MT7921 Causing Kernel to Freeze after Reboot

5 messages, 2 authors, 2022-04-25 · open the first message on its own page

MT7921 Causing Kernel to Freeze after Reboot

From: Philippe Schenker <hidden>
Date: 2021-12-22 11:52:36

Hello

So I received a new notebook recently, this is a Lenovo P14s that has a
Mediatek 7961 network controller inside.

-----

03:00.0 Network controller: MEDIATEK Corp. Device 7961
	Subsystem: Lenovo Device e0bc
	Physical Slot: 0
	Flags: bus master, fast devsel, latency 0, IRQ 91, IOMMU group
13
	Memory at 870200000 (64-bit, prefetchable) [size=1M]
	Memory at 870300000 (64-bit, prefetchable) [size=16K]
	Memory at 870304000 (64-bit, prefetchable) [size=4K]
	Capabilities: <access denied>
	Kernel driver in use: mt7921e
	Kernel modules: mt7921e
------

I have the issue that on 5.16-rc6 kernel (also on other rcs) it is
always freezing after I issue a "reboot" command. "poweroff" followed by
a normal power-on works always.

Since it freezes and showing multiple Call Traces I included 4 logs in
the attachment, it certainly points always to mt76_dma functions.

One of the traces included down below. I would appreciate any help on
how to proceed in debugging this, I figure I ask first on here maybe
someone already has some good hints on where this is leading.

Philippe

-----


[   11.195349] Modules linked in: 8021q garp mrp stp llc qrtr cmac
algif_hash algif_skcipher af_alg bnep wireguard curve25519_x86_64
libchacha20poly1305 chacha_x86_64 poly1305_x86_64 libblake2s
blake2s_x86_64 libcurve25519_generic libchacha libblake2s_generic
ip6_udp_tunnel udp_tunnel uvcvideo btusb btrtl videobuf2_vmalloc joydev
videobuf2_memops btbcm mousedev videobuf2_v4l2 btintel videobuf2_common
bluetooth videodev mc ecdh_generic intel_rapl_msr mt7921e(+)
mt7921_common mt76_connac_lib intel_rapl_common mt76 snd_acp3x_rn
snd_soc_dmic snd_acp3x_pdm_dma snd_soc_core edac_mce_amd psmouse
snd_ctl_led serio_raw kvm_amd snd_hda_codec_realtek snd_compress atkbd
libps2 snd_hda_codec_generic snd_hda_codec_hdmi ac97_bus
snd_pcm_dmaengine kvm amdgpu mac80211 snd_hda_intel irqbypass
snd_intel_dspcfg crct10dif_pclmul snd_intel_sdw_acpi think_lmi
crc32_pclmul firmware_attributes_class wmi_bmof ghash_clmulni_intel
snd_hda_codec libarc4 aesni_intel snd_hda_core crypto_simd snd_hwdep
cryptd vfat fat
[   11.195370]  rapl cfg80211 pcspkr thinkpad_acpi snd_pcm sdhci_pci
tpm_crb cqhci ucsi_acpi sp5100_tco ledtrig_audio r8169 snd_timer
gpu_sched sdhci k10temp platform_profile typec_ucsi snd_pci_acp5x
i2c_piix4 snd drm_ttm_helper typec snd_rn_pci_acp3x i8042 xhci_pci
mmc_core ccp ttm snd_pci_acp3x xhci_pci_renesas rfkill realtek roles
soundcore wmi serio tpm_tis tpm_tis_core i2c_scmi video tpm mac_hid
acpi_cpufreq pinctrl_amd rng_core nfsd auth_rpcgss nfs_acl lockd grace
sunrpc ipmi_devintf ipmi_msghandler sg crypto_user fuse ip_tables
x_tables ext4 crc32c_generic crc32c_intel crc16 mbcache jbd2 ftdi_sio
[   11.195388] CPU: 9 PID: 391 Comm: systemd-udevd Tainted: G    B D W 
OE     5.16.0-1-MANJARO #1 e53f5ca75f8033ff8736c17597ec46c465c565c0
[   11.195390] Hardware name: LENOVO 21A0CTO1WW/21A0CTO1WW, BIOS
R1MET43W (1.13 ) 11/05/2021
[   11.195391] Call Trace:
[   11.195392]  <TASK>
[   11.195393]  dump_stack_lvl+0x48/0x66
[   11.195395]  bad_page.cold+0x63/0x94
[   11.195397]  free_pcppages_bulk+0x1f2/0x380
[   11.195400]  free_unref_page+0xbd/0x140
[   11.195402]  mt76_dma_rx_cleanup+0x94/0x120 [mt76
38914422533eea8f7de7062b22740222ae6696aa]
[   11.195406]  mt7921_wpdma_reset+0xbc/0x1c0 [mt7921e
c9c5ddc0c86616f123c90aadf837c5b1ca6179c1]
[   11.195410]  mt7921_register_device+0x32b/0x5e0 [mt7921_common
de62e6211a822ebe8196f9a6a704d937124a5fd7]
[   11.195413]  mt7921_pci_probe+0x1f1/0x230 [mt7921e
c9c5ddc0c86616f123c90aadf837c5b1ca6179c1]
[   11.195416]  ? __pm_runtime_resume+0x58/0x80
[   11.195418]  local_pci_probe+0x45/0x90
[   11.195419]  ? pci_match_device+0xdf/0x140
[   11.195421]  pci_device_probe+0xcf/0x1c0
[   11.195422]  really_probe+0x203/0x400
[   11.195424]  __driver_probe_device+0x112/0x190
[   11.195426]  driver_probe_device+0x1e/0x90
[   11.195427]  __driver_attach+0xc8/0x1e0
[   11.195428]  ? __device_attach_driver+0xf0/0xf0
[   11.195430]  ? __device_attach_driver+0xf0/0xf0
[   11.195431]  bus_for_each_dev+0x8d/0xe0
[   11.195432]  bus_add_driver+0x154/0x200
[   11.195434]  driver_register+0x8f/0xf0
[   11.195435]  ? 0xffffffffc05d1000
[   11.195436]  do_one_initcall+0x57/0x220
[   11.195438]  do_init_module+0x5c/0x270
[   11.195440]  load_module+0x25d7/0x27a0
[   11.195443]  ? __do_sys_init_module+0x12e/0x1b0
[   11.195444]  __do_sys_init_module+0x12e/0x1b0
[   11.195446]  do_syscall_64+0x5c/0x90
[   11.195448]  ? exc_page_fault+0x72/0x180
[   11.195451]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[   11.195453] RIP: 0033:0x7f765370732e
[   11.195454] Code: 48 8b 0d 45 0b 0c 00 f7 d8 64 89 01 48 83 c8 ff c3
66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 49 89 ca b8 af 00 00 00 0f
0[   12.234716] mt7921e 0000:03:00.0: Timeout for driver own

