Re: arm32: panic in move_freepages (Was [PATCH v2 0/4] arm64: drop pfn_valid_within() and simplify pfn_valid())

[Kefeng Wang <wangkefeng.wang@huawei.com>]

On 2021/4/27 14:23, Mike Rapoport wrote:
> On Mon, Apr 26, 2021 at 11:26:38PM +0800, Kefeng Wang wrote:
>> On 2021/4/26 13:20, Mike Rapoport wrote:
>>> On Sun, Apr 25, 2021 at 03:51:56PM +0800, Kefeng Wang wrote:
>>>> On 2021/4/25 15:19, Mike Rapoport wrote:
>>>>
>>>>       On Fri, Apr 23, 2021 at 04:11:16PM +0800, Kefeng Wang wrote:
>>>>
>>>>           I tested this patchset(plus arm32 change, like arm64 does)
>>>>           based on lts 5.10，add some debug log, the useful info shows
>>>>           below, if we enable HOLES_IN_ZONE, no panic, any idea,
>>>>           thanks.
>>>>
>>>>       Are there any changes on top of 5.10 except for pfn_valid() patch?
>>>>       Do you see this panic on 5.10 without the changes?
>>>>
>>>> Yes, there are some BSP support for arm board based on 5.10,
> Is it possible to test 5.12?
>
>>>> with or without your patch will get same panic, the panic pfn=de600
>>>> in the range of [dcc00,de00] which is freed by free_memmap, start_pfn
>>>> = dcc00,  dcc00000 end_pfn = de700, de700000
>>>>
>>>> we see the PC is at PageLRU, same reason like arm64 panic log,
>>>>
>>>>      "PageBuddy in move_freepages returns false
>>>>       Then we call PageLRU, the macro calls PF_HEAD which is compound_page()
>>>>       compound_page reads page->compound_head, it is 0xffffffffffffffff, so it
>>>>       resturns 0xfffffffffffffffe - and accessing this address causes crash"
>>>>
>>>>       Can you see stack backtrace beyond move_freepages_block?
>>>>
>>>> I do some oom test, so the log is about memory allocate,
>>>>
>>>> [<c02383c8>] (move_freepages_block) from [<c0238668>]
>>>> (steal_suitable_fallback+0x174/0x1f4)
>>>>
>>>> [<c0238668>] (steal_suitable_fallback) from [<c023999c>] (get_page_from_freelist+0x490/0x9a4)
>>> Hmm, this is called with a page from free list, having a page from a freed
>>> part of the memory map passed to steal_suitable_fallback() means that there
>>> is an issue with creation of the free list.
>>>
>>> Can you please add "memblock=debug" to the kernel command line and post the
>>> log?
>> Here is the log,
>>
>> CPU: ARMv7 Processor [413fc090] revision 0 (ARMv7), cr=1ac5387d
>>
>> CPU: PIPT / VIPT nonaliasing data cache, VIPT aliasing instruction cache
>> OF: fdt: Machine model: HISI-CA9
>> memblock_add: [0x80a00000-0x855fffff] early_init_dt_scan_memory+0x11c/0x188
>> memblock_add: [0x86a00000-0x87dfffff] early_init_dt_scan_memory+0x11c/0x188
>> memblock_add: [0x8bd00000-0x8c4fffff] early_init_dt_scan_memory+0x11c/0x188
>> memblock_add: [0x8e300000-0x8ecfffff] early_init_dt_scan_memory+0x11c/0x188
>> memblock_add: [0x90d00000-0xbfffffff] early_init_dt_scan_memory+0x11c/0x188
>> memblock_add: [0xcc000000-0xdc9fffff] early_init_dt_scan_memory+0x11c/0x188
>> memblock_add: [0xe0800000-0xe0bfffff] early_init_dt_scan_memory+0x11c/0x188
>> memblock_add: [0xf5300000-0xf5bfffff] early_init_dt_scan_memory+0x11c/0x188
>> memblock_add: [0xf5c00000-0xf6ffffff] early_init_dt_scan_memory+0x11c/0x188
>> memblock_add: [0xfe100000-0xfebfffff] early_init_dt_scan_memory+0x11c/0x188
