* + mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison.patch added to mm-hotfixes-unstable branch
@ 2025-12-16 22:20 Andrew Morton
0 siblings, 0 replies; 6+ messages in thread
From: Andrew Morton @ 2025-12-16 22:20 UTC (permalink / raw)
To: mm-commits, william.roche, surenb, stable, rppt, rientjes,
osalvador, muchun.song, mhocko, lorenzo.stoakes, linmiaohe,
liam.howlett, jiaqiyan, jane.chu, akpm
The patch titled
Subject: mm/memory-failure: fix missing ->mf_stats count in hugetlb poison
has been added to the -mm mm-hotfixes-unstable branch. Its filename is
mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison.patch
This patch will later appear in the mm-hotfixes-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via various
branches at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there most days
------------------------------------------------------
From: Jane Chu <jane.chu@oracle.com>
Subject: mm/memory-failure: fix missing ->mf_stats count in hugetlb poison
Date: Tue, 16 Dec 2025 14:56:21 -0700
When a newly poisoned subpage ends up in an already poisoned hugetlb
folio, 'num_poisoned_pages' is incremented, but the per node ->mf_stats is
not. Fix the inconsistency by designating action_result() to update them
both.
Link: https://lkml.kernel.org/r/20251216215621.920093-1-jane.chu@oracle.com
Fixes: 18f41fa616ee4 ("mm: memory-failure: bump memory failure stats to pglist_data")
Signed-off-by: Jane Chu <jane.chu@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Jiaqi Yan <jiaqiyan@google.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: William Roche <william.roche@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
include/linux/hugetlb.h | 4 ++--
include/linux/mm.h | 4 ++--
mm/hugetlb.c | 4 ++--
mm/memory-failure.c | 22 +++++++++++++---------
4 files changed, 19 insertions(+), 15 deletions(-)
--- a/include/linux/hugetlb.h~mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison
+++ a/include/linux/hugetlb.h
@@ -156,7 +156,7 @@ long hugetlb_unreserve_pages(struct inod
bool folio_isolate_hugetlb(struct folio *folio, struct list_head *list);
int get_hwpoison_hugetlb_folio(struct folio *folio, bool *hugetlb, bool unpoison);
int get_huge_page_for_hwpoison(unsigned long pfn, int flags,
- bool *migratable_cleared);
+ bool *migratable_cleared, bool *samepg);
void folio_putback_hugetlb(struct folio *folio);
void move_hugetlb_state(struct folio *old_folio, struct folio *new_folio, int reason);
void hugetlb_fix_reserve_counts(struct inode *inode);
@@ -418,7 +418,7 @@ static inline int get_hwpoison_hugetlb_f
}
static inline int get_huge_page_for_hwpoison(unsigned long pfn, int flags,
- bool *migratable_cleared)
+ bool *migratable_cleared, bool *samepg)
{
return 0;
}
--- a/include/linux/mm.h~mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison
+++ a/include/linux/mm.h
@@ -4351,7 +4351,7 @@ extern int soft_offline_page(unsigned lo
extern const struct attribute_group memory_failure_attr_group;
extern void memory_failure_queue(unsigned long pfn, int flags);
extern int __get_huge_page_for_hwpoison(unsigned long pfn, int flags,
- bool *migratable_cleared);
+ bool *migratable_cleared, bool *samepg);
void num_poisoned_pages_inc(unsigned long pfn);
void num_poisoned_pages_sub(unsigned long pfn, long i);
#else
@@ -4360,7 +4360,7 @@ static inline void memory_failure_queue(
}
static inline int __get_huge_page_for_hwpoison(unsigned long pfn, int flags,
- bool *migratable_cleared)
+ bool *migratable_cleared, bool *samepg)
{
return 0;
}
--- a/mm/hugetlb.c~mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison
+++ a/mm/hugetlb.c
@@ -7132,12 +7132,12 @@ int get_hwpoison_hugetlb_folio(struct fo
}
int get_huge_page_for_hwpoison(unsigned long pfn, int flags,
- bool *migratable_cleared)
+ bool *migratable_cleared, bool *samepg)
{
int ret;
spin_lock_irq(&hugetlb_lock);
- ret = __get_huge_page_for_hwpoison(pfn, flags, migratable_cleared);
+ ret = __get_huge_page_for_hwpoison(pfn, flags, migratable_cleared, samepg);
spin_unlock_irq(&hugetlb_lock);
return ret;
}
--- a/mm/memory-failure.c~mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison
+++ a/mm/memory-failure.c
@@ -1883,7 +1883,8 @@ static unsigned long __folio_free_raw_hw
return count;
}
-static int folio_set_hugetlb_hwpoison(struct folio *folio, struct page *page)
+static int folio_set_hugetlb_hwpoison(struct folio *folio, struct page *page,
+ bool *samepg)
{
struct llist_head *head;
struct raw_hwp_page *raw_hwp;
@@ -1899,17 +1900,16 @@ static int folio_set_hugetlb_hwpoison(st
return -EHWPOISON;
head = raw_hwp_list_head(folio);
llist_for_each_entry(p, head->first, node) {
- if (p->page == page)
+ if (p->page == page) {
+ *samepg = true;
return -EHWPOISON;
+ }
}
raw_hwp = kmalloc(sizeof(struct raw_hwp_page), GFP_ATOMIC);
if (raw_hwp) {
raw_hwp->page = page;
llist_add(&raw_hwp->node, head);
- /* the first error event will be counted in action_result(). */
- if (ret)
- num_poisoned_pages_inc(page_to_pfn(page));
} else {
/*
* Failed to save raw error info. We no longer trace all
@@ -1966,7 +1966,7 @@ void folio_clear_hugetlb_hwpoison(struct
* -EHWPOISON - the hugepage is already hwpoisoned
*/
int __get_huge_page_for_hwpoison(unsigned long pfn, int flags,
- bool *migratable_cleared)
+ bool *migratable_cleared, bool *samepg)
{
struct page *page = pfn_to_page(pfn);
