From mboxrd@z Thu Jan  1 00:00:00 1970
From: Keir Fraser <keir@xensource.com>
Subject: Re: [PATCH] Take a writer lock for mmap_sem.
Date: Mon, 09 Jul 2007 17:18:27 +0100
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On 9/7/07 16:45, "Hollis Blanchard" <hollisb@us.ibm.com> wrote:

> 
> My mistake, I meant to send this separately.
> 
> In 2.6.17, we did our own locking inside direct_remap_pfn_range(). In
> the current Linux tree though, the locking is done in privcmd_ioctl().
> 
> However, since direct_remap_pfn_range() is modifying the mm_struct,
> shouldn't that be a a write lock rather than a read lock?

Ah yes, agreed. All other callers seem to get this implicitly because they
are ->mmap handlers.

 -- Keir