On Fri, Aug 26, 2011 at 7:22 AM, John W. Linville <linville@xxxxxxxxxxxxx> wrote: > On Wed, Aug 24, 2011 at 06:34:24PM -0700, Thomas Pedersen wrote: >> From: Javier Cardona <javier@xxxxxxxxxxx> >> >> This driver reports transmission status to the upper layer >> (ath5k_tx_frame_completed()) while holding the lock on the transmission >> queue (txq->lock). Under failure conditions, the mesh stack will >> attempt to send PERR messages to the previous sender of the failed >> frame. When that happens the driver will attempt to re-acquire the >> txq->lock lock causing a deadlock. There are two possible fixes for >> this, (1) we could defer the transmission of the PERR frame until the >> lock is released or (2) release the lock before invoking >> ieee80211_tx_status(). The ath9k driver implements the second approach >> (see ath_tx_complete() in ath9k/xmit.c) as well as the rt2x00 and b43 >> drivers. The iwl driver, on the other hand, avoids this problem by >> invoking ieee80211_tx_status_irqsafe() which effectively defers >> processing of transmission feedback status. This last approach is the >> least intrusive is implemented here. >> >> Reported by Pedro Larbig (ASPj) >> --- >> drivers/net/wireless/ath/ath5k/base.c | 2 +- >> 1 files changed, 1 insertions(+), 1 deletions(-) > > Missing Signed-off-by... > Yikes. Also, it looks like ieee80211_tx_status() should not be called from irq context. Will resubmit a v2 with signoff and comment shortly. Thomas -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
