Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Change status variable name in code to be consistent in the files #8

Open
dotan-barak opened this issue Nov 8, 2021 · 0 comments
Open

Comments

@dotan-barak
Copy link
Collaborator

In some files, there is a use to the variable 'ret' and in others the variable 'err' is used.
I would suggest to be consistent and use 'ret' everywhere.

longlimsft pushed a commit that referenced this issue Nov 18, 2021
The inode switching code is not suited for dax inodes.  An attempt to
switch a dax inode to a parent writeback structure (as a part of a
writeback cleanup procedure) results in a panic like this:

  run fstests generic/270 at 2021-07-15 05:54:02
  XFS (pmem0p2): EXPERIMENTAL big timestamp feature in use.  Use at your own risk!
  XFS (pmem0p2): DAX enabled. Warning: EXPERIMENTAL, use at your own risk
  XFS (pmem0p2): EXPERIMENTAL inode btree counters feature in use. Use at your own risk!
  XFS (pmem0p2): Mounting V5 Filesystem
  XFS (pmem0p2): Ending clean mount
  XFS (pmem0p2): Quotacheck needed: Please wait.
  XFS (pmem0p2): Quotacheck: Done.
  XFS (pmem0p2): xlog_verify_grant_tail: space > BBTOB(tail_blocks)
  XFS (pmem0p2): xlog_verify_grant_tail: space > BBTOB(tail_blocks)
  XFS (pmem0p2): xlog_verify_grant_tail: space > BBTOB(tail_blocks)
  BUG: unable to handle page fault for address: 0000000005b0f669
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD 0 P4D 0
  Oops: 0000 [#1] SMP PTI
  CPU: 13 PID: 10479 Comm: kworker/13:16 Not tainted 5.14.0-rc1-master-8096acd7442e+ #8
  Hardware name: HP ProLiant DL360 Gen9/ProLiant DL360 Gen9, BIOS P89 09/13/2016
  Workqueue: inode_switch_wbs inode_switch_wbs_work_fn
  RIP: 0010:inode_do_switch_wbs+0xaf/0x470
  Code: 00 30 0f 85 c1 03 00 00 0f 1f 44 00 00 31 d2 48 c7 c6 ff ff ff ff 48 8d 7c 24 08 e8 eb 49 1a 00 48 85 c0 74 4a bb ff ff ff ff <48> 8b 50 08 48 8d 4a ff 83 e2 01 48 0f 45 c1 48 8b 00 a8 08 0f 85
  RSP: 0018:ffff9c66691abdc8 EFLAGS: 00010002
  RAX: 0000000005b0f661 RBX: 00000000ffffffff RCX: ffff89e6a21382b0
  RDX: 0000000000000001 RSI: ffff89e350230248 RDI: ffffffffffffffff
  RBP: ffff89e681d19400 R08: 0000000000000000 R09: 0000000000000228
  R10: ffffffffffffffff R11: ffffffffffffffc0 R12: ffff89e6a2138130
  R13: ffff89e316af7400 R14: ffff89e316af6e78 R15: ffff89e6a21382b0
  FS:  0000000000000000(0000) GS:ffff89ee5fb40000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000005b0f669 CR3: 0000000cb2410004 CR4: 00000000001706e0
  Call Trace:
   inode_switch_wbs_work_fn+0xb6/0x2a0
   process_one_work+0x1e6/0x380
   worker_thread+0x53/0x3d0
   kthread+0x10f/0x130
   ret_from_fork+0x22/0x30
  Modules linked in: xt_CHECKSUM xt_MASQUERADE xt_conntrack ipt_REJECT nf_reject_ipv4 nft_compat nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 nft_counter nf_tables nfnetlink bridge stp llc rfkill sunrpc intel_rapl_msr intel_rapl_common sb_edac x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel ipmi_ssif kvm mgag200 i2c_algo_bit iTCO_wdt irqbypass drm_kms_helper iTCO_vendor_support acpi_ipmi rapl syscopyarea sysfillrect intel_cstate ipmi_si sysimgblt ioatdma dax_pmem_compat fb_sys_fops ipmi_devintf device_dax i2c_i801 pcspkr intel_uncore hpilo nd_pmem cec dax_pmem_core dca i2c_smbus acpi_tad lpc_ich ipmi_msghandler acpi_power_meter drm fuse xfs libcrc32c sd_mod t10_pi crct10dif_pclmul crc32_pclmul crc32c_intel tg3 ghash_clmulni_intel serio_raw hpsa hpwdt scsi_transport_sas wmi dm_mirror dm_region_hash dm_log dm_mod
  CR2: 0000000005b0f669
  ---[ end trace ed2105faff8384f3 ]---
  RIP: 0010:inode_do_switch_wbs+0xaf/0x470
  Code: 00 30 0f 85 c1 03 00 00 0f 1f 44 00 00 31 d2 48 c7 c6 ff ff ff ff 48 8d 7c 24 08 e8 eb 49 1a 00 48 85 c0 74 4a bb ff ff ff ff <48> 8b 50 08 48 8d 4a ff 83 e2 01 48 0f 45 c1 48 8b 00 a8 08 0f 85
  RSP: 0018:ffff9c66691abdc8 EFLAGS: 00010002
  RAX: 0000000005b0f661 RBX: 00000000ffffffff RCX: ffff89e6a21382b0
  RDX: 0000000000000001 RSI: ffff89e350230248 RDI: ffffffffffffffff
  RBP: ffff89e681d19400 R08: 0000000000000000 R09: 0000000000000228
  R10: ffffffffffffffff R11: ffffffffffffffc0 R12: ffff89e6a2138130
  R13: ffff89e316af7400 R14: ffff89e316af6e78 R15: ffff89e6a21382b0
  FS:  0000000000000000(0000) GS:ffff89ee5fb40000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000005b0f669 CR3: 0000000cb2410004 CR4: 00000000001706e0
  Kernel panic - not syncing: Fatal exception
  Kernel Offset: 0x15200000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
  ---[ end Kernel panic - not syncing: Fatal exception ]---

