I know nothing of VM, but put_page on a page on the LRU list hits a
BUG() inside __free_pages_ok(). Andrew Morton said this was right.
Name: Unpin page bug fix.
Author: Rusty Russell
Status: Tested on 2.5.20
D: This uses page_cache_release() instead of put_page(), as it might
D: be a pagecache page.
diff -urN -I \$.*\$ --exclude TAGS -X /home/rusty/devel/kernel/kernel-patches/current-dontdiff --minimal linux-2.5.20.1460/kernel/futex.c linux-2.5.20.1460.updated/kernel/futex.c
--- linux-2.5.20.1460/kernel/futex.c Sat May 25 14:35:00 2002
+++ linux-2.5.20.1460.updated/kernel/futex.c Wed Jun 5 21:24:37 2002
@@ -33,6 +33,7 @@
#include <linux/futex.h>
#include <linux/highmem.h>
#include <linux/time.h>
+#include <linux/pagemap.h>
#include <asm/uaccess.h>
/* These mutexes are a very simple counter: the winner is the one who
@@ -69,6 +70,14 @@
return &futex_queues[hash_long(h, FUTEX_HASHBITS)];
}
+static inline void unpin_page(struct page *page)
+{
+ /* Avoid releasing the page which is on the LRU list. I don't
+ know if this is correct, but it stops the BUG() in
+ __free_pages_ok(). */
+ page_cache_release(page);
+}
+
static int futex_wake(struct list_head *head,
struct page *page,
unsigned int offset,
@@ -218,7 +227,7 @@
default:
ret = -EINVAL;
}
- put_page(page);
+ unpin_page(page);
return ret;
}
-- Anyone who quotes me in their sig is an idiot. -- Rusty Russell. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
This archive was generated by hypermail 2b29 : Fri Jun 07 2002 - 22:00:27 EST