wifi: ath11k: fix dest ring-buffer corruption
Subsystems (2)
v2 cover wifi: ath11k: fix dest ring-buffer corruption
As a follow up to commits:
6d037a372f81 ("wifi: ath11k: fix ring-buffer corruption")
ab52e3e44fe9 ("wifi: ath11k: fix rx completion meta data corruption")add the remaining missing memory barriers to make sure that destination ring descriptors are read after the head pointers to avoid using stale data on weakly ordered architectures like aarch64.
Also switch back to plain accesses for the descriptor fields which is sufficient after the memory barrier.
New in v2 are two patches that adds the missing barriers also for source rings and when updating the tail pointer for destination rings.
To avoid leaking ring details from the "hal" (lmac or non-lmac), the barriers are added to the ath11k_hal_srng_access_end() helper. For symmetry I therefore moved also the dest ring barriers into ath11k_hal_srng_access_begin() and made the barrier conditional.
[ Due to this change I did not add Miaoqing's reviewed-by tag. ]
Johan
Changes in v2:
- add tested-on tags to plain access patches
- move destination barriers into begin helper
- fix source ring corruption (new patch)
- fix dest ring corruption when ring is full (new patch)
Johan Hovold (5):
wifi: ath11k: fix dest ring-buffer corruption
wifi: ath11k: use plain access for descriptor length
wifi: ath11k: use plain accesses for monitor descriptor
wifi: ath11k: fix source ring-buffer corruption
wifi: ath11k: fix dest ring-buffer corruption when ring is full
drivers/net/wireless/ath/ath11k/ce.c | 3 --- drivers/net/wireless/ath/ath11k/dp_rx.c | 25 +++++++----------- drivers/net/wireless/ath/ath11k/hal.c | 35 +++++++++++++++++++++---- 3 files changed, 39 insertions(+), 24 deletions(-)
Signature · 1 line
2.49.0
PATCH v2 1/5 wifi: ath11k: fix dest ring-buffer corruption
Add the missing memory barrier to make sure that destination ring descriptors are read after the head pointers to avoid using stale data on weakly ordered architectures like aarch64.
The barrier is added to the ath11k_hal_srng_access_begin() helper for symmetry with follow-on fixes for source ring buffer corruption which will add barriers to ath11k_hal_srng_access_end().
Tested-on: WCN6855 hw2.1 WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.41
--- drivers/net/wireless/ath/ath11k/ce.c | 3 --- drivers/net/wireless/ath/ath11k/dp_rx.c | 3 --- drivers/net/wireless/ath/ath11k/hal.c | 12 +++++++++++- 3 files changed, 11 insertions(+), 7 deletions(-)
drivers/net/wireless/ath/ath11k/ce.c +0 -3
@@ -393,9 +393,6 @@ static int ath11k_ce_completed_recv_next(struct ath11k_ce_pipe *pipe, goto err; } -/* Make sure descriptor is read after the head pointer. */ -dma_rmb (); - *nbytes =ath11k_hal_ce_dst_status_get_length (desc); *skb = pipe->dest_ring->skb[sw_index];
drivers/net/wireless/ath/ath11k/dp_rx.c +0 -3
@@ -2650,9 +2650,6 @@ int ath11k_dp_process_rx(struct ath11k_base *ab, int ring_id, try_again:ath11k_hal_srng_access_begin (ab, srng); -/* Make sure descriptor is read after the head pointer. */ -dma_rmb (); -while (likely (desc = (struct hal_reo_dest_ring *)ath11k_hal_srng_dst_get_next_entry (ab, srng))) {
drivers/net/wireless/ath/ath11k/hal.c +11 -1
@@ -823,13 +823,23 @@ u32 *ath11k_hal_srng_src_peek(struct ath11k_base *ab, struct hal_srng *srng)void ath11k_hal_srng_access_begin (struct ath11k_base *ab,struct hal_srng *srng) { +u32 hp; +lockdep_assert_held (&srng->lock);if (srng->ring_dir ==HAL_SRNG_DIR_SRC ) { srng->u.src_ring.cached_tp = *(volatile u32 *)srng->u.src_ring.tp_addr; }else { - srng->u.dst_ring.cached_hp =READ_ONCE (*srng->u.dst_ring.hp_addr); + hp =READ_ONCE (*srng->u.dst_ring.hp_addr); + +if (hp != srng->u.dst_ring.cached_hp) { + srng->u.dst_ring.cached_hp = hp; +/* Make sure descriptor is read after the head +* pointer. +*/ +dma_rmb (); + }/* Try to prefetch the next descriptor in the ring */ if (srng->flags &HAL_SRNG_FLAGS_CACHED )
Signature · 1 line
2.49.0
Quoted 57 lines · Johan Hovold
Add the missing memory barrier to make sure that destination ring descriptors are read after the head pointers to avoid using stale data on weakly ordered architectures like aarch64.
