| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Wed, 16 Jan 2008 23:24:21 +0100
From: Andi Kleen <ak@...e.de>
To: linux-kernel@...r.kernel.org, linux-mm@...ck.org
Subject: [PATCH] Only print kernel debug information for OOMs caused by kernel allocations
I recently suffered an 20+ minutes oom thrash disk to death and computer
completely unresponsive situation on my desktop when some user program
decided to grab all memory. It eventually recovered, but left lots
of ugly and imho misleading messages in the kernel log. here's a minor
improvement
-Andi
---
Only print kernel debug information for OOMs caused by kernel allocations
For any page cache allocation don't print the backtrace and the detailed
zone debugging information. This makes the problem look less like
a kernel bug because it typically isn't.
I needed a new task flag for that. Since the bits are running low
I reused an unused one (PF_STARTING)
Also clarify the error message (OOM means nothing to a normal user)
Signed-off-by: Andi Kleen <ak@...e.de>
---
include/linux/pagemap.h | 7 -------
include/linux/sched.h | 2 +-
mm/filemap.c | 16 +++++++++++-----
mm/oom_kill.c | 9 ++++++---
4 files changed, 18 insertions(+), 16 deletions(-)
Index: linux/include/linux/sched.h
===================================================================
--- linux.orig/include/linux/sched.h
+++ linux/include/linux/sched.h
@@ -1358,7 +1358,7 @@ static inline void put_task_struct(struc
*/
#define PF_ALIGNWARN 0x00000001 /* Print alignment warning msgs */
/* Not implemented yet, only for 486*/
-#define PF_STARTING 0x00000002 /* being created */
+#define PF_USER_ALLOC 0x00000002 /* Current allocation is user initiated */
#define PF_EXITING 0x00000004 /* getting shut down */
#define PF_EXITPIDONE 0x00000008 /* pi exit done on shut down */
#define PF_VCPU 0x00000010 /* I'm a virtual CPU */
Index: linux/mm/oom_kill.c
===================================================================
--- linux.orig/mm/oom_kill.c
+++ linux/mm/oom_kill.c
@@ -340,11 +340,14 @@ static int oom_kill_process(struct task_
struct task_struct *c;
if (printk_ratelimit()) {
- printk(KERN_WARNING "%s invoked oom-killer: "
+ printk(KERN_WARNING "%s ran out of available memory: "
"gfp_mask=0x%x, order=%d, oomkilladj=%d\n",
current->comm, gfp_mask, order, current->oomkilladj);
- dump_stack();
- show_mem();
+ /* Only dump backtrace for kernel initiated allocations */
+ if (!(p->flags & PF_USER_ALLOC)) {
+ dump_stack();
+ show_mem();
+ }
}
/*
Index: linux/include/linux/pagemap.h
===================================================================
--- linux.orig/include/linux/pagemap.h
+++ linux/include/linux/pagemap.h
@@ -62,14 +62,7 @@ static inline void mapping_set_gfp_mask(
#define page_cache_release(page) put_page(page)
void release_pages(struct page **pages, int nr, int cold);
-#ifdef CONFIG_NUMA
extern struct page *__page_cache_alloc(gfp_t gfp);
-#else
-static inline struct page *__page_cache_alloc(gfp_t gfp)
-{
- return alloc_pages(gfp, 0);
-}
-#endif
static inline struct page *page_cache_alloc(struct address_space *x)
{
Index: linux/mm/filemap.c
===================================================================
--- linux.orig/mm/filemap.c
+++ linux/mm/filemap.c
@@ -482,17 +482,23 @@ int add_to_page_cache_lru(struct page *p
return ret;
}
-#ifdef CONFIG_NUMA
struct page *__page_cache_alloc(gfp_t gfp)
{
+ struct task_struct *me = current;
+ unsigned old = (~me->flags) & PF_USER_ALLOC;
+ struct page *p;
+
+ me->flags |= PF_USER_ALLOC;
if (cpuset_do_page_mem_spread()) {
int n = cpuset_mem_spread_node();
- return alloc_pages_node(n, gfp, 0);
- }
- return alloc_pages(gfp, 0);
+ p = alloc_pages_node(n, gfp, 0);
+ } else
+ p = alloc_pages(gfp, 0);
+ /* Clear USER_ALLOC if it wasn't set originally */
+ me->flags ^= old;
+ return p;
}
EXPORT_SYMBOL(__page_cache_alloc);
-#endif
static int __sleep_on_page_lock(void *word)
{
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists