On Sat, Jul 31, 2021 at 09:56:01AM -0700, Guenter Roeck wrote: > 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. It appears that petalogix-ml605 memory starts at 0x50000, but microblaze's pfn_valid does not reject pfns < ARCH_PFN_OFFSET. This should fix the issue: diff --git a/arch/microblaze/include/asm/page.h b/arch/microblaze/include/asm/page.h index ce550978f4fc..4b8b2fa78fc5 100644 --- a/arch/microblaze/include/asm/page.h +++ b/arch/microblaze/include/asm/page.h @@ -112,8 +112,7 @@ extern int page_is_ram(unsigned long pfn); # define page_to_phys(page) (page_to_pfn(page) << PAGE_SHIFT) # define ARCH_PFN_OFFSET (memory_start >> PAGE_SHIFT) -# define pfn_valid(pfn) ((pfn) < (max_mapnr + ARCH_PFN_OFFSET)) - +# define pfn_valid(pfn) ((pfn) >= ARCH_PFN_OFFSET && (pfn) < (max_mapnr + ARCH_PFN_OFFSET)) # endif /* __ASSEMBLY__ */ #define virt_addr_valid(vaddr) (pfn_valid(virt_to_pfn(vaddr))) > 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 -- Sincerely yours, Mike.
