On Fri, Aug 23, 2024 at 10:43:11AM GMT, Bert Karwatzki wrote: [snip] > > @@ -731,21 +708,31 @@ static void vms_complete_munmap_vmas(struct vma_munmap_struct *vms, > > if (vms->unlock) > > mmap_write_downgrade(mm); > > > > - prev = vma_iter_prev_range(vms->vmi); > > - next = vma_next(vms->vmi); > > - if (next) > > - vma_iter_prev_range(vms->vmi); > > - > > /* > > * We can free page tables without write-locking mmap_lock because VMAs > > * were isolated before we downgraded mmap_lock. > > */ > > mas_set(mas_detach, 1); > > - unmap_region(mm, mas_detach, vms->vma, prev, next, vms->start, vms->end, > > - vms->vma_count, !vms->unlock); > > - /* Statistics and freeing VMAs */ > > + unmap_region(mm, mas_detach, vms->vma, vms->prev, vms->next, > > + vms->start, vms->end, vms->vma_count, !vms->unlock); > > + /* Update high watermark before we lower total_vm */ > > + update_hiwater_vm(mm); > > + /* Stat accounting */ > > + WRITE_ONCE(mm->total_vm, READ_ONCE(mm->total_vm) - vms->nr_pages); > > + mm->exec_vm -= vms->exec_vm; > > + mm->stack_vm -= vms->stack_vm; > > + mm->data_vm -= vms->data_vm; > > + /* Paranoid bookkeeping */ > > + VM_WARN_ON(vms->exec_vm > mm->exec_vm); > > + VM_WARN_ON(vms->stack_vm > mm->stack_vm); > > + VM_WARN_ON(vms->data_vm > mm->data_vm); Hang on... I didn't read this closely enough (clearly!) we're doing these checks _after_ we decrement the counters, which is... not correct :) Your processes must be reducing their data_vm value to something less than what was reduced during the munmap operation. Liam - I suggest we put these checks before we decrement. > > + > > I'm running the v7 Patchset on linux-next-20240822 and I get lots of these > errors (right on boot) (both when using the complete patchset and when using > only the patches up to this): > > [ T620] WARNING: CPU: 6 PID: 620 at mm/vma.c:725 > vms_complete_munmap_vmas+0x1d8/0x200 > [ T620] Modules linked in: amd_atl ecc mc sparse_keymap wmi_bmof edac_mce_amd > snd snd_pci_acp3x k10temp soundcore ccp battery ac button hid_sensor_gyro_3d > hid_sensor_als hid_sensor_magn_3d hid_sensor_prox hid_sensor_accel_3d > hid_sensor_trigger industrialio_triggered_buffer kfifo_buf industrialio amd_pmc > hid_sensor_iio_common joydev evdev serio_raw mt7921e mt7921_common mt792x_lib > mt76_connac_lib mt76 mac80211 libarc4 cfg80211 rfkill msr nvme_fabrics fuse > efi_pstore configfs efivarfs autofs4 ext4 crc32c_generic mbcache jbd2 usbhid > amdgpu i2c_algo_bit drm_ttm_helper ttm drm_exec drm_suballoc_helper amdxcp > xhci_pci drm_buddy hid_sensor_hub xhci_hcd nvme mfd_core gpu_sched > hid_multitouch hid_generic crc32c_intel psmouse usbcore i2c_piix4 > drm_display_helper amd_sfh i2c_hid_acpi i2c_smbus usb_common crc16 nvme_core > r8169 i2c_hid hid i2c_designware_platform i2c_designware_core > [ T620] CPU: 6 UID: 0 PID: 620 Comm: fsck.vfat Not tainted 6.11.0-rc4-next- > 20240822-liamh-v7-00021-gc6686c81601f #322 > [ T620] Hardware name: Micro-Star International Co., Ltd. Alpha 15 B5EEK/MS- > 158L, BIOS E158LAMS.107 11/10/2021 > [ T620] RIP: 0010:vms_complete_munmap_vmas+0x1d8/0x200 > [ T620] Code: 8b 85 a8 00 00 00 a8 01 74 35 8b 85 e0 00 00 00 48 8d bd a8 00 00 > 00 83 c0 01 89 85 e0 00 00 00 e8 7d 39 e8 ff e9 63 fe ff ff <0f> 0b e9 eb fe ff > ff 0f 0b e9 d0 fe ff ff 0f 0b e9 d3 fe ff ff 0f > [ T620] RSP: 0018:ffffa415c09d7d10 EFLAGS: 00010283 > [ T620] RAX: 00000000000000cd RBX: ffffa415c09d7d90 RCX: 000000000000018e > [ T620] RDX: 0000000000000021 RSI: 00000000000019d9 RDI: ffff9073ee7a6400 > [ T620] RBP: ffff906541341f80 R08: 0000000000000000 R09: 000000000000080a > [ T620] R10: 000000000001d4de R11: 0000000000000140 R12: ffffa415c09d7d48 > [ T620] R13: 00007fbd5ea5f000 R14: 00007fbd5eb5efff R15: ffffa415c09d7d90 > [ T620] FS: 00007fbd5ec38740(0000) GS:ffff9073ee780000(0000) > knlGS:0000000000000000 > [ T620] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > [ T620] CR2: 00007fc336339c90 CR3: 000000010a39e000 CR4: 0000000000750ef0 > [ T620] PKRU: 55555554 > [ T620] Call Trace: > [ T620] <TASK> > [ T620] ? __warn.cold+0x90/0x9e > [ T620] ? vms_complete_munmap_vmas+0x1d8/0x200 > [ T620] ? report_bug+0xfa/0x140 > [ T620] ? handle_bug+0x53/0x90 > [ T620] ? exc_invalid_op+0x17/0x70 > [ T620] ? asm_exc_invalid_op+0x1a/0x20 > [ T620] ? vms_complete_munmap_vmas+0x1d8/0x200 > [ T620] do_vmi_align_munmap+0x1e0/0x260 > [ T620] do_vmi_munmap+0xbe/0x160 > [ T620] __vm_munmap+0x96/0x110 > [ T620] __x64_sys_munmap+0x16/0x20 > [ T620] do_syscall_64+0x5f/0x170 > [ T620] entry_SYSCALL_64_after_hwframe+0x55/0x5d > [ T620] RIP: 0033:0x7fbd5ed3ec57 > [ T620] Code: 73 01 c3 48 8b 0d c1 71 0d 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e > 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 0b 00 00 00 0f 05 <48> 3d 01 f0 ff ff > 73 01 c3 48 8b 0d 91 71 0d 00 f7 d8 64 89 01 48 > [ T620] RSP: 002b:00007fff0b04d298 EFLAGS: 00000202 ORIG_RAX: 000000000000000b > [ T620] RAX: ffffffffffffffda RBX: ffffffffffffff88 RCX: 00007fbd5ed3ec57 > [ T620] RDX: 0000000000000000 RSI: 0000000000100000 RDI: 00007fbd5ea5f000 > [ T620] RBP: 0000000000000002 R08: 0000000000100000 R09: 0000000000000007 > [ T620] R10: 0000000000000007 R11: 0000000000000202 R12: 00007fff0b04d588 > [ T620] R13: 000055b76c789fc6 R14: 00007fff0b04d360 R15: 00007fff0b04d3c0 > [ T620] </TASK> > [ T620] ---[ end trace 0000000000000000 ]--- > > > Bert Karwatzki