The barrier is added to the
ath11k_hal_srng_access_begin()helper for symmetry with follow-on fixes for source ring buffer corruption which will add barriers toath11k_hal_srng_access_end().Tested-on: WCN6855 hw2.1 WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.41
Fixes d5c65159f289 ("ath11k: driver for Qualcomm IEEE 802.11ax devices")Cc [email protected] # 5.6Signed-off-by Johan Hovold <[email protected]>--- drivers/net/wireless/ath/ath11k/ce.c | 3 --- drivers/net/wireless/ath/ath11k/dp_rx.c | 3 --- drivers/net/wireless/ath/ath11k/hal.c | 12 +++++++++++- 3 files changed, 11 insertions(+), 7 deletions(-)drivers/net/wireless/ath/ath11k/ce.c +0
-3@@ -393,9 +393,6 @@ static int ath11k_ce_completed_recv_next(struct ath11k_ce_pipe *pipe, goto err; } -/* Make sure descriptor is read after the head pointer. */ -dma_rmb (); - *nbytes =ath11k_hal_ce_dst_status_get_length (desc); *skb = pipe->dest_ring->skb[sw_index];drivers/net/wireless/ath/ath11k/dp_rx.c +0
-3@@ -2650,9 +2650,6 @@ int ath11k_dp_process_rx(struct ath11k_base *ab, int ring_id, try_again:ath11k_hal_srng_access_begin (ab, srng); -/* Make sure descriptor is read after the head pointer. */ -dma_rmb (); -while (likely (desc = (struct hal_reo_dest_ring *)ath11k_hal_srng_dst_get_next_entry (ab, srng))) {drivers/net/wireless/ath/ath11k/hal.c +2
-0@@ -823,13 +823,23 @@ u32 *ath11k_hal_srng_src_peek(struct ath11k_base *ab, struct hal_srng *srng)void ath11k_hal_srng_access_begin (struct ath11k_base *ab,struct hal_srng *srng) { +u32 hp; +
drivers/net/wireless/ath/ath11k/hal.c u32 *ath11k_hal_srng_src_peek(struct ath11k_base *ab, struct hal_srng *srng) · line 836
Quoted 10 lines
drivers/net/wireless/ath/ath11k/hal.c +3
-1lockdep_assert_held (&srng->lock);if (srng->ring_dir ==HAL_SRNG_DIR_SRC ) { srng->u.src_ring.cached_tp = *(volatile u32 *)srng->u.src_ring.tp_addr; }else { - srng->u.dst_ring.cached_hp =READ_ONCE (*srng->u.dst_ring.hp_addr); + hp =READ_ONCE (*srng->u.dst_ring.hp_addr); + +if (hp != srng->u.dst_ring.cached_hp) {
My ath12k comments apply here: this consumes more CPU cycles
Quoted 9 lines
drivers/net/wireless/ath/ath11k/hal.c +6
-0+ srng->u.dst_ring.cached_hp = hp; +/* Make sure descriptor is read after the head +* pointer. +*/ +dma_rmb (); + }/* Try to prefetch the next descriptor in the ring */ if (srng->flags &HAL_SRNG_FLAGS_CACHED )
Quoted 66 lines · Johan Hovold
Add the missing memory barrier to make sure that destination ring descriptors are read after the head pointers to avoid using stale data on weakly ordered architectures like aarch64.
