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-rw-r--r--kernel/futex.c28
-rw-r--r--kernel/irq/irqdomain.c12
-rw-r--r--kernel/time/clockevents.c1
3 files changed, 27 insertions, 14 deletions
diff --git a/kernel/futex.c b/kernel/futex.c
index ea87f4d..1614be2 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -314,17 +314,29 @@ again:
#endif
lock_page(page_head);
+
+ /*
+ * If page_head->mapping is NULL, then it cannot be a PageAnon
+ * page; but it might be the ZERO_PAGE or in the gate area or
+ * in a special mapping (all cases which we are happy to fail);
+ * or it may have been a good file page when get_user_pages_fast
+ * found it, but truncated or holepunched or subjected to
+ * invalidate_complete_page2 before we got the page lock (also
+ * cases which we are happy to fail). And we hold a reference,
+ * so refcount care in invalidate_complete_page's remove_mapping
+ * prevents drop_caches from setting mapping to NULL beneath us.
+ *
+ * The case we do have to guard against is when memory pressure made
+ * shmem_writepage move it from filecache to swapcache beneath us:
+ * an unlikely race, but we do need to retry for page_head->mapping.
+ */
if (!page_head->mapping) {
+ int shmem_swizzled = PageSwapCache(page_head);
unlock_page(page_head);
put_page(page_head);
- /*
- * ZERO_PAGE pages don't have a mapping. Avoid a busy loop
- * trying to find one. RW mapping would have COW'd (and thus
- * have a mapping) so this page is RO and won't ever change.
- */
- if ((page_head == ZERO_PAGE(address)))
- return -EFAULT;
- goto again;
+ if (shmem_swizzled)
+ goto again;
+ return -EFAULT;
}
/*
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 200ce83..7ca523b 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -143,11 +143,6 @@ int irq_domain_simple_dt_translate(struct irq_domain *d,
return 0;
}
-struct irq_domain_ops irq_domain_simple_ops = {
- .dt_translate = irq_domain_simple_dt_translate,
-};
-EXPORT_SYMBOL_GPL(irq_domain_simple_ops);
-
/**
* irq_domain_create_simple() - Set up a 'simple' translation range
*/
@@ -182,3 +177,10 @@ void irq_domain_generate_simple(const struct of_device_id *match,
}
EXPORT_SYMBOL_GPL(irq_domain_generate_simple);
#endif /* CONFIG_OF_IRQ */
+
+struct irq_domain_ops irq_domain_simple_ops = {
+#ifdef CONFIG_OF_IRQ
+ .dt_translate = irq_domain_simple_dt_translate,
+#endif /* CONFIG_OF_IRQ */
+};
+EXPORT_SYMBOL_GPL(irq_domain_simple_ops);
diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c
index c4eb71c..1ecd6ba 100644
--- a/kernel/time/clockevents.c
+++ b/kernel/time/clockevents.c
@@ -387,7 +387,6 @@ void clockevents_exchange_device(struct clock_event_device *old,
* released list and do a notify add later.
*/
if (old) {
- old->event_handler = clockevents_handle_noop;
clockevents_set_mode(old, CLOCK_EVT_MODE_UNUSED);
list_del(&old->list);
list_add(&old->list, &clockevents_released);
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