From: Jane Chu <jane.chu@xxxxxxxxxx> Subject: mm/memory-failure: unnecessary amount of unmapping It appears that unmap_mapping_range() actually takes a 'size' as its third argument rather than a location, the current calling fashion causes unnecessary amount of unmapping to occur. Link: https://lkml.kernel.org/r/20210420002821.2749748-1-jane.chu@xxxxxxxxxx Fixes: 6100e34b2526e ("mm, memory_failure: Teach memory_failure() about dev_pagemap pages") Signed-off-by: Jane Chu <jane.chu@xxxxxxxxxx> Reviewed-by: Dan Williams <dan.j.williams@xxxxxxxxx> Reviewed-by: Naoya Horiguchi <naoya.horiguchi@xxxxxxx> Cc: Dave Jiang <dave.jiang@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/memory-failure.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/mm/memory-failure.c~mm-memory-failure-unecessary-amount-of-unmapping +++ a/mm/memory-failure.c @@ -1368,7 +1368,7 @@ static int memory_failure_dev_pagemap(un * communicated in siginfo, see kill_proc() */ start = (page->index << PAGE_SHIFT) & ~(size - 1); - unmap_mapping_range(page->mapping, start, start + size, 0); + unmap_mapping_range(page->mapping, start, size, 0); } kill_procs(&tokill, flags & MF_MUST_KILL, !unmap_success, pfn, flags); rc = 0; _