| Message ID | 20201013144447.6706-2-osalvador@suse.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | HWpoison: further fixes and cleanups | expand |
On 10/13/20 4:44 PM, Oscar Salvador wrote: > A page with 0-refcount and !PageBuddy could perfectly be a pcppage. > Currently, we bail out with an error if we encounter such a page, meaning > that we do not handle pcppages neither from hard-offline nor from > soft-offline path. > > Fix this by draining pcplists whenever we find this kind of page and retry > the check again. It might be that pcplists have been spilled into the > buddy allocator and so we can handle it. > > Signed-off-by: Oscar Salvador <osalvador@suse.de> > Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> > --- > mm/memory-failure.c | 24 ++++++++++++++++++++++-- > 1 file changed, 22 insertions(+), 2 deletions(-) > > diff --git a/mm/memory-failure.c b/mm/memory-failure.c > index c0bb186bba62..e2f12410c594 100644 > --- a/mm/memory-failure.c > +++ b/mm/memory-failure.c > @@ -946,13 +946,13 @@ static int page_action(struct page_state *ps, struct page *p, > } > > /** > - * get_hwpoison_page() - Get refcount for memory error handling: > + * __get_hwpoison_page() - Get refcount for memory error handling: > * @page: raw error page (hit by memory error) > * > * Return: return 0 if failed to grab the refcount, otherwise true (some > * non-zero value.) > */ > -static int get_hwpoison_page(struct page *page) > +static int __get_hwpoison_page(struct page *page) > { > struct page *head = compound_head(page); > > @@ -982,6 +982,26 @@ static int get_hwpoison_page(struct page *page) > return 0; > } > > +static int get_hwpoison_page(struct page *p) > +{ > + int ret; > + bool drained = false; > + > +retry: > + ret = __get_hwpoison_page(p); > + if (!ret && !is_free_buddy_page(p) && !page_count(p) && !drained) { > + /* > + * The page might be in a pcplist, so try to drain those > + * and see if we are lucky. > + */ > + drain_all_pages(page_zone(p)); > + drained = true; > + goto retry; > + } > + > + return ret; > +} > + > /* > * Do all that is necessary to remove user space mappings. Unmap > * the pages and send SIGBUS to the processes if the data was dirty. >
diff --git a/mm/memory-failure.c b/mm/memory-failure.c index c0bb186bba62..e2f12410c594 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -946,13 +946,13 @@ static int page_action(struct page_state *ps, struct page *p, } /** - * get_hwpoison_page() - Get refcount for memory error handling: + * __get_hwpoison_page() - Get refcount for memory error handling: * @page: raw error page (hit by memory error) * * Return: return 0 if failed to grab the refcount, otherwise true (some * non-zero value.) */ -static int get_hwpoison_page(struct page *page) +static int __get_hwpoison_page(struct page *page) { struct page *head = compound_head(page); @@ -982,6 +982,26 @@ static int get_hwpoison_page(struct page *page) return 0; } +static int get_hwpoison_page(struct page *p) +{ + int ret; + bool drained = false; + +retry: + ret = __get_hwpoison_page(p); + if (!ret && !is_free_buddy_page(p) && !page_count(p) && !drained) { + /* + * The page might be in a pcplist, so try to drain those + * and see if we are lucky. + */ + drain_all_pages(page_zone(p)); + drained = true; + goto retry; + } + + return ret; +} + /* * Do all that is necessary to remove user space mappings. Unmap * the pages and send SIGBUS to the processes if the data was dirty.