, a typical VM with 8 vCPUs and 8 netvsc channels wastes 120
Mbytes (8 channels * 2 ring buffers/channel * 7.5 Mbytes/ring buffer).

Unfortunately, the module parameter specifying the ring buffer size
is in units of 4 Kbyte pages. Ideally, it should be in units that
are independent of PAGE_SIZE, but backwards compatibility prevents
changing that now.

Fix this by having netvsc_drv_init() hardcode 4096 instead of using
PAGE_SIZE when calculating the ring buffer size in bytes. Also
use the VMBUS_RING_SIZE macro to ensure proper alignment when running
with page size larger than 4K.

Cc: <stable@vger.kernel.org> # 5.15.x
Fixes: 7aff79e297 ("Drivers: hv: Enable Hyper-V code to be built on ARM64")
Signed-off-by: Michael Kelley <mhklinux@outlook.com>
Link: https://lore.kernel.org/r/20240122162028.348885-1-mhklinux@outlook.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
History 2024-01-31 16:19:06 -08:00
..
hyperv_net.h eth: add missing xdp.h includes in drivers 2023-08-03 08:38:07 -07:00
Kconfig hv_netvsc: rndis_filter needs to select NLS 2023-12-13 18:45:04 +01:00
Makefile hv_netvsc: Add XDP support 2020-01-25 10:43:19 +01:00
netvsc.c hv_netvsc: Remove second mapping of send and recv buffers 2023-04-17 19:19:04 +00:00
netvsc_bpf.c hv_netvsc: Add support for XDP_REDIRECT 2022-04-11 18:25:47 -07:00
netvsc_drv.c hv_netvsc: Calculate correct ring size when PAGE_SIZE is not 4 Kbytes 2024-01-31 16:19:06 -08:00
netvsc_trace.c hv_netvsc: add trace points 2018-03-17 20:10:27 -04:00
netvsc_trace.h hv_netvsc: add trace points 2018-03-17 20:10:27 -04:00
rndis_filter.c hv_netvsc: Allocate rx indirection table size dynamically 2023-06-07 09:46:49 +01:00