* [PATCH v4 0/2] A few fixup patches for memory failure
@ 2022-03-20 5:13 Miaohe Lin
2022-03-20 5:13 ` [PATCH v4 1/2] mm/memory-failure.c: avoid calling invalidate_inode_page() with unexpected pages Miaohe Lin
2022-03-20 5:13 ` [PATCH v4 2/2] mm/memory-failure.c: make non-LRU movable pages unhandlable Miaohe Lin
0 siblings, 2 replies; 5+ messages in thread
From: Miaohe Lin @ 2022-03-20 5:13 UTC (permalink / raw)
To: akpm, naoya.horiguchi, shy828301, mike.kravetz, david
Cc: linux-mm, linux-kernel, linmiaohe
Hi everyone,
This series contains a patch to avoid calling invalidate_inode_page()
with unexpected pages and another one to make non-LRU movable pages
unhandlable. More details can be found in the respective changelogs.
Thanks!
---
v3->v4:
fix typo and drop "bool movable" per David. Thanks David.
v2->v3:
drop patch "mm/memory-failure.c: fix race with changing page compound again"
collect reviewed-by and acked-by tag
fix stale commit id in the commit log
v1->v2:
drop "mm/memory-failure.c: fix wrong user reference report"
make non-LRU movable pages unhandlable
fix confusing commit log and introduce MF_MSG_DIFFERENT_PAGE_SIZE
Many thanks Naoya, Mike and Yang Shi for review!
---
Miaohe Lin (2):
mm/memory-failure.c: avoid calling invalidate_inode_page() with
unexpected pages
mm/memory-failure.c: make non-LRU movable pages unhandlable
mm/memory-failure.c | 20 ++++++++++++--------
1 file changed, 12 insertions(+), 8 deletions(-)
--
2.23.0
^ permalink raw reply [flat|nested] 5+ messages in thread* [PATCH v4 1/2] mm/memory-failure.c: avoid calling invalidate_inode_page() with unexpected pages 2022-03-20 5:13 [PATCH v4 0/2] A few fixup patches for memory failure Miaohe Lin @ 2022-03-20 5:13 ` Miaohe Lin 2022-03-19 16:20 ` Matthew Wilcox 2022-03-20 5:13 ` [PATCH v4 2/2] mm/memory-failure.c: make non-LRU movable pages unhandlable Miaohe Lin 1 sibling, 1 reply; 5+ messages in thread From: Miaohe Lin @ 2022-03-20 5:13 UTC (permalink / raw) To: akpm, naoya.horiguchi, shy828301, mike.kravetz, david Cc: linux-mm, linux-kernel, linmiaohe invalidate_inode_page() can invalidate the pages in the swap cache because the check of page->mapping != mapping is removed via Matthew's patch titled "mm/truncate: Inline invalidate_complete_page() into its one caller". But invalidate_inode_page() is not expected to deal with the pages in the swap cache. Also non-lru movable page can reach here too. They're not page cache pages. Skip these pages by checking PageSwapCache and PageLRU to fix this unexpected issue. Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> --- mm/memory-failure.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 5444a8ef4867..ecf45961f3b6 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -2178,7 +2178,7 @@ static int __soft_offline_page(struct page *page) return 0; } - if (!PageHuge(page)) + if (!PageHuge(page) && PageLRU(page) && !PageSwapCache(page)) /* * Try to invalidate first. This should work for * non dirty unmapped page cache pages. -- 2.23.0 ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH v4 1/2] mm/memory-failure.c: avoid calling invalidate_inode_page() with unexpected pages 2022-03-20 5:13 ` [PATCH v4 1/2] mm/memory-failure.c: avoid calling invalidate_inode_page() with unexpected pages Miaohe Lin @ 2022-03-19 16:20 ` Matthew Wilcox 2022-03-21 2:18 ` Miaohe Lin 0 siblings, 1 reply; 5+ messages in thread From: Matthew Wilcox @ 2022-03-19 16:20 UTC (permalink / raw) To: Miaohe Lin Cc: akpm, naoya.horiguchi, shy828301, mike.kravetz, david, linux-mm, linux-kernel On Sun, Mar 20, 2022 at 01:13:33PM +0800, Miaohe Lin wrote: > invalidate_inode_page() can invalidate the pages in the swap cache because > the check of