openwrt / openwrt/mt76

MT7915e rcu_shed self-detected stall on CPU

Open
#1,049 0 comments 0 reactions 0 assignees View on GitHub

Nobody has claimed this yet.

Dominant language
C
Stars
888
Forks
436
No merged PRs in 30d

Description

Using OpenWRT 24.10.5. Started getting crashes on my adapter. It is x86 openwrt in proxmox on intel CPU, with Wallys MT7915 DR7915.

Worked well for years and one day it just crashed

#716 may be related

Fri Jan 30 01:10:59 2026 kern.err kernel: [  754.402249] mt7915e 0000:03:0e.0: Retry message 00005aed (seq 7)
Fri Jan 30 01:11:02 2026 kern.err kernel: [  756.482209] mt7915e 0000:03:0e.0: Message 00005aed (seq 7) timeout
Fri Jan 30 01:11:03 2026 kern.err kernel: [  757.622051] mt7915e 0000:03:0e.0: Timeout for driver own
Fri Jan 30 01:11:23 2026 auth.info login[18859]: root login on 'tty1'
Fri Jan 30 01:12:03 2026 kern.err kernel: [  817.628720] rcu: INFO: rcu_sched self-detected stall on CPU
Fri Jan 30 01:12:03 2026 kern.err kernel: [  817.629192] rcu:   1-....: (5999 ticks this GP) idle=217c/1/0x4000000000000000 softirq=69615/69615 fqs=3000
Fri Jan 30 01:12:03 2026 kern.err kernel: [  817.629843] rcu:   (t=6000 jiffies g=49877 q=8517 ncpus=2)
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.630269] CPU: 1 PID: 1325 Comm: napi/phy0-539 Tainted: G           O       6.6.119 #0
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.630828] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-0-gea1b7a073390-prebuilt.qemu.org 04/01/2014
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.631567] RIP: 0010:0xffffffffa081d01b [mt76@000000001b568c01+0xc000]
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.632066] Code: Unable to access opcode bytes at 0xffffffffa081cff1.
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.632570] RSP: 0018:ffffc900000cced8 EFLAGS: 00000286
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.633000] RAX: 00000000ffffffff RBX: ffff888005392020 RCX: 00000000000d51f0
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.633535] RDX: 0000000000000000 RSI: ffffc900030d51f0 RDI: ffff888005392020
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.634059] RBP: ffffc900000ccf00 R08: 0000000000000000 R09: 0000000000000101
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.634594] R10: 0000000000000001 R11: ffffc900000ccff8 R12: 00000000000d51f0
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.635120] R13: ffff888005392020 R14: ffff888005392ef0 R15: ffff888005394af8
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.635659] FS:  0000000000000000(0000) GS:ffff88803ed00000(0000) knlGS:0000000000000000
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.636234] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.636706] CR2: ffffffffa081cff1 CR3: 000000000ac7c000 CR4: 0000000000350ee0
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.637241] Call Trace:
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.637553]  <IRQ>
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.637842]  ? 0xffffffffa08595ce [mt7915e@00000000d5d9e528+0x18000]
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.638342]  0xffffffffa08599d7 [mt7915e@00000000d5d9e528+0x18000]
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.638838]  0xffffffff810df738
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.639182]  0xffffffff810df78d
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.639534]  0xffffffff810df21c
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.639876]  ? 0xffffffff818c47c0
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.640225]  0xffffffff81aff8fb
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.640567]  0xffffffff810df11c
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.640911]  </IRQ>
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.641204]  <TASK>
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.641505]  0xffffffff810df82f
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.641842]  0xffffffff818c474d
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.642171]  ? 0xffffffff818c47c0
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.642528]  0xffffffff818c4828
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.642856]  0xffffffff810fea15
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.643205]  ? 0xffffffff810fe940
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.643571]  0xffffffff81042a98
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.643914]  ? 0xffffffff810fe940
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.644275]  0xffffffff8100242b
Fri Jan 30 01:12:03 2026 kern.warn kernel: [  817.644632]  </TASK>

Contributor guide

No contributing guide indexed for this repository

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

The report identifies the mt7915e driver, the napi/phy0-539 context, and a sequence of retry, message-timeout, and driver-own-timeout errors before the RCU stall. Start by comparing the behavior with related issue #716 and tracing that sequence in the mt76 driver. Done means identifying the cause of the stall and crash and verifying a fix or a reproducible diagnosis.

Written by the indexing model from the issue text.

Assessment

Tech stack
c, linux
Domain
networking, operating-systems
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Needs clarification
Newbie friendliness
30/100

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.