>> memblock_add: [0xfec00000-0xffffffff] early_init_dt_scan_memory+0x11c/0x188
>> memblock_add: [0xde700000-0xde9fffff] early_init_dt_scan_memory+0x11c/0x188
>> memblock_add: [0xf4b00000-0xf52fffff] early_init_dt_scan_memory+0x11c/0x188
>> memblock_add: [0xfda00000-0xfe0fffff] early_init_dt_scan_memory+0x11c/0x188
>> memblock_reserve: [0x80a01000-0x80a02d2e] setup_arch+0x68/0x5c4
>> Malformed early option 'vecpage_wrprotect'
>> Memory policy: Data cache writealloc
>> memblock_reserve: [0x80b00000-0x812e8057] arm_memblock_init+0x34/0x14c
>> memblock_reserve: [0x83000000-0x84ffffff] arm_memblock_init+0x100/0x14c
>> memblock_reserve: [0x80a04000-0x80a07fff] arm_memblock_init+0xa0/0x14c
>> memblock_reserve: [0x80a00000-0x80a02fff] hisi_mem_reserve+0x14/0x30
>> MEMBLOCK configuration:
>>   memory size = 0x4c0fffff reserved size = 0x027ef058
>>   memory.cnt  = 0xa
>>   memory[0x0]    [0x80a00000-0x855fffff], 0x04c00000 bytes flags: 0x0
>>   memory[0x1]    [0x86a00000-0x87dfffff], 0x01400000 bytes flags: 0x0
>>   memory[0x2]    [0x8bd00000-0x8c4fffff], 0x00800000 bytes flags: 0x0
>>   memory[0x3]    [0x8e300000-0x8ecfffff], 0x00a00000 bytes flags: 0x0
>>   memory[0x4]    [0x90d00000-0xbfffffff], 0x2f300000 bytes flags: 0x0
>>   memory[0x5]    [0xcc000000-0xdc9fffff], 0x10a00000 bytes flags: 0x0
>>   memory[0x6]    [0xde700000-0xde9fffff], 0x00300000 bytes flags: 0x0
>>   memory[0x7]    [0xe0800000-0xe0bfffff], 0x00400000 bytes flags: 0x0
>>   memory[0x8]    [0xf4b00000-0xf6ffffff], 0x02500000 bytes flags: 0x0
>>   memory[0x9]    [0xfda00000-0xfffffffe], 0x025fffff bytes flags: 0x0
>>   reserved.cnt  = 0x4
>>   reserved[0x0]    [0x80a00000-0x80a02fff], 0x00003000 bytes flags: 0x0
>>   reserved[0x1]    [0x80a04000-0x80a07fff], 0x00004000 bytes flags: 0x0
>>   reserved[0x2]    [0x80b00000-0x812e8057], 0x007e8058 bytes flags: 0x0
>>   reserved[0x3]    [0x83000000-0x84ffffff], 0x02000000 bytes flags: 0x0
> ...
>> Zone ranges:
>>    Normal   [mem 0x0000000080a00000-0x00000000b01fffff]
>>    HighMem  [mem 0x00000000b0200000-0x00000000ffffefff]
>> Movable zone start for each node
>> Early memory node ranges
>>    node   0: [mem 0x0000000080a00000-0x00000000855fffff]
>>    node   0: [mem 0x0000000086a00000-0x0000000087dfffff]
>>    node   0: [mem 0x000000008bd00000-0x000000008c4fffff]
>>    node   0: [mem 0x000000008e300000-0x000000008ecfffff]
>>    node   0: [mem 0x0000000090d00000-0x00000000bfffffff]
>>    node   0: [mem 0x00000000cc000000-0x00000000dc9fffff]
>>    node   0: [mem 0x00000000de700000-0x00000000de9fffff]
>>    node   0: [mem 0x00000000e0800000-0x00000000e0bfffff]
>>    node   0: [mem 0x00000000f4b00000-0x00000000f6ffffff]
>>    node   0: [mem 0x00000000fda00000-0x00000000ffffefff]
>> Zeroed struct page in unavailable ranges: 513 pages
>> Initmem setup node 0 [mem 0x0000000080a00000-0x00000000ffffefff]
>> On node 0 totalpages: 311551
>>    Normal zone: 1230 pages used for memmap
>>    Normal zone: 0 pages reserved
>>    Normal zone: 157440 pages, LIFO batch:31
>>    HighMem zone: 154111 pages, LIFO batch:31
> AFAICT the range [de600000, de7ff000] should not be added to the free
> lists.
