* [PATCH net-next 1/3] sfc: use padding to fix alignment in loopback test
2023-06-22 10:18 [PATCH net-next 0/3] sfc: fix unaligned access in loopback selftests edward.cree
@ 2023-06-22 10:18 ` edward.cree
2023-06-22 11:38 ` Arnd Bergmann
2023-06-22 10:18 ` [PATCH net-next 2/3] sfc: siena: " edward.cree
2023-06-22 10:18 ` [PATCH net-next 3/3] sfc: falcon: " edward.cree
2 siblings, 1 reply; 7+ messages in thread
From: edward.cree @ 2023-06-22 10:18 UTC (permalink / raw)
To: linux-net-drivers, davem, kuba, edumazet, pabeni
Cc: arnd, Edward Cree, netdev, habetsm.xilinx
From: Edward Cree <ecree.xilinx@gmail.com>
Add two bytes of padding to the start of struct efx_loopback_payload,
which are not sent on the wire. This ensures the 'ip' member is
4-byte aligned, preventing the following W=1 warning:
net/ethernet/sfc/selftest.c:46:15: error: field ip within 'struct efx_loopback_payload' is less aligned than 'struct iphdr' and is usually due to 'struct efx_loopback_payload' being packed, which can lead to unaligned accesses [-Werror,-Wunaligned-access]
struct iphdr ip;
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Edward Cree <ecree.xilinx@gmail.com>
---
drivers/net/ethernet/sfc/selftest.c | 45 +++++++++++++++++------------
1 file changed, 27 insertions(+), 18 deletions(-)
diff --git a/drivers/net/ethernet/sfc/selftest.c b/drivers/net/ethernet/sfc/selftest.c
index 3c5227afd497..74b42efe7267 100644
--- a/drivers/net/ethernet/sfc/selftest.c
+++ b/drivers/net/ethernet/sfc/selftest.c
@@ -42,12 +42,16 @@
* Falcon only performs RSS on TCP/UDP packets.
*/
struct efx_loopback_payload {
+ char pad[2]; /* Ensures ip is 4-byte aligned */
struct ethhdr header;
struct iphdr ip;
struct udphdr udp;
__be16 iteration;
char msg[64];
} __packed;
+#define EFX_LOOPBACK_PAYLOAD_LEN (sizeof(struct efx_loopback_payload) - \
+ offsetof(struct efx_loopback_payload, \
+ header))
/* Loopback test source MAC address */
static const u8 payload_source[ETH_ALEN] __aligned(2) = {
@@ -282,7 +286,7 @@ void efx_loopback_rx_packet(struct efx_nic *efx,
const char *buf_ptr, int pkt_len)
{
struct efx_loopback_state *state = efx->loopback_selftest;
- struct efx_loopback_payload *received;
+ struct efx_loopback_payload received;
struct efx_loopback_payload *payload;
BUG_ON(!buf_ptr);
@@ -293,13 +297,14 @@ void efx_loopback_rx_packet(struct efx_nic *efx,
payload = &state->payload;
- received = (struct efx_loopback_payload *) buf_ptr;
- received->ip.saddr = payload->ip.saddr;
+ memcpy(&received.header, buf_ptr,
+ min_t(int, pkt_len, EFX_LOOPBACK_PAYLOAD_LEN));
+ received.ip.saddr = payload->ip.saddr;
if (state->offload_csum)
- received->ip.check = payload->ip.check;
+ received.ip.check = payload->ip.check;
/* Check that header exists */
- if (pkt_len < sizeof(received->header)) {
+ if (pkt_len < sizeof(received.header)) {
netif_err(efx, drv, efx->net_dev,
"saw runt RX packet (length %d) in %s loopback "
"test\n", pkt_len, LOOPBACK_MODE(efx));
@@ -307,7 +312,7 @@ void efx_loopback_rx_packet(struct efx_nic *efx,
}
/* Check that the ethernet header exists */
- if (memcmp(&received->header, &payload->header, ETH_HLEN) != 0) {
