RE: [12/74] staging: usbip: bugfixes related to kthread conversion

From: Arjan Mels
Date: Mon Apr 18 2011 - 05:20:36 EST


I agree that the bugfix will do no harm on older versions. I have however not seen this particular deadlock occurring on versions before the kthread conversion: the thread termination works differently here (not by polling), so the fix is probably not necessary on older versions.

Apologies for not responding to this before: these were my first patches and I had not realized bugfixes would also be backported to older versions.

Best Regards,

Arjan Mels

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Arjan Mels
Principal Engineer
Device Physics / Wafer Technology and Foundry Organization (WT&FO) / Operations

NXP Semiconductors
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E-mail : arjan.mels@xxxxxxx
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-----Original Message-----
From: Greg KH [mailto:gregkh@xxxxxxx]
Sent: Monday, April 18, 2011 08:03
To: Arnd Bergmann
Cc: linux-kernel@xxxxxxxxxxxxxxx; stable@xxxxxxxxxx; stable-review@xxxxxxxxxx; torvalds@xxxxxxxxxxxxxxxxxxxx; akpm@xxxxxxxxxxxxxxxxxxxx; alan@xxxxxxxxxxxxxxxxxxx; Arjan Mels; Takahiro Hirofuchi; Max Vozeler
Subject: Re: [12/74] staging: usbip: bugfixes related to kthread conversion

On Sun, Apr 17, 2011 at 10:15:01PM +0200, Arnd Bergmann wrote:
> On Wednesday 13 April 2011, Greg KH wrote:
> > From: Arjan Mels <arjan.mels@xxxxxxx>
> >
> > commit d2dd0b07c3e725d386d20294ec906f7ddef207fa upstream.
> >
> > When doing a usb port reset do a queued reset instead to prevent a
> > deadlock: the reset will cause the driver to unbind, causing the
> > usb_driver_lock_for_reset to stall.
> >
> > Signed-off-by: Arjan Mels <arjan.mels@xxxxxxx>
> > Cc: Takahiro Hirofuchi <hirofuchi@xxxxxxxxxxxxxxxxxxxxx>
> > Cc: Max Vozeler <max@xxxxxxxxxxx>
> > Cc: Arnd Bergmann <arnd@xxxxxxxx>
> > Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>
> >
>
> I think either the subject line is misleading or the patch is not
> needed in -stable. The kthread conversion was done in 2.6.38, so
> any bug introduced by it would not need to be fixed in an earlier
> version, afaict.

Yes, the Subject: was incorrect, and I only realized it after it was
committed to the tree, sorry.

The bug fixes were still real.

thanks,

greg k-h
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