Re: MT7921 Causing Kernel to Freeze after Reboot

From: Íñigo Huguet <hidden>
Date: 2022-03-24 09:14:14

On Wed, Dec 22, 2021 at 12:52 PM Philippe Schenker [off-list ref] wrote:
Hello

So I received a new notebook recently, this is a Lenovo P14s that has a
Mediatek 7961 network controller inside.

-----

03:00.0 Network controller: MEDIATEK Corp. Device 7961
        Subsystem: Lenovo Device e0bc
        Physical Slot: 0
        Flags: bus master, fast devsel, latency 0, IRQ 91, IOMMU group
13
        Memory at 870200000 (64-bit, prefetchable) [size=1M]
        Memory at 870300000 (64-bit, prefetchable) [size=16K]
        Memory at 870304000 (64-bit, prefetchable) [size=4K]
        Capabilities: <access denied>
        Kernel driver in use: mt7921e
        Kernel modules: mt7921e
------

I have the issue that on 5.16-rc6 kernel (also on other rcs) it is
always freezing after I issue a "reboot" command. "poweroff" followed by
a normal power-on works always.
I have a bug report with this same behaviour and almost identical
kernel logs.: message "Timeout for driver own" followed by traces
related to mt7921 dma stuff, indicating bad page state with refcount
-1 and "page dumped because: nonzero _refcount", finally causing a
crash during boot up, but only after reboot, not after normal power
on.

It happens always, even with v5.17. Commit 602cc0c9618a (mt76:
mt7921e: fix possible probe failure after reboot) doesn't fix the
issue.

I hadn't been able to verify where the problem exactly is, but my guess is this:
- In function mt7921_init_hardware, initialization fails because
mt7921e_driver_own doesn't finish before the timeout (thus we see the
"Timeout for driver own")
- Then, before retrying to init, mt7921_init_hardware calls
mt7921e_init_reset, and the latter calls to mt7921_wpdma_reset
- That makes a cleanup of the DMA queues before stopping the DMA,
which had been enabled short before during probe
- Then, my guess is that in the meanwhile, a DMA event arrives with
the queues stillI being cleaned up

Does it make sense?
Since it freezes and showing multiple Call Traces I included 4 logs in
the attachment, it certainly points always to mt76_dma functions.

One of the traces included down below. I would appreciate any help on
how to proceed in debugging this, I figure I ask first on here maybe
someone already has some good hints on where this is leading.