struct folio *folio = page_folio(page);
@@ -1991,7 +1991,7 @@ int __get_huge_page_for_hwpoison(unsigne
goto out;
}
- if (folio_set_hugetlb_hwpoison(folio, page)) {
+ if (folio_set_hugetlb_hwpoison(folio, page, samepg)) {
ret = -EHWPOISON;
goto out;
}
@@ -2024,11 +2024,12 @@ static int try_memory_failure_hugetlb(un
struct page *p = pfn_to_page(pfn);
struct folio *folio;
unsigned long page_flags;
+ bool samepg = false;
bool migratable_cleared = false;
*hugetlb = 1;
retry:
- res = get_huge_page_for_hwpoison(pfn, flags, &migratable_cleared);
+ res = get_huge_page_for_hwpoison(pfn, flags, &migratable_cleared, &samepg);
if (res == 2) { /* fallback to normal page handling */
*hugetlb = 0;
return 0;
@@ -2037,7 +2038,10 @@ retry:
folio = page_folio(p);
res = kill_accessing_process(current, folio_pfn(folio), flags);
}
- action_result(pfn, MF_MSG_ALREADY_POISONED, MF_FAILED);
+ if (samepg)
+ action_result(pfn, MF_MSG_ALREADY_POISONED, MF_FAILED);
+ else
+ action_result(pfn, MF_MSG_HUGE, MF_FAILED);
return res;
} else if (res == -EBUSY) {
if (!(flags & MF_NO_RETRY)) {
_
Patches currently in -mm which might be from jane.chu@oracle.com are
mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison.patch
^ permalink raw reply [flat|nested] 6+ messages in thread
* + mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison.patch added to mm-hotfixes-unstable branch
@ 2025-12-20 22:06 Andrew Morton
0 siblings, 0 replies; 6+ messages in thread
From: Andrew Morton @ 2025-12-20 22:06 UTC (permalink / raw)
To: mm-commits, william.roche, surenb, stable, rppt, rientjes,
osalvador, muchun.song, mhocko, lorenzo.stoakes, linmiaohe,
liam.howlett, jiaqiyan, david, jane.chu, akpm
The patch titled
Subject: mm/memory-failure: fix missing ->mf_stats count in hugetlb poison
has been added to the -mm mm-hotfixes-unstable branch. Its filename is
mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison.patch
This patch will later appear in the mm-hotfixes-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via various
branches at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there most days
------------------------------------------------------
From: Jane Chu <jane.chu@oracle.com>
Subject: mm/memory-failure: fix missing ->mf_stats count in hugetlb poison
Date: Fri, 19 Dec 2025 12:15:58 -0700
When a newly poisoned subpage ends up in an already poisoned hugetlb
folio, 'num_poisoned_pages' is incremented, but the per node ->mf_stats is
not. Fix the inconsistency by designating action_result() to update them
both.
While at it, define __get_huge_page_for_hwpoison() return values in terms
of symbol names for better readibility. Also rename
folio_set_hugetlb_hwpoison() to hugetlb_update_hwpoison() since the
function does more than the conventional bit setting and the fact three
possible return values are expected.
Link: https://lkml.kernel.org/r/20251219191559.2962716-1-jane.chu@oracle.com
Fixes: 18f41fa616ee4 ("mm: memory-failure: bump memory failure stats to pglist_data")
Signed-off-by: Jane Chu <jane.chu@oracle.com>
Cc: "David Hildenbrand (Red Hat)" <david@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Jiaqi Yan <jiaqiyan@google.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: William Roche <william.roche@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
mm/memory-failure.c | 56 ++++++++++++++++++++++++------------------
1 file changed, 33 insertions(+), 23 deletions(-)
--- a/mm/memory-failure.c~mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison
+++ a/mm/memory-failure.c
@@ -1883,12 +1883,18 @@ static unsigned long __folio_free_raw_hw
return count;
}
-static int folio_set_hugetlb_hwpoison(struct folio *folio, struct page *page)
+#define MF_HUGETLB_ALREADY_POISONED 3 /* already poisoned */
+#define MF_HUGETLB_ACC_EXISTING_POISON 4 /* accessed existing poisoned page */
+/*
+ * Set hugetlb folio as hwpoisoned, update folio private raw hwpoison list
+ * to keep track of the poisoned pages.
+ */
+static int hugetlb_update_hwpoison(struct folio *folio, struct page *page)
{
struct llist_head *head;
struct raw_hwp_page *raw_hwp;
struct raw_hwp_page *p;
- int ret = folio_test_set_hwpoison(folio) ? -EHWPOISON : 0;
+ int ret = folio_test_set_hwpoison(folio) ? MF_HUGETLB_ALREADY_POISONED : 0;
/*
* Once the hwpoison hugepage has lost reliable raw error info,
@@ -1896,20 +1902,18 @@ static int folio_set_hugetlb_hwpoison(st
* so skip to add additional raw error info.
*/
if (folio_test_hugetlb_raw_hwp_unreliable(folio))
- return -EHWPOISON;
+ return MF_HUGETLB_ALREADY_POISONED;
+
head = raw_hwp_list_head(folio);
llist_for_each_entry(p, head->first, node) {
if (p->page == page)
- return -EHWPOISON;
+ return MF_HUGETLB_ACC_EXISTING_POISON;
}
raw_hwp = kmalloc(sizeof(struct raw_hwp_page), GFP_ATOMIC);
if (raw_hwp) {
raw_hwp->page = page;
llist_add(&raw_hwp->node, head);
- /* the first error event will be counted in action_result(). */
- if (ret)
- num_poisoned_pages_inc(page_to_pfn(page));
} else {
/*
* Failed to save raw error info. We no longer trace all
@@ -1955,32 +1959,30 @@ void folio_clear_hugetlb_hwpoison(struct
folio_free_raw_hwp(folio, true);
}
+#define MF_HUGETLB_FREED 0 /* freed hugepage */
+#define MF_HUGETLB_IN_USED 1 /* in-use hugepage */
+#define MF_NOT_HUGETLB 2 /* not a hugepage */
+
/*
* Called from hugetlb code with hugetlb_lock held.
