From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir@xensource.com>
Subject: Re: [PATCH][PVFB][LINUX] Fix possible sleep while
	holding spinlock
Date: Fri, 15 Dec 2006 18:06:13 +0000
Message-ID: <C1A89495.6290%keir@xensource.com>
References: <87zm9pt8qm.fsf@pike.pond.sub.org>
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To: Markus Armbruster <armbru@redhat.com>, Keir Fraser <keir@xensource.com>
Cc: Atsushi SAKAI <sakaia@jp.fujitsu.com>, xen-devel@lists.xensource.com, xen-ia64-devel@lists.xensource.com
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On 15/12/06 16:38, "Markus Armbruster" <armbru@redhat.com> wrote:

> This patch fixes the locking, but leaves open a race between
> xenfb_update_screen() and do_no_page().  See the source code for a
> detailed explanation of how it works, and where it fails.

That's a bit of a shame. Is there any way we could use do_file_page() and
have a populate hook (which gets to install the PTE itself)? Or are there
lots of assumptions about VMAs that would take this path, assert
VM_NONLINEAR, etc?

 -- Keir