Philippe

-----


[   11.195349] Modules linked in: 8021q garp mrp stp llc qrtr cmac
algif_hash algif_skcipher af_alg bnep wireguard curve25519_x86_64
libchacha20poly1305 chacha_x86_64 poly1305_x86_64 libblake2s
blake2s_x86_64 libcurve25519_generic libchacha libblake2s_generic
ip6_udp_tunnel udp_tunnel uvcvideo btusb btrtl videobuf2_vmalloc joydev
videobuf2_memops btbcm mousedev videobuf2_v4l2 btintel videobuf2_common
bluetooth videodev mc ecdh_generic intel_rapl_msr mt7921e(+)
mt7921_common mt76_connac_lib intel_rapl_common mt76 snd_acp3x_rn
snd_soc_dmic snd_acp3x_pdm_dma snd_soc_core edac_mce_amd psmouse
snd_ctl_led serio_raw kvm_amd snd_hda_codec_realtek snd_compress atkbd
libps2 snd_hda_codec_generic snd_hda_codec_hdmi ac97_bus
snd_pcm_dmaengine kvm amdgpu mac80211 snd_hda_intel irqbypass
snd_intel_dspcfg crct10dif_pclmul snd_intel_sdw_acpi think_lmi
crc32_pclmul firmware_attributes_class wmi_bmof ghash_clmulni_intel
snd_hda_codec libarc4 aesni_intel snd_hda_core crypto_simd snd_hwdep
cryptd vfat fat
[   11.195370]  rapl cfg80211 pcspkr thinkpad_acpi snd_pcm sdhci_pci
tpm_crb cqhci ucsi_acpi sp5100_tco ledtrig_audio r8169 snd_timer
gpu_sched sdhci k10temp platform_profile typec_ucsi snd_pci_acp5x
i2c_piix4 snd drm_ttm_helper typec snd_rn_pci_acp3x i8042 xhci_pci
mmc_core ccp ttm snd_pci_acp3x xhci_pci_renesas rfkill realtek roles
soundcore wmi serio tpm_tis tpm_tis_core i2c_scmi video tpm mac_hid
acpi_cpufreq pinctrl_amd rng_core nfsd auth_rpcgss nfs_acl lockd grace
sunrpc ipmi_devintf ipmi_msghandler sg crypto_user fuse ip_tables
x_tables ext4 crc32c_generic crc32c_intel crc16 mbcache jbd2 ftdi_sio
[   11.195388] CPU: 9 PID: 391 Comm: systemd-udevd Tainted: G    B D W
OE     5.16.0-1-MANJARO #1 e53f5ca75f8033ff8736c17597ec46c465c565c0
[   11.195390] Hardware name: LENOVO 21A0CTO1WW/21A0CTO1WW, BIOS
R1MET43W (1.13 ) 11/05/2021
[   11.195391] Call Trace:
[   11.195392]  <TASK>
[   11.195393]  dump_stack_lvl+0x48/0x66
[   11.195395]  bad_page.cold+0x63/0x94
[   11.195397]  free_pcppages_bulk+0x1f2/0x380
[   11.195400]  free_unref_page+0xbd/0x140
[   11.195402]  mt76_dma_rx_cleanup+0x94/0x120 [mt76
38914422533eea8f7de7062b22740222ae6696aa]
[   11.195406]  mt7921_wpdma_reset+0xbc/0x1c0 [mt7921e
c9c5ddc0c86616f123c90aadf837c5b1ca6179c1]
[   11.195410]  mt7921_register_device+0x32b/0x5e0 [mt7921_common
de62e6211a822ebe8196f9a6a704d937124a5fd7]
[   11.195413]  mt7921_pci_probe+0x1f1/0x230 [mt7921e
c9c5ddc0c86616f123c90aadf837c5b1ca6179c1]
[   11.195416]  ? __pm_runtime_resume+0x58/0x80
[   11.195418]  local_pci_probe+0x45/0x90
[   11.195419]  ? pci_match_device+0xdf/0x140
[   11.195421]  pci_device_probe+0xcf/0x1c0
[   11.195422]  really_probe+0x203/0x400
[   11.195424]  __driver_probe_device+0x112/0x190
[   11.195426]  driver_probe_device+0x1e/0x90
[   11.195427]  __driver_attach+0xc8/0x1e0
[   11.195428]  ? __device_attach_driver+0xf0/0xf0
[   11.195430]  ? __device_attach_driver+0xf0/0xf0
[   11.195431]  bus_for_each_dev+0x8d/0xe0
[   11.195432]  bus_add_driver+0x154/0x200
[   11.195434]  driver_register+0x8f/0xf0
[   11.195435]  ? 0xffffffffc05d1000
[   11.195436]  do_one_initcall+0x57/0x220
[   11.195438]  do_init_module+0x5c/0x270
[   11.195440]  load_module+0x25d7/0x27a0
[   11.195443]  ? __do_sys_init_module+0x12e/0x1b0
[   11.195444]  __do_sys_init_module+0x12e/0x1b0
[   11.195446]  do_syscall_64+0x5c/0x90
[   11.195448]  ? exc_page_fault+0x72/0x180
[   11.195451]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[   11.195453] RIP: 0033:0x7f765370732e
[   11.195454] Code: 48 8b 0d 45 0b 0c 00 f7 d8 64 89 01 48 83 c8 ff c3
66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 49 89 ca b8 af 00 00 00 0f
0[   12.234716] mt7921e 0000:03:00.0: Timeout for driver own

-- 
Íñigo Huguet

Re: MT7921 Causing Kernel to Freeze after Reboot

From: Philippe Schenker <hidden>
Date: 2022-04-01 11:24:36

On Thu, 2022-03-24 at 10:13 +0100, Íñigo Huguet wrote:
On Wed, Dec 22, 2021 at 12:52 PM Philippe Schenker [off-list ref]
wrote:
quoted
Hello

So I received a new notebook recently, this is a Lenovo P14s that
has a
Mediatek 7961 network controller inside.