The barrier is added to the
ath11k_hal_srng_access_begin()helper for symmetry with follow-on fixes for source ring buffer corruption which will add barriers toath11k_hal_srng_access_end().Tested-on: WCN6855 hw2.1 WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.41
Fixes d5c65159f289 ("ath11k: driver for Qualcomm IEEE 802.11ax devices")Cc [email protected] # 5.6Signed-off-by Johan Hovold <[email protected]>--- drivers/net/wireless/ath/ath11k/ce.c | 3 --- drivers/net/wireless/ath/ath11k/dp_rx.c | 3 --- drivers/net/wireless/ath/ath11k/hal.c | 12 +++++++++++- 3 files changed, 11 insertions(+), 7 deletions(-)drivers/net/wireless/ath/ath11k/ce.c +0
-3@@ -393,9 +393,6 @@ static int ath11k_ce_completed_recv_next(struct ath11k_ce_pipe *pipe, goto err; } -/* Make sure descriptor is read after the head pointer. */ -dma_rmb (); - *nbytes =ath11k_hal_ce_dst_status_get_length (desc); *skb = pipe->dest_ring->skb[sw_index];drivers/net/wireless/ath/ath11k/dp_rx.c +0
-3@@ -2650,9 +2650,6 @@ int ath11k_dp_process_rx(struct ath11k_base *ab, int ring_id, try_again:ath11k_hal_srng_access_begin (ab, srng); -/* Make sure descriptor is read after the head pointer. */ -dma_rmb (); -while (likely (desc = (struct hal_reo_dest_ring *)ath11k_hal_srng_dst_get_next_entry (ab, srng))) {drivers/net/wireless/ath/ath11k/hal.c +4
-1@@ -823,13 +823,23 @@ u32 *ath11k_hal_srng_src_peek(struct ath11k_base *ab, struct hal_srng *srng)void ath11k_hal_srng_access_begin (struct ath11k_base *ab,struct hal_srng *srng) { +u32 hp; +lockdep_assert_held (&srng->lock);if (srng->ring_dir ==HAL_SRNG_DIR_SRC ) { srng->u.src_ring.cached_tp = *(volatile u32 *)srng->u.src_ring.tp_addr; }else { - srng->u.dst_ring.cached_hp =READ_ONCE (*srng->u.dst_ring.hp_addr); + hp =READ_ONCE (*srng->u.dst_ring.hp_addr); +
drivers/net/wireless/ath/ath11k/hal.c u32 *ath11k_hal_srng_src_peek(struct ath11k_base *ab, struct hal_srng *srng) · line 845
Quoted 10 lines
drivers/net/wireless/ath/ath11k/hal.c +7
-0+if (hp != srng->u.dst_ring.cached_hp) { + srng->u.dst_ring.cached_hp = hp; +/* Make sure descriptor is read after the head +* pointer. +*/ +dma_rmb (); + }/* Try to prefetch the next descriptor in the ring */ if (srng->flags &HAL_SRNG_FLAGS_CACHED )
PATCH v2 2/5 wifi: ath11k: use plain access for descriptor length
In reply to Johan HovoldThe read memory barrier added by commit 6d037a372f81 ("wifi: ath11k: fix ring-buffer corruption") is enough to guarantee ordering also for plain descriptor accesses if the length helper is ever inlined so drop the unnecessary READ_ONCE().
