lkml.org 
[lkml]   [2019]   [Jul]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRe: [PATCH v2 1/2] rt2x00usb: fix rx queue hang
Date
Soeren Moch <smoch@web.de> writes:

> Since commit ed194d136769 ("usb: core: remove local_irq_save() around
> ->complete() handler") the handler rt2x00usb_interrupt_rxdone() is
> not running with interrupts disabled anymore. So this completion handler
> is not guaranteed to run completely before workqueue processing starts
> for the same queue entry.
> Be sure to set all other flags in the entry correctly before marking
> this entry ready for workqueue processing. This way we cannot miss error
> conditions that need to be signalled from the completion handler to the
> worker thread.
> Note that rt2x00usb_work_rxdone() processes all available entries, not
> only such for which queue_work() was called.
>
> This patch is similar to what commit df71c9cfceea ("rt2x00: fix order
> of entry flags modification") did for TX processing.
>
> This fixes a regression on a RT5370 based wifi stick in AP mode, which
> suddenly stopped data transmission after some period of heavy load. Also
> stopping the hanging hostapd resulted in the error message "ieee80211
> phy0: rt2x00queue_flush_queue: Warning - Queue 14 failed to flush".
> Other operation modes are probably affected as well, this just was
> the used testcase.
>
> Fixes: ed194d136769 ("usb: core: remove local_irq_save() around ->complete() handler")
> Cc: stable@vger.kernel.org # 4.20+
> Signed-off-by: Soeren Moch <smoch@web.de>

I'll queue this for v5.3.

--
Kalle Valo

\
 
 \ /
  Last update: 2019-07-15 10:51    [W:0.068 / U:10.292 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site