linux-kernel - Re: USB device cannot be reconnected and khubd "blocked for more than 120 seconds"

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]

Message-ID: <CACVXFVMi2nrPT8F08xb5ZG0wzq326oqW7xOqo+_8AOvPSWMvoA@mail.gmail.com>
Date:	Wed, 16 Jan 2013 11:05:22 +0800
From:	Ming Lei <ming.lei@...onical.com>
To:	Linus Torvalds <torvalds@...ux-foundation.org>
Cc:	Tejun Heo <tj@...nel.org>, Alex Riesen <raa.lkml@...il.com>,
	Alan Stern <stern@...land.harvard.edu>,
	Jens Axboe <axboe@...nel.dk>,
	USB list <linux-usb@...r.kernel.org>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: Re: USB device cannot be reconnected and khubd "blocked for more than
 120 seconds"

On Wed, Jan 16, 2013 at 1:36 AM, Linus Torvalds
<torvalds@...ux-foundation.org> wrote:
>
> Because it's not just sd.c that uses async_schedule(), and would need
> the async synchronize. It's floppy.c, it's generic scsi scanning (so
> scsi tapes etc), and it's libata-core.c.

As discussed previously, only the module which will populate device
node for user space inside async func may require the synchronization,
so that the below

                modprobe A
                mount /dev/XXX /mnt

script can't be broken, and that should be the original bug report:

           https://bugzilla.kernel.org/attachment.cgi?id=20937

For other modules, looks the synchonization isn't needed, at least there
are lots of other async(work, kthread, ...) things which is scheduled in
driver probe() and no any synchronize is added after the module init()
completes inside loading module. Do we need to add that sync
for all async things inside loading module?

So looks only sd.c and floppy.c are to be synchronized suppose
some sync interfaces are introduced, doesn't it?


Thanks
--
Ming Lei
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/