[PATCH] swsusp: do not use memcpy for snapshotting memory
swsusp should not use memcpy for snapshotting memory, because on some
architectures memcpy may increase preempt_count (i386 does this when
CONFIG_X86_USE_3DNOW is set). Then, as a result, wrong value of preempt_count
is stored in the image.
Replace memcpy in copy_data_pages with an open-coded loop.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index 24c96f3..75d4886 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -227,11 +227,17 @@
for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) {
if (saveable(zone, &zone_pfn)) {
struct page *page;
+ long *src, *dst;
+ int n;
+
page = pfn_to_page(zone_pfn + zone->zone_start_pfn);
BUG_ON(!pbe);
pbe->orig_address = (unsigned long)page_address(page);
- /* copy_page is not usable for copying task structs. */
- memcpy((void *)pbe->address, (void *)pbe->orig_address, PAGE_SIZE);
+ /* copy_page and memcpy are not usable for copying task structs. */
+ dst = (long *)pbe->address;
+ src = (long *)pbe->orig_address;
+ for (n = PAGE_SIZE / sizeof(long); n; n--)
+ *dst++ = *src++;
pbe = pbe->next;
}
}