+ if (memcmp(&received.header, &payload->header, ETH_HLEN) != 0) {
netif_err(efx, drv, efx->net_dev,
"saw non-loopback RX packet in %s loopback test\n",
LOOPBACK_MODE(efx));
@@ -315,16 +320,16 @@ void efx_loopback_rx_packet(struct efx_nic *efx,
}
/* Check packet length */
- if (pkt_len != sizeof(*payload)) {
+ if (pkt_len != EFX_LOOPBACK_PAYLOAD_LEN) {
netif_err(efx, drv, efx->net_dev,
"saw incorrect RX packet length %d (wanted %d) in "
- "%s loopback test\n", pkt_len, (int)sizeof(*payload),
- LOOPBACK_MODE(efx));
+ "%s loopback test\n", pkt_len,
+ (int)EFX_LOOPBACK_PAYLOAD_LEN, LOOPBACK_MODE(efx));
goto err;
}
/* Check that IP header matches */
- if (memcmp(&received->ip, &payload->ip, sizeof(payload->ip)) != 0) {
+ if (memcmp(&received.ip, &payload->ip, sizeof(payload->ip)) != 0) {
netif_err(efx, drv, efx->net_dev,
"saw corrupted IP header in %s loopback test\n",
LOOPBACK_MODE(efx));
@@ -332,7 +337,7 @@ void efx_loopback_rx_packet(struct efx_nic *efx,
}
/* Check that msg and padding matches */
- if (memcmp(&received->msg, &payload->msg, sizeof(received->msg)) != 0) {
+ if (memcmp(&received.msg, &payload->msg, sizeof(received.msg)) != 0) {
netif_err(efx, drv, efx->net_dev,
"saw corrupted RX packet in %s loopback test\n",
LOOPBACK_MODE(efx));
@@ -340,10 +345,10 @@ void efx_loopback_rx_packet(struct efx_nic *efx,
}
/* Check that iteration matches */
- if (received->iteration != payload->iteration) {
+ if (received.iteration != payload->iteration) {
netif_err(efx, drv, efx->net_dev,
"saw RX packet from iteration %d (wanted %d) in "
- "%s loopback test\n", ntohs(received->iteration),
+ "%s loopback test\n", ntohs(received.iteration),
ntohs(payload->iteration), LOOPBACK_MODE(efx));
goto err;
}
@@ -363,7 +368,8 @@ void efx_loopback_rx_packet(struct efx_nic *efx,
buf_ptr, pkt_len, 0);
netif_err(efx, drv, efx->net_dev, "expected packet:\n");
print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 0x10, 1,
- &state->payload, sizeof(state->payload), 0);
+ &state->payload.header, EFX_LOOPBACK_PAYLOAD_LEN,
+ 0);
}
#endif
atomic_inc(&state->rx_bad);
@@ -385,14 +391,15 @@ static void efx_iterate_state(struct efx_nic *efx)
payload->ip.daddr = htonl(INADDR_LOOPBACK);
payload->ip.ihl = 5;
payload->ip.check = (__force __sum16) htons(0xdead);
- payload->ip.tot_len = htons(sizeof(*payload) - sizeof(struct ethhdr));
+ payload->ip.tot_len = htons(sizeof(*payload) -
+ offsetof(struct efx_loopback_payload, ip));
payload->ip.version = IPVERSION;
payload->ip.protocol = IPPROTO_UDP;
/* Initialise udp header */
payload->udp.source = 0;
- payload->udp.len = htons(sizeof(*payload) - sizeof(struct ethhdr) -
- sizeof(struct iphdr));
+ payload->udp.len = htons(sizeof(*payload) -
+ offsetof(struct efx_loopback_payload, udp));
payload->udp.check = 0; /* checksum ignored */
/* Fill out payload */
@@ -418,7 +425,7 @@ static int efx_begin_loopback(struct efx_tx_queue *tx_queue)
for (i = 0; i < state->packet_count; i++) {
/* Allocate an skb, holding an extra reference for
* transmit completion counting */
- skb = alloc_skb(sizeof(state->payload), GFP_KERNEL);
