| Message ID | 20230406082004.2185420-1-naoya.horiguchi@linux.dev (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [v1] mm/huge_memory.c: warn with pr_warn_ratelimited instead of VM_WARN_ON_ONCE_FOLIO | expand |
On Thu, Apr 6, 2023 at 1:20 AM Naoya Horiguchi <naoya.horiguchi@linux.dev> wrote: > > From: Naoya Horiguchi <naoya.horiguchi@nec.com> > > split_huge_page_to_list() WARNs when called for huge zero pages, which > sounds to me too harsh because it does not imply a kernel bug, but just > notifies the event to admins. On the other hand, this is considered > as critical by syzkaller and makes its testing less efficient, which > seems to me harmful. > > So replace the VM_WARN_ON_ONCE_FOLIO with pr_warn_ratelimited. Makes sense to me. Reviewed-by: Yang Shi <shy828301@gmail.com> > > Fixes: 478d134e9506 ("mm/huge_memory: do not overkill when splitting huge_zero_page") > Reported-by: syzbot+07a218429c8d19b1fb25@syzkaller.appspotmail.com > Link: https://lore.kernel.org/lkml/000000000000a6f34a05e6efcd01@google.com/ > Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com> > Cc: stable@vger.kernel.org > --- > mm/huge_memory.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/mm/huge_memory.c b/mm/huge_memory.c > index 81a5689806af..06bcdd6f5060 100644 > --- a/mm/huge_memory.c > +++ b/mm/huge_memory.c > @@ -2649,9 +2649,10 @@ int split_huge_page_to_list(struct page *page, struct list_head *list) > VM_BUG_ON_FOLIO(!folio_test_large(folio), folio); > > is_hzp = is_huge_zero_page(&folio->page); > - VM_WARN_ON_ONCE_FOLIO(is_hzp, folio); > - if (is_hzp) > + if (is_hzp) { > + pr_warn_ratelimited("Called split_huge_page for huge zero page\n"); > return -EBUSY; > + } > > if (folio_test_writeback(folio)) > return -EBUSY; > -- > 2.25.1 >
diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 81a5689806af..06bcdd6f5060 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -2649,9 +2649,10 @@ int split_huge_page_to_list(struct page *page, struct list_head *list) VM_BUG_ON_FOLIO(!folio_test_large(folio), folio); is_hzp = is_huge_zero_page(&folio->page); - VM_WARN_ON_ONCE_FOLIO(is_hzp, folio); - if (is_hzp) + if (is_hzp) { + pr_warn_ratelimited("Called split_huge_page for huge zero page\n"); return -EBUSY; + } if (folio_test_writeback(folio)) return -EBUSY;