Reverting the patchset "Allocate memmap from hotadded memory (per device)" [1] from today's linux-next fixed a crash while online/offline memory sections. [1] https://lore.kernel.org/linux-mm/20210421102701.25051-1-osalvador@xxxxxxx/ [ 162.327720][ T1694] kernel BUG at include/linux/mm.h:1383! [ 162.333695][ T1694] Internal error: Oops - BUG: 0 [#1] SMP [ 162.339181][ T1694] Modules linked in: loop processor efivarfs ip_tables x_tables ext4 mbcache jbd2 dm_mod igb nvme i2c_algo_bit mlx5_core i2c_core nvme_core firmware_class [ 162.354604][ T1694] CPU: 13 PID: 1694 Comm: ranbug Not tainted 5.12.0-next-20210524+ #4 [ 162.362601][ T1694] Hardware name: MiTAC RAPTOR EV-883832-X3-0001/RAPTOR, BIOS 1.6 06/28/2020 [ 162.371116][ T1694] pstate: 60000005 (nZCv daif -PAN -UAO -TCO BTYPE=--) [ 162.377811][ T1694] pc : memory_subsys_offline+0x1f8/0x250 [ 162.383295][ T1694] lr : memory_subsys_offline+0x1f8/0x250 [ 162.388773][ T1694] sp : ffff80002458f8e0 [ 162.392773][ T1694] x29: ffff80002458f8e0 x28: ffff800010914d30 x27: 0000000000000000 [ 162.400602][ T1694] x26: 0000000000002000 x25: 1fffe00002550401 x24: ffff000012a82008 [ 162.408431][ T1694] x23: fffffc0000000000 x22: 0000000000008000 x21: 0000000000000001 [ 162.416259][ T1694] x20: ffffffffffffffff x19: ffff000012a82018 x18: ffff0008527b6a70 [ 162.424086][ T1694] x17: 0000000000000000 x16: 0000000000000007 x15: 00000000000000c8 [ 162.431914][ T1694] x14: 0000000000000000 x13: ffff800011c6eea4 x12: ffff60136ceb8574 [ 162.439742][ T1694] x11: 1fffe0136ceb8573 x10: ffff60136ceb8573 x9 : dfff800000000000 [ 162.447570][ T1694] x8 : ffff009b675c2b9b x7 : 0000000000000001 x6 : ffff009b675c2b98 [ 162.455398][ T1694] x5 : 00009fec93147a8d x4 : ffff009b675c2b98 x3 : 1fffe0010a4f6c09 [ 162.463226][ T1694] x2 : 0000000000000000 x1 : 0000000000000000 x0 : 0000000000000034 [ 162.471054][ T1694] Call trace: [ 162.474186][ T1694] memory_subsys_offline+0x1f8/0x250 [ 162.479318][ T1694] device_offline+0x154/0x1d8 [ 162.483844][ T1694] online_store+0xa4/0x118 [ 162.488107][ T1694] dev_attr_store+0x44/0x78 [ 162.492457][ T1694] sysfs_kf_write+0xe8/0x138 [ 162.496896][ T1694] kernfs_fop_write_iter+0x26c/0x3d0 [ 162.502028][ T1694] new_sync_write+0x2bc/0x4f8 [ 162.506552][ T1694] vfs_write+0x718/0xc88 [ 162.510643][ T1694] ksys_write+0xf8/0x1e0 [ 162.514732][ T1694] __arm64_sys_write+0x74/0xa8 [ 162.519342][ T1694] invoke_syscall.constprop.0+0x78/0x1e8 [ 162.524824][ T1694] do_el0_svc+0xe4/0x298 [ 162.528914][ T1694] el0_svc+0x20/0x30 [ 162.532658][ T1694] el0_sync_handler+0xb0/0xb8 [ 162.537181][ T1694] el0_sync+0x178/0x180 [ 162.541187][ T1694] Code: f00033e1 91318021 91090021 97e38d8b (d4210000) [ 162.547968][ T1694] ---[ end trace 2a1964462a219f20 ]--- [ 162.553273][ T1694] Kernel panic - not syncing: Oops - BUG: Fatal exception [ 162.560250][ T1694] SMP: stopping secondary CPUs [ 162.564871][ T1694] Kernel Offset: disabled [ 162.569045][ T1694] CPU features: 0x00000251,20000846 [ 162.574089][ T1694] Memory Limit: none [ 162.577849][ T1694] ---[ end Kernel panic - not syncing: Oops - BUG: Fatal exception ]--- Occasionally, it failed like this, [ 119.319732][ T1387] Unable to handle kernel paging request at virtual address dfff800000000000 [ 119.328575][ T1387] Mem abort info: [ 119.332073][ T1387] ESR = 0x96000004 [ 