+ skb = alloc_skb(EFX_LOOPBACK_PAYLOAD_LEN, GFP_KERNEL);
if (!skb)
return -ENOMEM;
state->skbs[i] = skb;
@@ -429,6 +436,8 @@ static int efx_begin_loopback(struct efx_tx_queue *tx_queue)
payload = skb_put(skb, sizeof(state->payload));
memcpy(payload, &state->payload, sizeof(state->payload));
payload->ip.saddr = htonl(INADDR_LOOPBACK | (i << 2));
+ /* Strip off the leading padding */
+ skb_pull(skb, offsetof(struct efx_loopback_payload, header));
/* Ensure everything we've written is visible to the
* interrupt handler. */
^ permalink raw reply related [flat|nested] 7+ messages in thread* Re: [PATCH net-next 1/3] sfc: use padding to fix alignment in loopback test
2023-06-22 10:18 ` [PATCH net-next 1/3] sfc: use padding to fix alignment in loopback test edward.cree
@ 2023-06-22 11:38 ` Arnd Bergmann
2023-06-22 12:02 ` Edward Cree
0 siblings, 1 reply; 7+ messages in thread
From: Arnd Bergmann @ 2023-06-22 11:38 UTC (permalink / raw)
To: edward.cree, linux-net-drivers, David S . Miller, Jakub Kicinski,
Eric Dumazet, Paolo Abeni
Cc: Edward Cree, Netdev, Martin Habets
On Thu, Jun 22, 2023, at 12:18, edward.cree@amd.com wrote:
> drivers/net/ethernet/sfc/selftest.c | 45 +++++++++++++++++------------
> 1 file changed, 27 insertions(+), 18 deletions(-)
>
> diff --git a/drivers/net/ethernet/sfc/selftest.c
> b/drivers/net/ethernet/sfc/selftest.c
> index 3c5227afd497..74b42efe7267 100644
> --- a/drivers/net/ethernet/sfc/selftest.c
> +++ b/drivers/net/ethernet/sfc/selftest.c
> @@ -42,12 +42,16 @@
> * Falcon only performs RSS on TCP/UDP packets.
> */
> struct efx_loopback_payload {
> + char pad[2]; /* Ensures ip is 4-byte aligned */
> struct ethhdr header;
> struct iphdr ip;
> struct udphdr udp;
> __be16 iteration;
> char msg[64];
> } __packed;
There should probably be an extra __aligned(4) after the __packed,
so that the compiler knows the start of the structure is aligned,
otherwise (depending on the architecture and compiler), any access
to a member can still turn into multiple single-byte accesses.
I would also expect to still see a warning without that extra
attribute. Aside from this, the patch looks good to me.
Arnd
^ permalink raw reply [flat|nested] 7+ messages in thread* Re: [PATCH net-next 1/3] sfc: use padding to fix alignment in loopback test
2023-06-22 11:38 ` Arnd Bergmann
@ 2023-06-22 12:02 ` Edward Cree
2023-06-22 12:19 ` Arnd Bergmann
0 siblings, 1 reply; 7+ messages in thread
From: Edward Cree @ 2023-06-22 12:02 UTC (permalink / raw)
To: Arnd Bergmann, edward.cree, linux-net-drivers, David S . Miller,
Jakub Kicinski, Eric Dumazet, Paolo Abeni
Cc: Netdev, Martin Habets
On 22/06/2023 12:38, Arnd Bergmann wrote:
> On Thu, Jun 22, 2023, at 12:18, edward.cree@amd.com wrote:
>> drivers/net/ethernet/sfc/selftest.c | 45 +++++++++++++++++------------
>> 1 file changed, 27 insertions(+), 18 deletions(-)
>>
>> diff --git a/drivers/net/ethernet/sfc/selftest.c
>> b/drivers/net/ethernet/sfc/selftest.c
>> index 3c5227afd497..74b42efe7267 100644
>> --- a/drivers/net/ethernet/sfc/selftest.c
>> +++ b/drivers/net/ethernet/sfc/selftest.c
>> @@ -42,12 +42,16 @@
>> * Falcon only performs RSS on TCP/UDP packets.
