Re: [PATCH v1] mm: relax deferred struct page requirements

[Pasha Tatashin <Pavel.Tatashin@microsoft.com>]

Thanks Jiri, I am now able to reproduce it with your new config.

I have tried yesterday to enable sparsemem and deferred_struct_init on
x86_32, and that kernel booted fine, there must be something else in
your config that helps to trigger this problem. I am studying it now.

[    0.051245] Initializing CPU#0
[    0.051682] Initializing HighMem for node 0 (000367fe:0007ffe0)
[    0.067499] BUG: unable to handle kernel NULL pointer dereference at
00000028
[    0.068452] *pdpt = 0000000000000000 *pde = f000ff53f000ff53
[    0.069105] Oops: 0000 [#1] PREEMPT SMP PTI
[    0.069595] CPU: 0 PID: 0 Comm: swapper Not tainted
4.19.0-rc1-pae_pt_jiri #1
[    0.070382] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS 1.11.0-20171110_100015-anatol 04/01/2014
[    0.071545] EIP: free_unref_page_prepare.part.70+0x2c/0x50
[    0.072178] Code: 19 e9 ff 89 d1 55 c1 ea 11 c1 e9 07 8b 14 d5 44 52
fd d6 81 e1 fc 03 00 00 89 e5 56 53 89 cb be 1d 00 00 00 c1 eb 05 83 e1
1f <8b> 14 9a 29 ce 89 f1 d3 ea 83 e2 07 89 50 10 b8 01 00 00 00 5b 5e
[    0.074296] EAX: f4cfa000 EBX: 0000000a ECX: 00000010 EDX: 00000000
[    0.075005] ESI: 0000001d EDI: 0007ffe0 EBP: d6d41ed0 ESP: d6d41ec8
[    0.075714] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 EFLAGS: 00210002
[    0.076508] CR0: 80050033 CR2: 00000028 CR3: 16f20000 CR4: 000406b0
[    0.077242] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000
[    0.077934] DR6: fffe0ff0 DR7: 00000400
[    0.078380] Call Trace:
[    0.078670]  free_unref_page+0x3a/0x90
[    0.079136]  __free_pages+0x25/0x30
[    0.079533]  free_highmem_page+0x1e/0x50
[    0.079978]  add_highpages_with_active_regions+0xd1/0x11f
[    0.080592]  set_highmem_pages_init+0x67/0x7d
[    0.081076]  mem_init+0x30/0x1fc
[    0.081434]  start_kernel+0x1cc/0x44c
[    0.081874]  i386_start_kernel+0x98/0x9c
[    0.082401]  startup_32_smp+0x164/0x168
[    0.082873] Modules linked in:
[    0.083228] CR2: 0000000000000028
[    0.083606] ---[ end trace a5990d9ace2ec990 ]---
[    0.084128] EIP: free_unref_page_prepare.part.70+0x2c/0x50
[    0.084747] Code: 19 e9 ff 89 d1 55 c1 ea 11 c1 e9 07 8b 14 d5 44 52
fd d6 81 e1 fc 03 00 00 89 e5 56 53 89 cb be 1d 00 00 00 c1 eb 05 83 e1
1f <8b> 14 9a 29 ce 89 f1 d3 ea 83 e2 07 89 50 10 b8 01 00 00 00 5b 5e
[    0.086874] EAX: f4cfa000 EBX: 0000000a ECX: 00000010 EDX: 00000000
[    0.087581] ESI: 0000001d EDI: 0007ffe0 EBP: d6d41ed0 ESP: d6f27efc
[    0.088287] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 EFLAGS: 00210002
[    0.089139] CR0: 80050033 CR2: 00000028 CR3: 16f20000 CR4: 000406b0
[    0.089850] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000
[    0.090557] DR6: fffe0ff0 DR7: 00000400
[    0.090992] Kernel panic - not syncing: Attempted to kill the idle task!