-----

03:00.0 Network controller: MEDIATEK Corp. Device 7961
        Subsystem: Lenovo Device e0bc
        Physical Slot: 0
        Flags: bus master, fast devsel, latency 0, IRQ 91, IOMMU
group
13
        Memory at 870200000 (64-bit, prefetchable) [size=1M]
        Memory at 870300000 (64-bit, prefetchable) [size=16K]
        Memory at 870304000 (64-bit, prefetchable) [size=4K]
        Capabilities: <access denied>
        Kernel driver in use: mt7921e
        Kernel modules: mt7921e
------

I have the issue that on 5.16-rc6 kernel (also on other rcs) it is
always freezing after I issue a "reboot" command. "poweroff"
followed by
a normal power-on works always.
I have a bug report with this same behaviour and almost identical
kernel logs.: message "Timeout for driver own" followed by traces
related to mt7921 dma stuff, indicating bad page state with refcount
-1 and "page dumped because: nonzero _refcount", finally causing a
crash during boot up, but only after reboot, not after normal power
on.

It happens always, even with v5.17. Commit 602cc0c9618a (mt76:
mt7921e: fix possible probe failure after reboot) doesn't fix the
issue.

I hadn't been able to verify where the problem exactly is, but my
guess is this:
- In function mt7921_init_hardware, initialization fails because
mt7921e_driver_own doesn't finish before the timeout (thus we see the
"Timeout for driver own")
- Then, before retrying to init, mt7921_init_hardware calls
mt7921e_init_reset, and the latter calls to mt7921_wpdma_reset
- That makes a cleanup of the DMA queues before stopping the DMA,
which had been enabled short before during probe
- Then, my guess is that in the meanwhile, a DMA event arrives with
the queues stillI being cleaned up

Does it make sense?
After your suggestion I went down the rabbit-hole and bisected this
issue. Fortunately I found the commit introducing the issue. Reverting
this commit solves the problem for me on v5.17. It is caused around the
PCIe ASPM feature.

# first bad commit: [bf3747ae2e25dda6a9e6c464a717c66118c588c8] mt76:
mt7921: enable aspm by default

@Felix do I have to report this anywhere else than on here?

Thanks,
Philippe
quoted
Since it freezes and showing multiple Call Traces I included 4 logs
in
the attachment, it certainly points always to mt76_dma functions.

One of the traces included down below. I would appreciate any help
on
how to proceed in debugging this, I figure I ask first on here maybe
someone already has some good hints on where this is leading.