page->mapping != mapping is removed via Matthew's patch titled > "mm/truncate: Inline invalidate_complete_page() into its one caller". But > invalidate_inode_page() is not expected to deal with the pages in the swap > cache. Also non-lru movable page can reach here too. They're not page cache > pages. Skip these pages by checking PageSwapCache and PageLRU to fix this > unexpected issue. I disagree with this changelog. invalidate_inode_page() should not be called for pages which are not in the page cache. And then the patch shouldn't test PageLRU (which is actually wrong) or PageSwapCache(). It should simply be: + if (!PageHuge(page) && !PageAnon(page)) > Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> > --- > mm/memory-failure.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/memory-failure.c b/mm/memory-failure.c > index 5444a8ef4867..ecf45961f3b6 100644 > --- a/mm/memory-failure.c > +++ b/mm/memory-failure.c > @@ -2178,7 +2178,7 @@ static int __soft_offline_page(struct page *page) > return 0; > } > > - if (!PageHuge(page)) > + if (!PageHuge(page) && PageLRU(page) && !PageSwapCache(page)) > /* > * Try to invalidate first. This should work for > * non dirty unmapped page cache pages. > -- > 2.23.0 > > ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH v4 1/2] mm/memory-failure.c: avoid calling invalidate_inode_page() with unexpected pages 2022-03-19 16:20 ` Matthew Wilcox @ 2022-03-21 2:18 ` Miaohe Lin 0 siblings, 0 replies; 5+ messages in thread From: Miaohe Lin @ 2022-03-21 2:18 UTC (permalink / raw) To: Matthew Wilcox Cc: akpm, naoya.horiguchi, shy828301, mike.kravetz, david, linux-mm, linux-kernel On 2022/3/20 0:20, Matthew Wilcox wrote: > On Sun, Mar 20, 2022 at 01:13:33PM +0800, Miaohe Lin wrote: >> invalidate_inode_page() can invalidate the pages in the swap cache because >> the check of page->mapping != mapping is removed via Matthew's patch titled >> "mm/truncate: Inline invalidate_complete_page() into its one caller". But >> invalidate_inode_page() is not expected to deal with the pages in the swap >> cache. Also non-lru movable page can reach here too. They're not page cache >> pages. Skip these pages by checking PageSwapCache and PageLRU to fix this >> unexpected issue. > > I disagree with this changelog. > > invalidate_inode_page() should not be called for pages which are not > in the page cache. > > And then the patch shouldn't test PageLRU (which is actually wrong) or > PageSwapCache(). It should simply be: > > + if (!PageHuge(page) && !PageAnon(page)) If we reach here, the page can be one of the PageHuge, __PageMovable and PageLRU. If above code is used, __PageMovable can pass the check and enter the invalidate_inode_page unexpectedly. So I think PageLRU check is necessary here. But it seems PageSwapCache is only reliable when PageAnon, so might we should do: + if (!PageHuge(page) && PageLRU(page) && !PageAnon(page)) Am I miss something? Many thanks for comment. > >> Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> >> --- >> mm/memory-failure.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/mm/memory-failure.c b/mm/memory-failure.c >> index 5444a8ef4867..ecf45961f3b6 100644 >> --- a/mm/memory-failure.c >> +++ b/mm/memory-failure.c >> @@ -2178,7 +2178,7 @@ static int __soft_offline_page(struct page *page) >> return 0; >> } >> >> - if (!PageHuge(page)) >> + if (!PageHuge(page) && PageLRU(page) && !PageSwapCache(page)) >> /* >> * Try to invalidate first. This should work for >> * non dirty unmapped page cache pages. >> -- >> 2.23.0 >> >> > > . > ^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH v4 2/2] mm/memory-failure.c: make non-LRU movable pages unhandlable 2022-03-20 5:13 [PATCH v4 