- *
- * Return values:
- * 0 - free hugepage
- * 1 - in-use hugepage
- * 2 - not a hugepage
- * -EBUSY - the hugepage is busy (try to retry)
- * -EHWPOISON - the hugepage is already hwpoisoned
*/
int __get_huge_page_for_hwpoison(unsigned long pfn, int flags,
bool *migratable_cleared)
{
struct page *page = pfn_to_page(pfn);
struct folio *folio = page_folio(page);
- int ret = 2; /* fallback to normal page handling */
+ int ret = MF_NOT_HUGETLB;
bool count_increased = false;
+ int rc;
if (!folio_test_hugetlb(folio))
goto out;
if (flags & MF_COUNT_INCREASED) {
- ret = 1;
+ ret = MF_HUGETLB_IN_USED;
count_increased = true;
} else if (folio_test_hugetlb_freed(folio)) {
- ret = 0;
+ ret = MF_HUGETLB_FREED;
} else if (folio_test_hugetlb_migratable(folio)) {
ret = folio_try_get(folio);
if (ret)
@@ -1991,8 +1993,9 @@ int __get_huge_page_for_hwpoison(unsigne
goto out;
}
- if (folio_set_hugetlb_hwpoison(folio, page)) {
- ret = -EHWPOISON;
+ rc = hugetlb_update_hwpoison(folio, page);
+ if (rc >= MF_HUGETLB_ALREADY_POISONED) {
+ ret = rc;
goto out;
}
@@ -2029,22 +2032,29 @@ static int try_memory_failure_hugetlb(un
*hugetlb = 1;
retry:
res = get_huge_page_for_hwpoison(pfn, flags, &migratable_cleared);
- if (res == 2) { /* fallback to normal page handling */
+ switch (res) {
+ case MF_NOT_HUGETLB: /* fallback to normal page handling */
*hugetlb = 0;
return 0;
- } else if (res == -EHWPOISON) {
+ case MF_HUGETLB_ALREADY_POISONED:
+ case MF_HUGETLB_ACC_EXISTING_POISON:
if (flags & MF_ACTION_REQUIRED) {
folio = page_folio(p);
res = kill_accessing_process(current, folio_pfn(folio), flags);
}
- action_result(pfn, MF_MSG_ALREADY_POISONED, MF_FAILED);
+ if (res == MF_HUGETLB_ALREADY_POISONED)
+ action_result(pfn, MF_MSG_ALREADY_POISONED, MF_FAILED);
+ else
+ action_result(pfn, MF_MSG_HUGE, MF_FAILED);
return res;
- } else if (res == -EBUSY) {
+ case -EBUSY:
if (!(flags & MF_NO_RETRY)) {
flags |= MF_NO_RETRY;
goto retry;
}
return action_result(pfn, MF_MSG_GET_HWPOISON, MF_IGNORED);
+ default:
+ break;
}
folio = page_folio(p);
_
Patches currently in -mm which might be from jane.chu@oracle.com are
mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison.patch
^ permalink raw reply [flat|nested] 6+ messages in thread
* + mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison.patch added to mm-hotfixes-unstable branch
@ 2025-12-23 2:20 Andrew Morton
0 siblings, 0 replies; 6+ messages in thread
From: Andrew Morton @ 2025-12-23 2:20 UTC (permalink / raw)
To: mm-commits, willy, william.roche, surenb, stable, rppt, rientjes,
osalvador, muchun.song, mhocko, lorenzo.stoakes, linmiaohe,
Liam.Howlett, jiaqiyan, david, jane.chu, akpm
The patch titled
Subject: mm/memory-failure: fix missing ->mf_stats count in hugetlb poison
has been added to the -mm mm-hotfixes-unstable branch. Its filename is
mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison.patch
This patch will later appear in the mm-hotfixes-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via various
branches at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there most days
------------------------------------------------------
From: Jane Chu <jane.chu@oracle.com>
Subject: mm/memory-failure: fix missing ->mf_stats count in hugetlb poison
Date: Mon, 22 Dec 2025 18:21:11 -0700
When a newly poisoned subpage ends up in an already poisoned hugetlb
folio, 'num_poisoned_pages' is incremented, but the per node ->mf_stats is
not. Fix the inconsistency by designating action_result() to update them
both.
While at it, define __get_huge_page_for_hwpoison() return values in terms
of symbol names for better readibility. Also rename
folio_set_hugetlb_hwpoison() to hugetlb_update_hwpoison() since the
function does more than the conventional bit setting and the fact three
possible return values are expected.
Link: https://lkml.kernel.org/r/20251223012113.370674-1-jane.chu@oracle.com
Fixes: 18f41fa616ee ("mm: memory-failure: bump memory failure stats to pglist_data")
Signed-off-by: Jane Chu <jane.chu@oracle.com>
Cc: "David Hildenbrand (Red Hat)" <david@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Jiaqi Yan <jiaqiyan@google.com>
Cc: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: William Roche <william.roche@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
mm/memory-failure.c | 56 ++++++++++++++++++++++++------------------
1 file changed, 33 insertions(+), 23 deletions(-)
--- a/mm/memory-failure.c~mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison
+++ a/mm/memory-failure.c
@@ -1883,12 +1883,18 @@ static unsigned long __folio_free_raw_hw
return count;
}
-static int folio_set_hugetlb_hwpoison(struct folio *folio, struct page *page)
+#define MF_HUGETLB_ALREADY_POISONED 3 /* already poisoned */
+#define MF_HUGETLB_ACC_EXISTING_POISON 4 /* accessed existing poisoned page */
+/*
+ * Set hugetlb folio as hwpoisoned, update folio private raw hwpoison list
+ * to keep track of the poisoned pages.
+ */
+static int hugetlb_update_hwpoison(struct folio *folio, struct page *page)
{
struct llist_head *head;
struct raw_hwp_page *raw_hwp;
struct raw_hwp_page *p;
- int ret = folio_test_set_hwpoison(folio) ? -EHWPOISON : 0;
+ int ret = folio_test_set_hwpoison(folio) ? MF_HUGETLB_ALREADY_POISONED : 0;
/*
* Once the hwpoison hugepage has lost reliable raw error info,
@@ -1896,20 +1902,18 @@ static int folio_set_hugetlb_hwpoison(st
* so skip to add additional raw error info.
*/
if (folio_test_hugetlb_raw_hwp_unreliable(folio))
- return -EHWPOISON;
+ return MF_HUGETLB_ALREADY_POISONED;
+
head = raw_hwp_list_head(folio);
llist_for_each_entry(p, head->first, node) {
if (p->page == page)
- return -EHWPOISON;
+ return MF_HUGETLB_ACC_EXISTING_POISON;
}
raw_hwp = kmalloc(sizeof(struct raw_hwp_page), GFP_ATOMIC);
if (raw_hwp) {
raw_hwp->page = page;
llist_add(&raw_hwp->node, head);
- /* the first error event will be counted in action_result(). */
- if (ret)
- num_poisoned_pages_inc(page_to_pfn(page));
} else {
/*
* Failed to save raw error info. We no longer trace all
@@ -1955,32 +1959,30 @@ void folio_clear_hugetlb_hwpoison(struct
folio_free_raw_hwp(folio, true);
}
+#define MF_HUGETLB_FREED 0 /* freed hugepage */
+#define MF_HUGETLB_IN_USED 1 /* in-use hugepage */
+#define MF_NOT_HUGETLB 2 /* not a hugepage */
+
/*
* Called from hugetlb code with hugetlb_lock held.