>> */
>> struct efx_loopback_payload {
>> + char pad[2]; /* Ensures ip is 4-byte aligned */
>> struct ethhdr header;
>> struct iphdr ip;
>> struct udphdr udp;
>> __be16 iteration;
>> char msg[64];
>> } __packed;
>
> There should probably be an extra __aligned(4) after the __packed,
> so that the compiler knows the start of the structure is aligned,
> otherwise (depending on the architecture and compiler), any access
> to a member can still turn into multiple single-byte accesses.
Ok, will add that in v2.
> I would also expect to still see a warning without that extra
> attribute. Aside from this, the patch looks good to me.
My compiler (gcc 8.3.1) doesn't reproduce the original warning, so
I'm flying slightly blind here :( If you could build-test this on
your setup with/without the __aligned(4), I'd be very grateful.
-ed
^ permalink raw reply [flat|nested] 7+ messages in thread* Re: [PATCH net-next 1/3] sfc: use padding to fix alignment in loopback test
2023-06-22 12:02 ` Edward Cree
@ 2023-06-22 12:19 ` Arnd Bergmann
0 siblings, 0 replies; 7+ messages in thread
From: Arnd Bergmann @ 2023-06-22 12:19 UTC (permalink / raw)
To: Edward Cree, edward.cree, linux-net-drivers, David S . Miller,
Jakub Kicinski, Eric Dumazet, Paolo Abeni
Cc: Netdev, Martin Habets
On Thu, Jun 22, 2023, at 14:02, Edward Cree wrote:
> On 22/06/2023 12:38, Arnd Bergmann wrote:
>> On Thu, Jun 22, 2023, at 12:18, edward.cree@amd.com wrote:
>>
>> There should probably be an extra __aligned(4) after the __packed,
>> so that the compiler knows the start of the structure is aligned,
>> otherwise (depending on the architecture and compiler), any access
>> to a member can still turn into multiple single-byte accesses.
>
> Ok, will add that in v2.
>
>> I would also expect to still see a warning without that extra
>> attribute. Aside from this, the patch looks good to me.
> My compiler (gcc 8.3.1) doesn't reproduce the original warning, so
> I'm flying slightly blind here :( If you could build-test this on
> your setup with/without the __aligned(4), I'd be very grateful.
I can confirm that your patch addresses the warning for me
with any version of clang I have installed, and that the __aligned(4)
is not needed for the warning, though it is still a good idea for
code generation.
Arnd
^ permalink raw reply [flat|nested] 7+ messages in thread
* [PATCH net-next 2/3] sfc: siena: use padding to fix alignment in loopback test
2023-06-22 10:18 [PATCH net-next 0/3] sfc: fix unaligned access in loopback selftests edward.cree
2023-06-22 10:18 ` [PATCH net-next 1/3] sfc: use padding to fix alignment in loopback test edward.cree
@ 2023-06-22 10:18 ` edward.cree
2023-06-22 10:18 ` [PATCH net-next 3/3] sfc: falcon: " edward.cree
2 siblings, 0 replies; 7+ messages in thread
From: edward.cree @ 2023-06-22 10:18 UTC (permalink / raw)
To: linux-net-drivers, davem, kuba, edumazet, pabeni
Cc: arnd, Edward Cree, netdev, habetsm.xilinx
From: Edward Cree <ecree.xilinx@gmail.com>
Add two bytes of padding to the start of struct efx_loopback_payload,
which are not sent on the wire. This ensures the 'ip' member is
4-byte aligned, preventing the following W=1 warning:
net/ethernet/sfc/siena/selftest.c:46:15: error: field ip within 'struct efx_loopback_payload' is less aligned than 'struct iphdr' and is usually due to 'struct efx_loopback_payload' being packed, which can lead to unaligned accesses [-Werror,-Wunaligned-access]
struct iphdr ip;
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Edward Cree <ecree.xilinx@gmail.com>
---
drivers/net/ethernet/sfc/siena/selftest.c | 45 ++++++++++++++---------
1 file changed, 27 insertions(+), 18 deletions(-)
diff --git a/drivers/net/ethernet/sfc/siena/selftest.c b/drivers/net/ethernet/sfc/siena/selftest.c
index 07715a3d6bea..c65c62dc642e 100644
--- a/drivers/net/ethernet/sfc/siena/selftest.c
+++ b/drivers/net/ethernet/sfc/siena/selftest.c
@@ -42,12 +42,16 @@
* Falcon only performs RSS on TCP/UDP packets.
