Commit 65d2f0bc authored by Andi Kleen's avatar Andi Kleen Committed by Linus Torvalds

x86: Always flush pages in change_page_attr

Fix a bug introduced with the CLFLUSH changes: we must always flush pages
changed in cpa(), not just when they are reverted.

Reenable CLFLUSH usage with that now (it was temporarily disabled
for .22)

Add some BUG_ONs

Contains fixes from  Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Signed-off-by: default avatarAndi Kleen <ak@suse.de>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent ad386589
......@@ -82,7 +82,7 @@ static void flush_kernel_map(void *arg)
struct page *p;
/* High level code is not ready for clflush yet */
if (0 && cpu_has_clflush) {
if (cpu_has_clflush) {
list_for_each_entry (p, lh, lru)
cache_flush_page(p);
} else if (boot_cpu_data.x86_model >= 4)
......@@ -136,6 +136,12 @@ static inline void revert_page(struct page *kpte_page, unsigned long address)
ref_prot));
}
static inline void save_page(struct page *kpte_page)
{
if (!test_and_set_bit(PG_arch_1, &kpte_page->flags))
list_add(&kpte_page->lru, &df_list);
}
static int
__change_page_attr(struct page *page, pgprot_t prot)
{
......@@ -150,6 +156,9 @@ __change_page_attr(struct page *page, pgprot_t prot)
if (!kpte)
return -EINVAL;
kpte_page = virt_to_page(kpte);
BUG_ON(PageLRU(kpte_page));
BUG_ON(PageCompound(kpte_page));
if (pgprot_val(prot) != pgprot_val(PAGE_KERNEL)) {
if (!pte_huge(*kpte)) {
set_pte_atomic(kpte, mk_pte(page, prot));
......@@ -179,11 +188,11 @@ __change_page_attr(struct page *page, pgprot_t prot)
* time (not via split_large_page) and in turn we must not
* replace it with a largepage.
*/
save_page(kpte_page);
if (!PageReserved(kpte_page)) {
if (cpu_has_pse && (page_private(kpte_page) == 0)) {
ClearPagePrivate(kpte_page);
paravirt_release_pt(page_to_pfn(kpte_page));
list_add(&kpte_page->lru, &df_list);
revert_page(kpte_page, address);
}
}
......@@ -236,6 +245,11 @@ void global_flush_tlb(void)
spin_unlock_irq(&cpa_lock);
flush_map(&l);
list_for_each_entry_safe(pg, next, &l, lru) {
list_del(&pg->lru);
clear_bit(PG_arch_1, &pg->flags);
if (PageReserved(pg) || !cpu_has_pse || page_private(pg) != 0)
continue;
ClearPagePrivate(pg);
__free_page(pg);
}
}
......
......@@ -74,13 +74,11 @@ static void flush_kernel_map(void *arg)
struct page *pg;
/* When clflush is available always use it because it is
much cheaper than WBINVD. Disable clflush for now because
the high level code is not ready yet */
if (1 || !cpu_has_clflush)
much cheaper than WBINVD. */
if (!cpu_has_clflush)
asm volatile("wbinvd" ::: "memory");
else list_for_each_entry(pg, l, lru) {
void *adr = page_address(pg);
if (cpu_has_clflush)
cache_flush_page(adr);
}
__flush_tlb_all();
......@@ -95,6 +93,7 @@ static LIST_HEAD(deferred_pages); /* protected by init_mm.mmap_sem */
static inline void save_page(struct page *fpage)
{
if (!test_and_set_bit(PG_arch_1, &fpage->flags))
list_add(&fpage->lru, &deferred_pages);
}
......@@ -129,9 +128,12 @@ __change_page_attr(unsigned long address, unsigned long pfn, pgprot_t prot,
pte_t *kpte;
struct page *kpte_page;
pgprot_t ref_prot2;
kpte = lookup_address(address);
if (!kpte) return 0;
kpte_page = virt_to_page(((unsigned long)kpte) & PAGE_MASK);
BUG_ON(PageLRU(kpte_page));
BUG_ON(PageCompound(kpte_page));
if (pgprot_val(prot) != pgprot_val(ref_prot)) {
if (!pte_huge(*kpte)) {
set_pte(kpte, pfn_pte(pfn, prot));
......@@ -159,10 +161,9 @@ __change_page_attr(unsigned long address, unsigned long pfn, pgprot_t prot,
/* on x86-64 the direct mapping set at boot is not using 4k pages */
BUG_ON(PageReserved(kpte_page));
if (page_private(kpte_page) == 0) {
save_page(kpte_page);
if (page_private(kpte_page) == 0)
revert_page(address, ref_prot);
}
return 0;
}
......@@ -234,6 +235,10 @@ void global_flush_tlb(void)
flush_map(&l);
list_for_each_entry_safe(pg, next, &l, lru) {
list_del(&pg->lru);
clear_bit(PG_arch_1, &pg->flags);
if (page_private(pg) != 0)
continue;
ClearPagePrivate(pg);
__free_page(pg);
}
......
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