- *
- * Return values:
- * 0 - free hugepage
- * 1 - in-use hugepage
- * 2 - not a hugepage
- * -EBUSY - the hugepage is busy (try to retry)
- * -EHWPOISON - the hugepage is already hwpoisoned
*/
int __get_huge_page_for_hwpoison(unsigned long pfn, int flags,
bool *migratable_cleared)
{
struct page *page = pfn_to_page(pfn);
struct folio *folio = page_folio(page);
- int ret = 2; /* fallback to normal page handling */
+ int ret = MF_NOT_HUGETLB;
bool count_increased = false;
+ int rc;
if (!folio_test_hugetlb(folio))
goto out;
if (flags & MF_COUNT_INCREASED) {
- ret = 1;
+ ret = MF_HUGETLB_IN_USED;
count_increased = true;
} else if (folio_test_hugetlb_freed(folio)) {
- ret = 0;
+ ret = MF_HUGETLB_FREED;
} else if (folio_test_hugetlb_migratable(folio)) {
ret = folio_try_get(folio);
if (ret)
@@ -1991,8 +1993,9 @@ int __get_huge_page_for_hwpoison(unsigne
goto out;
}
- if (folio_set_hugetlb_hwpoison(folio, page)) {
- ret = -EHWPOISON;
+ rc = hugetlb_update_hwpoison(folio, page);
+ if (rc >= MF_HUGETLB_ALREADY_POISONED) {
+ ret = rc;
goto out;
}
@@ -2029,22 +2032,29 @@ static int try_memory_failure_hugetlb(un
*hugetlb = 1;
retry:
res = get_huge_page_for_hwpoison(pfn, flags, &migratable_cleared);
- if (res == 2) { /* fallback to normal page handling */
+ switch (res) {
+ case MF_NOT_HUGETLB: /* fallback to normal page handling */
*hugetlb = 0;
return 0;
- } else if (res == -EHWPOISON) {
+ case MF_HUGETLB_ALREADY_POISONED:
+ case MF_HUGETLB_ACC_EXISTING_POISON:
if (flags & MF_ACTION_REQUIRED) {
folio = page_folio(p);
res = kill_accessing_process(current, folio_pfn(folio), flags);
}
- action_result(pfn, MF_MSG_ALREADY_POISONED, MF_FAILED);
+ if (res == MF_HUGETLB_ALREADY_POISONED)
+ action_result(pfn, MF_MSG_ALREADY_POISONED, MF_FAILED);
+ else
+ action_result(pfn, MF_MSG_HUGE, MF_FAILED);
return res;
- } else if (res == -EBUSY) {
+ case -EBUSY:
if (!(flags & MF_NO_RETRY)) {
flags |= MF_NO_RETRY;
goto retry;
}
return action_result(pfn, MF_MSG_GET_HWPOISON, MF_IGNORED);
+ default:
+ break;
}
folio = page_folio(p);
_
Patches currently in -mm which might be from jane.chu@oracle.com are
mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison.patch
mm-memory-failure-teach-kill_accessing_process-to-accept-hugetlb-tail-page-pfn.patch
^ permalink raw reply [flat|nested] 6+ messages in thread
* + mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison.patch added to mm-hotfixes-unstable branch
@ 2026-01-13 23:23 Andrew Morton
0 siblings, 0 replies; 6+ messages in thread
From: Andrew Morton @ 2026-01-13 23:23 UTC (permalink / raw)
To: mm-commits, willy, william.roche, surenb, stable, rppt, rientjes,
osalvador, nao.horiguchi, muchun.song, mhocko, lorenzo.stoakes,
linmiaohe, liam.howlett, jiaqiyan, david, jane.chu, akpm
The patch titled
Subject: mm/memory-failure: fix missing ->mf_stats count in hugetlb poison
has been added to the -mm mm-hotfixes-unstable branch. Its filename is
mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison.patch
This patch will later appear in the mm-hotfixes-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via various
branches at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there most days
------------------------------------------------------
From: Jane Chu <jane.chu@oracle.com>
Subject: mm/memory-failure: fix missing ->mf_stats count in hugetlb poison
Date: Tue, 13 Jan 2026 01:07:50 -0700
When a newly poisoned subpage ends up in an already poisoned hugetlb
folio, 'num_poisoned_pages' is incremented, but the per node ->mf_stats is
not. Fix the inconsistency by designating action_result() to update them
both.
While at it, define __get_huge_page_for_hwpoison() return values in terms
of symbol names for better readibility. Also rename
folio_set_hugetlb_hwpoison() to hugetlb_update_hwpoison() since the
function does more than the conventional bit setting and the fact three
possible return values are expected.
Link: https://lkml.kernel.org/r/20260113080751.2173497-1-jane.chu@oracle.com
Fixes: 18f41fa616ee4 ("mm: memory-failure: bump memory failure stats to pglist_data")
Signed-off-by: Jane Chu <jane.chu@oracle.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Jiaqi Yan <jiaqiyan@google.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: William Roche <william.roche@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
mm/memory-failure.c | 75 +++++++++++++++++++++++++-----------------
1 file changed, 45 insertions(+), 30 deletions(-)
--- a/mm/memory-failure.c~mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison
+++ a/mm/memory-failure.c
@@ -1883,12 +1883,24 @@ static unsigned long __folio_free_raw_hw
return count;
}
-static int folio_set_hugetlb_hwpoison(struct folio *folio, struct page *page)
+#define MF_HUGETLB_FOLIO_PRE_POISONED 3 /* folio already poisoned */
+#define MF_HUGETLB_PAGE_PRE_POISON 4 /* exact page already poisoned */
+/*
+ * Set hugetlb folio as hwpoisoned, update folio private raw hwpoison list
+ * to keep track of the poisoned pages.