>
> Can you try with the below patch:
>
> diff --git a/mm/memblock.c b/mm/memblock.c
> index afaefa8fc6ab..7f3c33d53f87 100644
> --- a/mm/memblock.c
> +++ b/mm/memblock.c
> @@ -1994,6 +1994,8 @@ static unsigned long __init __free_memory_core(phys_addr_t start,
>   	unsigned long end_pfn = min_t(unsigned long,
>   				      PFN_DOWN(end), max_low_pfn);
>   
> +	pr_info("%s: range: %pa - %pa, pfn: %lx - %lx\n", __func__, &start, &end, start_pfn, end_pfn);
> +
>   	if (start_pfn >= end_pfn)
>   		return 0;
>   
__free_memory_core, range: 0x80a03000 - 0x80a04000, pfn: 80a03 - 80a04
__free_memory_core, range: 0x80a08000 - 0x80b00000, pfn: 80a08 - 80b00
__free_memory_core, range: 0x812e8058 - 0x83000000, pfn: 812e9 - 83000
__free_memory_core, range: 0x85000000 - 0x85600000, pfn: 85000 - 85600
__free_memory_core, range: 0x86a00000 - 0x87e00000, pfn: 86a00 - 87e00
__free_memory_core, range: 0x8bd00000 - 0x8c500000, pfn: 8bd00 - 8c500
__free_memory_core, range: 0x8e300000 - 0x8ed00000, pfn: 8e300 - 8ed00
__free_memory_core, range: 0x90d00000 - 0xaf2c0000, pfn: 90d00 - af2c0
__free_memory_core, range: 0xaf430000 - 0xaf454000, pfn: af430 - af454
__free_memory_core, range: 0xaf510000 - 0xaf546000, pfn: af510 - af546
__free_memory_core, range: 0xaf560000 - 0xaf580000, pfn: af560 - af580
__free_memory_core, range: 0xafd98000 - 0xafdce000, pfn: afd98 - afdce
__free_memory_core, range: 0xafdd8000 - 0xafe00000, pfn: afdd8 - afe00
__free_memory_core, range: 0xafe18000 - 0xafe80000, pfn: afe18 - afe80
__free_memory_core, range: 0xafee0000 - 0xaff00000, pfn: afee0 - aff00
__free_memory_core, range: 0xaff80000 - 0xaff8d000, pfn: aff80 - aff8d
__free_memory_core, range: 0xafff2000 - 0xafff4580, pfn: afff2 - afff4
__free_memory_core, range: 0xafffe000 - 0xafffe0e0, pfn: afffe - afffe
__free_memory_core, range: 0xafffe4fc - 0xafffe500, pfn: affff - afffe
__free_memory_core, range: 0xafffe6e4 - 0xafffe700, pfn: affff - afffe
__free_memory_core, range: 0xafffe8dc - 0xafffe8e0, pfn: affff - afffe
__free_memory_core, range: 0xafffe970 - 0xafffe980, pfn: affff - afffe
__free_memory_core, range: 0xafffe990 - 0xafffe9a0, pfn: affff - afffe
__free_memory_core, range: 0xafffe9a4 - 0xafffe9c0, pfn: affff - afffe
__free_memory_core, range: 0xafffeb54 - 0xafffeb60, pfn: affff - afffe
__free_memory_core, range: 0xafffecf4 - 0xafffed00, pfn: affff - afffe
__free_memory_core, range: 0xafffefc4 - 0xafffefd8, pfn: affff - afffe
__free_memory_core, range: 0xb0200000 - 0xc0000000, pfn: b0200 - b0200
__free_memory_core, range: 0xcc000000 - 0xdca00000, pfn: cc000 - b0200
__free_memory_core, range: 0xde700000 - 0xdea00000, pfn: de700 - b0200
__free_memory_core, range: 0xe0800000 - 0xe0c00000, pfn: e0800 - b0200
__free_memory_core, range: 0xf4b00000 - 0xf7000000, pfn: f4b00 - b0200
__free_memory_core, range: 0xfda00000 - 0xffffffff, pfn: fda00 - b0200

>   
>>>> [<c023999c>] (get_page_from_freelist) from [<c023a4dc>] (__alloc_pages_nodemask+0x188/0xc08)
>>>> [<c023a4dc>] (__alloc_pages_nodemask) from [<c0223078>] (alloc_zeroed_user_highpage_movable+0x14/0x3c)
>>>> [<c0223078>] (alloc_zeroed_user_highpage_movable) from [<c0226768>] (handle_mm_fault+0x254/0xac8)
