The problem is caused by set_page_owner alloc memory to save stack with
GFP_KERNEL in local_riq disabled.
So, we just can't assume that alloc flags should be same with new page,
let's split it. But in most situation, same is ok, in alloc_pages_bulk,
input GFP_ATOMIC when prep_new_pages
Reported-and-tested-by: [email protected]
Suggested-by: Wang Qing <[email protected]>
Signed-off-by: Yang Huan <[email protected]>
---
include/linux/page_owner.h | 8 ++++----
mm/compaction.c | 2 +-
mm/internal.h | 2 +-
mm/page_alloc.c | 21 +++++++++++----------
mm/page_owner.c | 6 +++---
5 files changed, 20 insertions(+), 19 deletions(-)
diff --git a/include/linux/page_owner.h b/include/linux/page_owner.h
index 3468794f83d2..c930a63e149b 100644
--- a/include/linux/page_owner.h
+++ b/include/linux/page_owner.h
@@ -10,7 +10,7 @@ extern struct page_ext_operations page_owner_ops;
extern void __reset_page_owner(struct page *page, unsigned int order);
extern void __set_page_owner(struct page *page,
- unsigned int order, gfp_t gfp_mask);
+ unsigned int order, gfp_t alloc_gfp, gfp_t page_gfp_mask);
extern void __split_page_owner(struct page *page, unsigned int nr);
extern void __copy_page_owner(struct page *oldpage, struct page *newpage);
extern void __set_page_owner_migrate_reason(struct page *page, int reason);
@@ -25,10 +25,10 @@ static inline void reset_page_owner(struct page *page, unsigned int order)
}
static inline void set_page_owner(struct page *page,
- unsigned int order, gfp_t gfp_mask)
+ unsigned int order, gfp_t alloc_gfp, gfp_t page_gfp_mask)
{
if (static_branch_unlikely(&page_owner_inited))
- __set_page_owner(page, order, gfp_mask);
+ __set_page_owner(page, order, alloc_gfp, page_gfp_mask);
}
static inline void split_page_owner(struct page *page, unsigned int nr)
@@ -56,7 +56,7 @@ static inline void reset_page_owner(struct page *page, unsigned int order)
{
}
static inline void set_page_owner(struct page *page,
- unsigned int order, gfp_t gfp_mask)
+ unsigned int order, gfp_t alloc_gfp, gfp_t page_gfp_mask)
{
}
static inline void split_page_owner(struct page *page,
diff --git a/mm/compaction.c b/mm/compaction.c
index 84fde270ae74..a3bc69dceb1d 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -96,7 +96,7 @@ static void split_map_pages(struct list_head *list)
order = page_private(page);
nr_pages = 1 << order;
- post_alloc_hook(page, order, __GFP_MOVABLE);
+ post_alloc_hook(page, order, __GFP_MOVABLE, __GFP_MOVABLE);
if (order)
split_page(page, order);
diff --git a/mm/internal.h b/mm/internal.h
index e8fdb531f887..9d0cd0840f58 100644
--- a/mm/internal.h
+++ b/mm/internal.h
@@ -195,7 +195,7 @@ extern void memblock_free_pages(struct page *page, unsigned long pfn,
extern void __free_pages_core(struct page *page, unsigned int order);
extern void prep_compound_page(struct page *page, unsigned int order);
extern void post_alloc_hook(struct page *page, unsigned int order,
- gfp_t gfp_flags);
+ gfp_t alloc_gfp, gfp_t page_gfp_mask);
extern int user_min_free_kbytes;
extern void free_unref_page(struct page *page);
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index d1f5de1c1283..bdd057e20376 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -2322,7 +2322,7 @@ static bool check_new_pages(struct page *page, unsigned int order)
}
inline void post_alloc_hook(struct page *page, unsigned int order,
- gfp_t gfp_flags)
+ gfp_t alloc_gfp, gfp_t page_gfp_mask)
{
bool init;
@@ -2344,20 +2344,21 @@ inline void post_alloc_hook(struct page *page, unsigned int order,
* kasan_alloc_pages and kernel_init_free_pages must be
* kept together to avoid discrepancies in behavior.