Philippe

-----


[   11.195349] Modules linked in: 8021q garp mrp stp llc qrtr cmac
algif_hash algif_skcipher af_alg bnep wireguard curve25519_x86_64
libchacha20poly1305 chacha_x86_64 poly1305_x86_64 libblake2s
blake2s_x86_64 libcurve25519_generic libchacha libblake2s_generic
ip6_udp_tunnel udp_tunnel uvcvideo btusb btrtl videobuf2_vmalloc
joydev
videobuf2_memops btbcm mousedev videobuf2_v4l2 btintel
videobuf2_common
bluetooth videodev mc ecdh_generic intel_rapl_msr mt7921e(+)
mt7921_common mt76_connac_lib intel_rapl_common mt76 snd_acp3x_rn
snd_soc_dmic snd_acp3x_pdm_dma snd_soc_core edac_mce_amd psmouse
snd_ctl_led serio_raw kvm_amd snd_hda_codec_realtek snd_compress
atkbd
libps2 snd_hda_codec_generic snd_hda_codec_hdmi ac97_bus
snd_pcm_dmaengine kvm amdgpu mac80211 snd_hda_intel irqbypass
snd_intel_dspcfg crct10dif_pclmul snd_intel_sdw_acpi think_lmi
crc32_pclmul firmware_attributes_class wmi_bmof ghash_clmulni_intel
snd_hda_codec libarc4 aesni_intel snd_hda_core crypto_simd snd_hwdep
cryptd vfat fat
[   11.195370]  rapl cfg80211 pcspkr thinkpad_acpi snd_pcm sdhci_pci
tpm_crb cqhci ucsi_acpi sp5100_tco ledtrig_audio r8169 snd_timer
gpu_sched sdhci k10temp platform_profile typec_ucsi snd_pci_acp5x
i2c_piix4 snd drm_ttm_helper typec snd_rn_pci_acp3x i8042 xhci_pci
mmc_core ccp ttm snd_pci_acp3x xhci_pci_renesas rfkill realtek roles
soundcore wmi serio tpm_tis tpm_tis_core i2c_scmi video tpm mac_hid
acpi_cpufreq pinctrl_amd rng_core nfsd auth_rpcgss nfs_acl lockd
grace
sunrpc ipmi_devintf ipmi_msghandler sg crypto_user fuse ip_tables
x_tables ext4 crc32c_generic crc32c_intel crc16 mbcache jbd2
ftdi_sio
[   11.195388] CPU: 9 PID: 391 Comm: systemd-udevd Tainted: G    B D
W
OE     5.16.0-1-MANJARO #1 e53f5ca75f8033ff8736c17597ec46c465c565c0
[   11.195390] Hardware name: LENOVO 21A0CTO1WW/21A0CTO1WW, BIOS
R1MET43W (1.13 ) 11/05/2021
[   11.195391] Call Trace:
[   11.195392]  <TASK>
[   11.195393]  dump_stack_lvl+0x48/0x66
[   11.195395]  bad_page.cold+0x63/0x94
[   11.195397]  free_pcppages_bulk+0x1f2/0x380
[   11.195400]  free_unref_page+0xbd/0x140
[   11.195402]  mt76_dma_rx_cleanup+0x94/0x120 [mt76
38914422533eea8f7de7062b22740222ae6696aa]
[   11.195406]  mt7921_wpdma_reset+0xbc/0x1c0 [mt7921e
c9c5ddc0c86616f123c90aadf837c5b1ca6179c1]
[   11.195410]  mt7921_register_device+0x32b/0x5e0 [mt7921_common
de62e6211a822ebe8196f9a6a704d937124a5fd7]
[   11.195413]  mt7921_pci_probe+0x1f1/0x230 [mt7921e
c9c5ddc0c86616f123c90aadf837c5b1ca6179c1]
[   11.195416]  ? __pm_runtime_resume+0x58/0x80
[   11.195418]  local_pci_probe+0x45/0x90
[   11.195419]  ? pci_match_device+0xdf/0x140
[   11.195421]  pci_device_probe+0xcf/0x1c0
[   11.195422]  really_probe+0x203/0x400
[   11.195424]  __driver_probe_device+0x112/0x190
[   11.195426]  driver_probe_device+0x1e/0x90
[   11.195427]  __driver_attach+0xc8/0x1e0
[   11.195428]  ? __device_attach_driver+0xf0/0xf0
[   11.195430]  ? __device_attach_driver+0xf0/0xf0
[   11.195431]  bus_for_each_dev+0x8d/0xe0
[   11.195432]  bus_add_driver+0x154/0x200
[   11.195434]  driver_register+0x8f/0xf0
[   11.195435]  ? 0xffffffffc05d1000
[   11.195436]  do_one_initcall+0x57/0x220
[   11.195438]  do_init_module+0x5c/0x270
[   11.195440]  load_module+0x25d7/0x27a0
[   11.195443]  ? __do_sys_init_module+0x12e/0x1b0
[   11.195444]  __do_sys_init_module+0x12e/0x1b0
[   11.195446]  do_syscall_64+0x5c/0x90
[   11.195448]  ? exc_page_fault+0x72/0x180
[   11.195451]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[   11.195453] RIP: 0033:0x7f765370732e
[   11.195454] Code: 48 8b 0d 45 0b 0c 00 f7 d8 64 89 01 48 83 c8 ff
c3
66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 49 89 ca b8 af 00 00 00
0f
0[   12.234716] mt7921e 0000:03:00.0: Timeout for driver own

Re: MT7921 Causing Kernel to Freeze after Reboot

From: Íñigo Huguet <hidden>
Date: 2022-04-25 10:39:12

On Thu, Mar 24, 2022 at 10:13 AM Íñigo Huguet [off-list ref] wrote:
On Wed, Dec 22, 2021 at 12:52 PM Philippe Schenker [off-list ref] wrote:
quoted
Hello

So I received a new notebook recently, this is a Lenovo P14s that has a
Mediatek 7961 network controller inside.

-----

03:00.0 Network controller: MEDIATEK Corp. Device 7961
        Subsystem: Lenovo Device e0bc
        Physical Slot: 0
        Flags: bus master, fast devsel, latency 0, IRQ 91, IOMMU group
13
        Memory at 870200000 (64-bit, prefetchable) [size=1M]
        Memory at 870300000 (64-bit, prefetchable) [size=16K]
        Memory at 870304000 (64-bit, prefetchable) [size=4K]
        Capabilities: <access denied>
        Kernel driver in use: mt7921e
        Kernel modules: mt7921e
------

I have the issue that on 5.16-rc6 kernel (also on other rcs) it is
always freezing after I issue a "reboot" command. "poweroff" followed by
a normal power-on works always.
I have a bug report with this same behaviour and almost identical
kernel logs.: message "Timeout for driver own" followed by traces
related to mt7921 dma stuff, indicating bad page state with refcount
-1 and "page dumped because: nonzero _refcount", finally causing a
crash during boot up, but only after reboot, not after normal power
on.

It happens always, even with v5.17. Commit 602cc0c9618a (mt76:
mt7921e: fix possible probe failure after reboot) doesn't fix the
issue.
Hi, a follow up with this. It seems that this commit does fix the issue for us.
602cc0c9618a (mt76: mt7921e: fix possible probe failure after reboot)

I don't know what we did wrong, but applying this single patch on top
of a non working one seems to work.

