[ath9k-devel] ath9k causes lockups since kernel 2.6.35

[Tony Houghton <h@realh.co.uk>]

On Sun, 5 Jun 2011 07:30:34 -0400
Camilo Mesias <camilo@mesias.co.uk> wrote:

> I have a suspicion the lockup happens in the rf off code, because I
> can cause the lockup reliably simply with iwconfig wlan0 tx off
> Can other people confirm this? Is it worth putting more defensive
> code in that function?

This is what I found (I forgot to use Reply To All so I only sent this
to Mohammed Shafi before):

: The freeze is in ath9k_hw_set_power_awake during the for() loop when it
: calls
: REG_SET_BIT(ah, AR_RTC_FORCE_WAKE, AR_RTC_FORCE_WAKE_EN);

That could be wrong because I used printk to track it down and there may
be a race condition between the crash and the messages appearing on the
console.

I also discovered that
  val = REG_READ(ah, AR_RTC_STATUS) & AR_RTC_STATUS_M;
had a result of 15, but the status should only have one bit set at a
time I think?

I also wondered why it was trying to go into a wake state when it was
supposed to be shutting down.