*/
struct efx_loopback_payload {
+ char pad[2]; /* Ensures ip is 4-byte aligned */
struct ethhdr header;
struct iphdr ip;
struct udphdr udp;
__be16 iteration;
char msg[64];
} __packed;
+#define EFX_LOOPBACK_PAYLOAD_LEN (sizeof(struct efx_loopback_payload) - \
+ offsetof(struct efx_loopback_payload, \
+ header))
/* Loopback test source MAC address */
static const u8 payload_source[ETH_ALEN] __aligned(2) = {
@@ -282,7 +286,7 @@ void efx_siena_loopback_rx_packet(struct efx_nic *efx,
const char *buf_ptr, int pkt_len)
{
struct efx_loopback_state *state = efx->loopback_selftest;
- struct efx_loopback_payload *received;
+ struct efx_loopback_payload received;
struct efx_loopback_payload *payload;
BUG_ON(!buf_ptr);
@@ -293,13 +297,14 @@ void efx_siena_loopback_rx_packet(struct efx_nic *efx,
payload = &state->payload;
- received = (struct efx_loopback_payload *) buf_ptr;
- received->ip.saddr = payload->ip.saddr;
+ memcpy(&received.header, buf_ptr,
+ min_t(int, pkt_len, EFX_LOOPBACK_PAYLOAD_LEN));
+ received.ip.saddr = payload->ip.saddr;
if (state->offload_csum)
- received->ip.check = payload->ip.check;
+ received.ip.check = payload->ip.check;
/* Check that header exists */
- if (pkt_len < sizeof(received->header)) {
+ if (pkt_len < sizeof(received.header)) {
netif_err(efx, drv, efx->net_dev,
"saw runt RX packet (length %d) in %s loopback "
"test\n", pkt_len, LOOPBACK_MODE(efx));
@@ -307,7 +312,7 @@ void efx_siena_loopback_rx_packet(struct efx_nic *efx,
}
/* Check that the ethernet header exists */
- if (memcmp(&received->header, &payload->header, ETH_HLEN) != 0) {
+ if (memcmp(&received.header, &payload->header, ETH_HLEN) != 0) {
netif_err(efx, drv, efx->net_dev,
"saw non-loopback RX packet in %s loopback test\n",
LOOPBACK_MODE(efx));
@@ -315,16 +320,16 @@ void efx_siena_loopback_rx_packet(struct efx_nic *efx,
}
/* Check packet length */
- if (pkt_len != sizeof(*payload)) {
+ if (pkt_len != EFX_LOOPBACK_PAYLOAD_LEN) {
netif_err(efx, drv, efx->net_dev,
"saw incorrect RX packet length %d (wanted %d) in "
- "%s loopback test\n", pkt_len, (int)sizeof(*payload),
- LOOPBACK_MODE(efx));
+ "%s loopback test\n", pkt_len,
+ (int)EFX_LOOPBACK_PAYLOAD_LEN, LOOPBACK_MODE(efx));
goto err;
}
/* Check that IP header matches */
- if (memcmp(&received->ip, &payload->ip, sizeof(payload->ip)) != 0) {
+ if (memcmp(&received.ip, &payload->ip, sizeof(payload->ip)) != 0) {
netif_err(efx, drv, efx->net_dev,
"saw corrupted IP header in %s loopback test\n",
LOOPBACK_MODE(efx));
@@ -332,7 +337,7 @@ void efx_siena_loopback_rx_packet(struct efx_nic *efx,
}
/* Check that msg and padding matches */
- if (memcmp(&received->msg, &payload->msg, sizeof(received->msg)) != 0) {
+ if (memcmp(&received.msg, &payload->msg, sizeof(received.msg)) != 0) {
netif_err(efx, drv, efx->net_dev,
"saw corrupted RX packet in %s loopback test\n",
LOOPBACK_MODE(efx));
@@ -340,10 +345,10 @@ void efx_siena_loopback_rx_packet(struct efx_nic *efx,
}
/* Check that iteration matches */
- if (received->iteration != payload->iteration) {
+ if (received.iteration != payload->iteration) {
netif_err(efx, drv, efx->net_dev,
"saw RX packet from iteration %d (wanted %d) in "
- "%s loopback test\n", ntohs(received->iteration),
+ "%s loopback test\n", ntohs(received.iteration),
ntohs(payload->iteration), LOOPBACK_MODE(efx));
goto err;
}
@@ -363,7 +368,8 @@ void efx_siena_loopback_rx_packet(struct efx_nic *efx,
buf_ptr, pkt_len, 0);
netif_err(efx, drv, efx->net_dev, "expected packet:\n");
