On Fri, 26 Aug 2022 09:40:52 +0200 Michal Hocko <mhocko@xxxxxxxx> wrote: > > Changes in V5: > > o Used the loop variable name as ext_put_continue -- David > > If this is the only change since the last version (I didn't have much > time to read through the whole patch) then my ack still applies. yup. --- a/mm/page_owner.c~mm-fix-use-after-free-of-page_ext-after-race-with-memory-offline-v5 +++ a/mm/page_owner.c @@ -326,7 +326,7 @@ void pagetypeinfo_showmixedcount_print(s continue; if (!test_bit(PAGE_EXT_OWNER_ALLOCATED, &page_ext->flags)) - goto loop; + goto ext_put_continue; page_owner = get_page_owner(page_ext); page_mt = gfp_migratetype(page_owner->gfp_mask); @@ -341,7 +341,7 @@ void pagetypeinfo_showmixedcount_print(s break; } pfn += (1UL << page_owner->order) - 1; -loop: +ext_put_continue: page_ext_put(page_ext); } } @@ -561,14 +561,14 @@ read_page_owner(struct file *file, char * because we don't hold the zone lock. */ if (!test_bit(PAGE_EXT_OWNER, &page_ext->flags)) - goto loop; + goto ext_put_continue; /* * Although we do have the info about past allocation of free * pages, it's not relevant for current memory usage. */ if (!test_bit(PAGE_EXT_OWNER_ALLOCATED, &page_ext->flags)) - goto loop; + goto ext_put_continue; page_owner = get_page_owner(page_ext); @@ -577,7 +577,7 @@ read_page_owner(struct file *file, char * would inflate the stats. */ if (!IS_ALIGNED(pfn, 1 << page_owner->order)) - goto loop; + goto ext_put_continue; /* * Access to page_ext->handle isn't synchronous so we should @@ -585,7 +585,7 @@ read_page_owner(struct file *file, char */ handle = READ_ONCE(page_owner->handle); if (!handle) - goto loop; + goto ext_put_continue; /* Record the next PFN to read in the file offset */ *ppos = (pfn - min_low_pfn) + 1; @@ -594,7 +594,7 @@ read_page_owner(struct file *file, char page_ext_put(page_ext); return print_page_owner(buf, count, pfn, page, &page_owner_tmp, handle); -loop: +ext_put_continue: page_ext_put(page_ext); } @@ -654,13 +654,13 @@ static void init_pages_in_zone(pg_data_t /* Maybe overlapping zone */ if (test_bit(PAGE_EXT_OWNER, &page_ext->flags)) - goto loop; + goto ext_put_continue; /* Found early allocated page */ __set_page_owner_handle(page_ext, early_handle, 0, 0); count++; -loop: +ext_put_continue: page_ext_put(page_ext); } cond_resched(); _