Tested-on: WCN6855 hw2.1 WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.41
--- drivers/net/wireless/ath/ath11k/hal.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
drivers/net/wireless/ath/ath11k/hal.c +1 -1
@@ -599,7 +599,7 @@ u32 ath11k_hal_ce_dst_status_get_length(void *buf)struct hal_ce_srng_dst_status_desc *desc = buf;u32 len; - len =FIELD_GET (HAL_CE_DST_STATUS_DESC_FLAGS_LEN ,READ_ONCE (desc->flags)); + len =FIELD_GET (HAL_CE_DST_STATUS_DESC_FLAGS_LEN , desc->flags); desc->flags &= ~HAL_CE_DST_STATUS_DESC_FLAGS_LEN ;return len;
Signature · 1 line
2.49.0
Re: [PATCH v2 2/5] wifi: ath11k: use plain access for descriptor length
Quoted 17 lines · Johan Hovold
The read memory barrier added by commit
6d037a372f81("wifi: ath11k: fix ring-buffer corruption") is enough to guarantee ordering also for plain descriptor accesses if the length helper is ever inlined so drop the unnecessaryREAD_ONCE().Tested-on: WCN6855 hw2.1 WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.41
Signed-off-by Johan Hovold <[email protected]>--- drivers/net/wireless/ath/ath11k/hal.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)drivers/net/wireless/ath/ath11k/hal.c +0
-0
drivers/net/wireless/ath/ath11k/hal.c u32 ath11k_hal_ce_dst_status_get_length(void *buf) · line 605
Quoted 8 lines
drivers/net/wireless/ath/ath11k/hal.c +1
-1@@ -599,7 +599,7 @@ u32 ath11k_hal_ce_dst_status_get_length(void *buf)struct hal_ce_srng_dst_status_desc *desc = buf;u32 len; - len =FIELD_GET (HAL_CE_DST_STATUS_DESC_FLAGS_LEN ,READ_ONCE (desc->flags)); + len =FIELD_GET (HAL_CE_DST_STATUS_DESC_FLAGS_LEN , desc->flags); desc->flags &= ~HAL_CE_DST_STATUS_DESC_FLAGS_LEN ;return len;
PATCH v2 3/5 wifi: ath11k: use plain accesses for monitor descriptor
In reply to Johan HovoldThe read memory barrier added by commit ab52e3e44fe9 ("wifi: ath11k: fix rx completion meta data corruption") is enough to guarantee ordering also for plain descriptor accesses so drop the unnecessary READ_ONCE().
Tested-on: WCN6855 hw2.1 WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.41
--- drivers/net/wireless/ath/ath11k/dp_rx.c | 22 +++++++++------------- 1 file changed, 9 insertions(+), 13 deletions(-)
drivers/net/wireless/ath/ath11k/dp_rx.c +9 -13
@@ -2637,7 +2637,7 @@ int ath11k_dp_process_rx(struct ath11k_base *ab, int ring_id,struct ath11k *ar;struct hal_reo_dest_ring *desc;enum hal_reo_dest_ring_push_reason push_reason; -u32 cookie, info0, rx_msdu_info0, rx_mpdu_info0; +u32 cookie;int i;for (i =0 ; i <MAX_RADIOS ; i++)
@@ -2654,7 +2654,7 @@ int ath11k_dp_process_rx(struct ath11k_base *ab, int ring_id, (struct hal_reo_dest_ring *)ath11k_hal_srng_dst_get_next_entry(ab, srng))) { cookie =FIELD_GET (BUFFER_ADDR_INFO1_SW_COOKIE , -READ_ONCE (desc->buf_addr_info.info1)); + desc->buf_addr_info.info1); buf_id =FIELD_GET (DP_RXDMA_BUF_COOKIE_BUF_ID , cookie); mac_id =FIELD_GET (DP_RXDMA_BUF_COOKIE_PDEV_ID , cookie);
