* signal.
*/
static int kill_proc_ao(struct task_struct *t, unsigned long addr, int trapno,
- unsigned long pfn)
+ unsigned long pfn, struct page *page)
{
struct siginfo si;
int ret;
#ifdef __ARCH_SI_TRAPNO
si.si_trapno = trapno;
#endif
- si.si_addr_lsb = PAGE_SHIFT;
+ si.si_addr_lsb = compound_order(compound_head(page)) + PAGE_SHIFT;
/*
* Don't use force here, it's convenient if the signal
* can be temporarily blocked.
int nr;
do {
nr = shrink_slab(1000, GFP_KERNEL, 1000);
- if (page_count(p) == 0)
+ if (page_count(p) == 1)
break;
} while (nr > 10);
}
* wrong earlier.
*/
static void kill_procs_ao(struct list_head *to_kill, int doit, int trapno,
- int fail, unsigned long pfn)
+ int fail, struct page *page, unsigned long pfn)
{
struct to_kill *tk, *next;
* process anyways.
*/
else if (kill_proc_ao(tk->tsk, tk->addr, trapno,
- pfn) < 0)
+ pfn, page) < 0)
printk(KERN_ERR
"MCE %#lx: Cannot send advisory machine check signal to %s:%d\n",
pfn, tk->tsk->comm, tk->tsk->pid);
* Issues:
* - Error on hugepage is contained in hugepage unit (not in raw page unit.)
* To narrow down kill region to one page, we need to break up pmd.
- * - To support soft-offlining for hugepage, we need to support hugepage
- * migration.
*/
static int me_huge_page(struct page *p, unsigned long pfn)
{
+ int res = 0;
struct page *hpage = compound_head(p);
/*
* We can safely recover from error on free or reserved (i.e.
* so there is no race between isolation and mapping/unmapping.
*/
if (!(page_mapping(hpage) || PageAnon(hpage))) {
- __isolate_hwpoisoned_huge_page(hpage);
- return RECOVERED;
+ res = dequeue_hwpoisoned_huge_page(hpage);
+ if (!res)
+ return RECOVERED;
}
return DELAYED;
}
* any accesses to the poisoned memory.
*/
kill_procs_ao(&tokill, !!PageDirty(hpage), trapno,
- ret != SWAP_SUCCESS, pfn);
+ ret != SWAP_SUCCESS, p, pfn);
return ret;
}
* We need/can do nothing about count=0 pages.
* 1) it's a free page, and therefore in safe hand:
* prep_new_page() will be the gate keeper.
- * 2) it's part of a non-compound high order page.
+ * 2) it's a free hugepage, which is also safe:
+ * an affected hugepage will be dequeued from hugepage freelist,
+ * so there's no concern about reusing it ever after.
+ * 3) it's part of a non-compound high order page.
* Implies some kernel user: cannot stop them from
* R/W the page; let's pray that the page has been
* used and will be freed some time later.
if (is_free_buddy_page(p)) {
action_result(pfn, "free buddy", DELAYED);
return 0;
+ } else if (PageHuge(hpage)) {
+ /*
+ * Check "just unpoisoned", "filter hit", and
+ * "race with other subpage."
+ */
+ lock_page_nosync(hpage);
+ if (!PageHWPoison(hpage)
+ || (hwpoison_filter(p) && TestClearPageHWPoison(p))
+ || (p != hpage && TestSetPageHWPoison(hpage))) {
+ atomic_long_sub(nr_pages, &mce_bad_pages);
+ return 0;
+ }
+ set_page_hwpoison_huge_page(hpage);
+ res = dequeue_hwpoisoned_huge_page(hpage);
+ action_result(pfn, "free huge",
+ res ? IGNORED : DELAYED);
+ unlock_page(hpage);
+ return res;
} else {
action_result(pfn, "high order kernel", IGNORED);
return -EBUSY;
nr_pages = 1 << compound_order(page);
if (!get_page_unless_zero(page)) {
+ /*
+ * Since HWPoisoned hugepage should have non-zero refcount,
+ * race between memory failure and unpoison seems to happen.
+ * In such case unpoison fails and memory failure runs
+ * to the end.
+ */
+ if (PageHuge(page)) {
+ pr_debug("MCE: Memory failure is now running on free hugepage %#lx\n", pfn);
+ return 0;
+ }
if (TestClearPageHWPoison(p))
atomic_long_sub(nr_pages, &mce_bad_pages);
pr_debug("MCE: Software-unpoisoned free page %#lx\n", pfn);
static struct page *new_page(struct page *p, unsigned long private, int **x)
{
int nid = page_to_nid(p);
- return alloc_pages_exact_node(nid, GFP_HIGHUSER_MOVABLE, 0);
+ if (PageHuge(p))
+ return alloc_huge_page_node(page_hstate(compound_head(p)),
+ nid);
+ else
+ return alloc_pages_exact_node(nid, GFP_HIGHUSER_MOVABLE, 0);
}
/*
* was free.
*/
set_migratetype_isolate(p);
+ /*
+ * When the target page is a free hugepage, just remove it
+ * from free hugepage list.
+ */
if (!get_page_unless_zero(compound_head(p))) {
- if (is_free_buddy_page(p)) {
+ if (PageHuge(p)) {
+ pr_debug("get_any_page: %#lx free huge page\n", pfn);
+ ret = dequeue_hwpoisoned_huge_page(compound_head(p));
+ } else if (is_free_buddy_page(p)) {
pr_debug("get_any_page: %#lx free buddy page\n", pfn);
/* Set hwpoison bit while page is still isolated */
SetPageHWPoison(p);
return ret;
}
+static int soft_offline_huge_page(struct page *page, int flags)
+{
+ int ret;
+ unsigned long pfn = page_to_pfn(page);
+ struct page *hpage = compound_head(page);
+ LIST_HEAD(pagelist);
+
+ ret = get_any_page(page, pfn, flags);
+ if (ret < 0)
+ return ret;
+ if (ret == 0)
+ goto done;
+
+ if (PageHWPoison(hpage)) {
+ put_page(hpage);
+ pr_debug("soft offline: %#lx hugepage already poisoned\n", pfn);
+ return -EBUSY;
+ }
+
+ /* Keep page count to indicate a given hugepage is isolated. */
+
+ list_add(&hpage->lru, &pagelist);
+ ret = migrate_huge_pages(&pagelist, new_page, MPOL_MF_MOVE_ALL, 0);
+ if (ret) {
+ pr_debug("soft offline: %#lx: migration failed %d, type %lx\n",
+ pfn, ret, page->flags);
+ if (ret > 0)
+ ret = -EIO;
+ return ret;
+ }
+done:
+ if (!PageHWPoison(hpage))
+ atomic_long_add(1 << compound_order(hpage), &mce_bad_pages);
+ set_page_hwpoison_huge_page(hpage);
+ dequeue_hwpoisoned_huge_page(hpage);
+ /* keep elevated page count for bad page */
+ return ret;
+}
+
/**
* soft_offline_page - Soft offline a page.
* @page: page to offline
int ret;
unsigned long pfn = page_to_pfn(page);
+ if (PageHuge(page))
+ return soft_offline_huge_page(page, flags);
+
ret = get_any_page(page, pfn, flags);
if (ret < 0)
return ret;
git.openpandora.org / pandora-kernel.git / blobdiff