Pavel

On 8/31/18 7:29 AM, Jiri Slaby wrote:
> On 08/31/2018, 01:26 PM, Jiri Slaby wrote:
>> On 08/30/2018, 05:45 PM, Pasha Tatashin wrote:
>>> Hi Jiri,
>>>
>>> I believe this bug is fixed with this change:
>>>
>>> d39f8fb4b7776dcb09ec3bf7a321547083078ee3
>>> mm: make DEFERRED_STRUCT_PAGE_INIT explicitly depend on SPARSEMEM
>>
>> Hi,
>>
>> it only shifted. Enabling only SPARSEMEM works fine, enabling also
>> DEFERRED_STRUCT_PAGE_INIT doesn't even boot – immediately reboots
>> (config attached).
> 
> Wow, earlyprintk is up at the moment of crash already:
> [    0.000000] Linux version 4.19.0-rc1-pae (jslaby@kunlun) (gcc version
> 4.8.5 (SUSE Linux)) #4 SMP PREEMPT Fri Aug 31 13:18:33 CEST 2018
> [    0.000000] x86/fpu: x87 FPU will use FXSAVE
> [    0.000000] BIOS-provided physical RAM map:
> [    0.000000] BIOS-e820: [mem 0x0000000000000000-0x000000000009fbff] usable
> [    0.000000] BIOS-e820: [mem 0x000000000009fc00-0x000000000009ffff]
> reserved
> [    0.000000] BIOS-e820: [mem 0x00000000000f0000-0x00000000000fffff]
> reserved
> [    0.000000] BIOS-e820: [mem 0x0000000000100000-0x000000007cfdffff] usable
> [    0.000000] BIOS-e820: [mem 0x000000007cfe0000-0x000000007cffffff]
> reserved
> [    0.000000] BIOS-e820: [mem 0x00000000feffc000-0x00000000feffffff]
> reserved
> [    0.000000] BIOS-e820: [mem 0x00000000fffc0000-0x00000000ffffffff]
> reserved
> [    0.000000] bootconsole [earlyser0] enabled
> [    0.000000] NX (Execute Disable) protection: active
> [    0.000000] SMBIOS 2.8 present.
> [    0.000000] DMI: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
> 1.0.0-prebuilt.qemu-project.org 04/01/2014
> [    0.000000] Hypervisor detected: KVM
> [    0.000000] kvm-clock: Using msrs 4b564d01 and 4b564d00
> [    0.000002] kvm-clock: cpu 0, msr 1d12c001, primary cpu clock
> [    0.000002] kvm-clock: using sched offset of 1597117996 cycles
> [    0.001395] clocksource: kvm-clock: mask: 0xffffffffffffffff
> max_cycles: 0x1cd42e4dffb, max_idle_ns: 881590591483 ns
> [    0.006245] tsc: Detected 2808.000 MHz processor
> [    0.010055] last_pfn = 0x7cfe0 max_arch_pfn = 0x1000000
> [    0.011483] x86/PAT: PAT not supported by CPU.
> [    0.012580] x86/PAT: Configuration [0-7]: WB  WT  UC- UC  WB  WT  UC-
> UC
> [    0.020644] found SMP MP-table at [mem 0x000f5d20-0x000f5d2f] mapped
> at [(ptrval)]
> [    0.023528] Scanning 1 areas for low memory corruption
> [    0.025047] ACPI: Early table checksum verification disabled
> [    0.026581] ACPI: RSDP 0x00000000000F5B40 000014 (v00 BOCHS )
> [    0.028031] ACPI: RSDT 0x000000007CFE157C 000030 (v01 BOCHS  BXPCRSDT
> 00000001 BXPC 00000001)
> [    0.029996] ACPI: FACP 0x000000007CFE1458 000074 (v01 BOCHS  BXPCFACP
> 00000001 BXPC 00000001)
> [    0.032234] ACPI: DSDT 0x000000007CFE0040 001418 (v01 BOCHS  BXPCDSDT
> 00000001 BXPC 00000001)
> [    0.034662] ACPI: FACS 0x000000007CFE0000 000040
> [    0.036126] ACPI: APIC 0x000000007CFE14CC 000078 (v01 BOCHS  BXPCAPIC
> 00000001 BXPC 00000001)
> [    0.038235] ACPI: HPET 0x000000007CFE1544 000038 (v01 BOCHS  BXPCHPET
> 00000001 BXPC 00000001)
> [    0.040373] No NUMA configuration found
> [    0.041407] Faking a node at [mem 0x0000000000000000-0x000000007cfdffff]
> [    0.043306] NODE_DATA(0) allocated [mem 0x367fc000-0x367fcfff]
> [    0.044958] 1127MB HIGHMEM available.