@@ -2683,9 +2683,8 @@ int ath11k_dp_process_rx(struct ath11k_base *ab, int ring_id, num_buffs_reaped[mac_id]++; - info0 =READ_ONCE (desc->info0); push_reason =FIELD_GET (HAL_REO_DEST_RING_INFO0_PUSH_REASON , - info0); + desc->info0);if (unlikely (push_reason !=HAL_REO_DEST_RING_PUSH_REASON_ROUTING_INSTRUCTION )) {dev_kfree_skb_any (msdu);
@@ -2693,21 +2692,18 @@ int ath11k_dp_process_rx(struct ath11k_base *ab, int ring_id,continue ; } - rx_msdu_info0 =READ_ONCE (desc->rx_msdu_info.info0); - rx_mpdu_info0 =READ_ONCE (desc->rx_mpdu_info.info0); - - rxcb->is_first_msdu = !!(rx_msdu_info0 & + rxcb->is_first_msdu = !!(desc->rx_msdu_info.info0 &RX_MSDU_DESC_INFO0_FIRST_MSDU_IN_MPDU ); - rxcb->is_last_msdu = !!(rx_msdu_info0 & + rxcb->is_last_msdu = !!(desc->rx_msdu_info.info0 &RX_MSDU_DESC_INFO0_LAST_MSDU_IN_MPDU ); - rxcb->is_continuation = !!(rx_msdu_info0 & + rxcb->is_continuation = !!(desc->rx_msdu_info.info0 &RX_MSDU_DESC_INFO0_MSDU_CONTINUATION ); rxcb->peer_id =FIELD_GET (RX_MPDU_DESC_META_DATA_PEER_ID , -READ_ONCE (desc->rx_mpdu_info.meta_data)); + desc->rx_mpdu_info.meta_data); rxcb->seq_no =FIELD_GET (RX_MPDU_DESC_INFO0_SEQ_NUM , - rx_mpdu_info0); + desc->rx_mpdu_info.info0); rxcb->tid =FIELD_GET (HAL_REO_DEST_RING_INFO0_RX_QUEUE_NUM , - info0); + desc->info0); rxcb->mac_id = mac_id;__skb_queue_tail (&msdu_list[mac_id], msdu);
Signature · 1 line
2.49.0
Re: [PATCH v2 3/5] wifi: ath11k: use plain accesses for monitor descriptor
Quoted 62 lines · Johan Hovold
The read memory barrier added by commit
ab52e3e44fe9("wifi: ath11k: fix rx completion meta data corruption") is enough to guarantee ordering also for plain descriptor accesses so drop the unnecessaryREAD_ONCE().Tested-on: WCN6855 hw2.1 WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.41
Signed-off-by Johan Hovold <[email protected]>--- drivers/net/wireless/ath/ath11k/dp_rx.c | 22 +++++++++------------- 1 file changed, 9 insertions(+), 13 deletions(-)drivers/net/wireless/ath/ath11k/dp_rx.c +6
-11@@ -2637,7 +2637,7 @@ int ath11k_dp_process_rx(struct ath11k_base *ab, int ring_id,struct ath11k *ar;struct hal_reo_dest_ring *desc;enum hal_reo_dest_ring_push_reason push_reason; -u32 cookie, info0, rx_msdu_info0, rx_mpdu_info0; +u32 cookie;int i;for (i =0 ; i <MAX_RADIOS ; i++)@@ -2654,7 +2654,7 @@ int ath11k_dp_process_rx(struct ath11k_base *ab, int ring_id, (struct hal_reo_dest_ring *)ath11k_hal_srng_dst_get_next_entry(ab, srng))) { cookie =FIELD_GET (BUFFER_ADDR_INFO1_SW_COOKIE , -READ_ONCE (desc->buf_addr_info.info1)); + desc->buf_addr_info.info1); buf_id =FIELD_GET (DP_RXDMA_BUF_COOKIE_BUF_ID , cookie); mac_id =FIELD_GET (DP_RXDMA_BUF_COOKIE_PDEV_ID , cookie);@@ -2683,9 +2683,8 @@ int ath11k_dp_process_rx(struct ath11k_base *ab, int ring_id, num_buffs_reaped[mac_id]++; - info0 =READ_ONCE (desc->info0); push_reason =FIELD_GET (HAL_REO_DEST_RING_INFO0_PUSH_REASON , - info0); + desc->info0);if (unlikely (push_reason !=HAL_REO_DEST_RING_PUSH_REASON_ROUTING_INSTRUCTION )) {dev_kfree_skb_any (msdu);@@ -2693,21 +2692,18 @@ int ath11k_dp_process_rx(struct ath11k_base *ab, int ring_id,continue ; } - rx_msdu_info0 =READ_ONCE (desc->rx_msdu_info.info0); - rx_mpdu_info0 =READ_ONCE (desc->rx_mpdu_info.info0); - - rxcb->is_first_msdu = !!