+ * Return:
+ * 0: folio was not already poisoned;
+ * MF_HUGETLB_FOLIO_PRE_POISONED: folio was already poisoned: either
+ * multiple pages being poisoned, or per page information unclear,
+ * MF_HUGETLB_PAGE_PRE_POISON: folio was already poisoned, an exact
+ * poisoned page is being consumed again.
+ */
+static int hugetlb_update_hwpoison(struct folio *folio, struct page *page)
{
struct llist_head *head;
struct raw_hwp_page *raw_hwp;
struct raw_hwp_page *p;
- int ret = folio_test_set_hwpoison(folio) ? -EHWPOISON : 0;
+ int ret = folio_test_set_hwpoison(folio) ? MF_HUGETLB_FOLIO_PRE_POISONED : 0;
/*
* Once the hwpoison hugepage has lost reliable raw error info,
@@ -1896,20 +1908,17 @@ static int folio_set_hugetlb_hwpoison(st
* so skip to add additional raw error info.
*/
if (folio_test_hugetlb_raw_hwp_unreliable(folio))
- return -EHWPOISON;
+ return MF_HUGETLB_FOLIO_PRE_POISONED;
head = raw_hwp_list_head(folio);
llist_for_each_entry(p, head->first, node) {
if (p->page == page)
- return -EHWPOISON;
+ return MF_HUGETLB_PAGE_PRE_POISON;
}
raw_hwp = kmalloc(sizeof(struct raw_hwp_page), GFP_ATOMIC);
if (raw_hwp) {
raw_hwp->page = page;
llist_add(&raw_hwp->node, head);
- /* the first error event will be counted in action_result(). */
- if (ret)
- num_poisoned_pages_inc(page_to_pfn(page));
} else {
/*
* Failed to save raw error info. We no longer trace all
@@ -1955,44 +1964,43 @@ void folio_clear_hugetlb_hwpoison(struct
folio_free_raw_hwp(folio, true);
}
+#define MF_HUGETLB_FREED 0 /* freed hugepage */
+#define MF_HUGETLB_IN_USED 1 /* in-use hugepage */
/*
* Called from hugetlb code with hugetlb_lock held.
- *
- * Return values:
- * 0 - free hugepage
- * 1 - in-use hugepage
- * 2 - not a hugepage
- * -EBUSY - the hugepage is busy (try to retry)
- * -EHWPOISON - the hugepage is already hwpoisoned
*/
int __get_huge_page_for_hwpoison(unsigned long pfn, int flags,
bool *migratable_cleared)
{
struct page *page = pfn_to_page(pfn);
struct folio *folio = page_folio(page);
- int ret = 2; /* fallback to normal page handling */
+ int ret = -EINVAL;
bool count_increased = false;
+ int rc;
if (!folio_test_hugetlb(folio))
goto out;
if (flags & MF_COUNT_INCREASED) {
- ret = 1;
+ ret = MF_HUGETLB_IN_USED;
count_increased = true;
} else if (folio_test_hugetlb_freed(folio)) {
- ret = 0;
+ ret = MF_HUGETLB_FREED;
} else if (folio_test_hugetlb_migratable(folio)) {
- ret = folio_try_get(folio);
- if (ret)
+ if (folio_try_get(folio)) {
+ ret = MF_HUGETLB_IN_USED;
count_increased = true;
+ } else
+ ret = MF_HUGETLB_FREED;
} else {
ret = -EBUSY;
if (!(flags & MF_NO_RETRY))
goto out;
}
- if (folio_set_hugetlb_hwpoison(folio, page)) {
- ret = -EHWPOISON;
+ rc = hugetlb_update_hwpoison(folio, page);
+ if (rc >= MF_HUGETLB_FOLIO_PRE_POISONED) {
+ ret = rc;
goto out;
}
@@ -2029,22 +2037,29 @@ static int try_memory_failure_hugetlb(un
*hugetlb = 1;
retry:
res = get_huge_page_for_hwpoison(pfn, flags, &migratable_cleared);
- if (res == 2) { /* fallback to normal page handling */
+ switch (res) {
+ case -EINVAL: /* fallback to normal page handling */
*hugetlb = 0;
return 0;
- } else if (res == -EHWPOISON) {
- if (flags & MF_ACTION_REQUIRED) {
- folio = page_folio(p);
- res = kill_accessing_process(current, folio_pfn(folio), flags);
- }
- action_result(pfn, MF_MSG_ALREADY_POISONED, MF_FAILED);
- return res;
- } else if (res == -EBUSY) {
+ case -EBUSY:
if (!(flags & MF_NO_RETRY)) {
flags |= MF_NO_RETRY;
goto retry;
}
return action_result(pfn, MF_MSG_GET_HWPOISON, MF_IGNORED);
+ case MF_HUGETLB_FOLIO_PRE_POISONED:
+ case MF_HUGETLB_PAGE_PRE_POISON:
+ if (flags & MF_ACTION_REQUIRED) {
+ folio = page_folio(p);
+ res = kill_accessing_process(current, folio_pfn(folio), flags);
+ }
+ if (res == MF_HUGETLB_FOLIO_PRE_POISONED)
+ action_result(pfn, MF_MSG_ALREADY_POISONED, MF_FAILED);
+ else
+ action_result(pfn, MF_MSG_HUGE, MF_FAILED);
+ return res;
+ default:
+ break;
}
folio = page_folio(p);
_
Patches currently in -mm which might be from jane.chu@oracle.com are
mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison.patch
mm-memory-failure-teach-kill_accessing_process-to-accept-hugetlb-tail-page-pfn.patch
^ permalink raw reply [flat|nested] 6+ messages in thread
* + mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison.patch added to mm-hotfixes-unstable branch
@ 2026-01-17 2:59 Andrew Morton
0 siblings, 0 replies; 6+ messages in thread
From: Andrew Morton @ 2026-01-17 2:59 UTC (permalink / raw)
To: mm-commits, willy, surenb, stable, rppt, rientjes, osalvador,
nao.horiguchi, muchun.song, mhocko, lorenzo.stoakes, linmiaohe,
liam.howlett, jiaqiyan, david, jane.chu, akpm
The patch titled
Subject: mm/memory-failure: fix missing ->mf_stats count in hugetlb poison
has been added to the -mm mm-hotfixes-unstable branch. Its filename is
mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison.patch
This patch will later appear in the mm-hotfixes-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via various
branches at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there most days
------------------------------------------------------
From: Jane Chu <jane.chu@oracle.com>
Subject: mm/memory-failure: fix missing ->mf_stats count in hugetlb poison
Date: Fri, 16 Jan 2026 13:38:32 -0700
When a newly poisoned subpage ends up in an already poisoned hugetlb
folio, 'num_poisoned_pages' is incremented, but the per node ->mf_stats is
not. Fix the inconsistency by designating action_result() to update them
both.
While at it, define __get_huge_page_for_hwpoison() return values in terms
of symbol names for better readibility. Also rename
folio_set_hugetlb_hwpoison() to hugetlb_update_hwpoison() since the
function does more than the conventional bit setting and the fact three
possible return values are expected.
Link: https://lkml.kernel.org/r/20260116203834.3179551-1-jane.chu@oracle.com
Fixes: 18f41fa616ee ("mm: memory-failure: bump memory failure stats to pglist_data")
Signed-off-by: Jane Chu <jane.chu@oracle.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Jiaqi Yan <jiaqiyan@google.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
mm/memory-failure.c | 91 ++++++++++++++++++++++++------------------
1 file changed, 54 insertions(+), 37 deletions(-)
--- a/mm/memory-failure.c~mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison
+++ a/mm/memory-failure.c
@@ -1883,12 +1883,22 @@ static unsigned long __folio_free_raw_hw
return count;
}
-static int folio_set_hugetlb_hwpoison(struct folio *folio, struct page *page)
+#define MF_HUGETLB_FREED 0 /* freed hugepage */
+#define MF_HUGETLB_IN_USED 1 /* in-use hugepage */
+#define MF_HUGETLB_NON_HUGEPAGE 2 /* not a hugepage */
+#define MF_HUGETLB_FOLIO_PRE_POISONED 3 /* folio already poisoned */
+#define MF_HUGETLB_PAGE_PRE_POISONED 4 /* exact page already poisoned */
+#define MF_HUGETLB_RETRY 5 /* hugepage is busy, retry */
+/*
+ * Set hugetlb folio as hwpoisoned, update folio private raw hwpoison list
+ * to keep track of the poisoned pages.
+ */
+static int hugetlb_update_hwpoison(struct folio *folio, struct page *page)
{
struct llist_head *head;
struct raw_hwp_page *raw_hwp;
struct raw_hwp_page *p;
- int ret = folio_test_set_hwpoison(folio) ? -EHWPOISON : 0;
+ int ret = folio_test_set_hwpoison(folio) ? MF_HUGETLB_FOLIO_PRE_POISONED : 0;
/*
* Once the hwpoison hugepage has lost reliable raw error info,
@@ -1896,20 +1906,17 @@ static int folio_set_hugetlb_hwpoison(st
* so skip to add additional raw error info.
*/
if (folio_test_hugetlb_raw_hwp_unreliable(folio))
- return -EHWPOISON;
+ return MF_HUGETLB_FOLIO_PRE_POISONED;
head = raw_hwp_list_head(folio);
llist_for_each_entry(p, head->first, node) {
if (p->page == page)
- return -EHWPOISON;
+ return MF_HUGETLB_PAGE_PRE_POISONED;
}
raw_hwp = kmalloc(sizeof(struct raw_hwp_page), GFP_ATOMIC);
if (raw_hwp) {
raw_hwp->page = page;
llist_add(&raw_hwp->node, head);
- /* the first error event will be counted in action_result(). */
- if (ret)
- num_poisoned_pages_inc(page_to_pfn(page));
} else {
/*
* Failed to save raw error info. We no longer trace all
@@ -1957,42 +1964,38 @@ void folio_clear_hugetlb_hwpoison(struct
/*
* Called from hugetlb code with hugetlb_lock held.
- *
- * Return values:
- * 0 - free hugepage
- * 1 - in-use hugepage
- * 2 - not a hugepage
- * -EBUSY - the hugepage is busy (try to retry)
- * -EHWPOISON - the hugepage is already hwpoisoned
*/
int __get_huge_page_for_hwpoison(unsigned long pfn, int flags,
bool *migratable_cleared)
{
struct page *page = pfn_to_page(pfn);
struct folio *folio = page_folio(page);
- int ret = 2; /* fallback to normal page handling */
bool count_increased = false;
+ int ret, rc;
- if (!folio_test_hugetlb(folio))
+ if (!folio_test_hugetlb(folio)) {
+ ret = MF_HUGETLB_NON_HUGEPAGE;
goto out;
-
- if (flags & MF_COUNT_INCREASED) {
- ret = 1;
+ } else if (flags & MF_COUNT_INCREASED) {
+ ret = MF_HUGETLB_IN_USED;
count_increased = true;
} else if (folio_test_hugetlb_freed(folio)) {
- ret = 0;
+ ret = MF_HUGETLB_FREED;
} else if (folio_test_hugetlb_migratable(folio)) {
- ret = folio_try_get(folio);
- if (ret)
+ if (folio_try_get(folio)) {
+ ret = MF_HUGETLB_IN_USED;
count_increased = true;
+ } else
+ ret = MF_HUGETLB_FREED;
} else {
- ret = -EBUSY;
+ ret = MF_HUGETLB_RETRY;
if (!(flags & MF_NO_RETRY))
goto out;
}
- if (folio_set_hugetlb_hwpoison(folio, page)) {
- ret = -EHWPOISON;
+ rc = hugetlb_update_hwpoison(folio, page);
+ if (rc >= MF_HUGETLB_FOLIO_PRE_POISONED) {
+ ret = rc;
goto out;
}
@@ -2017,10 +2020,15 @@ out:
* with basic operations like hugepage allocation/free/demotion.
* So some of prechecks for hwpoison (pinning, and testing/setting
* PageHWPoison) should be done in single hugetlb_lock range.
+ * Returns:
+ * 0 - not hugetlb, or recovered
+ * -EBUSY - not recovered
+ * -EOPNOTSUPP - hwpoison_filter'ed
+ * -EHWPOISON - folio or exact page already poisoned
*/
static int try_memory_failure_hugetlb(unsigned long pfn, int flags, int *hugetlb)
{
- int res;
+ int res, rv;
struct page *p = pfn_to_page(pfn);
struct folio *folio;
unsigned long page_flags;
@@ -2029,22 +2037,31 @@ static int try_memory_failure_hugetlb(un
*hugetlb = 1;
retry:
res = get_huge_page_for_hwpoison(pfn, flags, &migratable_cleared);
- if (res == 2) { /* fallback to normal page handling */
+ switch (res) {
+ case MF_HUGETLB_NON_HUGEPAGE: /* fallback to normal page handling */
*hugetlb = 0;
return 0;
- } else if (res == -EHWPOISON) {
- if (flags & MF_ACTION_REQUIRED) {
- folio = page_folio(p);
- res = kill_accessing_process(current, folio_pfn(folio), flags);
- }
- action_result(pfn, MF_MSG_ALREADY_POISONED, MF_FAILED);
- return res;
- } else if (res == -EBUSY) {
+ case MF_HUGETLB_RETRY:
if (!(flags & MF_NO_RETRY)) {
flags |= MF_NO_RETRY;
goto retry;
}
return action_result(pfn, MF_MSG_GET_HWPOISON, MF_IGNORED);
+ case MF_HUGETLB_FOLIO_PRE_POISONED:
+ case MF_HUGETLB_PAGE_PRE_POISONED:
+ rv = -EHWPOISON;
+ if (flags & MF_ACTION_REQUIRED) {
+ folio = page_folio(p);
+ rv = kill_accessing_process(current, folio_pfn(folio), flags);
+ }
+ if (res == MF_HUGETLB_PAGE_PRE_POISONED)
+ action_result(pfn, MF_MSG_ALREADY_POISONED, MF_FAILED);
+ else
+ action_result(pfn, MF_MSG_HUGE, MF_FAILED);
+ return rv;
+ default:
+ WARN_ON((res != MF_HUGETLB_FREED) && (res != MF_HUGETLB_IN_USED));
+ break;
}
folio = page_folio(p);
@@ -2055,7 +2072,7 @@ retry:
if (migratable_cleared)
folio_set_hugetlb_migratable(folio);
folio_unlock(folio);
- if (res == 1)
+ if (res == MF_HUGETLB_IN_USED)
folio_put(folio);
return -EOPNOTSUPP;
}
@@ -2064,7 +2081,7 @@ retry:
* Handling free hugepage. The possible race with hugepage allocation
* or demotion can be prevented by PageHWPoison flag.
*/
- if (res == 0) {
+ if (res == MF_HUGETLB_FREED) {
folio_unlock(folio);
if (__page_handle_poison(p) > 0) {
page_ref_inc(p);
_
Patches currently in -mm which might be from jane.chu@oracle.com are
mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison.patch
mm-memory-failure-teach-kill_accessing_process-to-accept-hugetlb-tail-page-pfn.patch
^ permalink raw reply [flat|nested] 6+ messages in thread
* + mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison.patch added to mm-hotfixes-unstable branch
@ 2026-01-21 0:45 Andrew Morton
0 siblings, 0 replies; 6+ messages in thread
From: Andrew Morton @ 2026-01-21 0:45 UTC (permalink / raw)
To: mm-commits, willy, william.roche, surenb, stable, rppt, rientjes,
osalvador, nao.horiguchi, muchun.song, mhocko, lorenzo.stoakes,
linmiaohe, Liam.Howlett, jiaqiyan, david, clm, jane.chu, akpm
The patch titled
Subject: mm/memory-failure: fix missing ->mf_stats count in hugetlb poison
has been added to the -mm mm-hotfixes-unstable branch. Its filename is
mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison.patch
This patch will later appear in the mm-hotfixes-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via various
branches at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there most days
------------------------------------------------------
From: Jane Chu <jane.chu@oracle.com>
Subject: mm/memory-failure: fix missing ->mf_stats count in hugetlb poison
Date: Tue, 20 Jan 2026 16:22:33 -0700
When a newly poisoned subpage ends up in an already poisoned hugetlb
folio, 'num_poisoned_pages' is incremented, but the per node ->mf_stats is
not. Fix the inconsistency by designating action_result() to update them
both.
While at it, define __get_huge_page_for_hwpoison() return values in terms
of symbol names for better readibility. Also rename
folio_set_hugetlb_hwpoison() to hugetlb_update_hwpoison() since the
function does more than the conventional bit setting and the fact three
possible return values are expected.
Link: https://lkml.kernel.org/r/20260120232234.3462258-1-jane.chu@oracle.com
Fixes: 18f41fa616ee ("mm: memory-failure: bump memory failure stats to pglist_data")
Signed-off-by: Jane Chu <jane.chu@oracle.com>
Acked-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: <stable@vger.kernel.org>
Cc: Chris Mason <clm@meta.com>
Cc: David Hildenbrand <david@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Jiaqi Yan <jiaqiyan@google.com>
Cc: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Naoya Horiguchi <nao.horiguchi@gmail.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: William Roche <william.roche@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
mm/memory-failure.c | 93 +++++++++++++++++++++++++-----------------
1 file changed, 56 insertions(+), 37 deletions(-)
--- a/mm/memory-failure.c~mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison
+++ a/mm/memory-failure.c
@@ -1883,12 +1883,22 @@ static unsigned long __folio_free_raw_hw
return count;
}
-static int folio_set_hugetlb_hwpoison(struct folio *folio, struct page *page)
+#define MF_HUGETLB_FREED 0 /* freed hugepage */
+#define MF_HUGETLB_IN_USED 1 /* in-use hugepage */
+#define MF_HUGETLB_NON_HUGEPAGE 2 /* not a hugepage */
+#define MF_HUGETLB_FOLIO_PRE_POISONED 3 /* folio already poisoned */
+#define MF_HUGETLB_PAGE_PRE_POISONED 4 /* exact page already poisoned */
+#define MF_HUGETLB_RETRY 5 /* hugepage is busy, retry */
+/*
+ * Set hugetlb folio as hwpoisoned, update folio private raw hwpoison list
+ * to keep track of the poisoned pages.
+ */
+static int hugetlb_update_hwpoison(struct folio *folio, struct page *page)
{
struct llist_head *head;
struct raw_hwp_page *raw_hwp;
struct raw_hwp_page *p;
- int ret = folio_test_set_hwpoison(folio) ? -EHWPOISON : 0;
+ int ret = folio_test_set_hwpoison(folio) ? MF_HUGETLB_FOLIO_PRE_POISONED : 0;
/*
* Once the hwpoison hugepage has lost reliable raw error info,
@@ -1896,20 +1906,17 @@ static int folio_set_hugetlb_hwpoison(st
* so skip to add additional raw error info.
*/
if (folio_test_hugetlb_raw_hwp_unreliable(folio))
- return -EHWPOISON;
+ return MF_HUGETLB_FOLIO_PRE_POISONED;
head = raw_hwp_list_head(folio);
llist_for_each_entry(p, head->first, node) {
if (p->page == page)
- return -EHWPOISON;
+ return MF_HUGETLB_PAGE_PRE_POISONED;
}
raw_hwp = kmalloc(sizeof(struct raw_hwp_page), GFP_ATOMIC);
if (raw_hwp) {
raw_hwp->page = page;
llist_add(&raw_hwp->node, head);
- /* the first error event will be counted in action_result(). */
- if (ret)
- num_poisoned_pages_inc(page_to_pfn(page));
} else {
/*
* Failed to save raw error info. We no longer trace all
@@ -1957,42 +1964,39 @@ void folio_clear_hugetlb_hwpoison(struct
/*
* Called from hugetlb code with hugetlb_lock held.
- *
- * Return values:
- * 0 - free hugepage
- * 1 - in-use hugepage
- * 2 - not a hugepage
- * -EBUSY - the hugepage is busy (try to retry)
- * -EHWPOISON - the hugepage is already hwpoisoned
*/
int __get_huge_page_for_hwpoison(unsigned long pfn, int flags,
bool *migratable_cleared)
{
struct page *page = pfn_to_page(pfn);
struct folio *folio = page_folio(page);
- int ret = 2; /* fallback to normal page handling */
bool count_increased = false;
+ int ret, rc;
- if (!folio_test_hugetlb(folio))
+ if (!folio_test_hugetlb(folio)) {
+ ret = MF_HUGETLB_NON_HUGEPAGE;
goto out;
-
- if (flags & MF_COUNT_INCREASED) {
- ret = 1;
+ } else if (flags & MF_COUNT_INCREASED) {
+ ret = MF_HUGETLB_IN_USED;
count_increased = true;
} else if (folio_test_hugetlb_freed(folio)) {
- ret = 0;
+ ret = MF_HUGETLB_FREED;
} else if (folio_test_hugetlb_migratable(folio)) {
- ret = folio_try_get(folio);
- if (ret)
+ if (folio_try_get(folio)) {
+ ret = MF_HUGETLB_IN_USED;
count_increased = true;
+ } else {
+ ret = MF_HUGETLB_FREED;
+ }
} else {
- ret = -EBUSY;
+ ret = MF_HUGETLB_RETRY;
if (!(flags & MF_NO_RETRY))
goto out;
}
- if (folio_set_hugetlb_hwpoison(folio, page)) {
- ret = -EHWPOISON;
+ rc = hugetlb_update_hwpoison(folio, page);
+ if (rc >= MF_HUGETLB_FOLIO_PRE_POISONED) {
+ ret = rc;
goto out;
}
@@ -2017,10 +2021,16 @@ out:
* with basic operations like hugepage allocation/free/demotion.
* So some of prechecks for hwpoison (pinning, and testing/setting
* PageHWPoison) should be done in single hugetlb_lock range.
+ * Returns:
+ * 0 - not hugetlb, or recovered
+ * -EBUSY - not recovered
+ * -EOPNOTSUPP - hwpoison_filter'ed
+ * -EHWPOISON - folio or exact page already poisoned
+ * -EFAULT - kill_accessing_process finds current->mm null
*/
static int try_memory_failure_hugetlb(unsigned long pfn, int flags, int *hugetlb)
{
- int res;
+ int res, rv;
struct page *p = pfn_to_page(pfn);
struct folio *folio;
unsigned long page_flags;
@@ -2029,22 +2039,31 @@ static int try_memory_failure_hugetlb(un
*hugetlb = 1;
retry:
res = get_huge_page_for_hwpoison(pfn, flags, &migratable_cleared);
- if (res == 2) { /* fallback to normal page handling */
+ switch (res) {
+ case MF_HUGETLB_NON_HUGEPAGE: /* fallback to normal page handling */
*hugetlb = 0;
return 0;
- } else if (res == -EHWPOISON) {
- if (flags & MF_ACTION_REQUIRED) {
- folio = page_folio(p);
- res = kill_accessing_process(current, folio_pfn(folio), flags);
- }
- action_result(pfn, MF_MSG_ALREADY_POISONED, MF_FAILED);
- return res;
- } else if (res == -EBUSY) {
+ case MF_HUGETLB_RETRY:
if (!(flags & MF_NO_RETRY)) {
flags |= MF_NO_RETRY;
goto retry;
}
return action_result(pfn, MF_MSG_GET_HWPOISON, MF_IGNORED);
+ case MF_HUGETLB_FOLIO_PRE_POISONED:
+ case MF_HUGETLB_PAGE_PRE_POISONED:
+ rv = -EHWPOISON;
+ if (flags & MF_ACTION_REQUIRED) {
+ folio = page_folio(p);
+ rv = kill_accessing_process(current, folio_pfn(folio), flags);
+ }
+ if (res == MF_HUGETLB_PAGE_PRE_POISONED)
+ action_result(pfn, MF_MSG_ALREADY_POISONED, MF_FAILED);
+ else
+ action_result(pfn, MF_MSG_HUGE, MF_FAILED);
+ return rv;
+ default:
+ WARN_ON((res != MF_HUGETLB_FREED) && (res != MF_HUGETLB_IN_USED));
+ break;
}
folio = page_folio(p);
@@ -2055,7 +2074,7 @@ retry:
if (migratable_cleared)
folio_set_hugetlb_migratable(folio);
folio_unlock(folio);
- if (res == 1)
+ if (res == MF_HUGETLB_IN_USED)
folio_put(folio);
return -EOPNOTSUPP;
}
@@ -2064,7 +2083,7 @@ retry:
* Handling free hugepage. The possible race with hugepage allocation
* or demotion can be prevented by PageHWPoison flag.
*/
- if (res == 0) {
+ if (res == MF_HUGETLB_FREED) {
folio_unlock(folio);
if (__page_handle_poison(p) > 0) {
page_ref_inc(p);
_
Patches currently in -mm which might be from jane.chu@oracle.com are
mm-memory-failure-fix-missing-mf_stats-count-in-hugetlb-poison.patch
mm-memory-failure-teach-kill_accessing_process-to-accept-hugetlb-tail-page-pfn.patch
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