The crash happens on an attempt to iterate over attached pagecache pages
and check the dirty flag: a dax inode's xarray contains pfn's instead of
generic struct page pointers.

This happens for DAX and not for other kinds of non-page entries in the
inodes because it's a tagged iteration, and shadow/swap entries are
never tagged; only DAX entries get tagged.

Fix the problem by bailing out (with the false return value) of
inode_prepare_sbs_switch() if a dax inode is passed.

[[email protected]: changelog addition]

Link: https://lkml.kernel.org/r/[email protected]
Fixes: c22d70a ("writeback, cgroup: release dying cgwbs by switching attached inodes")
Signed-off-by: Roman Gushchin <[email protected]>
Reported-by: Murphy Zhou <[email protected]>
Reported-by: Darrick J. Wong <[email protected]>
Tested-by: Darrick J. Wong <[email protected]>
Tested-by: Murphy Zhou <[email protected]>
Acked-by: Matthew Wilcox (Oracle) <[email protected]>
Cc: Jan Kara <[email protected]>
Cc: Dave Chinner <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
longlimsft pushed a commit that referenced this issue Nov 18, 2021
Replace GFP_KERNEL with GFP_ATOMIC as amdgpu_dm_irq_schedule_work
can't sleep.

BUG: sleeping function called from invalid context at include/linux/sched/mm.h:196
in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 253, name: kworker/6:1H
CPU: 6 PID: 253 Comm: kworker/6:1H Tainted: G        W  OE     5.11.0-promotion_2021_06_07-18_36_28_prelim_revert_retrain #8
Hardware name: System manufacturer System Product Name/PRIME X570-PRO, BIOS 3405 02/01/2021
Workqueue: events_highpri dm_irq_work_func [amdgpu]
Call Trace:
 <IRQ>
 dump_stack+0x5e/0x74
 ___might_sleep.cold+0x87/0x98
 __might_sleep+0x4b/0x80
 kmem_cache_alloc_trace+0x390/0x4f0
 amdgpu_dm_irq_handler+0x171/0x230 [amdgpu]
 amdgpu_irq_dispatch+0xc0/0x1e0 [amdgpu]
 amdgpu_ih_process+0x81/0x100 [amdgpu]
 amdgpu_irq_handler+0x26/0xa0 [amdgpu]
 __handle_irq_event_percpu+0x49/0x190
 ? __hrtimer_get_next_event+0x4d/0x80
 handle_irq_event_percpu+0x33/0x80
 handle_irq_event+0x33/0x60
 handle_edge_irq+0x82/0x190
 asm_call_irq_on_stack+0x12/0x20
 </IRQ>
 common_interrupt+0xbb/0x140
 asm_common_interrupt+0x1e/0x40
RIP: 0010:amdgpu_device_rreg.part.0+0x44/0xf0 [amdgpu]
Code: 53 48 89 fb 4c 3b af c8 08 00 00 73 6d 83 e2 02 75 0d f6 87 40 62 01 00 10 0f 85 83 00 00 00 4c 03 ab d0 08 00 00 45 8b 6d 00 <8b> 05 3e b6 52 00 85 c0 7e 62 48 8b 43 08 0f b7 70 3e 65 8b 05 e3
RSP: 0018:ffffae7740fff9e8 EFLAGS: 00000286
RAX: ffffffffc05ee610 RBX: ffff8aaf8f620000 RCX: 0000000000000006
RDX: 0000000000000000 RSI: 0000000000005430 RDI: ffff8aaf8f620000
RBP: ffffae7740fffa08 R08: 0000000000000001 R09: 000000000000000a
R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000005430
R13: 0000000071000000 R14: 0000000000000001 R15: 0000000000005430
 ? amdgpu_cgs_write_register+0x20/0x20 [amdgpu]
 amdgpu_device_rreg+0x17/0x20 [amdgpu]
 amdgpu_cgs_read_register+0x14/0x20 [amdgpu]
 dm_read_reg_func+0x38/0xb0 [amdgpu]
 generic_reg_wait+0x80/0x160 [amdgpu]
 dce_aux_transfer_raw+0x324/0x7c0 [amdgpu]
 dc_link_aux_transfer_raw+0x43/0x50 [amdgpu]
 dm_dp_aux_transfer+0x87/0x110 [amdgpu]
 drm_dp_dpcd_access+0x72/0x110 [drm_kms_helper]
 drm_dp_dpcd_read+0xb7/0xf0 [drm_kms_helper]
 drm_dp_get_one_sb_msg+0x349/0x480 [drm_kms_helper]
 drm_dp_mst_hpd_irq+0xc5/0xe40 [drm_kms_helper]
 ? drm_dp_mst_hpd_irq+0xc5/0xe40 [drm_kms_helper]
 dm_handle_hpd_rx_irq+0x184/0x1a0 [amdgpu]
 ? dm_handle_hpd_rx_irq+0x184/0x1a0 [amdgpu]
 handle_hpd_rx_irq+0x195/0x240 [amdgpu]
 ? __switch_to_asm+0x42/0x70
 ? __switch_to+0x131/0x450
 dm_irq_work_func+0x19/0x20 [amdgpu]
 process_one_work+0x209/0x400
 worker_thread+0x4d/0x3e0
 ? cancel_delayed_work+0xa0/0xa0
 kthread+0x124/0x160
 ? kthread_park+0x90/0x90
 ret_from_fork+0x22/0x30