(rx_msdu_info0 & + rxcb->is_first_msdu = !!(desc->rx_msdu_info.info0 &RX_MSDU_DESC_INFO0_FIRST_MSDU_IN_MPDU ); - rxcb->is_last_msdu = !!(rx_msdu_info0 & + rxcb->is_last_msdu = !!(desc->rx_msdu_info.info0 &RX_MSDU_DESC_INFO0_LAST_MSDU_IN_MPDU ); - rxcb->is_continuation = !!(rx_msdu_info0 & + rxcb->is_continuation = !!(desc->rx_msdu_info.info0 &RX_MSDU_DESC_INFO0_MSDU_CONTINUATION ); rxcb->peer_id = FIELD_GET(RX_MPDU_DESC_META_DATA_PEER_ID, -READ_ONCE (desc->rx_mpdu_info.meta_data));
drivers/net/wireless/ath/ath11k/dp_rx.c int ath11k_dp_process_rx(struct ath11k_base *ab, int ring_id, · line 2709
Quoted 10 lines
drivers/net/wireless/ath/ath11k/dp_rx.c +3
-2+ desc->rx_mpdu_info.meta_data); rxcb->seq_no =FIELD_GET (RX_MPDU_DESC_INFO0_SEQ_NUM , - rx_mpdu_info0); + desc->rx_mpdu_info.info0); rxcb->tid =FIELD_GET (HAL_REO_DEST_RING_INFO0_RX_QUEUE_NUM , - info0); + desc->info0); rxcb->mac_id = mac_id;__skb_queue_tail (&msdu_list[mac_id], msdu);
PATCH v2 4/5 wifi: ath11k: fix source ring-buffer corruption
In reply to Johan HovoldAdd the missing memory barrier to make sure that LMAC source ring descriptors are written before updating the head pointer to avoid passing stale data to the firmware on weakly ordered architectures like aarch64.
Note that non-LMAC rings use MMIO write accessors which have the required write memory barrier.
Tested-on: WCN6855 hw2.1 WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.41
--- drivers/net/wireless/ath/ath11k/hal.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)
drivers/net/wireless/ath/ath11k/hal.c +9 -1
@@ -862,7 +862,11 @@ void ath11k_hal_srng_access_end(struct ath11k_base *ab, struct hal_srng *srng)if (srng->ring_dir ==HAL_SRNG_DIR_SRC ) { srng->u.src_ring.last_tp = *(volatile u32 *)srng->u.src_ring.tp_addr; - *srng->u.src_ring.hp_addr = srng->u.src_ring.hp; +/* Make sure descriptor is written before updating the +* head pointer. +*/ +dma_wmb (); +WRITE_ONCE (*srng->u.src_ring.hp_addr, srng->u.src_ring.hp); }else { srng->u.dst_ring.last_hp = *srng->u.dst_ring.hp_addr; *srng->u.dst_ring.tp_addr = srng->u.dst_ring.tp;
@@ -871,6 +875,10 @@ void ath11k_hal_srng_access_end(struct ath11k_base *ab, struct hal_srng *srng)if (srng->ring_dir ==HAL_SRNG_DIR_SRC ) { srng->u.src_ring.last_tp = *(volatile u32 *)srng->u.src_ring.tp_addr; +/* Assume implementation use an MMIO write accessor +* which has the required wmb() so that the descriptor +* is written before the updating the head pointer. +*/ ath11k_hif_write32(ab, (unsigned long)srng->u.src_ring.hp_addr - (unsigned long)ab->mem,
Signature · 1 line
2.49.0
Re: [PATCH v2 4/5] wifi: ath11k: fix source ring-buffer corruption
Quoted 35 lines · Johan Hovold
Add the missing memory barrier to make sure that LMAC source ring descriptors are written before updating the head pointer to avoid passing stale data to the firmware on weakly ordered architectures like aarch64.
Note that non-LMAC rings use MMIO write accessors which have the required write memory barrier.