We'll test it a bit more to confirm, though.
I hadn't been able to verify where the problem exactly is, but my guess is this:
- In function mt7921_init_hardware, initialization fails because
mt7921e_driver_own doesn't finish before the timeout (thus we see the
"Timeout for driver own")
- Then, before retrying to init, mt7921_init_hardware calls
mt7921e_init_reset, and the latter calls to mt7921_wpdma_reset
- That makes a cleanup of the DMA queues before stopping the DMA,
which had been enabled short before during probe
- Then, my guess is that in the meanwhile, a DMA event arrives with
the queues stillI being cleaned up

Does it make sense?
quoted
Since it freezes and showing multiple Call Traces I included 4 logs in
the attachment, it certainly points always to mt76_dma functions.

One of the traces included down below. I would appreciate any help on
how to proceed in debugging this, I figure I ask first on here maybe
someone already has some good hints on where this is leading.

Philippe

-----


[   11.195349] Modules linked in: 8021q garp mrp stp llc qrtr cmac
algif_hash algif_skcipher af_alg bnep wireguard curve25519_x86_64
libchacha20poly1305 chacha_x86_64 poly1305_x86_64 libblake2s
blake2s_x86_64 libcurve25519_generic libchacha libblake2s_generic
ip6_udp_tunnel udp_tunnel uvcvideo btusb btrtl videobuf2_vmalloc joydev
videobuf2_memops btbcm mousedev videobuf2_v4l2 btintel videobuf2_common
bluetooth videodev mc ecdh_generic intel_rapl_msr mt7921e(+)
mt7921_common mt76_connac_lib intel_rapl_common mt76 snd_acp3x_rn
snd_soc_dmic snd_acp3x_pdm_dma snd_soc_core edac_mce_amd psmouse
snd_ctl_led serio_raw kvm_amd snd_hda_codec_realtek snd_compress atkbd
libps2 snd_hda_codec_generic snd_hda_codec_hdmi ac97_bus
snd_pcm_dmaengine kvm amdgpu mac80211 snd_hda_intel irqbypass
snd_intel_dspcfg crct10dif_pclmul snd_intel_sdw_acpi think_lmi
crc32_pclmul firmware_attributes_class wmi_bmof ghash_clmulni_intel
snd_hda_codec libarc4 aesni_intel snd_hda_core crypto_simd snd_hwdep
cryptd vfat fat
[   11.195370]  rapl cfg80211 pcspkr thinkpad_acpi snd_pcm sdhci_pci
tpm_crb cqhci ucsi_acpi sp5100_tco ledtrig_audio r8169 snd_timer
gpu_sched sdhci k10temp platform_profile typec_ucsi snd_pci_acp5x
i2c_piix4 snd drm_ttm_helper typec snd_rn_pci_acp3x i8042 xhci_pci
mmc_core ccp ttm snd_pci_acp3x xhci_pci_renesas rfkill realtek roles
soundcore wmi serio tpm_tis tpm_tis_core i2c_scmi video tpm mac_hid
acpi_cpufreq pinctrl_amd rng_core nfsd auth_rpcgss nfs_acl lockd grace
sunrpc ipmi_devintf ipmi_msghandler sg crypto_user fuse ip_tables
x_tables ext4 crc32c_generic crc32c_intel crc16 mbcache jbd2 ftdi_sio
[   11.195388] CPU: 9 PID: 391 Comm: systemd-udevd Tainted: G    B D W
OE     5.16.0-1-MANJARO #1 e53f5ca75f8033ff8736c17597ec46c465c565c0
[   11.195390] Hardware name: LENOVO 21A0CTO1WW/21A0CTO1WW, BIOS
R1MET43W (1.13 ) 11/05/2021
[   11.195391] Call Trace:
[   11.195392]  <TASK>
[   11.195393]  dump_stack_lvl+0x48/0x66
[   11.195395]  bad_page.cold+0x63/0x94
[   11.195397]  free_pcppages_bulk+0x1f2/0x380
[   11.195400]  free_unref_page+0xbd/0x140
[   11.195402]  mt76_dma_rx_cleanup+0x94/0x120 [mt76
38914422533eea8f7de7062b22740222ae6696aa]
[   11.195406]  mt7921_wpdma_reset+0xbc/0x1c0 [mt7921e
c9c5ddc0c86616f123c90aadf837c5b1ca6179c1]
[   11.195410]  mt7921_register_device+0x32b/0x5e0 [mt7921_common
de62e6211a822ebe8196f9a6a704d937124a5fd7]
[   11.195413]  mt7921_pci_probe+0x1f1/0x230 [mt7921e
c9c5ddc0c86616f123c90aadf837c5b1ca6179c1]
[   11.195416]  ? __pm_runtime_resume+0x58/0x80
[   11.195418]  local_pci_probe+0x45/0x90
[   11.195419]  ? pci_match_device+0xdf/0x140
[   11.195421]  pci_device_probe+0xcf/0x1c0
[   11.195422]  really_probe+0x203/0x400
[   11.195424]  __driver_probe_device+0x112/0x190
[   11.195426]  driver_probe_device+0x1e/0x90
[   11.195427]  __driver_attach+0xc8/0x1e0
[   11.195428]  ? __device_attach_driver+0xf0/0xf0
[   11.195430]  ? __device_attach_driver+0xf0/0xf0
[   11.195431]  bus_for_each_dev+0x8d/0xe0
[   11.195432]  bus_add_driver+0x154/0x200
[   11.195434]  driver_register+0x8f/0xf0
[   11.195435]  ? 0xffffffffc05d1000
[   11.195436]  do_one_initcall+0x57/0x220
[   11.195438]  do_init_module+0x5c/0x270
[   11.195440]  load_module+0x25d7/0x27a0
[   11.195443]  ? __do_sys_init_module+0x12e/0x1b0
[   11.195444]  __do_sys_init_module+0x12e/0x1b0
[   11.195446]  do_syscall_64+0x5c/0x90
[   11.195448]  ? exc_page_fault+0x72/0x180
[   11.195451]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[   11.195453] RIP: 0033:0x7f765370732e
[   11.195454] Code: 48 8b 0d 45 0b 0c 00 f7 d8 64 89 01 48 83 c8 ff c3
66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 49 89 ca b8 af 00 00 00 0f
0[   12.234716] mt7921e 0000:03:00.0: Timeout for driver own

