linux-usb.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Oliver Neukum <oneukum@suse.com>
To: Johan Hovold <johan@kernel.org>, Alan Stern <stern@rowland.harvard.edu>
Cc: Greg KH <greg@kroah.com>,
	syzbot <syzbot+ada0f7d3d9fd2016d927@syzkaller.appspotmail.com>,
	syzkaller-bugs@googlegroups.com,
	USB mailing list <linux-usb@vger.kernel.org>
Subject: Re: [PATCH] USB: core: Make usb_start_wait_urb() interruptible
Date: Tue, 31 Aug 2021 13:02:11 +0200	[thread overview]
Message-ID: <ce5a267e-7d3e-a2ac-fd59-f72029ee5c02@suse.com> (raw)
In-Reply-To: <YS3y14DBrg0+n/iI@hovoldconsulting.com>


On 31.08.21 11:13, Johan Hovold wrote:
> On Mon, Aug 30, 2021 at 10:46:13AM -0400, Alan Stern wrote:
>> Perhaps the stable backport could be delayed for a while (say, one 
>> release cycle).
> That might work.
>
>> Do you have alternative suggestions?  I don't think we want special 
>> interruptible versions of usb_control_msg() and usb_bulk_msg() just for 
>> use by usbfs.
> usbfs could carry a temporary local implementation as the documentation
> for usb_start_wait_urb() currently suggests. I assume we can't limit the
> usbfs timeouts.
Upon further considerations forcing user space to handle signals also
breaks the API, albeit in a more subtle manner. I'd suggest that we use
wait_event_killable_timeout(). And do it the way Alan initially disliked,
that is code a version for use by usbfs.

Thus we'd avoid the issue of having an unkillable process, but we do
not impose a need to handle signals.

    Regards
        Oliver


  parent reply	other threads:[~2021-08-31 11:02 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-08-28 15:52 [syzbot] INFO: task hung in do_proc_bulk syzbot
2021-08-28 18:03 ` Alan Stern
2021-08-28 20:05   ` syzbot
2021-08-29  1:58     ` [PATCH] USB: core: Make usb_start_wait_urb() interruptible Alan Stern
2021-08-30  7:56       ` Johan Hovold
2021-08-30 14:46         ` Alan Stern
2021-08-30 15:11           ` Oliver Neukum
2021-08-30 16:09             ` Alan Stern
2021-08-31  8:52               ` Oliver Neukum
2021-08-31  9:13           ` Johan Hovold
2021-08-31 10:47             ` Oliver Neukum
2021-08-31 11:02             ` Oliver Neukum [this message]
2021-08-31 11:10             ` Johan Hovold
2021-08-31 17:03               ` Alan Stern
2021-09-01  8:16                 ` Oliver Neukum
2021-09-02 20:04 ` [syzbot] INFO: task hung in do_proc_bulk Alan Stern
2021-09-02 20:46   ` syzbot

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=ce5a267e-7d3e-a2ac-fd59-f72029ee5c02@suse.com \
    --to=oneukum@suse.com \
    --cc=greg@kroah.com \
    --cc=johan@kernel.org \
    --cc=linux-usb@vger.kernel.org \
    --cc=stern@rowland.harvard.edu \
    --cc=syzbot+ada0f7d3d9fd2016d927@syzkaller.appspotmail.com \
    --cc=syzkaller-bugs@googlegroups.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).