Reviewed-by: Aurabindo Jayamohanan Pillai <[email protected]>
Acked-by: Anson Jacob <[email protected]>
Signed-off-by: Anson Jacob <[email protected]>
Cc: [email protected]
Tested-by: Daniel Wheeler <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>
longlimsft pushed a commit that referenced this issue Nov 18, 2021
When a virtio pci device undergo surprise removal (aka async removal in
PCIe spec), mark the device as broken so that any upper layer drivers can
abort any outstanding operation.

When a virtio net pci device undergo surprise removal which is used by a
NetworkManager, a below call trace was observed.

kernel:watchdog: BUG: soft lockup - CPU#1 stuck for 26s! [kworker/1:1:27059]
watchdog: BUG: soft lockup - CPU#1 stuck for 52s! [kworker/1:1:27059]
CPU: 1 PID: 27059 Comm: kworker/1:1 Tainted: G S      W I  L    5.13.0-hotplug+ #8
Hardware name: Dell Inc. PowerEdge R640/0H28RR, BIOS 2.9.4 11/06/2020
Workqueue: events linkwatch_event
RIP: 0010:virtnet_send_command+0xfc/0x150 [virtio_net]
Call Trace:
 virtnet_set_rx_mode+0xcf/0x2a7 [virtio_net]
 ? __hw_addr_create_ex+0x85/0xc0
 __dev_mc_add+0x72/0x80
 igmp6_group_added+0xa7/0xd0
 ipv6_mc_up+0x3c/0x60
 ipv6_find_idev+0x36/0x80
 addrconf_add_dev+0x1e/0xa0
 addrconf_dev_config+0x71/0x130
 addrconf_notify+0x1f5/0xb40
 ? rtnl_is_locked+0x11/0x20
 ? __switch_to_asm+0x42/0x70
 ? finish_task_switch+0xaf/0x2c0
 ? raw_notifier_call_chain+0x3e/0x50
 raw_notifier_call_chain+0x3e/0x50
 netdev_state_change+0x67/0x90
 linkwatch_do_dev+0x3c/0x50
 __linkwatch_run_queue+0xd2/0x220
 linkwatch_event+0x21/0x30
 process_one_work+0x1c8/0x370
 worker_thread+0x30/0x380
 ? process_one_work+0x370/0x370
 kthread+0x118/0x140
 ? set_kthread_struct+0x40/0x40
 ret_from_fork+0x1f/0x30

Hence, add the ability to abort the command on surprise removal
which prevents infinite loop and system lockup.

Signed-off-by: Parav Pandit <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Michael S. Tsirkin <[email protected]>
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
None yet
Projects
None yet
Development

No branches or pull requests

1 participant