> [    0.045940] 871MB LOWMEM available.
> [    0.046978]   mapped low ram: 0 - 367fe000
> [    0.048200]   low ram: 0 - 367fe000
> [    0.050830] Zone ranges:
> [    0.051625]   DMA      [mem 0x0000000000001000-0x0000000000ffffff]
> [    0.053295]   Normal   [mem 0x0000000001000000-0x00000000367fdfff]
> [    0.054921]   HighMem  [mem 0x00000000367fe000-0x000000007cfdffff]
> [    0.056408] Movable zone start for each node
> [    0.057452] Early memory node ranges
> [    0.058377]   node   0: [mem 0x0000000000001000-0x000000000009efff]
> [    0.059946]   node   0: [mem 0x0000000000100000-0x000000007cfdffff]
> [    0.061825] Reserved but unavailable: 12418 pages
> [    0.061828] Initmem setup node 0 [mem
> 0x0000000000001000-0x000000007cfdffff]
> [    0.074252] Using APIC driver default
> [    0.075615] ACPI: PM-Timer IO Port: 0x608
> [    0.076574] ACPI: LAPIC_NMI (acpi_id[0xff] dfl dfl lint[0x1])
> [    0.077995] IOAPIC[0]: apic_id 0, version 17, address 0xfec00000, GSI
> 0-23
> [    0.079610] ACPI: INT_SRC_OVR (bus 0 bus_irq 0 global_irq 2 dfl dfl)
> [    0.081111] ACPI: INT_SRC_OVR (bus 0 bus_irq 5 global_irq 5 high level)
> [    0.082786] ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 9 high level)
> [    0.084297] ACPI: INT_SRC_OVR (bus 0 bus_irq 10 global_irq 10 high level)
> [    0.085933] ACPI: INT_SRC_OVR (bus 0 bus_irq 11 global_irq 11 high level)
> [    0.087729] Using ACPI (MADT) for SMP configuration information
> [    0.089119] ACPI: HPET id: 0x8086a201 base: 0xfed00000
> [    0.090351] smpboot: Allowing 1 CPUs, 0 hotplug CPUs
> [    0.091561] PM: Registered nosave memory: [mem 0x00000000-0x00000fff]
> [    0.093361] PM: Registered nosave memory: [mem 0x0009f000-0x0009ffff]
> [    0.096382] PM: Registered nosave memory: [mem 0x000a0000-0x000effff]
> [    0.098130] PM: Registered nosave memory: [mem 0x000f0000-0x000fffff]
> [    0.099729] [mem 0x7d000000-0xfeffbfff] available for PCI devices
> [    0.101034] Booting paravirtualized kernel on KVM
> [    0.102034] clocksource: refined-jiffies: mask: 0xffffffff
> max_cycles: 0xffffffff, max_idle_ns: 7645519600211568 ns
> [    0.104207] random: get_random_bytes called from
> start_kernel+0x77/0x47c with crng_init=0
> [    0.105913] setup_percpu: NR_CPUS:64 nr_cpumask_bits:64 nr_cpu_ids:1
> nr_node_ids:1
> [    0.107548] percpu: Embedded 31 pages/cpu @(ptrval) s94604 r0 d32372
> u126976
> [    0.109019] KVM setup async PF for cpu 0
> [    0.109825] kvm-stealtime: cpu 0, msr 367e5300
> [    0.110755] Built 1 zonelists, mobility grouping on.  Total pages: 509908
> [    0.112113] Policy zone: HighMem
> [    0.112755] Kernel command line: earlyprintk=serial
> [    0.113773] Dentry cache hash table entries: 131072 (order: 7, 524288
> bytes)
> [    0.115788] Inode-cache hash table entries: 65536 (order: 6, 262144
> bytes)
> [    0.117465] Initializing CPU#0