Tested-on: WCN6855 hw2.1 WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.41
Fixes d5c65159f289 ("ath11k: driver for Qualcomm IEEE 802.11ax devices")Cc [email protected] # 5.6Signed-off-by Johan Hovold <[email protected]>--- drivers/net/wireless/ath/ath11k/hal.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)drivers/net/wireless/ath/ath11k/hal.c +5
-1@@ -862,7 +862,11 @@ void ath11k_hal_srng_access_end(struct ath11k_base *ab, struct hal_srng *srng)if (srng->ring_dir ==HAL_SRNG_DIR_SRC ) { srng->u.src_ring.last_tp = *(volatile u32 *)srng->u.src_ring.tp_addr; - *srng->u.src_ring.hp_addr = srng->u.src_ring.hp; +/* Make sure descriptor is written before updating the +* head pointer. +*/ +dma_wmb (); +WRITE_ONCE (*srng->u.src_ring.hp_addr, srng->u.src_ring.hp); }else { srng->u.dst_ring.last_hp = *srng->u.dst_ring.hp_addr; *srng->u.dst_ring.tp_addr = srng->u.dst_ring.tp;
drivers/net/wireless/ath/ath11k/hal.c void ath11k_hal_srng_access_end(struct ath11k_base *ab, struct hal_srng *srng) · line 884
Quoted 10 lines
drivers/net/wireless/ath/ath11k/hal.c +4
-0@@ -871,6 +875,10 @@ void ath11k_hal_srng_access_end(struct ath11k_base *ab, struct hal_srng *srng)if (srng->ring_dir ==HAL_SRNG_DIR_SRC ) { srng->u.src_ring.last_tp = *(volatile u32 *)srng->u.src_ring.tp_addr; +/* Assume implementation use an MMIO write accessor +* which has the required wmb() so that the descriptor +* is written before the updating the head pointer. +*/ ath11k_hif_write32(ab, (unsigned long)srng->u.src_ring.hp_addr - (unsigned long)ab->mem,
PATCH v2 5/5 wifi: ath11k: fix dest ring-buffer corruption when ring is full
In reply to Johan HovoldAdd the missing memory barriers to make sure that destination ring descriptors are read before updating the tail pointer (and passing ownership to the device) to avoid memory corruption on weakly ordered architectures like aarch64 when the ring is full.
Tested-on: WCN6855 hw2.1 WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.41
--- drivers/net/wireless/ath/ath11k/hal.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-)
drivers/net/wireless/ath/ath11k/hal.c +9 -2
@@ -854,7 +854,6 @@ void ath11k_hal_srng_access_end(struct ath11k_base *ab, struct hal_srng *srng) {lockdep_assert_held (&srng->lock); -/* TODO: See if we need a write memory barrier here */ if (srng->flags &HAL_SRNG_FLAGS_LMAC_RING ) {/* For LMAC rings, ring pointer updates are done through FW and * hence written to a shared memory location that is read by FW
@@ -869,7 +868,11 @@ void ath11k_hal_srng_access_end(struct ath11k_base *ab, struct hal_srng *srng)WRITE_ONCE (*srng->u.src_ring.hp_addr, srng->u.src_ring.hp); }else { srng->u.dst_ring.last_hp = *srng->u.dst_ring.hp_addr; - *srng->u.dst_ring.tp_addr = srng->u.dst_ring.tp; +/* Make sure descriptor is read before updating the +* tail pointer. +*/ +dma_mb (); +WRITE_ONCE (*srng->u.dst_ring.tp_addr, srng->u.dst_ring.tp); } }else {if (srng->ring_dir ==HAL_SRNG_DIR_SRC ) {
@@ -885,6 +888,10 @@ void ath11k_hal_srng_access_end(struct ath11k_base *ab, struct hal_srng *srng) srng->u.src_ring.hp); }else { srng->u.dst_ring.last_hp = *srng->u.dst_ring.hp_addr; +/* Make sure descriptor is read before updating the +* tail pointer. +*/ +mb (); ath11k_hif_write32(ab, (unsigned long)srng->u.dst_ring.tp_addr - (unsigned long)ab->mem,
Signature · 1 line
2.49.0
Re: [PATCH v2 5/5] wifi: ath11k: fix dest ring-buffer corruption when ring is full
Quoted 40 lines · Johan Hovold
Add the missing memory barriers to make sure that destination ring descriptors are read before updating the tail pointer (and passing ownership to the device) to avoid memory corruption on weakly ordered architectures like aarch64 when the ring is full.
