[PATCH] wifi: ath9k: Don't mark channelmap stack variable read-only in ath9k_mci_update_wlan_channels()
This partially reverts commit e161d4b60ae3a5356e07202e0bfedb5fad82c6aa.
Turns out the channelmap variable is not actually read-only, it's modified through the MCI_GPM_CLR_CHANNEL_BIT() macro further down in the function, so making it read-only causes page faults when that code is hit.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=217183 Fixes: e161d4b60ae3 ("wifi: ath9k: Make arrays prof_prio and channelmap static const") Cc: stable@vger.kernel.org Signed-off-by: Toke Høiland-Jørgensen toke@toke.dk --- drivers/net/wireless/ath/ath9k/mci.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/drivers/net/wireless/ath/ath9k/mci.c b/drivers/net/wireless/ath/ath9k/mci.c index 3363fc4e8966..a0845002d6fe 100644 --- a/drivers/net/wireless/ath/ath9k/mci.c +++ b/drivers/net/wireless/ath/ath9k/mci.c @@ -646,9 +646,7 @@ void ath9k_mci_update_wlan_channels(struct ath_softc *sc, bool allow_all) struct ath_hw *ah = sc->sc_ah; struct ath9k_hw_mci *mci = &ah->btcoex_hw.mci; struct ath9k_channel *chan = ah->curchan; - static const u32 channelmap[] = { - 0x00000000, 0xffff0000, 0xffffffff, 0x7fffffff - }; + u32 channelmap[] = {0x00000000, 0xffff0000, 0xffffffff, 0x7fffffff}; int i; s16 chan_start, chan_end; u16 wlan_chan;
Toke Høiland-Jørgensen toke@toke.dk writes:
This partially reverts commit e161d4b60ae3a5356e07202e0bfedb5fad82c6aa.
Turns out the channelmap variable is not actually read-only, it's modified through the MCI_GPM_CLR_CHANNEL_BIT() macro further down in the function, so making it read-only causes page faults when that code is hit.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=217183 Fixes: e161d4b60ae3 ("wifi: ath9k: Make arrays prof_prio and channelmap static const") Cc: stable@vger.kernel.org Signed-off-by: Toke Høiland-Jørgensen toke@toke.dk
I guess the casting in MCI_GPM_CLR_CHANNEL_BIT() hide this and made it impossible for the compiler to detect it? A perfect example why I hate casting :)
Kalle Valo kvalo@kernel.org writes:
Toke Høiland-Jørgensen toke@toke.dk writes:
This partially reverts commit e161d4b60ae3a5356e07202e0bfedb5fad82c6aa.
Turns out the channelmap variable is not actually read-only, it's modified through the MCI_GPM_CLR_CHANNEL_BIT() macro further down in the function, so making it read-only causes page faults when that code is hit.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=217183 Fixes: e161d4b60ae3 ("wifi: ath9k: Make arrays prof_prio and channelmap static const") Cc: stable@vger.kernel.org Signed-off-by: Toke Høiland-Jørgensen toke@toke.dk
I guess the casting in MCI_GPM_CLR_CHANNEL_BIT() hide this and made it impossible for the compiler to detect it? A perfect example why I hate casting :)
Yup, exactly. I was also assuming the compiler would catch it, but yay, C! :/
Anyway, cf the bugzilla this was a pretty bad regression for 6.2, so would be good to move this along reasonably quickly (although I guess we just missed the -net PR for rc7)...
-Toke
Toke Høiland-Jørgensen toke@toke.dk wrote:
This partially reverts commit e161d4b60ae3a5356e07202e0bfedb5fad82c6aa.
Turns out the channelmap variable is not actually read-only, it's modified through the MCI_GPM_CLR_CHANNEL_BIT() macro further down in the function, so making it read-only causes page faults when that code is hit.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=217183 Fixes: e161d4b60ae3 ("wifi: ath9k: Make arrays prof_prio and channelmap static const") Cc: stable@vger.kernel.org Signed-off-by: Toke Høiland-Jørgensen toke@toke.dk Signed-off-by: Kalle Valo quic_kvalo@quicinc.com
Patch applied to ath-next branch of ath.git, thanks.
b956e3110a79 wifi: ath9k: Don't mark channelmap stack variable read-only in ath9k_mci_update_wlan_channels()
On 19/04/2023 15:24, Kalle Valo wrote:
Toke Høiland-Jørgensen toke@toke.dk wrote:
This partially reverts commit e161d4b60ae3a5356e07202e0bfedb5fad82c6aa.
Turns out the channelmap variable is not actually read-only, it's modified through the MCI_GPM_CLR_CHANNEL_BIT() macro further down in the function, so making it read-only causes page faults when that code is hit.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=217183 Fixes: e161d4b60ae3 ("wifi: ath9k: Make arrays prof_prio and channelmap static const") Cc: stable@vger.kernel.org Signed-off-by: Toke Høiland-Jørgensen toke@toke.dk Signed-off-by: Kalle Valo quic_kvalo@quicinc.com
Patch applied to ath-next branch of ath.git, thanks.
b956e3110a79 wifi: ath9k: Don't mark channelmap stack variable read-only in ath9k_mci_update_wlan_channels()
Thanks. Apologies for the regression. My bad.
linux-stable-mirror@lists.linaro.org
-
Colin King (gmail) -
Kalle Valo -
Toke Høiland-Jørgensen