| Message ID | 20241119-ath11k-noinline-v1-2-4ec0a8aa30b2@quicinc.com |
|---|---|
| State | New |
| Headers | show |
| Series | wifi: ath11k: Fix clang+KASAN stack frame size warnings | expand |
Jeff Johnson <quic_jjohnson@quicinc.com> writes: > When compiling the ath11k driver using clang with KASAN enabled, the > following warning is observed: > > drivers/net/wireless/ath/ath11k/dp_rx.c:5244:5: warning: stack frame size (1304) exceeds limit (1024) in 'ath11k_dp_rx_process_mon_status' [-Wframe-larger-than] > > This is similar to the issue found in ath12k/qmi.c that was discussed > in [1] and fixed with [2]. The issue is that clang inlining can > explode stack usage. > > ath11k_dp_rx_process_mon_status() itself is a pretty > lightweight function, but it dispatches to several other functions > which do the real work: > > ath11k_dp_rx_process_mon_status() > ath11k_dp_rx_reap_mon_status_ring() > ath11k_dp_rx_mon_dest_process() > ath11k_dp_rx_mon_mpdu_pop() * > ath11k_dp_rx_mon_deliver() > ath11k_dp_rx_mon_merg_msdus() > ath11k_dp_rx_deliver_msdu() > ath11k_dp_rx_update_peer_stats() > > Of these, only ath11k_dp_rx_mon_mpdu_pop() has non-trivial stack > usage, so mark that function as 'noinline_for_stack' to prevent it > from being inlined in ath11k_dp_rx_process_mon_status(), thereby > eliminating the excessive stack usage. > > Link: https://msgid.link/bc214795-1c51-4cb7-922f-67d6ef98bff2@quicinc.com # [1] > Link: https://patch.msgid.link/20241028-ath12k_qmi_driver_event_work-v1-1-0d532eb593fa@quicinc.com # [2] > Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com> Acked-by: Kalle Valo <kvalo@kernel.org>
diff --git a/drivers/net/wireless/ath/ath11k/dp_rx.c b/drivers/net/wireless/ath/ath11k/dp_rx.c index 40088e62572e..f253fac116bc 100644 --- a/drivers/net/wireless/ath/ath11k/dp_rx.c +++ b/drivers/net/wireless/ath/ath11k/dp_rx.c @@ -4690,11 +4690,12 @@ static void ath11k_dp_mon_get_buf_len(struct hal_rx_msdu_desc_info *info, } } -static u32 -ath11k_dp_rx_mon_mpdu_pop(struct ath11k *ar, int mac_id, - void *ring_entry, struct sk_buff **head_msdu, - struct sk_buff **tail_msdu, u32 *npackets, - u32 *ppdu_id) +/* clang stack usage explodes if this is inlined */ +static noinline_for_stack +u32 ath11k_dp_rx_mon_mpdu_pop(struct ath11k *ar, int mac_id, + void *ring_entry, struct sk_buff **head_msdu, + struct sk_buff **tail_msdu, u32 *npackets, + u32 *ppdu_id) { struct ath11k_pdev_dp *dp = &ar->dp; struct ath11k_mon_data *pmon = (struct ath11k_mon_data *)&dp->mon_data;
When compiling the ath11k driver using clang with KASAN enabled, the following warning is observed: drivers/net/wireless/ath/ath11k/dp_rx.c:5244:5: warning: stack frame size (1304) exceeds limit (1024) in 'ath11k_dp_rx_process_mon_status' [-Wframe-larger-than] This is similar to the issue found in ath12k/qmi.c that was discussed in [1] and fixed with [2]. The issue is that clang inlining can explode stack usage. ath11k_dp_rx_process_mon_status() itself is a pretty lightweight function, but it dispatches to several other functions which do the real work: ath11k_dp_rx_process_mon_status() ath11k_dp_rx_reap_mon_status_ring() ath11k_dp_rx_mon_dest_process() ath11k_dp_rx_mon_mpdu_pop() * ath11k_dp_rx_mon_deliver() ath11k_dp_rx_mon_merg_msdus() ath11k_dp_rx_deliver_msdu() ath11k_dp_rx_update_peer_stats() Of these, only ath11k_dp_rx_mon_mpdu_pop() has non-trivial stack usage, so mark that function as 'noinline_for_stack' to prevent it from being inlined in ath11k_dp_rx_process_mon_status(), thereby eliminating the excessive stack usage. Link: https://msgid.link/bc214795-1c51-4cb7-922f-67d6ef98bff2@quicinc.com # [1] Link: https://patch.msgid.link/20241028-ath12k_qmi_driver_event_work-v1-1-0d532eb593fa@quicinc.com # [2] Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com> --- drivers/net/wireless/ath/ath11k/dp_rx.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-)