4.14-stable review patch. If anyone has any objections, please let me know.
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From: Haiyang Zhang haiyangz@microsoft.com
[ Upstream commit 11b2b653102571ac791885324371d9a1a17b900e ]
The max should be 31 MB on host with NVSP version > 2.
On legacy hosts (NVSP version <=2) only 15 MB receive buffer is allowed, otherwise the buffer request will be rejected by the host, resulting vNIC not coming up.
The NVSP version is only available after negotiation. So, we add the limit checking for legacy hosts in netvsc_init_buf().
Fixes: 5023a6db73196 ("netvsc: increase default receive buffer size") Signed-off-by: Haiyang Zhang haiyangz@microsoft.com Signed-off-by: Stephen Hemminger sthemmin@microsoft.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/hyperv/hyperv_net.h | 6 ++++-- drivers/net/hyperv/netvsc.c | 5 +++++ 2 files changed, 9 insertions(+), 2 deletions(-)
--- a/drivers/net/hyperv/hyperv_net.h +++ b/drivers/net/hyperv/hyperv_net.h @@ -635,9 +635,11 @@ struct nvsp_message { #define NETVSC_MTU 65535 #define NETVSC_MTU_MIN ETH_MIN_MTU
-#define NETVSC_RECEIVE_BUFFER_SIZE (1024*1024*16) /* 16MB */ -#define NETVSC_RECEIVE_BUFFER_SIZE_LEGACY (1024*1024*15) /* 15MB */ +/* Max buffer sizes allowed by a host */ +#define NETVSC_RECEIVE_BUFFER_SIZE (1024 * 1024 * 31) /* 31MB */ +#define NETVSC_RECEIVE_BUFFER_SIZE_LEGACY (1024 * 1024 * 15) /* 15MB */ #define NETVSC_SEND_BUFFER_SIZE (1024 * 1024 * 15) /* 15MB */ + #define NETVSC_INVALID_INDEX -1
#define NETVSC_SEND_SECTION_SIZE 6144 --- a/drivers/net/hyperv/netvsc.c +++ b/drivers/net/hyperv/netvsc.c @@ -262,6 +262,11 @@ static int netvsc_init_buf(struct hv_dev buf_size = device_info->recv_sections * device_info->recv_section_size; buf_size = roundup(buf_size, PAGE_SIZE);
+ /* Legacy hosts only allow smaller receive buffer */ + if (net_device->nvsp_version <= NVSP_PROTOCOL_VERSION_2) + buf_size = min_t(unsigned int, buf_size, + NETVSC_RECEIVE_BUFFER_SIZE_LEGACY); + net_device->recv_buf = vzalloc(buf_size); if (!net_device->recv_buf) { netdev_err(ndev,