Hi, On Wed, Jul 14, 2021 at 03:37:36PM +0300, Mike Rapoport wrote: > From: Mike Rapoport <rppt@xxxxxxxxxxxxx> > > Currently memory map for the holes is initialized only when SPARSEMEM > memory model is used. Yet, even with FLATMEM there could be holes in the > physical memory layout that have memory map entries. > > For instance, the memory reserved using e820 API on i386 or > "reserved-memory" nodes in device tree would not appear in memblock.memory > and hence the struct pages for such holes will be skipped during memory map > initialization. > > These struct pages will be zeroed because the memory map for FLATMEM > systems is allocated with memblock_alloc_node() that clears the allocated > memory. While zeroed struct pages do not cause immediate problems, the > correct behaviour is to initialize every page using __init_single_page(). > Besides, enabling page poison for FLATMEM case will trigger > PF_POISONED_CHECK() unless the memory map is properly initialized. > > Make sure init_unavailable_range() is called for both SPARSEMEM and FLATMEM > so that struct pages representing memory holes would appear as PG_Reserved > with any memory layout. > > Signed-off-by: Mike Rapoport <rppt@xxxxxxxxxxxxx> This patch causes microblaze petalogix-ml605 qemu emulations to fail silently (no console output). Reverting it fixes the problem. Guenter --- Bisect log: # bad: [8d4b477da1a807199ca60e0829357ce7aa6758d5] Add linux-next specific files for 20210730 # good: [ff1176468d368232b684f75e82563369208bc371] Linux 5.14-rc3 git bisect start 'HEAD' 'v5.14-rc3' # good: [8f3eb1f5c702ef868d89799b03c21d122f2fe197] Merge remote-tracking branch 'bpf-next/for-next' git bisect good 8f3eb1f5c702ef868d89799b03c21d122f2fe197 # good: [32286c7080c56c835f25302c38eebccf41b7b576] Merge remote-tracking branch 'tip/auto-latest' git bisect good 32286c7080c56c835f25302c38eebccf41b7b576 # good: [70c40604c7d393f95171f49717a27bf8e05b5439] Merge remote-tracking branch 'dmaengine/next' git bisect good 70c40604c7d393f95171f49717a27bf8e05b5439 # good: [b038834891b35ec410693028a500f769db132a81] Merge remote-tracking branch 'rust/rust-next' git bisect good b038834891b35ec410693028a500f769db132a81 # bad: [d8f4e506a9ba375110945d75573b3304491e6350] memory-hotplug.rst: complete admin-guide overhaul git bisect bad d8f4e506a9ba375110945d75573b3304491e6350 # good: [bef692dcfb7cdb5c960abfc31e2386a0ff41af54] lazy tlb: shoot lazies, a non-refcounting lazy tlb option git bisect good bef692dcfb7cdb5c960abfc31e2386a0ff41af54 # bad: [5fcd957e2f0dc4cb25a6ee60ebfb1200de09c9d1] mm-migrate-demote-pages-during-reclaim-v11 git bisect bad 5fcd957e2f0dc4cb25a6ee60ebfb1200de09c9d1 # good: [8c2a82ab20eb09d217446989ae209f5ff19a64ac] mm/vmalloc: use batched page requests in bulk-allocator git bisect good 8c2a82ab20eb09d217446989ae209f5ff19a64ac # bad: [c36a5446e29f1461780b06785769b9402522f847] mm/page_alloc.c: fix 'zone_id' may be used uninitialized in this function warning git bisect bad c36a5446e29f1461780b06785769b9402522f847 # good: [05e358c552628e26be3985933bea88e7512414c0] mm/kasan: move kasan.fault to mm/kasan/report.c git bisect good 05e358c552628e26be3985933bea88e7512414c0 # bad: [b467ff7f560908e60ca181658b7ee48e5da94da1] microblaze: simplify pte_alloc_one_kernel() git bisect bad b467ff7f560908e60ca181658b7ee48e5da94da1 # bad: [d2a572bf593a57246827bd79c91fe2ee6b7af1f0] mm/page_alloc: always initialize memory map for the holes git bisect bad d2a572bf593a57246827bd79c91fe2ee6b7af1f0 # first bad commit: [d2a572bf593a57246827bd79c91fe2ee6b7af1f0] mm/page_alloc: always initialize memory map for the holes
