Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, vm86: fix preemption bug
  x86, olpc: fix model detection without OFW
  x86, hpet: fix for LS21 + HPET = boot hang
  x86: CPA avoid repeated lazy mmu flush
  x86: warn if arch_flush_lazy_mmu_cpu is called in preemptible context
  x86/paravirt: make arch_flush_lazy_mmu/cpu disable preemption
  x86, pat: fix warn_on_once() while mapping 0-1MB range with /dev/mem
  x86/cpa: make sure cpa is safe to call in lazy mmu mode
  x86, ptrace, mm: fix double-free on race

1 files changed, 14 insertions, 1 deletions

diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c
index 84ba74820ad..8ca0d8566fc 100644
--- a/arch/x86/mm/pageattr.c
+++ b/arch/x86/mm/pageattr.c
@@ -575,7 +575,6 @@ static int __change_page_attr(struct cpa_data *cpa, int primary)
 		address = cpa->vaddr[cpa->curpage];
 	else
 		address = *cpa->vaddr;
-
 repeat:
 	kpte = lookup_address(address, &level);
 	if (!kpte)
@@ -812,6 +811,13 @@ static int change_page_attr_set_clr(unsigned long *addr, int numpages,
 
 	vm_unmap_aliases();
 
+	/*
+	 * If we're called with lazy mmu updates enabled, the
+	 * in-memory pte state may be stale.  Flush pending updates to
+	 * bring them up to date.
+	 */
+	arch_flush_lazy_mmu_mode();
+
 	cpa.vaddr = addr;
 	cpa.numpages = numpages;
 	cpa.mask_set = mask_set;
@@ -854,6 +860,13 @@ static int change_page_attr_set_clr(unsigned long *addr, int numpages,
 	} else
 		cpa_flush_all(cache);
 
+	/*
+	 * If we've been called with lazy mmu updates enabled, then
+	 * make sure that everything gets flushed out before we
+	 * return.
+	 */
+	arch_flush_lazy_mmu_mode();
+
 out:
 	return ret;
 }