*/
- init = !want_init_on_free() && want_init_on_alloc(gfp_flags);
+ init = !want_init_on_free() && want_init_on_alloc(page_gfp_mask);
kasan_alloc_pages(page, order, init);
if (init && !kasan_has_integrated_init())
kernel_init_free_pages(page, 1 << order);
- set_page_owner(page, order, gfp_flags);
+ set_page_owner(page, order, alloc_gfp, page_gfp_mask);
}
-static void prep_new_page(struct page *page, unsigned int order, gfp_t gfp_flags,
- unsigned int alloc_flags)
+static void prep_new_page(struct page *page, unsigned int order,
+ gfp_t alloc_gfp, gfp_t page_gfp_mask,
+ unsigned int alloc_flags)
{
- post_alloc_hook(page, order, gfp_flags);
+ post_alloc_hook(page, order, alloc_gfp, page_gfp_mask);
- if (order && (gfp_flags & __GFP_COMP))
+ if (order && (page_gfp_mask & __GFP_COMP))
prep_compound_page(page, order);
/*
@@ -3991,7 +3992,7 @@ get_page_from_freelist(gfp_t gfp_mask, unsigned int order, int alloc_flags,
page = rmqueue(ac->preferred_zoneref->zone, zone, order,
gfp_mask, alloc_flags, ac->migratetype);
if (page) {
- prep_new_page(page, order, gfp_mask, alloc_flags);
+ prep_new_page(page, order, gfp_mask, gfp_mask, alloc_flags);
/*
* If this is a high-order atomic allocation then check
@@ -4211,7 +4212,7 @@ __alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order,
/* Prep a captured page if available */
if (page)
- prep_new_page(page, order, gfp_mask, alloc_flags);
+ prep_new_page(page, order, gfp_mask, gfp_mask, alloc_flags);
/* Try get a page from the freelist if available */
if (!page)
@@ -5127,7 +5128,7 @@ unsigned long __alloc_pages_bulk(gfp_t gfp, int preferred_nid,
__count_zid_vm_events(PGALLOC, zone_idx(zone), 1);
zone_statistics(ac.preferred_zoneref->zone, zone);
- prep_new_page(page, 0, gfp, 0);
+ prep_new_page(page, 0, GFP_ATOMIC, gfp, 0);
if (page_list)
list_add(&page->lru, page_list);
else
diff --git a/mm/page_owner.c b/mm/page_owner.c
index adfabb560eb9..22948724ca64 100644
--- a/mm/page_owner.c
+++ b/mm/page_owner.c
@@ -170,7 +170,7 @@ static inline void __set_page_owner_handle(struct page_ext *page_ext,
}
noinline void __set_page_owner(struct page *page, unsigned int order,
- gfp_t gfp_mask)
+ gfp_t alloc_gfp, gfp_t page_gfp_mask)
{
struct page_ext *page_ext = lookup_page_ext(page);
depot_stack_handle_t handle;
@@ -178,8 +178,8 @@ noinline void __set_page_owner(struct page *page, unsigned int order,
if (unlikely(!page_ext))
return;
- handle = save_stack(gfp_mask);
- __set_page_owner_handle(page_ext, handle, order, gfp_mask);
+ handle = save_stack(alloc_gfp);
+ __set_page_owner_handle(page_ext, handle, order, page_gfp_mask);
}
void __set_page_owner_migrate_reason(struct page *page, int reason)
--
2.32.0
On Fri, 9 Jul 2021 17:05:59 +0800 Yang Huan <[email protected]> wrote:
> The problem is caused by set_page_owner alloc memory to save stack with
> GFP_KERNEL in local_riq disabled.