>>>> [<c0226768>] (handle_mm_fault) from [<c04ba09c>] (do_page_fault+0x228/0x2f4)
>>>> [<c04ba09c>] (do_page_fault) from [<c0111d80>] (do_DataAbort+0x48/0xd0)
>>>> [<c0111d80>] (do_DataAbort) from [<c0100e00>] (__dabt_usr+0x40/0x60)
>>>>
>>>>           Zone ranges:
>>>>             Normal   [mem 0x0000000080a00000-0x00000000b01fffff]
>>>>             HighMem  [mem 0x00000000b0200000-0x00000000ffffefff]
>>>>           Movable zone start for each node
>>>>           Early memory node ranges
>>>>             node   0: [mem 0x0000000080a00000-0x00000000855fffff]
>>>>             node   0: [mem 0x0000000086a00000-0x0000000087dfffff]
>>>>             node   0: [mem 0x000000008bd00000-0x000000008c4fffff]
>>>>             node   0: [mem 0x000000008e300000-0x000000008ecfffff]
>>>>             node   0: [mem 0x0000000090d00000-0x00000000bfffffff]
>>>>             node   0: [mem 0x00000000cc000000-0x00000000dc9fffff]
>>>>             node   0: [mem 0x00000000de700000-0x00000000de9fffff]
>>>>             node   0: [mem 0x00000000e0800000-0x00000000e0bfffff]
>>>>             node   0: [mem 0x00000000f4b00000-0x00000000f6ffffff]
>>>>             node   0: [mem 0x00000000fda00000-0x00000000ffffefff]
>>>>
>>>>           ----> free_memmap, start_pfn = 85800,  85800000 end_pfn = 86a00, 86a00000
>>>>           ----> free_memmap, start_pfn = 8c800,  8c800000 end_pfn = 8e300, 8e300000
>>>>           ----> free_memmap, start_pfn = 8f000,  8f000000 end_pfn = 90000, 90000000
>>>>           ----> free_memmap, start_pfn = dcc00,  dcc00000 end_pfn = de700, de700000
>>>>           ----> free_memmap, start_pfn = dec00,  dec00000 end_pfn = e0000, e0000000
>>>>           ----> free_memmap, start_pfn = e0c00,  e0c00000 end_pfn = e4000, e4000000
>>>>           ----> free_memmap, start_pfn = f7000,  f7000000 end_pfn = f8000, f8000000
>>>>           === >move_freepages: start_pfn/end_pfn [de601, de7ff], [de600000, de7ff000]
>>>>           :  pfn =de600 pfn2phy = de600000 , page = ef3cc000, page-flags = ffffffff
>>>>           8<--- cut here ---
>>>>           Unable to handle kernel paging request at virtual address fffffffe
>>>>           pgd = 5dd50df5
>>>>           [fffffffe] *pgd=affff861, *pte=00000000, *ppte=00000000
>>>>           Internal error: Oops: 37 [#1] SMP ARM
>>>>           Modules linked in: gmac(O)
>>>>           CPU: 2 PID: 635 Comm: test-oom Tainted: G           O      5.10.0+ #31
>>>>           Hardware name: Hisilicon A9
>>>>           PC is at move_freepages_block+0x150/0x278
>>>>           LR is at move_freepages_block+0x150/0x278
>>>>           pc : [<c02383a4>]    lr : [<c02383a4>]    psr: 200e0393
>>>>           sp : c4179cf8  ip : 00000000  fp : 00000001
>>>>           r10: c4179d58  r9 : 000de7ff  r8 : 00000000
>>>>           r7 : c0863280  r6 : 000de600  r5 : 000de600  r4 : ef3cc000
>>>>           r3 : ffffffff  r2 : 00000000  r1 : ef5d069c  r0 : fffffffe
>>>>           Flags: nzCv  IRQs off  FIQs on  Mode SVC_32  ISA ARM  Segment user
>>>>           Control: 1ac5387d  Table: 83b0c04a  DAC: 55555555
>>>>           Process test-oom (pid: 635, stack limit = 0x25d667df)
>>>>
>>>>