--
Íñigo Huguet


-- 
Íñigo Huguet

Re: MT7921 Causing Kernel to Freeze after Reboot

From: Philippe Schenker <hidden>
Date: 2022-04-25 11:41:57

On Mon, 2022-04-25 at 12:38 +0200, Íñigo Huguet wrote:
On Thu, Mar 24, 2022 at 10:13 AM Íñigo Huguet [off-list ref]
wrote:
quoted
On Wed, Dec 22, 2021 at 12:52 PM Philippe Schenker
[off-list ref] wrote:
quoted
Hello

So I received a new notebook recently, this is a Lenovo P14s that
has a
Mediatek 7961 network controller inside.

-----

03:00.0 Network controller: MEDIATEK Corp. Device 7961
        Subsystem: Lenovo Device e0bc
        Physical Slot: 0
        Flags: bus master, fast devsel, latency 0, IRQ 91, IOMMU
group
13
        Memory at 870200000 (64-bit, prefetchable) [size=1M]
        Memory at 870300000 (64-bit, prefetchable) [size=16K]
        Memory at 870304000 (64-bit, prefetchable) [size=4K]
        Capabilities: <access denied>
        Kernel driver in use: mt7921e
        Kernel modules: mt7921e
------

I have the issue that on 5.16-rc6 kernel (also on other rcs) it is
always freezing after I issue a "reboot" command. "poweroff"
followed by
a normal power-on works always.
I have a bug report with this same behaviour and almost identical
kernel logs.: message "Timeout for driver own" followed by traces
related to mt7921 dma stuff, indicating bad page state with refcount
-1 and "page dumped because: nonzero _refcount", finally causing a
crash during boot up, but only after reboot, not after normal power
on.

It happens always, even with v5.17. Commit 602cc0c9618a (mt76:
mt7921e: fix possible probe failure after reboot) doesn't fix the
issue.
Hi, a follow up with this. It seems that this commit does fix the
issue for us.
602cc0c9618a (mt76: mt7921e: fix possible probe failure after reboot)

I don't know what we did wrong, but applying this single patch on top
of a non working one seems to work.

We'll test it a bit more to confirm, though.
Hello,

I also found that out in the meantime, sorry for not mentioning that
here. This issue was caused by

Commit bf3747ae2e25dd ("mt76: mt7921: enable aspm by default")

After finding this out I sent a revert, from which I was pointed to the
commit (602cc0c9618a) which fixes it also for me.

https://lore.kernel.org/linux-wireless/20220412090415.17541-1-dev@pschenker.ch/
quoted
I hadn't been able to verify where the problem exactly is, but my
guess is this:
- In function mt7921_init_hardware, initialization fails because
mt7921e_driver_own doesn't finish before the timeout (thus we see
the
"Timeout for driver own")
- Then, before retrying to init, mt7921_init_hardware calls
mt7921e_init_reset, and the latter calls to mt7921_wpdma_reset
- That makes a cleanup of the DMA queues before stopping the DMA,
which had been enabled short before during probe
- Then, my guess is that in the meanwhile, a DMA event arrives with
the queues stillI being cleaned up

Does it make sense?
quoted
Since it freezes and showing multiple Call Traces I included 4
logs in
the attachment, it certainly points always to mt76_dma functions.

One of the traces included down below. I would appreciate any help
on
how to proceed in debugging this, I figure I ask first on here
maybe
someone already has some good hints on where this is leading.

