From mboxrd@z Thu Jan 1 00:00:00 1970 From: Johannes Berg Subject: Re: [Bug #13337] [post 2.6.29 regression] hang during suspend of b44/b43 modules Date: Sat, 11 Jul 2009 19:47:44 +0200 Message-ID: <1247334464.30647.109.camel@johannes.local> References: <87k52izvd9.fsf@scholz.fias.uni-frankfurt.de> <87y6qxx50z.fsf@scholz.fias.uni-frankfurt.de> <200907092203.10294.rjw@sisk.pl> <1247171295.1905.5.camel@johannes.local> <87prc78ga9.fsf@scholz.fias.uni-frankfurt.de> <1247322985.30647.108.camel@johannes.local> <8763dznnki.fsf@scholz.fias.uni-frankfurt.de> Mime-Version: 1.0 Content-Type: multipart/signed; micalg="pgp-sha1"; protocol="application/pgp-signature"; boundary="=-1KOfra4iopVe4GXK2l1w" Return-path: In-Reply-To: <8763dznnki.fsf-X87fCqEI3snt2/fatF9ZgSk+o5UQzIjPIRYYPiSvRdM@public.gmane.org> Sender: kernel-testers-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: To: Jan Scholz Cc: "Rafael J. Wysocki" , Linux Kernel Mailing List , Kernel Testers List , Tomas Janousek , "John W. Linville" --=-1KOfra4iopVe4GXK2l1w Content-Type: text/plain Content-Transfer-Encoding: quoted-printable On Sat, 2009-07-11 at 19:20 +0200, Jan Scholz wrote: > Johannes Berg writes: >=20 > > On Sat, 2009-07-11 at 16:07 +0200, Jan Scholz wrote: > > > >> > Jan, can you run with console_suspend=3D0 (or whatever it is now, Ra= fael > >> > will correct me if I'm wrong) that should work on your platform, and= put > >> > a bunch of printk calls into __ieee80211_suspend in net/mac80211/pm.= c to > >> > see where in there it's hanging? > >>=20 > >> Did that, seems like it hangs in > >> drv_remove_interface(local, &conf); > > > > Ok, thanks! I was going to suggest doing the same in > > b43_op_remove_interface in drivers/net/wireless/b43/main.c, but I think > > the problem is just that we have an ordering problem and call drv_stop > > before drv_remove_interface. I'll try to come up with a fix soon -- > > might not be able to today though, in the meantime I guess you can just > > move the drv_stop call to the end of the function and tell me if that > > works -- that would be racy but should be ok most of the time. >=20 > I moved drv_stop to the end of the function (see patch below) and now > suspend works fine. Thanks, that's what I suspected -- I'll take a closer look into what is required to make it race-free against RX. johannes > Jan >=20 > diff --git a/net/mac80211/pm.c b/net/mac80211/pm.c > index 7a549f9..0ac15fb 100644 > --- a/net/mac80211/pm.c > +++ b/net/mac80211/pm.c > @@ -58,12 +58,6 @@ int __ieee80211_suspend(struct ieee80211_hw *hw) > /* flush again, in case driver queued work */ > flush_workqueue(local->hw.workqueue); > =20 > - /* stop hardware - this must stop RX */ > - if (local->open_count) { > - ieee80211_led_radio(local, false); > - drv_stop(local); > - } > - > /* remove STAs */ > spin_lock_irqsave(&local->sta_lock, flags); > list_for_each_entry(sta, &local->sta_list, list) { > @@ -111,6 +105,12 @@ int __ieee80211_suspend(struct ieee80211_hw *hw) > drv_remove_interface(local, &conf); > } > =20 > + /* stop hardware - this must stop RX */ > + if (local->open_count) { > + ieee80211_led_radio(local, false); > + drv_stop(local); > + } > + > local->suspended =3D true; > local->quiescing =3D false; >=20 --=-1KOfra4iopVe4GXK2l1w Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- iQIcBAABAgAGBQJKWNA9AAoJEODzc/N7+QmaqvIP/1ZOSyhAGiJeS8bmczgysKD9 tx73CdXCONQV1mF1Ty3FM1Q2zjS5Vl1gv/pzOMixcBcgai50WZL2UoY8KZsaN//x 3FAEextpoUCoJm0v/IZjI5AzW8sAcQttuJVhp5/IMO3a296QPjX6TTS3KPtNn3lu gW+IvFVe+ozjjo6AiL1KrcyGbDiAqCEst/KaN+h78ksQdDu6OhjzDUMpJMehKguF LFztQBIHb4XbW1tlHoXdD4s4v/g4msuqWXyciH5lzVAQNrpF+CtfVnqsLbPWuHRI 5zn0xzjC/NX4WItiZ+If5E1wVNwhwUOqwWouL/8DOx4rjYnXxd24Plq5fV1WbaMH wLG4zJh4QElL5xWESw8ysZX88QAYvMnE45jDj9MFOkEK4Qqf+8WG27Jilkq0SRqX NFLsR2Adzb+SStJiOMJV4yasRw9mULys5P7l+MxWDdjLhgR8AUhUhToKWu2CZEec MsiNtrTlk2M3pil4qCVE66gB3LUYU0PJw+7VjJ6ca2XPB+pBDN/Clkp85PiVC4vo 7TIvqNCqE+0Gw/d6O02MV4Ou7NnNk7UBv1IOxZgLNGT2Ike7xPZ4QG+9QoAVTe82 4XelpBwi6vE820Avl9aSV74STKr1MRHiB1PdtDUJ/eCj4naHM6vSdzXvTUpZkMMn /TVavKEotqpBi4wACCDR =oIz7 -----END PGP SIGNATURE----- --=-1KOfra4iopVe4GXK2l1w--