119.335879][ T1387] EC = 0x25: DABT (current EL), IL = 32 bits [ 119.341895][ T1387] SET = 0, FnV = 0 [ 119.345697][ T1387] EA = 0, S1PTW = 0 [ 119.349542][ T1387] Data abort info: [ 119.353121][ T1387] ISV = 0, ISS = 0x00000004 [ 119.358387][ T1387] CM = 0, WnR = 0 [ 119.362055][ T1387] [dfff800000000000] address between user and kernel address ranges [ 119.370166][ T1387] Internal error: Oops: 96000004 [#1] SMP [ 119.375739][ T1387] Modules linked in: loop processor efivarfs ip_tables x_tables ext4 mbcache jbd2 dm_mod igb i2c_algo_bit nvme mlx5_core i2c_core nvme_core firmware_class [ 119.391164][ T1387] CPU: 2 PID: 1387 Comm: ranbug Not tainted 5.13.0-rc3+ #16 [ 119.398294][ T1387] Hardware name: MiTAC RAPTOR EV-883832-X3-0001/RAPTOR, BIOS 1.6 06/28/2020 [ 119.406810][ T1387] pstate: 20000005 (nzCv daif -PAN -UAO -TCO BTYPE=--) [ 119.413504][ T1387] pc : hex_dump_to_buffer+0x3ac/0x9f0 [ 119.418728][ T1387] lr : print_hex_dump+0x10c/0x1d8 [ 119.423600][ T1387] sp : ffff800021b4f3a0 [ 119.427600][ T1387] x29: ffff800021b4f3a0 x28: dfff800000000000 x27: ffff800021b4f500 [ 119.435429][ T1387] x26: 0000000000000083 x25: fffffffffffffffe x24: 0000000000000008 [ 119.443257][ T1387] x23: 0000000000000045 x22: 0000000000000083 x21: 0000000000000020 [ 119.451084][ T1387] x20: 0000000000000000 x19: ffff800021b4f500 x18: ffff0008650187e8 [ 119.458912][ T1387] x17: 0000000000000000 x16: 0000000000000007 x15: 00000000000000c8 [ 119.466740][ T1387] x14: 0000000000000000 x13: ffff800011c6eea4 x12: 000000000000f1f1 [ 119.474568][ T1387] x11: 0000000000000005 x10: ffff8000112eec80 x9 : 00000000f3f3f3f3 [ 119.482396][ T1387] x8 : 0000000000000010 x7 : 0000000000000000 x6 : fffffffffffffffe [ 119.490224][ T1387] x5 : 0000000000000083 x4 : 0000000000000000 x3 : 1fffffffffffffff [ 119.498051][ T1387] x2 : ffff8000112eecc0 x1 : 0000000000000006 x0 : 0000000000000000 [ 119.505879][ T1387] Call trace: [ 119.509011][ T1387] hex_dump_to_buffer+0x3ac/0x9f0 [ 119.513884][ T1387] print_hex_dump+0x10c/0x1d8 [ 119.518407][ T1387] __dump_page+0x8c8/0xba8 [ 119.522672][ T1387] dump_page+0x20/0x50 [ 119.526587][ T1387] memory_subsys_offline+0x1f8/0x250 [ 119.531722][ T1387] device_offline+0x154/0x1d8 [ 119.536247][ T1387] online_store+0xa4/0x118 [ 119.540511][ T1387] dev_attr_store+0x44/0x78 [ 119.544860][ T1387] sysfs_kf_write+0xe8/0x138 [ 119.549298][ T1387] kernfs_fop_write_iter+0x26c/0x3d0 [ 119.554429][ T1387] new_sync_write+0x2bc/0x4f8 [ 119.558953][ T1387] vfs_write+0x718/0xc88 [ 119.563042][ T1387] ksys_write+0xf8/0x1e0 [ 119.567130][ T1387] __arm64_sys_write+0x74/0xa8 [ 119.571740][ T1387] invoke_syscall.constprop.0+0x78/0x1e8 [ 119.577222][ T1387] do_el0_svc+0xe4/0x298 [ 119.581311][ T1387] el0_svc+0x20/0x30 [ 119.585054][ T1387] el0_sync_handler+0xb0/0xb8 [ 119.589578][ T1387] el0_sync+0x178/0x180 [ 119.593583][ T1387] Code: 1200080b 120008c1 d343fc00 38fc6864 (38fc6803) [ 119.600364][ T1387] ---[ end trace b03c958bc1accb66 ]--- [ 119.605669][ T1387] Kernel panic - not syncing: Oops: Fatal exception [ 119.612124][ T1387] SMP: stopping secondary CPUs [ 119.616747][ T1387] Kernel Offset: disabled [ 119.620923][ T1387] CPU features: 0x00000251,20000846 [ 119.625968][ T1387] Memory Limit: none [ 119.629728][ T1387] ---[ end Kernel panic - not syncing: Oops: Fatal exception ]---