On Tue, Sep 20, 2022 at 08:49:00AM +0800, zhaoyang.huang wrote: > From: Zhaoyang Huang <zhaoyang.huang@xxxxxxxxxx> > > High-order pcp page escaped from checking when both of DEBUG_VM and debug_pagealloc > are all disabled if it allocated again from pcp_list without going to global > free list, which should be introduced by 44042b4498. > > fix:44042b4498 > > Signed-off-by: Zhaoyang Huang <zhaoyang.huang@xxxxxxxxxx> Why is the order check needed? In this case, I think the comment itself was wrong and should be corrected. free_pcp_prepare is called when dealing with a PCP page being freed and these days that may order-0 or high-order pages. Wieh DEBUG_VM disabled, the pages are checked in by bulkfree_pcp_prepare when freeing pages from PCP to the core allocator. Why would just high-order pages be checked in free_pcp_prepare and checked again in bulkfree_pcp_prepare? -- Mel Gorman SUSE Labs
