linux-kernel - Re: btusb "firmware request while host is not available" at resume

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 11 Sep 2017 06:46:47 -0700
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     Marcel Holtmann <marcel@...tmann.org>
Cc:     Linus Torvalds <torvalds@...ux-foundation.org>,
        Gabriel C <nix.or.die@...il.com>,
        "Luis R. Rodriguez" <mcgrof@...nel.org>, Tejun Heo <tj@...nel.org>,
        "Gustavo F. Padovan" <gustavo@...ovan.org>,
        Sukumar Ghorai <sukumar.ghorai@...el.com>,
        "Rafael J. Wysocki" <rjw@...ysocki.net>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        "bluez mailin list (linux-bluetooth@...r.kernel.org)" 
        <linux-bluetooth@...r.kernel.org>
Subject: Re: btusb "firmware request while host is not available" at resume

On Mon, Sep 11, 2017 at 07:12:44AM +0200, Marcel Holtmann wrote:
> Hi Linus,
> 
> >> Yes 81f95076281f is to blame.. After reverting it all is fine again.
> >> 
> >> 15 resume cycles on the one laptop , 10 on the other without to hit the
> >> trace.
> > 
> > Yeah, I think that disable/enable_firmware in the suspend/resume path
> > is basically just completely random code. There  is nothing that
> > serializes with anything else, and it has no actual basis for saying
> > "I am now disabled/enabled" except for some entirely random time of
> > whenever the suspend/resume callbacks happen.
> > 
> > I'm going to revert it.
> > 
> > I wonder why 4.13 seemed to work for me. Or maybe it didn't, and I
> > just didn't notice, because I didn't use bluetooth and I wasn't
> > traveling. I test my laptop every release, but I don't necessarily
> > always _use_ it.
> 
> we have a bug report that might go into the similar direction. So the
> problem is that modern Bluetooth controller require full firmware
> loading (not just ROM patching) and if the controller has the firmware
> somehow already loaded, but then looses power and needs a reload, then
> it is not cached (since it was never requested in the first place).
> 
> Of course if the reload triggers during resume when not file system is
> available, it can not request the firmware. That will just fail and
> thus you might see this issue. We have a few RFC patches on the
> mailing list that I have to review. It is however not that easy all
> the time to find the right firmware file (at least not for Intel
> hardware) since the boot loader provides different information than
> the fully operational firmware. So I need to make sure that request
> the right firmware (if we do not need it initially) so that it gets
> cached.

To confirm, reverting this fixes the problem I was seeing in 4.13.  I've
queued it up for the next 4.13-stable release as well.

thanks,

greg k-h