[PATCH v3 0/4] wifi: ath12k: fix dest ring-buffer corruption

Johan Hovold
2025-06-17T08:48:48Z

As a follow up to commit:

b67d2cf14ea ("wifi: ath12k: fix ring-buffer 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 add 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 ath12k_hal_srng_access_end() helper. For
symmetry I therefore moved also the dest ring barriers into
ath12k_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 v3:
- drop reference to commit 51ad34a47e9f ("wifi: ath12k: Add drop
descriptor handling for monitor ring") from the commit message of
patch 1/4

Changes in v2:
- add tested-on tags to plain access patch
- move destination barriers into begin helper
- fix source ring corruption (new patch)
- fix dest ring corruption when ring is full (new patch)

Johan Hovold (4):
wifi: ath12k: fix dest ring-buffer corruption
wifi: ath12k: use plain access for descriptor length
wifi: ath12k: fix source ring-buffer corruption
wifi: ath12k: fix dest ring-buffer corruption when ring is full

drivers/net/wireless/ath/ath12k/ce.c | 3 --
drivers/net/wireless/ath/ath12k/hal.c | 40 ++++++++++++++++++++++-----
2 files changed, 33 insertions(+), 10 deletions(-)

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2.49.0