| Message ID | 20241119-ath11k-noinline-v1-3-4ec0a8aa30b2@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/wow.c:672:5: warning: stack frame size (1336) exceeds limit (1024) in 'ath11k_wow_op_suspend' [-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_wow_op_suspend() itself is a pretty lightweight function, but > it dispatches to several other functions which do the real work. One > path in particular is: > > ath11k_wow_op_suspend() > ath11k_wow_set_wakeups() > ath11k_vif_wow_set_wakeups() > ath11k_wow_convert_8023_to_80211() > > Of these, ath11k_wow_convert_8023_to_80211() has non-trivial stack > usage, so mark it as 'noinline_for_stack' to prevent it from being > inlined in ath11k_wow_op_suspend(), 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/wow.c b/drivers/net/wireless/ath/ath11k/wow.c index 827085a926b2..b6f08755129f 100644 --- a/drivers/net/wireless/ath/ath11k/wow.c +++ b/drivers/net/wireless/ath/ath11k/wow.c @@ -148,8 +148,10 @@ static int ath11k_wow_cleanup(struct ath11k *ar) * 802.11: |4B|dest mac(6B)| 6B |src mac(6B)| 8B |type(2B)| body... | * +--+------------+----+-----------+---------------+-----------+ */ -static void ath11k_wow_convert_8023_to_80211(struct cfg80211_pkt_pattern *new, - const struct cfg80211_pkt_pattern *old) +/* clang stack usage explodes if this is inlined */ +static noinline_for_stack +void ath11k_wow_convert_8023_to_80211(struct cfg80211_pkt_pattern *new, + const struct cfg80211_pkt_pattern *old) { u8 hdr_8023_pattern[ETH_HLEN] = {}; u8 hdr_8023_bit_mask[ETH_HLEN] = {};
When compiling the ath11k driver using clang with KASAN enabled, the following warning is observed: drivers/net/wireless/ath/ath11k/wow.c:672:5: warning: stack frame size (1336) exceeds limit (1024) in 'ath11k_wow_op_suspend' [-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_wow_op_suspend() itself is a pretty lightweight function, but it dispatches to several other functions which do the real work. One path in particular is: ath11k_wow_op_suspend() ath11k_wow_set_wakeups() ath11k_vif_wow_set_wakeups() ath11k_wow_convert_8023_to_80211() Of these, ath11k_wow_convert_8023_to_80211() has non-trivial stack usage, so mark it as 'noinline_for_stack' to prevent it from being inlined in ath11k_wow_op_suspend(), 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/wow.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)