Philippe

-----


[   11.195349] Modules linked in: 8021q garp mrp stp llc qrtr cmac
algif_hash algif_skcipher af_alg bnep wireguard curve25519_x86_64
libchacha20poly1305 chacha_x86_64 poly1305_x86_64 libblake2s
blake2s_x86_64 libcurve25519_generic libchacha libblake2s_generic
ip6_udp_tunnel udp_tunnel uvcvideo btusb btrtl videobuf2_vmalloc
joydev
videobuf2_memops btbcm mousedev videobuf2_v4l2 btintel
videobuf2_common
bluetooth videodev mc ecdh_generic intel_rapl_msr mt7921e(+)
mt7921_common mt76_connac_lib intel_rapl_common mt76 snd_acp3x_rn
snd_soc_dmic snd_acp3x_pdm_dma snd_soc_core edac_mce_amd psmouse
snd_ctl_led serio_raw kvm_amd snd_hda_codec_realtek snd_compress
atkbd
libps2 snd_hda_codec_generic snd_hda_codec_hdmi ac97_bus
snd_pcm_dmaengine kvm amdgpu mac80211 snd_hda_intel irqbypass
snd_intel_dspcfg crct10dif_pclmul snd_intel_sdw_acpi think_lmi
crc32_pclmul firmware_attributes_class wmi_bmof
ghash_clmulni_intel
snd_hda_codec libarc4 aesni_intel snd_hda_core crypto_simd
snd_hwdep
cryptd vfat fat
[   11.195370]  rapl cfg80211 pcspkr thinkpad_acpi snd_pcm
sdhci_pci
tpm_crb cqhci ucsi_acpi sp5100_tco ledtrig_audio r8169 snd_timer
gpu_sched sdhci k10temp platform_profile typec_ucsi snd_pci_acp5x
i2c_piix4 snd drm_ttm_helper typec snd_rn_pci_acp3x i8042 xhci_pci
mmc_core ccp ttm snd_pci_acp3x xhci_pci_renesas rfkill realtek
roles
soundcore wmi serio tpm_tis tpm_tis_core i2c_scmi video tpm
mac_hid
acpi_cpufreq pinctrl_amd rng_core nfsd auth_rpcgss nfs_acl lockd
grace
sunrpc ipmi_devintf ipmi_msghandler sg crypto_user fuse ip_tables
x_tables ext4 crc32c_generic crc32c_intel crc16 mbcache jbd2
ftdi_sio
[   11.195388] CPU: 9 PID: 391 Comm: systemd-udevd Tainted: G    B
D W
OE     5.16.0-1-MANJARO #1
e53f5ca75f8033ff8736c17597ec46c465c565c0
[   11.195390] Hardware name: LENOVO 21A0CTO1WW/21A0CTO1WW, BIOS
R1MET43W (1.13 ) 11/05/2021
[   11.195391] Call Trace:
[   11.195392]  <TASK>
[   11.195393]  dump_stack_lvl+0x48/0x66
[   11.195395]  bad_page.cold+0x63/0x94
[   11.195397]  free_pcppages_bulk+0x1f2/0x380
[   11.195400]  free_unref_page+0xbd/0x140
[   11.195402]  mt76_dma_rx_cleanup+0x94/0x120 [mt76
38914422533eea8f7de7062b22740222ae6696aa]
[   11.195406]  mt7921_wpdma_reset+0xbc/0x1c0 [mt7921e
c9c5ddc0c86616f123c90aadf837c5b1ca6179c1]
[   11.195410]  mt7921_register_device+0x32b/0x5e0 [mt7921_common
de62e6211a822ebe8196f9a6a704d937124a5fd7]
[   11.195413]  mt7921_pci_probe+0x1f1/0x230 [mt7921e
c9c5ddc0c86616f123c90aadf837c5b1ca6179c1]
[   11.195416]  ? __pm_runtime_resume+0x58/0x80
[   11.195418]  local_pci_probe+0x45/0x90
[   11.195419]  ? pci_match_device+0xdf/0x140
[   11.195421]  pci_device_probe+0xcf/0x1c0
[   11.195422]  really_probe+0x203/0x400
[   11.195424]  __driver_probe_device+0x112/0x190
[   11.195426]  driver_probe_device+0x1e/0x90
[   11.195427]  __driver_attach+0xc8/0x1e0
[   11.195428]  ? __device_attach_driver+0xf0/0xf0
[   11.195430]  ? __device_attach_driver+0xf0/0xf0
[   11.195431]  bus_for_each_dev+0x8d/0xe0
[   11.195432]  bus_add_driver+0x154/0x200
[   11.195434]  driver_register+0x8f/0xf0
[   11.195435]  ? 0xffffffffc05d1000
[   11.195436]  do_one_initcall+0x57/0x220
[   11.195438]  do_init_module+0x5c/0x270
[   11.195440]  load_module+0x25d7/0x27a0
[   11.195443]  ? __do_sys_init_module+0x12e/0x1b0
[   11.195444]  __do_sys_init_module+0x12e/0x1b0
[   11.195446]  do_syscall_64+0x5c/0x90
[   11.195448]  ? exc_page_fault+0x72/0x180
[   11.195451]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[   11.195453] RIP: 0033:0x7f765370732e
[   11.195454] Code: 48 8b 0d 45 0b 0c 00 f7 d8 64 89 01 48 83 c8
ff c3
66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 49 89 ca b8 af 00 00
00 0f
0[   12.234716] mt7921e 0000:03:00.0: Timeout for driver own

--
Íñigo Huguet

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