> So, we just can't assume that alloc flags should be same with new page,
> let's split it. But in most situation, same is ok, in alloc_pages_bulk,
> input GFP_ATOMIC when prep_new_pages
Please more fully describe the bug which is being fixed. A link to the
sysbot report would be helpful. I assume there was a stack backtrace
available? Seeing the will help others to understand the bug.
And if you are able to identify the patch which introduced the bug, a
Fixes: tag would be helpful as well.
Thanks.
>
>> The problem is caused by set_page_owner alloc memory to save stack with
>> GFP_KERNEL in local_riq disabled.
>> So, we just can't assume that alloc flags should be same with new page,
>> let's split it. But in most situation, same is ok, in alloc_pages_bulk,
>> input GFP_ATOMIC when prep_new_pages
>
>Please more fully describe the bug which is being fixed. A link to the
>sysbot report would be helpful. I assume there was a stack backtrace
>available? Seeing the will help others to understand the bug.
Sorry, here is the back trace
BUG: sleeping function called from invalid context at mm/page_alloc.c:5179
in_atomic(): 0, irqs_disabled(): 1, non_block: 0, pid: 1, name: swapper/0
__dump_stack lib/dump_stack.c:79 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:96
___might_sleep.cold+0x1f1/0x237 kernel/sched/core.c:9153
prepare_alloc_pages+0x3da/0x580 mm/page_alloc.c:5179
__alloc_pages+0x12f/0x500 mm/page_alloc.c:5375
alloc_pages+0x18c/0x2a0 mm/mempolicy.c:2272
stack_depot_save+0x39d/0x4e0 lib/stackdepot.c:303
save_stack+0x15e/0x1e0 mm/page_owner.c:120
__set_page_owner+0x50/0x290 mm/page_owner.c:181
prep_new_page mm/page_alloc.c:2445 [inline]
__alloc_pages_bulk+0x8b9/0x1870 mm/page_alloc.c:5313
>And if you are able to identify the patch which introduced the bug, a
>Fixes: tag would be helpful as well.
I will send patch again with this descrption.
Thanks
>
>Thanks.
>
HI Andrew
在 2024/4/25 17:52, 杨欢 写道:
>>> The problem is caused by set_page_owner alloc memory to save stack with
>>> GFP_KERNEL in local_riq disabled.
>>> So, we just can't assume that alloc flags should be same with new page,
>>> let's split it. But in most situation, same is ok, in alloc_pages_bulk,
>>> input GFP_ATOMIC when prep_new_pages
>> Please more fully describe the bug which is being fixed. A link to the
>> sysbot report would be helpful. I assume there was a stack backtrace
>> available? Seeing the will help others to understand the bug.
> Sorry, here is the backtrace:
> __dump_stack lib/dump_stack.c:79 [inline]
> dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:96
> ___might_sleep.cold+0x1f1/0x237 kernel/sched/core.c:9153
> prepare_alloc_pages+0x3da/0x580 mm/page_alloc.c:5179
> __alloc_pages+0x12f/0x500 mm/page_alloc.c:5375
> alloc_pages+0x18c/0x2a0 mm/mempolicy.c:2272
> stack_depot_save+0x39d/0x4e0 lib/stackdepot.c:303
> save_stack+0x15e/0x1e0 mm/page_owner.c:120
> __set_page_owner+0x50/0x290 mm/page_owner.c:181
> prep_new_page mm/page_alloc.c:2445 [inline]
> __alloc_pages_bulk+0x8b9/0x1870 mm/page_alloc.c:5313
Thanks for your reply, but this patch was submitted in 2021, at that
time it was believed that bypassing
alloc bulk would suffice when page_owner is enabled, so this patch was
not considered.
Have you recently encountered any issues related to this?
Thanks.
>> And if you are able to identify the patch which introduced the bug, a
>> Fixes: tag would be helpful as well.
>> Thanks.
>>
>
>
>