From: Felipe Balbi <balbi@kernel.org>
To: Al Viro <viro@zeniv.linux.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
Christoph Hellwig <hch@lst.de>,
"linux-usb@vger.kernel.org" <linux-usb@vger.kernel.org>
Subject: Re: [heads-up] deadlock in configfs_symlink()
Date: Mon, 5 Aug 2019 11:18:00 +0300 [thread overview]
Message-ID: <CAH8TKc8kAR2iKETnh5RH1qVUiFUH2BSnirKg_RSbUEZ9ui8FuA@mail.gmail.com> (raw)
In-Reply-To: <20190804204809.GA29474@ZenIV.linux.org.uk>
Hi,
On Sun, Aug 4, 2019 at 11:48 PM Al Viro <viro@zeniv.linux.org.uk> wrote:
>
> On Sun, Aug 04, 2019 at 09:31:43PM +0100, Al Viro wrote:
>
> > FWIW, the following reproduces the deadlock on mainline:
> >
> > dd if=/dev/zero of=/tmp/image bs=1M count=20
> > modprobe dummy_hcd
> > modprobe configfs
> > mount -t configfs none /sys/kernel/config
> > modprobe g_mass_storage file=/tmp/image ro=y
> > cd /sys/kernel/config/usb_gadget/
> > mkdir blah
> > cd blah/configs
> > mkdir foo.1
> > cd foo.1
> > ln -s /sys/kernel/config/usb_gadget/blah/configs/foo.1/no-such-dir/ barf
>
> So does the following, actually - mass_storage is irrelevant here; it just
> brings libcomposite in.
>
> modprobe dummy_hcd
> modprobe libcomposite
> mount -t configfs none /sys/kernel/config
> cd /sys/kernel/config/usb_gadget/
> mkdir blah
> cd blah/configs
> mkdir foo.1
> cd foo.1
> ln -s /sys/kernel/config/usb_gadget/blah/configs/foo.1/no-such-dir/ barf
I'll try to reproduce on my end. Added linux-usb to the loop
--
balbi
parent reply other threads:[~2019-08-05 8:18 UTC|newest]
Thread overview: expand[flat|nested] mbox.gz Atom feed
[parent not found: <20190804204809.GA29474@ZenIV.linux.org.uk>]
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