print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 0x10, 1,
- &state->payload, sizeof(state->payload), 0);
+ &state->payload.header, EFX_LOOPBACK_PAYLOAD_LEN,
+ 0);
}
#endif
atomic_inc(&state->rx_bad);
@@ -385,14 +391,15 @@ static void efx_iterate_state(struct efx_nic *efx)
payload->ip.daddr = htonl(INADDR_LOOPBACK);
payload->ip.ihl = 5;
payload->ip.check = (__force __sum16) htons(0xdead);
- payload->ip.tot_len = htons(sizeof(*payload) - sizeof(struct ethhdr));
+ payload->ip.tot_len = htons(sizeof(*payload) -
+ offsetof(struct efx_loopback_payload, ip));
payload->ip.version = IPVERSION;
payload->ip.protocol = IPPROTO_UDP;
/* Initialise udp header */
payload->udp.source = 0;
- payload->udp.len = htons(sizeof(*payload) - sizeof(struct ethhdr) -
- sizeof(struct iphdr));
+ payload->udp.len = htons(sizeof(*payload) -
+ offsetof(struct efx_loopback_payload, udp));
payload->udp.check = 0; /* checksum ignored */
/* Fill out payload */
@@ -418,7 +425,7 @@ static int efx_begin_loopback(struct efx_tx_queue *tx_queue)
for (i = 0; i < state->packet_count; i++) {
/* Allocate an skb, holding an extra reference for
* transmit completion counting */
- skb = alloc_skb(sizeof(state->payload), GFP_KERNEL);
+ skb = alloc_skb(EFX_LOOPBACK_PAYLOAD_LEN, GFP_KERNEL);
if (!skb)
return -ENOMEM;
state->skbs[i] = skb;
@@ -429,6 +436,8 @@ static int efx_begin_loopback(struct efx_tx_queue *tx_queue)
payload = skb_put(skb, sizeof(state->payload));
memcpy(payload, &state->payload, sizeof(state->payload));
payload->ip.saddr = htonl(INADDR_LOOPBACK | (i << 2));
+ /* Strip off the leading padding */
+ skb_pull(skb, offsetof(struct efx_loopback_payload, header));
/* Ensure everything we've written is visible to the
* interrupt handler. */
^ permalink raw reply related [flat|nested] 7+ messages in thread* [PATCH net-next 3/3] sfc: falcon: use padding to fix alignment in loopback test
2023-06-22 10:18 [PATCH net-next 0/3] sfc: fix unaligned access in loopback selftests edward.cree
2023-06-22 10:18 ` [PATCH net-next 1/3] sfc: use padding to fix alignment in loopback test edward.cree
2023-06-22 10:18 ` [PATCH net-next 2/3] sfc: siena: " edward.cree
@ 2023-06-22 10:18 ` edward.cree
2 siblings, 0 replies; 7+ messages in thread
From: edward.cree @ 2023-06-22 10:18 UTC (permalink / raw)
To: linux-net-drivers, davem, kuba, edumazet, pabeni
Cc: arnd, Edward Cree, netdev, habetsm.xilinx
From: Edward Cree <ecree.xilinx@gmail.com>
Add two bytes of padding to the start of struct ef4_loopback_payload,
which are not sent on the wire. This ensures the 'ip' member is
4-byte aligned, preventing the following W=1 warning:
net/ethernet/sfc/falcon/selftest.c:43:15: error: field ip within 'struct ef4_loopback_payload' is less aligned than 'struct iphdr' and is usually due to 'struct ef4_loopback_payload' being packed, which can lead to unaligned accesses [-Werror,-Wunaligned-access]
struct iphdr ip;
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Edward Cree <ecree.xilinx@gmail.com>
---
drivers/net/ethernet/sfc/falcon/selftest.c | 45 +++++++++++++---------
1 file changed, 27 insertions(+), 18 deletions(-)
diff --git a/drivers/net/ethernet/sfc/falcon/selftest.c b/drivers/net/ethernet/sfc/falcon/selftest.c
index 6a454ac6f876..5fa3e745a525 100644
--- a/drivers/net/ethernet/sfc/falcon/selftest.c
+++ b/drivers/net/ethernet/sfc/falcon/selftest.c
@@ -39,12 +39,16 @@
* Falcon only performs RSS on TCP/UDP packets.