Tested-on: WCN6855 hw2.1 WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.41
Fixes d5c65159f289 ("ath11k: driver for Qualcomm IEEE 802.11ax devices")Cc [email protected] # 5.6Signed-off-by Johan Hovold <[email protected]>--- drivers/net/wireless/ath/ath11k/hal.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-)drivers/net/wireless/ath/ath11k/hal.c +5
-2@@ -854,7 +854,6 @@ void ath11k_hal_srng_access_end(struct ath11k_base *ab, struct hal_srng *srng) {lockdep_assert_held (&srng->lock); -/* TODO: See if we need a write memory barrier here */ if (srng->flags &HAL_SRNG_FLAGS_LMAC_RING ) {/* For LMAC rings, ring pointer updates are done through FW and * hence written to a shared memory location that is read by FW @@ -869,7 +868,11 @@ void ath11k_hal_srng_access_end(struct ath11k_base *ab, struct hal_srng *srng)WRITE_ONCE (*srng->u.src_ring.hp_addr, srng->u.src_ring.hp); }else { srng->u.dst_ring.last_hp = *srng->u.dst_ring.hp_addr; - *srng->u.dst_ring.tp_addr = srng->u.dst_ring.tp; +/* Make sure descriptor is read before updating the +* tail pointer. +*/ +dma_mb (); +WRITE_ONCE (*srng->u.dst_ring.tp_addr, srng->u.dst_ring.tp); } }else {if (srng->ring_dir ==HAL_SRNG_DIR_SRC ) {
drivers/net/wireless/ath/ath11k/hal.c void ath11k_hal_srng_access_end(struct ath11k_base *ab, struct hal_srng *srng) · line 897
Quoted 10 lines
drivers/net/wireless/ath/ath11k/hal.c +4
-0@@ -885,6 +888,10 @@ void ath11k_hal_srng_access_end(struct ath11k_base *ab, struct hal_srng *srng) srng->u.src_ring.hp); }else { srng->u.dst_ring.last_hp = *srng->u.dst_ring.hp_addr; +/* Make sure descriptor is read before updating the +* tail pointer. +*/ +mb (); ath11k_hif_write32(ab, (unsigned long)srng->u.dst_ring.tp_addr - (unsigned long)ab->mem,
Jeff Johnson
AppliedQuoted 10 lines · Johan Hovold
As a follow up to commits:
6d037a372f81 ("wifi: ath11k: fix ring-buffer corruption") ab52e3e44fe9 ("wifi: ath11k: fix rx completion meta data corruption")add the remaining missing memory barriers to make sure that destination ring descriptors are read after the head pointers to avoid using stale data on weakly ordered architectures like aarch64.
[...]
Applied, thanks!
[1/5] wifi: ath11k: fix dest ring-buffer corruption
commit: 8c1ba5091fa9a2d1478da63173b16a701bdf86bb
[2/5] wifi: ath11k: use plain access for descriptor length
commit: 3a690e9091ec07f70cedd9a7dcc074c8554f1bed
[3/5] wifi: ath11k: use plain accesses for monitor descriptor
commit: 4aba95fb1faed7fe7f6e1edfb60c333e0275dfc1
[4/5] wifi: ath11k: fix source ring-buffer corruption
commit: 6efa0df54022c6c9fd4d294b87622c7fcdc418c8
[5/5] wifi: ath11k: fix dest ring-buffer corruption when ring is full
commit: aa6956150f820e6a6deba44be325ddfcb5b10f88Best regards,
Signature · 1 line
Jeff Johnson <[email protected]>