[PATCH net v3 0/3] dpll: fix unordered unbind/bind registerer issues

[Arkadiusz Kubalewski]

Fix issues when performing unordered unbind/bind of a kernel modules
which are using a dpll device with DPLL_PIN_TYPE_MUX pins.
Currently only serialized bind/unbind of such use case works, fix
the issues and allow for unserialized kernel module bind order.

The issues are observed on the ice driver, i.e.,

$ echo 0000:af:00.0 > /sys/bus/pci/drivers/ice/unbind
$ echo 0000:af:00.1 > /sys/bus/pci/drivers/ice/unbind

results in:

ice 0000:af:00.0: Removed PTP clock
BUG: kernel NULL pointer dereference, address: 0000000000000010
PF: supervisor read access in kernel mode
PF: error_code(0x0000) - not-present page
PGD 0 P4D 0 
Oops: 0000 [#1] PREEMPT SMP PTI
CPU: 7 PID: 71848 Comm: bash Kdump: loaded Not tainted 6.6.0-rc5_next-queue_19th-Oct-2023-01625-g039e5d15e451 #1
Hardware name: Intel Corporation S2600STB/S2600STB, BIOS SE5C620.86B.02.01.0008.031920191559 03/19/2019
RIP: 0010:ice_dpll_rclk_state_on_pin_get+0x2f/0x90 [ice]
Code: 41 57 4d 89 cf 41 56 41 55 4d 89 c5 41 54 55 48 89 f5 53 4c 8b 66 08 48 89 cb 4d 8d b4 24 f0 49 00 00 4c 89 f7 e8 71 ec 1f c5 <0f> b6 5b 10 41 0f b6 84 24 30 4b 00 00 29 c3 41 0f b6 84 24 28 4b
RSP: 0018:ffffc902b179fb60 EFLAGS: 00010246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffff8882c1398000 RSI: ffff888c7435cc60 RDI: ffff888c7435cb90
RBP: ffff888c7435cc60 R08: ffffc902b179fbb0 R09: 0000000000000000
R10: ffff888ef1fc8050 R11: fffffffffff82700 R12: ffff888c743581a0
R13: ffffc902b179fbb0 R14: ffff888c7435cb90 R15: 0000000000000000
FS:  00007fdc7dae0740(0000) GS:ffff888c105c0000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000010 CR3: 0000000132c24002 CR4: 00000000007706e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
 <TASK>
 ? __die+0x20/0x70
 ? page_fault_oops+0x76/0x170
 ? exc_page_fault+0x65/0x150
 ? asm_exc_page_fault+0x22/0x30
 ? ice_dpll_rclk_state_on_pin_get+0x2f/0x90 [ice]
 ? __pfx_ice_dpll_rclk_state_on_pin_get+0x10/0x10 [ice]
 dpll_msg_add_pin_parents+0x142/0x1d0
 dpll_pin_event_send+0x7d/0x150
 dpll_pin_on_pin_unregister+0x3f/0x100
 ice_dpll_deinit_pins+0xa1/0x230 [ice]
 ice_dpll_deinit+0x29/0xe0 [ice]
 ice_remove+0xcd/0x200 [ice]
 pci_device_remove+0x33/0xa0
 device_release_driver_internal+0x193/0x200
 unbind_store+0x9d/0xb0
 kernfs_fop_write_iter+0x128/0x1c0
 vfs_write+0x2bb/0x3e0
 ksys_write+0x5f/0xe0
 do_syscall_64+0x59/0x90
 ? filp_close+0x1b/0x30
 ? do_dup2+0x7d/0xd0
 ? syscall_exit_work+0x103/0x130
 ? syscall_exit_to_user_mode+0x22/0x40
 ? do_syscall_64+0x69/0x90
 ? syscall_exit_work+0x103/0x130
 ? syscall_exit_to_user_mode+0x22/0x40
 ? do_syscall_64+0x69/0x90
 entry_SYSCALL_64_after_hwframe+0x6e/0xd8
RIP: 0033:0x7fdc7d93eb97
Code: 0b 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24
RSP: 002b:00007fff2aa91028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000000000d RCX: 00007fdc7d93eb97
RDX: 000000000000000d RSI: 00005644814ec9b0 RDI: 0000000000000001
RBP: 00005644814ec9b0 R08: 0000000000000000 R09: 00007fdc7d9b14e0
R10: 00007fdc7d9b13e0 R11: 0000000000000246 R12: 000000000000000d
R13: 00007fdc7d9fb780 R14: 000000000000000d R15: 00007fdc7d9f69e0
 </TASK>
Modules linked in: uinput vfio_pci vfio_pci_core vfio_iommu_type1 vfio irqbypass ixgbevf snd_seq_dummy snd_hrtimer snd_seq snd_timer snd_seq_device snd soundcore overlay qrtr rfkill vfat fat xfs libcrc32c rpcrdma sunrpc rdma_ucm ib_srpt ib_isert iscsi_target_mod target_core_mod ib_iser libiscsi scsi_transport_iscsi rdma_cm iw_cm ib_cm intel_rapl_msr intel_rapl_common intel_uncore_frequency intel_uncore_frequency_common isst_if_common skx_edac nfit libnvdimm ipmi_ssif x86_pkg_temp_thermal intel_powerclamp coretemp irdma rapl intel_cstate ib_uverbs iTCO_wdt iTCO_vendor_support acpi_ipmi intel_uncore mei_me ipmi_si pcspkr i2c_i801 ib_core mei ipmi_devintf intel_pch_thermal ioatdma i2c_smbus ipmi_msghandler lpc_ich joydev acpi_power_meter acpi_pad ext4 mbcache jbd2 sd_mod t10_pi sg ast i2c_algo_bit drm_shmem_helper drm_kms_helper ice crct10dif_pclmul ixgbe crc32_pclmul drm crc32c_intel ahci i40e libahci ghash_clmulni_intel libata mdio dca gnss wmi fuse [last unloaded: iavf]
CR2: 0000000000000010

v3:
- Removed patch "[1/1] dpll: fix pin dump crash after module unbind",
  behavior fixed in [v3 3/3] patch.

Arkadiusz Kubalewski (3):
  dpll: fix pin dump crash for rebound module
  dpll: fix register pin with unregistered parent pin
  dpll: fix userspace availability of pins

 drivers/dpll/dpll_core.c    | 63 +++++++++++++++++++++++++++++++------
 drivers/dpll/dpll_core.h    |  4 +--
 drivers/dpll/dpll_netlink.c | 57 +++++++++++++++++++++++----------
 3 files changed, 97 insertions(+), 27 deletions(-)

-- 
2.38.1