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| author | Wei Liu <wei.liu2@citrix.com> | 2014-03-15 16:11:47 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-04-03 12:02:35 -0700 |
| commit | a0a7b1fa22feddc90b25f12aca70bf29a548031e (patch) | |
| tree | b5c56c15eb7a1eb911d546bba8b4a06366cd357f /tools/perf/util/scripting-engines/trace-event-python.c | |
| parent | 7bad2a982359394a7d5fd5c7462b75d4d3ae95fc (diff) | |
xen/balloon: flush persistent kmaps in correct position
commit 09ed3d5ba06137913960f9c9385f71fc384193ab upstream.
Xen balloon driver will update ballooned out pages' P2M entries to point
to scratch page for PV guests. In 24f69373e2 ("xen/balloon: don't alloc
page while non-preemptible", kmap_flush_unused was moved after updating
P2M table. In that case for 32 bit PV guest we might end up with
P2M X -----> S (S is mfn of balloon scratch page)
M2P Y -----> X (Y is mfn in persistent kmap entry)
kmap_flush_unused() iterates through all the PTEs in the kmap address
space, using pte_to_page() to obtain the page. If the p2m and the m2p
are inconsistent the incorrect page is returned. This will clear
page->address on the wrong page which may cause subsequent oopses if
that page is currently kmap'ed.
Move the flush back between get_page and __set_phys_to_machine to fix
this.
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'tools/perf/util/scripting-engines/trace-event-python.c')
0 files changed, 0 insertions, 0 deletions