From: Su Hui <suhui@xxxxxxxxxxxx> [ Upstream commit 52221dfddbbfb5b4e029bb2efe9bb7da33ec1e46 ] There are many same functions like _rtl88e_phy_calculate_bit_shift(), _rtl92c_phy_calculate_bit_shift() and so on. And these functions can cause undefined bitwise shift behavior. Add calculate_bit_shift() to replace them and fix undefined behavior in subsequent patches. Signed-off-by: Su Hui <suhui@xxxxxxxxxxxx> Acked-by: Ping-Ke Shih <pkshih@xxxxxxxxxxx> Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxx> Link: https://msgid.link/20231219065739.1895666-2-suhui@xxxxxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/net/wireless/realtek/rtlwifi/wifi.h | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/net/wireless/realtek/rtlwifi/wifi.h b/drivers/net/wireless/realtek/rtlwifi/wifi.h index 3bdda1c98339..abec9ceabe28 100644 --- a/drivers/net/wireless/realtek/rtlwifi/wifi.h +++ b/drivers/net/wireless/realtek/rtlwifi/wifi.h @@ -3230,4 +3230,11 @@ static inline struct ieee80211_sta *rtl_find_sta(struct ieee80211_hw *hw, return ieee80211_find_sta(mac->vif, mac_addr); } +static inline u32 calculate_bit_shift(u32 bitmask) +{ + if (WARN_ON_ONCE(!bitmask)) + return 0; + + return __ffs(bitmask); +} #endif -- 2.43.0