On 2018/09/10 21:55, Michal Hocko wrote:
> This is a very coarse implementation of the idea I've had before.
> Please note that I haven't tested it yet. It is mostly to show the
> direction I would wish to go for.
Hmm, this patchset does not allow me to boot. ;-)
free_pgd_range(&tlb, vma->vm_start, vma->vm_prev->vm_end,
FIRST_USER_ADDRESS, USER_PGTABLES_CEILING);
[ 1.875675] sched_clock: Marking stable (1810466565, 65169393)->(1977240380, -101604422)
[ 1.877833] registered taskstats version 1
[ 1.877853] Loading compiled-in X.509 certificates
[ 1.878835] zswap: loaded using pool lzo/zbud
[ 1.880835] BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
[ 1.881792] PGD 0 P4D 0
[ 1.881812] Oops: 0000 [#1] SMP DEBUG_PAGEALLOC
[ 1.882792] CPU: 1 PID: 121 Comm: modprobe Not tainted 4.19.0-rc3+ #469
[ 1.883803] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 05/19/2017
[ 1.884792] RIP: 0010:exit_mmap+0x122/0x1f0
[ 1.884812] Code: 8b 5b 10 48 85 db 75 e7 45 84 e4 48 8b 45 00 0f 85 9a 00 00 00 48 8b 50 18 48 8b 30 48 8d 7c 24 08 45 31 c0 31 c9 48 89 04 24 <48> 8b 52 08 e8 45 3b ff ff 48 8d 7c 24 08 31 f6 48 c7 c2 ff ff ff
[ 1.886793] RSP: 0018:ffffc90000897de0 EFLAGS: 00010246
[ 1.887812] RAX: ffff88013494fcc0 RBX: 0000000000000000 RCX: 0000000000000000
[ 1.888872] RDX: 0000000000000000 RSI: 0000000000400000 RDI: ffffc90000897de8
[ 1.889794] RBP: ffff880134950040 R08: 0000000000000000 R09: 0000000000000000
[ 1.890792] R10: 0000000000000001 R11: 0000000000081741 R12: 0000000000000000
[ 1.891794] R13: ffff8801348fe240 R14: ffff8801348fe928 R15: 0000000000000000
[ 1.892836] FS: 0000000000000000(0000) GS:ffff88013b240000(0000) knlGS:0000000000000000
[ 1.893792] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1.894792] CR2: 0000000000000008 CR3: 000000000220f001 CR4: 00000000001606e0
[ 1.895797] Call Trace:
[ 1.895817] ? switch_mm_irqs_off+0x2e1/0x870
[ 1.895837] mmput+0x63/0x130
[ 1.895857] do_exit+0x2a7/0xc80
[ 1.895877] ? __do_page_fault+0x219/0x520
[ 1.896793] ? trace_hardirqs_on_thunk+0x1a/0x1c
[ 1.896813] do_group_exit+0x41/0xc0
[ 1.896833] __x64_sys_exit_group+0xf/0x10
[ 1.896853] do_syscall_64+0x4f/0x1f0
[ 1.896873] entry_SYSCALL_64_after_hwframe+0x49/0xbe
[ 1.896893] RIP: 0033:0x7fa50e122909
[ 1.896913] Code: Bad RIP value.
[ 1.896933] RSP: 002b:00007fff0fdb96a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
[ 1.897792] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007fa50e122909
[ 1.898792] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000001
[ 1.899795] RBP: 00007fa50e41f838 R08: 000000000000003c R09: 00000000000000e7
[ 1.900800] R10: ffffffffffffff70 R11: 0000000000000246 R12: 00007fa50e41f838
[ 1.901793] R13: 00007fa50e424e80 R14: 0000000000000000 R15: 0000000000000000
[ 1.902796] Modules linked in:
[ 1.902816] CR2: 0000000000000008
[ 1.902836] ---[ end trace a1a4ea7953190d43 ]---
[ 1.902856] RIP: 0010:exit_mmap+0x122/0x1f0
[ 1.902876] Code: 8b 5b 10 48 85 db 75 e7 45 84 e4 48 8b 45 00 0f 85 9a 00 00 00 48 8b 50 18 48 8b 30 48 8d 7c 24 08 45 31 c0 31 c9 48 89 04 24 <48> 8b 52 08 e8 45 3b ff ff 48 8d 7c 24 08 31 f6 48 c7 c2 ff ff ff
[ 1.905792] RSP: 0018:ffffc90000897de0 EFLAGS: 00010246
[ 1.906792] RAX: ffff88013494fcc0 RBX: 0000000000000000 RCX: 0000000000000000
[ 1.907799] RDX: 0000000000000000 RSI: 0000000000400000 RDI: ffffc90000897de8
[ 1.908837] RBP: ffff880134950040 R08: 0000000000000000 R09: 0000000000000000
[ 1.909814] R10: 0000000000000001 R11: 0000000000081741 R12: 0000000000000000
[ 1.910812] R13: ffff8801348fe240 R14: ffff8801348fe928 R15: 0000000000000000
[ 1.911807] FS: 0000000000000000(0000) GS:ffff88013b240000(0000) knlGS:0000000000000000
[ 1.912792] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1.913820] CR2: 00007fa50e1228df CR3: 000000000220f001 CR4: 00000000001606e0
[ 1.914812] Fixing recursive fault but reboot is needed!
[ 2.076860] input: ImPS/2 Generic Wheel Mouse as /devices/platform/i8042/serio1/input/input3
[ 2.667963] tsc: Refined TSC clocksource calibration: 2793.558 MHz