*/
struct ef4_loopback_payload {
+ char pad[2]; /* Ensures ip is 4-byte aligned */
struct ethhdr header;
struct iphdr ip;
struct udphdr udp;
__be16 iteration;
char msg[64];
} __packed;
+#define EF4_LOOPBACK_PAYLOAD_LEN (sizeof(struct ef4_loopback_payload) - \
+ offsetof(struct ef4_loopback_payload, \
+ header))
/* Loopback test source MAC address */
static const u8 payload_source[ETH_ALEN] __aligned(2) = {
@@ -284,7 +288,7 @@ void ef4_loopback_rx_packet(struct ef4_nic *efx,
const char *buf_ptr, int pkt_len)
{
struct ef4_loopback_state *state = efx->loopback_selftest;
- struct ef4_loopback_payload *received;
+ struct ef4_loopback_payload received;
struct ef4_loopback_payload *payload;
BUG_ON(!buf_ptr);
@@ -295,13 +299,14 @@ void ef4_loopback_rx_packet(struct ef4_nic *efx,
payload = &state->payload;
- received = (struct ef4_loopback_payload *) buf_ptr;
- received->ip.saddr = payload->ip.saddr;
+ memcpy(&received.header, buf_ptr,
+ min_t(int, pkt_len, EF4_LOOPBACK_PAYLOAD_LEN));
+ received.ip.saddr = payload->ip.saddr;
if (state->offload_csum)
- received->ip.check = payload->ip.check;
+ received.ip.check = payload->ip.check;
/* Check that header exists */
- if (pkt_len < sizeof(received->header)) {
+ if (pkt_len < sizeof(received.header)) {
netif_err(efx, drv, efx->net_dev,
"saw runt RX packet (length %d) in %s loopback "
"test\n", pkt_len, LOOPBACK_MODE(efx));
@@ -309,7 +314,7 @@ void ef4_loopback_rx_packet(struct ef4_nic *efx,
}
/* Check that the ethernet header exists */
- if (memcmp(&received->header, &payload->header, ETH_HLEN) != 0) {
+ if (memcmp(&received.header, &payload->header, ETH_HLEN) != 0) {
netif_err(efx, drv, efx->net_dev,
"saw non-loopback RX packet in %s loopback test\n",
LOOPBACK_MODE(efx));
@@ -317,16 +322,16 @@ void ef4_loopback_rx_packet(struct ef4_nic *efx,
}
/* Check packet length */
- if (pkt_len != sizeof(*payload)) {
+ if (pkt_len != EF4_LOOPBACK_PAYLOAD_LEN) {
netif_err(efx, drv, efx->net_dev,
"saw incorrect RX packet length %d (wanted %d) in "
- "%s loopback test\n", pkt_len, (int)sizeof(*payload),
- LOOPBACK_MODE(efx));
+ "%s loopback test\n", pkt_len,
+ (int)EF4_LOOPBACK_PAYLOAD_LEN, LOOPBACK_MODE(efx));
goto err;
}
/* Check that IP header matches */
- if (memcmp(&received->ip, &payload->ip, sizeof(payload->ip)) != 0) {
+ if (memcmp(&received.ip, &payload->ip, sizeof(payload->ip)) != 0) {
netif_err(efx, drv, efx->net_dev,
"saw corrupted IP header in %s loopback test\n",
LOOPBACK_MODE(efx));
@@ -334,7 +339,7 @@ void ef4_loopback_rx_packet(struct ef4_nic *efx,
}
/* Check that msg and padding matches */
- if (memcmp(&received->msg, &payload->msg, sizeof(received->msg)) != 0) {
