On Wed, Oct 18, 2017 at 07:42:12AM +0200, Takashi Iwai wrote: > On Wed, 18 Oct 2017 05:24:16 +0200, > Vinod Koul wrote: > > > > On Tue, Oct 17, 2017 at 07:15:08PM +0200, Takashi Iwai wrote: > > > On Tue, 17 Oct 2017 19:15:08 +0200, > > > Vinod Koul wrote: > > > > > > > > On Tue, Oct 17, 2017 at 04:47:11PM +0200, Takashi Iwai wrote: > > > > > The loop in snd_hdac_bus_parse_capabilities() may go to nirvana when > > > > > it hits an invalid register value read: > > > > > > > > > > BUG: unable to handle kernel paging request at ffffad5dc41f3fff > > > > > IP: pci_azx_readl+0x5/0x10 [snd_hda_intel] > > > > > Call Trace: > > > > > snd_hdac_bus_parse_capabilities+0x3c/0x1f0 [snd_hda_core] > > > > > azx_probe_continue+0x7d5/0x940 [snd_hda_intel] > > > > > ..... > > > > > > > > > > This happened on a new Intel machine, and we need to check the value > > > > > and abort the loop accordingly. > > > > > > > > okay and what machine is the problem here. I have had a similar bug report > > > > from Gfx CI guys on CFL machine. Turns out the BIOS was buggy and we fixed > > > > that up by upgrading the BIOS. > > > > > > Yes, it's a CFL-H. Possibly a buggy BIOS, but the driver still > > > shouldn't crash. > > > > Okay so can you ask them to update BIOS and check. > > > > > > Yes it is a good idea to keep this guard but -1 would mean that HW read is > > > > failing which points to some other issue here > > > > > > Right. > > > > In this case should we send this to stable? I have not seen this crashing > > till now except bad BIOS issue > > People will be getting test hardware now and see the Oops. > We can't guarantee the sane BIOS, and obviously the current code does > crash easily, and yet the code fix is trivial -- a perfect situation > for stable :) Right :), But do make sure to ask for BIOS update on that board. Acked-By: Vinod Koul <vinod.koul@xxxxxxxxx> -- ~Vinod _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