0/2] A few fixup patches for memory failure Miaohe Lin 2022-03-20 5:13 ` [PATCH v4 1/2] mm/memory-failure.c: avoid calling invalidate_inode_page() with unexpected pages Miaohe Lin @ 2022-03-20 5:13 ` Miaohe Lin 1 sibling, 0 replies; 5+ messages in thread From: Miaohe Lin @ 2022-03-20 5:13 UTC (permalink / raw) To: akpm, naoya.horiguchi, shy828301, mike.kravetz, david Cc: linux-mm, linux-kernel, linmiaohe We can not really handle non-LRU movable pages in memory failure. Typically they are balloon, zsmalloc, etc. Assuming we run into a base (4K) non-LRU movable page, we could reach as far as identify_page_state(), it should not fall into any category except me_unknown. For the non-LRU compound movable pages, they could be taken for transhuge pages but it's unexpected to split non-LRU movable pages using split_huge_page_to_list in memory_failure. So we could just simply make non-LRU movable pages unhandlable to avoid these possible nasty cases. Suggested-by: Yang Shi <shy828301@gmail.com> Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Reviewed-by: Yang Shi <shy828301@gmail.com> Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com> --- mm/memory-failure.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index ecf45961f3b6..837ceae90d64 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1176,12 +1176,16 @@ void ClearPageHWPoisonTakenOff(struct page *page) * does not return true for hugetlb or device memory pages, so it's assumed * to be called only in the context where we never have such pages. */ -static inline bool HWPoisonHandlable(struct page *page) +static inline bool HWPoisonHandlable(struct page *page, unsigned long flags) { - return PageLRU(page) || __PageMovable(page) || is_free_buddy_page(page); + /* Soft offline could migrate non-LRU movable pages. */ + if ((flags & MF_SOFT_OFFLINE) && __PageMovable(page)) + return true; + + return PageLRU(page) || is_free_buddy_page(page); } -static int __get_hwpoison_page(struct page *page) +static int __get_hwpoison_page(struct page *page, unsigned long flags) { struct page *head = compound_head(page); int ret = 0; @@ -1196,7 +1200,7 @@ static int __get_hwpoison_page(struct page *page) * for any unsupported type of page in order to reduce the risk of * unexpected races caused by taking a page refcount. */ - if (!HWPoisonHandlable(head)) + if (!HWPoisonHandlable(head, flags)) return -EBUSY; if (get_page_unless_zero(head)) { @@ -1221,7 +1225,7 @@ static int get_any_page(struct page *p, unsigned long flags) try_again: if (!count_increased) { - ret = __get_hwpoison_page(p); + ret = __get_hwpoison_page(p, flags); if (!ret) { if (page_count(p)) { /* We raced with an allocation, retry. */ @@ -1249,7 +1253,7 @@ static int get_any_page(struct page *p, unsigned long flags) } } - if (PageHuge(p) || HWPoisonHandlable(p)) { + if (PageHuge(p) || HWPoisonHandlable(p, flags)) { ret = 1; } else { /* @@ -2296,7 +2300,7 @@ int soft_offline_page(unsigned long pfn, int flags) retry: get_online_mems(); - ret = get_hwpoison_page(page, flags); + ret = get_hwpoison_page(page, flags | MF_SOFT_OFFLINE); put_online_mems(); if (ret > 0) { -- 2.23.0 ^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2022-03-21 2:18 UTC | newest] Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2022-03-20 5:13 [PATCH v4 0/2] A few fixup patches for memory failure Miaohe Lin 2022-03-20 5:13 ` [PATCH v4 1/2] mm/memory-failure.c: avoid calling invalidate_inode_page() with unexpected pages Miaohe Lin 2022-03-19 16:20 ` Matthew Wilcox 2022-03-21 2:18 ` Miaohe Lin 2022-03-20 5:13 ` [PATCH v4 2/2] mm/memory-failure.c: make non-LRU movable pages unhandlable Miaohe Lin
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