+ if (memcmp(&received.msg, &payload->msg, sizeof(received.msg)) != 0) {
netif_err(efx, drv, efx->net_dev,
"saw corrupted RX packet in %s loopback test\n",
LOOPBACK_MODE(efx));
@@ -342,10 +347,10 @@ void ef4_loopback_rx_packet(struct ef4_nic *efx,
}
/* Check that iteration matches */
- if (received->iteration != payload->iteration) {
+ if (received.iteration != payload->iteration) {
netif_err(efx, drv, efx->net_dev,
"saw RX packet from iteration %d (wanted %d) in "
- "%s loopback test\n", ntohs(received->iteration),
+ "%s loopback test\n", ntohs(received.iteration),
ntohs(payload->iteration), LOOPBACK_MODE(efx));
goto err;
}
@@ -365,7 +370,8 @@ void ef4_loopback_rx_packet(struct ef4_nic *efx,
buf_ptr, pkt_len, 0);
netif_err(efx, drv, efx->net_dev, "expected packet:\n");
print_hex_dump(KERN_ERR, "", DUMP_PREFIX_OFFSET, 0x10, 1,
- &state->payload, sizeof(state->payload), 0);
+ &state->payload.header, EF4_LOOPBACK_PAYLOAD_LEN,
+ 0);
}
#endif
atomic_inc(&state->rx_bad);
@@ -387,14 +393,15 @@ static void ef4_iterate_state(struct ef4_nic *efx)
payload->ip.daddr = htonl(INADDR_LOOPBACK);
payload->ip.ihl = 5;
payload->ip.check = (__force __sum16) htons(0xdead);
- payload->ip.tot_len = htons(sizeof(*payload) - sizeof(struct ethhdr));
+ payload->ip.tot_len = htons(sizeof(*payload) -
+ offsetof(struct ef4_loopback_payload, ip));
payload->ip.version = IPVERSION;
payload->ip.protocol = IPPROTO_UDP;
/* Initialise udp header */
payload->udp.source = 0;
- payload->udp.len = htons(sizeof(*payload) - sizeof(struct ethhdr) -
- sizeof(struct iphdr));
+ payload->udp.len = htons(sizeof(*payload) -
+ offsetof(struct ef4_loopback_payload, udp));
payload->udp.check = 0; /* checksum ignored */
/* Fill out payload */
@@ -420,7 +427,7 @@ static int ef4_begin_loopback(struct ef4_tx_queue *tx_queue)
for (i = 0; i < state->packet_count; i++) {
/* Allocate an skb, holding an extra reference for
* transmit completion counting */
- skb = alloc_skb(sizeof(state->payload), GFP_KERNEL);
+ skb = alloc_skb(EF4_LOOPBACK_PAYLOAD_LEN, GFP_KERNEL);
if (!skb)
return -ENOMEM;
state->skbs[i] = skb;
@@ -431,6 +438,8 @@ static int ef4_begin_loopback(struct ef4_tx_queue *tx_queue)
payload = skb_put(skb, sizeof(state->payload));
memcpy(payload, &state->payload, sizeof(state->payload));
payload->ip.saddr = htonl(INADDR_LOOPBACK | (i << 2));
+ /* Strip off the leading padding */
+ skb_pull(skb, offsetof(struct ef4_loopback_payload, header));
/* Ensure everything we've written is visible to the
* interrupt handler. */
^ permalink raw reply related [flat|nested] 7+ messages in thread