> [    0.118522] Initializing HighMem for node 0 (000367fe:0007cfe0)
> [    0.161140] BUG: unable to handle kernel NULL pointer dereference at
> 00000028
> [    0.162671] *pdpt = 0000000000000000 *pde = f000ff53f000ff53
> [    0.163857] Oops: 0000 [#1] PREEMPT SMP PTI
> [    0.164862] CPU: 0 PID: 0 Comm: swapper Not tainted 4.19.0-rc1-pae #4
> openSUSE Tumbleweed (unreleased)
> [    0.167041] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
> BIOS 1.0.0-prebuilt.qemu-project.org 04/01/2014
> [    0.169389] EIP: free_unref_page_prepare.part.75+0x26/0x50
> [    0.170337] Code: 00 00 00 00 e8 e7 a4 e9 ff 89 d1 c1 ea 11 55 8b 14
> d5 84 d2 1c dd c1 e9 07 89 e5 56 81 e1 fc 03 00 00 53 89 cb c1 eb 05 89
> ce <8b> 14 9a 83 e6 1f b9 1d 00 00 00 29 f1 d3 ea 83 e2 07 89 50 10 b8
> [    0.174205] EAX: f4cfa000 EBX: 0000000a ECX: 00000150 EDX: 00000000
> [    0.175422] ESI: 00000150 EDI: 00d80000 EBP: dcf2be50 ESP: dcf2be48
> [    0.176724] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 EFLAGS: 00210007
> [    0.178075] CR0: 80050033 CR2: 00000028 CR3: 1d118000 CR4: 000006b0
> [    0.179354] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000
> [    0.180629] DR6: fffe0ff0 DR7: 00000400
> [    0.181400] Call Trace:
> [    0.181907]  free_unref_page+0x3a/0x90
> [    0.182642]  __free_pages+0x25/0x30
> [    0.183748]  free_highmem_page+0x1e/0x50
> [    0.184594]  add_highpages_with_active_regions+0x123/0x125
> [    0.185813]  set_highmem_pages_init+0x83/0x8d
> [    0.186847]  mem_init+0x26/0x240
> [    0.187590]  ? vprintk_func+0x38/0xd0
> [    0.188427]  ? idt_setup_from_table.constprop.1+0x45/0x70
> [    0.189666]  ? set_intr_gate+0x39/0x40
> [    0.190551]  ? general_protection+0xc/0xc
> [    0.191818]  ? update_intr_gate+0x1e/0x20
> [    0.192817]  ? kvm_apf_trap_init+0x17/0x19
> [    0.193800]  ? trap_init+0x77/0x7d
> [    0.194644]  start_kernel+0x203/0x47c
> [    0.195491]  ? set_init_arg+0x57/0x57
> [    0.196385]  i386_start_kernel+0x143/0x146
> [    0.197351]  startup_32_smp+0x164/0x168
> [    0.198232] Modules linked in:
> [    0.199072] CR2: 0000000000000028
> [    0.199983] ---[ end trace 69f4a864c8bd9bcd ]---
> [    0.201198] EIP: free_unref_page_prepare.part.75+0x26/0x50
> [    0.202610] Code: 00 00 00 00 e8 e7 a4 e9 ff 89 d1 c1 ea 11 55 8b 14
> d5 84 d2 1c dd c1 e9 07 89 e5 56 81 e1 fc 03 00 00 53 89 cb c1 eb 05 89
> ce <8b> 14 9a 83 e6 1f b9 1d 00 00 00 29 f1 d3 ea 83 e2 07 89 50 10 b8
> [    0.206942] EAX: f4cfa000 EBX: 0000000a ECX: 00000150 EDX: 00000000
> [    0.208177] ESI: 00000150 EDI: 00d80000 EBP: dcf2be50 ESP: dd11fefc
> [    0.209438] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 EFLAGS: 00210007
> [    0.210826] CR0: 80050033 CR2: 00000028 CR3: 1d118000 CR4: 000006b0
> [    0.212155] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000
> [    0.213752] DR6: fffe0ff0 DR7: 00000400
> 
> 
>>
>> thanks,
>>
> 
>