| 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: Mon, 25 Apr 2022 21:27:22 +0800
From: Miaohe Lin <linmiaohe@...wei.com>
To: <akpm@...ux-foundation.org>, <mike.kravetz@...cle.com>,
<naoya.horiguchi@....com>
CC: <ying.huang@...el.com>, <hch@....de>, <dhowells@...hat.com>,
<cl@...ux.com>, <david@...hat.com>, <linux-mm@...ck.org>,
<linux-kernel@...r.kernel.org>, <linmiaohe@...wei.com>
Subject: [PATCH v2 3/4] mm/migration: return errno when isolate_huge_page failed
We might fail to isolate huge page due to e.g. the page is under migration
which cleared HPageMigratable. So we should return -EBUSY in this case
rather than always return 1 which could confuse the user. Also we make
the prototype of isolate_huge_page consistent with isolate_lru_page to
improve the readability.
Fixes: e8db67eb0ded ("mm: migrate: move_pages() supports thp migration")
Suggested-by: Huang Ying <ying.huang@...el.com>
Signed-off-by: Miaohe Lin <linmiaohe@...wei.com>
---
include/linux/hugetlb.h | 6 +++---
mm/gup.c | 2 +-
mm/hugetlb.c | 11 +++++------
mm/memory-failure.c | 2 +-
mm/mempolicy.c | 2 +-
mm/migrate.c | 5 +++--
6 files changed, 14 insertions(+), 14 deletions(-)
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index 04f0186b089b..306d6ef3fa22 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -170,7 +170,7 @@ bool hugetlb_reserve_pages(struct inode *inode, long from, long to,
vm_flags_t vm_flags);
long hugetlb_unreserve_pages(struct inode *inode, long start, long end,
long freed);
-bool isolate_huge_page(struct page *page, struct list_head *list);
+int isolate_huge_page(struct page *page, struct list_head *list);
int get_hwpoison_huge_page(struct page *page, bool *hugetlb);
int get_huge_page_for_hwpoison(unsigned long pfn, int flags);
void putback_active_hugepage(struct page *page);
@@ -376,9 +376,9 @@ static inline pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr,
return NULL;
}
-static inline bool isolate_huge_page(struct page *page, struct list_head *list)
+static inline int isolate_huge_page(struct page *page, struct list_head *list)
{
- return false;
+ return -EBUSY;
}
static inline int get_hwpoison_huge_page(struct page *page, bool *hugetlb)
diff --git a/mm/gup.c b/mm/gup.c
index 5c17d4816441..c15d41636e8e 100644
--- a/mm/gup.c
+++ b/mm/gup.c
@@ -1869,7 +1869,7 @@ static long check_and_migrate_movable_pages(unsigned long nr_pages,
* Try to move out any movable page before pinning the range.
*/
if (folio_test_hugetlb(folio)) {
- if (!isolate_huge_page(&folio->page,
+ if (isolate_huge_page(&folio->page,
&movable_page_list))
isolation_error_count++;
continue;
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 74c9964c1b11..098f81e8550d 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -2766,8 +2766,7 @@ static int alloc_and_dissolve_huge_page(struct hstate *h, struct page *old_page,
* Fail with -EBUSY if not possible.
*/
spin_unlock_irq(&hugetlb_lock);
- if (!isolate_huge_page(old_page, list))
- ret = -EBUSY;
+ ret = isolate_huge_page(old_page, list);
spin_lock_irq(&hugetlb_lock);
goto free_new;
} else if (!HPageFreed(old_page)) {
@@ -2843,7 +2842,7 @@ int isolate_or_dissolve_huge_page(struct page *page, struct list_head *list)
if (hstate_is_gigantic(h))
return -ENOMEM;
- if (page_count(head) && isolate_huge_page(head, list))
+ if (page_count(head) && !isolate_huge_page(head, list))
ret = 0;
else if (!page_count(head))
ret = alloc_and_dissolve_huge_page(h, head, list);
@@ -6940,15 +6939,15 @@ follow_huge_pgd(struct mm_struct *mm, unsigned long address, pgd_t *pgd, int fla
return pte_page(*(pte_t *)pgd) + ((address & ~PGDIR_MASK) >> PAGE_SHIFT);
}
-bool isolate_huge_page(struct page *page, struct list_head *list)
+int isolate_huge_page(struct page *page, struct list_head *list)
{
- bool ret = true;
+ int ret = 0;
spin_lock_irq(&hugetlb_lock);
if (!PageHeadHuge(page) ||
!HPageMigratable(page) ||
!get_page_unless_zero(page)) {
- ret = false;
+ ret = -EBUSY;
goto unlock;
}
ClearHPageMigratable(page);
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 1d117190c350..a83d32bbc567 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -2203,7 +2203,7 @@ static bool isolate_page(struct page *page, struct list_head *pagelist)
bool lru = PageLRU(page);
if (PageHuge(page)) {
- isolated = isolate_huge_page(page, pagelist);
+ isolated = !isolate_huge_page(page, pagelist);
} else {
if (lru)
isolated = !isolate_lru_page(page);
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index e4f125e48cc4..a4467c4e9f8d 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -602,7 +602,7 @@ static int queue_pages_hugetlb(pte_t *pte, unsigned long hmask,
/* With MPOL_MF_MOVE, we migrate only unshared hugepage. */
if (flags & (MPOL_MF_MOVE_ALL) ||
(flags & MPOL_MF_MOVE && page_mapcount(page) == 1)) {
- if (!isolate_huge_page(page, qp->pagelist) &&
+ if (isolate_huge_page(page, qp->pagelist) &&
(flags & MPOL_MF_STRICT))
/*
* Failed to isolate page but allow migrating pages
diff --git a/mm/migrate.c b/mm/migrate.c
index 0fc4651b3e39..c937a496239b 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -1628,8 +1628,9 @@ static int add_page_for_migration(struct mm_struct *mm, unsigned long addr,
if (PageHuge(page)) {
if (PageHead(page)) {
- isolate_huge_page(page, pagelist);
- err = 1;
+ err = isolate_huge_page(page, pagelist);
+ if (!err)
+ err = 1;
}
} else {
struct page *head;
--
2.23.0
Powered by blists - more mailing lists