From: Mike Rapoport <rppt@xxxxxxxxxxxxx> The memory reserved by console/PALcode or non-volatile memory is not added to memblock.memory. Since commit fa3354e4ea39 (mm: free_area_init: use maximal zone PFNs rather than zone sizes) the initialization of the memory map relies on the accuracy of memblock.memory to properly calculate zone sizes. The holes in memblock.memory caused by absent regions reserved by the firmware cause incorrect initialization of struct pages which leads to BUG() during the initial page freeing: BUG: Bad page state in process swapper pfn:2ffc53 page:fffffc000ecf14c0 refcount:0 mapcount:1 mapping:0000000000000000 index:0x0 flags: 0x0() raw: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 raw: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 page dumped because: nonzero mapcount Modules linked in: CPU: 0 PID: 0 Comm: swapper Not tainted 5.7.0-03841-gfa3354e4ea39-dirty #26 fffffc0001b5bd68 fffffc0001b5be80 fffffc00011cd148 fffffc000ecf14c0 fffffc00019803df fffffc0001b5be80 fffffc00011ce340 fffffc000ecf14c0 0000000000000000 fffffc0001b5be80 fffffc0001b482c0 fffffc00027d6618 fffffc00027da7d0 00000000002ff97a 0000000000000000 fffffc0001b5be80 fffffc00011d1abc fffffc000ecf14c0 fffffc0002d00000 fffffc0001b5be80 fffffc0001b2350c 0000000000300000 fffffc0001b48298 fffffc0001b482c0 Trace: [<fffffc00011cd148>] bad_page+0x168/0x1b0 [<fffffc00011ce340>] free_pcp_prepare+0x1e0/0x290 [<fffffc00011d1abc>] free_unref_page+0x2c/0xa0 [<fffffc00014ee5f0>] cmp_ex_sort+0x0/0x30 [<fffffc00014ee5f0>] cmp_ex_sort+0x0/0x30 [<fffffc000101001c>] _stext+0x1c/0x20 Fix this by registering the reserved ranges in memblock.memory. Link: https://lore.kernel.org/lkml/20210726192311.uffqnanxw3ac5wwi@ivybridge Fixes: fa3354e4ea39 ("mm: free_area_init: use maximal zone PFNs rather than zone sizes") Reported-by: Matt Turner <mattst88@xxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Mike Rapoport <rppt@xxxxxxxxxxxxx> --- arch/alpha/kernel/setup.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/arch/alpha/kernel/setup.c b/arch/alpha/kernel/setup.c index 7d56c217b235..b4fbbba30aa2 100644 --- a/arch/alpha/kernel/setup.c +++ b/arch/alpha/kernel/setup.c @@ -319,18 +319,19 @@ setup_memory(void *kernel_end) i, cluster->usage, cluster->start_pfn, cluster->start_pfn + cluster->numpages); - /* Bit 0 is console/PALcode reserved. Bit 1 is - non-volatile memory -- we might want to mark - this for later. */ - if (cluster->usage & 3) - continue; - end = cluster->start_pfn + cluster->numpages; if (end > max_low_pfn) max_low_pfn = end; memblock_add(PFN_PHYS(cluster->start_pfn), cluster->numpages << PAGE_SHIFT); + + /* Bit 0 is console/PALcode reserved. Bit 1 is + non-volatile memory -- we might want to mark + this for later. */ + if (cluster->usage & 3) + memblock_reserve(PFN_PHYS(cluster->start_pfn), + cluster->numpages << PAGE_SHIFT); } /* base-commit: d8079fac168168b25677dc16c00ffaf9fb7df723 -- 2.28.0