BUG at mm/page_alloc.c:1913
VM_BUG_ON(page_zone(start_page) != page_zone(end_page));
Commit b92df1de5d28 ("mm: page_alloc: skip over regions of invalid pfns where possible") introduced a bug where move_freepages() triggers a VM_BUG_ON() on uninitialized page structure due to pageblock alignment. To fix this, simply align the skipped pfns in memmap_init_zone() the same way as in move_freepages_block().
Fixes: b92df1de5d28 ("mm: page_alloc: skip over regions of invalid pfns where possible") Signed-off-by: Daniel Vacek neelx@redhat.com Cc: stable@vger.kernel.org --- mm/memblock.c | 13 ++++++------- mm/page_alloc.c | 9 +++++++-- 2 files changed, 13 insertions(+), 9 deletions(-)
diff --git a/mm/memblock.c b/mm/memblock.c index 5a9ca2a1751b..2a5facd236bb 100644 --- a/mm/memblock.c +++ b/mm/memblock.c @@ -1101,13 +1101,12 @@ void __init_memblock __next_mem_pfn_range(int *idx, int nid, *out_nid = r->nid; }
-unsigned long __init_memblock memblock_next_valid_pfn(unsigned long pfn, - unsigned long max_pfn) +unsigned long __init_memblock memblock_next_valid_pfn(unsigned long pfn) { struct memblock_type *type = &memblock.memory; unsigned int right = type->cnt; unsigned int mid, left = 0; - phys_addr_t addr = PFN_PHYS(pfn + 1); + phys_addr_t addr = PFN_PHYS(++pfn);
do { mid = (right + left) / 2; @@ -1118,15 +1117,15 @@ unsigned long __init_memblock memblock_next_valid_pfn(unsigned long pfn, type->regions[mid].size)) left = mid + 1; else { - /* addr is within the region, so pfn + 1 is valid */ - return min(pfn + 1, max_pfn); + /* addr is within the region, so pfn is valid */ + return pfn; } } while (left < right);
if (right == type->cnt) - return max_pfn; + return -1UL; else - return min(PHYS_PFN(type->regions[right].base), max_pfn); + return PHYS_PFN(type->regions[right].base); }
/** diff --git a/mm/page_alloc.c b/mm/page_alloc.c index cb416723538f..eb27ccb50928 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -5359,9 +5359,14 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone, /* * Skip to the pfn preceding the next valid one (or * end_pfn), such that we hit a valid pfn (or end_pfn) - * on our next iteration of the loop. + * on our next iteration of the loop. Note that it needs + * to be pageblock aligned even when the region itself + * is not as move_freepages_block() can shift ahead of + * the valid region but still depends on correct page + * metadata. */ - pfn = memblock_next_valid_pfn(pfn, end_pfn) - 1; + pfn = (memblock_next_valid_pfn(pfn) & + ~(pageblock_nr_pages-1)) - 1; #endif continue; }