drm: make sure page protections are updated after changing vm_flags
drm: make sure page protections are updated after changing vm_flags

Some architectures compute ->vm_page_prot depending on ->vm_flags, so we
need to update the protections after adjusting the flags.

AFAIK this only affects running X under Xen; without this patch you get
lots of coloured blobs on the screen, or maybe a complete lockup.  Or
anything really.

But that still depends on lots of out-of-tree stuff, so I don't think
there are any consequences for anyone else.  But it is wrong in principle.

Reported-by: Jan Beulich <051346888327db48cce19d2cfd0e1c700bb7cf16@novell.com>
Signed-off-by: Jeremy Fitzhardinge <35cfe9f678a9e9bbdcf2f6e68cd105ce06d149b1@citrix.com>
Signed-off-by: Andrew Morton <5c1e68b099950c134891f0b6e179498a8ebe9cf9@linux-foundation.org>
Signed-off-by: Dave Airlie <f2295d84e358395675bc8031be58672073ae065e@redhat.com>

TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas