mirror of
https://github.com/torvalds/linux
synced 2024-09-06 18:01:05 +00:00
mm: memory-failure: fix potential unexpected return value from unpoison_memory()
If unpoison_memory() fails to clear page hwpoisoned flag, return value ret
is expected to be -EBUSY. But when get_hwpoison_page() returns 1 and
fails to clear page hwpoisoned flag due to races, return value will be
unexpected 1 leading to users being confused. And there's a code smell
that the variable "ret" is used not only to save the return value of
unpoison_memory(), but also the return value from get_hwpoison_page().
Make a further cleanup by using another auto-variable solely to save the
return value of get_hwpoison_page() as suggested by Naoya.
Link: https://lkml.kernel.org/r/20230727115643.639741-3-linmiaohe@huawei.com
Fixes: bf181c5825
("mm/hwpoison: fix unpoison_memory()")
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
parent
f985fc3220
commit
f29623e4a5
|
@ -2466,7 +2466,7 @@ int unpoison_memory(unsigned long pfn)
|
|||
{
|
||||
struct folio *folio;
|
||||
struct page *p;
|
||||
int ret = -EBUSY;
|
||||
int ret = -EBUSY, ghp;
|
||||
unsigned long count = 1;
|
||||
bool huge = false;
|
||||
static DEFINE_RATELIMIT_STATE(unpoison_rs, DEFAULT_RATELIMIT_INTERVAL,
|
||||
|
@ -2514,29 +2514,28 @@ int unpoison_memory(unsigned long pfn)
|
|||
if (folio_test_slab(folio) || PageTable(&folio->page) || folio_test_reserved(folio))
|
||||
goto unlock_mutex;
|
||||
|
||||
ret = get_hwpoison_page(p, MF_UNPOISON);
|
||||
if (!ret) {
|
||||
ghp = get_hwpoison_page(p, MF_UNPOISON);
|
||||
if (!ghp) {
|
||||
if (PageHuge(p)) {
|
||||
huge = true;
|
||||
count = folio_free_raw_hwp(folio, false);
|
||||
if (count == 0) {
|
||||
ret = -EBUSY;
|
||||
if (count == 0)
|
||||
goto unlock_mutex;
|
||||
}
|
||||
}
|
||||
ret = folio_test_clear_hwpoison(folio) ? 0 : -EBUSY;
|
||||
} else if (ret < 0) {
|
||||
if (ret == -EHWPOISON) {
|
||||
} else if (ghp < 0) {
|
||||
if (ghp == -EHWPOISON) {
|
||||
ret = put_page_back_buddy(p) ? 0 : -EBUSY;
|
||||
} else
|
||||
} else {
|
||||
ret = ghp;
|
||||
unpoison_pr_info("Unpoison: failed to grab page %#lx\n",
|
||||
pfn, &unpoison_rs);
|
||||
}
|
||||
} else {
|
||||
if (PageHuge(p)) {
|
||||
huge = true;
|
||||
count = folio_free_raw_hwp(folio, false);
|
||||
if (count == 0) {
|
||||
ret = -EBUSY;
|
||||
folio_put(folio);
|
||||
goto unlock_mutex;
|
||||
}
|
||||
|
|
Loading…
Reference in a new issue