CVE-2026-74698

Description

In the Linux kernel, the following vulnerability has been resolved: net/mlx5e: fix BQL reset on SQ re-activation mlx5e_queue_start() deactivates and re-activates all channels but closes only the queue being restarted. mlx5e_activate_txqsq() then unconditionally calls netdev_tx_reset_queue(), zeroing the BQL counters of channels that kept their in-flight TX WQEs. The next completion then over-charges and trips the BUG_ON() in dql_completed(): kernel BUG at lib/dynamic_queue_limits.c:99! RIP: 0010:dql_completed+0x23d/0x280 Call Trace: <IRQ> mlx5e_poll_tx_cq+0x668/0xa60 mlx5e_napi_poll+0x5b/0x7b0 net_rx_action+0x15a/0x580 Reset BQL only when the SQ has no bytes in flight (sq->cc == sq->pc). In the case that reset is skipped, the outstanding WQEs will eventually complete and rebalance the dql. The dql->limit is carried across the reset.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

References

• https://git.kernel.org/stable/c/88664c48d7d1eca8e1ac92da85c89c26af741cf1 ↗
• https://git.kernel.org/stable/c/d2897717cd222e575599d903d885c48602699800 ↗
• https://git.kernel.org/stable/c/e7386770be1bf810bcd6af39d1e4bfeab3408430 ↗