> -----Original Message-----
> From: Bart Van Assche <[email protected]>
> Sent: Friday, March 20, 2026 10:28 PM
> To: Nguyen, Anthony L <[email protected]>
> Cc: Kitszel, Przemyslaw <[email protected]>; intel-wired-
> [email protected]; Bart Van Assche <[email protected]>; Loktionov,
> Aleksandr <[email protected]>
> Subject: [PATCH iwl-net v4] ice: fix locking in ice_dcb_rebuild()
>
> Move the mutex_lock() call up to prevent that DCB settings change
> after the first ice_query_port_ets() call. The second
> ice_query_port_ets() call in ice_dcb_rebuild() is already protected by
> pf->tc_mutex.
>
> This also fixes a bug in an error path, as before taking the first
> "goto dcb_error" in the function jumped over mutex_lock() to
> mutex_unlock().
>
> This bug has been detected by the clang thread-safety analyzer.
>
> Cc: Aleksandr Loktionov <[email protected]>
> Cc: [email protected]
> Fixes: 242b5e068b25 ("ice: Fix DCB rebuild after reset")
> Signed-off-by: Bart Van Assche <[email protected]>
> ---
>
> v4 (this patch): Changed "[PATCH] iwl-net:" into "[PATCH iwl-net]".
>
> v3 (2026-03-20): Modified patch description. See also
> https://lore.kernel.org/all/20260223220102.2158611-20-
> [email protected]/#t
>
> v2 (2026-02-23): Combined the two patches into one patch and
> increased the amount of code covered by tc_mutex. See also
> https://lore.kernel.org/all/20260223220102.2158611-20-
> [email protected]/
>
> v1 (2025-02-06): Two patches. See also
> https://lore.kernel.org/all/20250206175114.1974171-16-
> [email protected]/
>
> drivers/net/ethernet/intel/ice/ice_dcb_lib.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/net/ethernet/intel/ice/ice_dcb_lib.c
> b/drivers/net/ethernet/intel/ice/ice_dcb_lib.c
> index bd77f1c001ee..78ded6876581 100644
> --- a/drivers/net/ethernet/intel/ice/ice_dcb_lib.c
> +++ b/drivers/net/ethernet/intel/ice/ice_dcb_lib.c
> @@ -537,14 +537,14 @@ void ice_dcb_rebuild(struct ice_pf *pf)
> struct ice_dcbx_cfg *err_cfg;
> int ret;
>
> + mutex_lock(&pf->tc_mutex);
> +
> ret = ice_query_port_ets(pf->hw.port_info, &buf, sizeof(buf),
> NULL);
> if (ret) {
> dev_err(dev, "Query Port ETS failed\n");
> goto dcb_error;
> }
>
> - mutex_lock(&pf->tc_mutex);
> -
> if (!pf->hw.port_info->qos_cfg.is_sw_lldp)
> ice_cfg_etsrec_defaults(pf->hw.port_info);
>
Reviewed-by: Aleksandr Loktionov <[email protected]>
