From: Oliver Neukum <oliver@neukum.org>
Organization: Novell
To: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] usb/mcs7830: Don't use buffers from stack for USB transfers
Date: Wed, 21 Jan 2009 00:36:49 +0100
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Am Wednesday 21 January 2009 00:23:45 schrieb David Miller:
> > GFP_NOIO seems out of place in a network driver: there is nothing
> > wrong with waiting for I/O here, so plain GFP_KERNEL should be fine.
> 
> There seems to be a large precendence for this in other USB drivers,
> both for networking and storage. ?Probably a mutex or other locking
> hierarchy issue.

Usb storage uses a lot of infrastructure in error handling. As a storage
interface and another interface can share a device and be reset only
together. All drivers' reset handling must be written as if they were
block devices. Therefore you see a lot of GFP_NOIO in USB.

	Regards
		Oliver

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