File 5a2fd946-x86-dont-wrongly-trigger-linear-pgt-assertion.patch of Package xen.7673

# Commit e40b0219a8c77741ae48989efb520f4a762a5be3
# Date 2017-12-12 14:27:34 +0100
# Author Jan Beulich <jbeulich@suse.com>
# Committer Jan Beulich <jbeulich@suse.com>
x86: don't wrongly trigger linear page table assertion (2)

_put_final_page_type(), when free_page_type() has exited early to allow
for preemption, should not update the time stamp, as the page continues
to retain the typ which is in the process of being unvalidated. I can't
see why the time stamp update was put on that path in the first place
(albeit it may well have been me who had put it there years ago).

This is part of XSA-240.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Tested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: George Dunlap <george.dunlap.com>

--- a/xen/arch/x86/mm.c
+++ b/xen/arch/x86/mm.c
@@ -2371,9 +2371,6 @@ static int _put_final_page_type(struct p
     {
         ASSERT((page->u.inuse.type_info &
                 (PGT_count_mask|PGT_validated|PGT_partial)) == 1);
-        if ( !(shadow_mode_enabled(page_get_owner(page)) &&
-               (page->count_info & PGC_page_table)) )
-            page_set_tlbflush_timestamp(page);
         wmb();
         page->u.inuse.type_info |= PGT_validated;
     }