mt7925e Module Kernel Panic on Linux 6.19.0-rc1 #1023
Description
The mt7925e WiFi driver module causes a kernel panic with buffer overflow error during firmware loading on kernel 6.19.0-rc1. The system boots successfully up to the amdgpu initialization stage, then hangs at the Plymouth boot screen during mt7925_init_work execution. The system becomes unresponsive and requires force shutdown.
What is not working?
- Kernel 6.19.0-rc1 does not boot - System hangs at Plymouth splash screen
- WiFi hardware initialization fails - mt7925e module triggers kernel panic
- No graphical interface reached - Boot halts before reaching Graphical Interface target
Affected Hardware
- OS: CachyOS Linux
- Kernel: 6.19.0-rc1-1-cachyos-rc (PROBLEM) vs 6.18.2-2-cachyos (WORKING)
- Motherboard: ASRock X870E Taichi
- CPU: AMD Ryzen 7 9950X3D (32 cores)
- GPU: AMD Radeon RX 9070 XT
- WiFi Chipset: MediaTek MT7925 (mt7925e driver)
Error Details
Kernel Panic Message:
strnlen: detected buffer overflow: 17 byte read of buffer size 16
kernel BUG at lib/string_helpers.c:1043!
Oops: invalid opcode: 0000
Root Cause: Buffer overflow in mt76_connac2_load_patch() function when loading firmware during mt7925_init_work execution.
Does downgrading package X fix the issue?
Yes - Downgrading to kernel 6.18.2-2-cachyos fixes the issue completely. The mt7925e module works without problems on 6.18.2.
This is a regression specific to 6.19.0-rc1.
Temporary Workaround
Blacklisting the mt7925e module allows 6.19.0-rc1 to boot (but WiFi is disabled):
echo "blacklist mt7925e" | sudo tee /etc/modprobe.d/blacklist-mt7925e-temp.conf
sudo mkinitcpio -PHave you made modifications on your own?
Yes. During initial troubleshooting, the following changes were made:
- Removed ryzen_smu module - Out-of-tree module that was also causing issues
- Disabled amdgpu vm_manager parameter - Invalid parameter for 6.19.0-rc1
- Blacklisted mt7925e module - Workaround to allow system to boot
Only the mt7925e blacklist was necessary to resolve the boot issue. The other changes were unrelated to this specific bug.
Note: No modifications were made to the kernel source code itself.
Provide Logs
Relevant Kernel Panic Stack Trace (from journalctl -b -1)
dic 19 11:38:19 cachyos-x8664 kernel: strnlen: detected buffer overflow: 17 byte read of buffer size 16
dic 19 11:38:19 cachyos-x8664 kernel: Modules linked in: amd_atl intel_rapl_msr intel_rapl_common mt7925e snd_hda_codec_atihdmi snd_hda_codec_hdmi mt7925_common snd_usb_audio(+) mt792x_lib snd_hda_intel btusb snd_usbmidi_lib mt76_connac_lib btmtk snd_hda_codec mt76 btrtl snd_ump btbcm snd_hda_core kvm_amd spd5118 btintel [...]
dic 19 11:38:19 cachyos-x8664 kernel: CPU: 15 UID: 0 PID: 111 Comm: kworker/15:0 Tainted: G S 6.19.0-rc1-1-cachyos-rc #1 PREEMPT(full)
dic 19 11:38:19 cachyos-x8664 kernel: Workqueue: events mt7925_init_work [mt7925_common]
dic 19 11:38:19 cachyos-x8664 kernel: RIP: 0010:__fortify_report+0x44/0x50
dic 19 11:38:19 cachyos-x8664 kernel: Call Trace:
dic 19 11:38:19 cachyos-x8664 kernel: <TASK>
dic 19 11:38:19 cachyos-x8664 kernel: __fortify_panic+0xd/0xf
dic 19 11:38:19 cachyos-x8664 kernel: mt76_connac2_load_patch.cold+0x34/0x90a [mt76_connac_lib]
dic 19 11:38:19 cachyos-x8664 kernel: mt792x_load_firmware+0x39/0x160 [mt792x_lib]
dic 19 11:38:19 cachyos-x8664 kernel: mt7925_run_firmware+0x28/0x460 [mt7925_common]
dic 19 11:38:19 cachyos-x8664 kernel: mt7925e_mcu_init+0x65/0xa0 [mt7925e]
dic 19 11:38:19 cachyos-x8664 kernel: mt7925_init_work+0x37/0x1d0 [mt7925_common]
dic 19 11:38:19 cachyos-x8664 kernel: process_one_work+0x193/0x350
dic 19 11:38:19 cachyos-x8664 kernel: worker_thread+0x254/0x3a0
dic 19 11:38:19 cachyos-x8664 kernel: kthread+0xfc/0x240
dic 19 11:38:19 cachyos-x8664 kernel: ret_from_fork+0x244/0x280
dic 19 11:38:19 cachyos-x8664 kernel: </TASK>
dic 19 11:38:19 cachyos-x8664 kernel: kernel BUG at lib/string_helpers.c:1043!
dic 19 11:38:19 cachyos-x8664 kernel: Oops: invalid opcode: 0000 [#1] SMP NOPTI
System Information (inxi output equivalent)
System: CachyOS Linux
Kernel: 6.19.0-rc1-1-cachyos-rc (6.19.0-rc1) PREEMPT(full)
CPU: AMD Ryzen 7 9950X3D (32 cores, 32 threads)
Motherboard: ASRock X870E Taichi
GPU: AMD Radeon RX 9070 XT (amdgpu)
RAM: 64 GB DDR5
WiFi: MediaTek MT7925 (mt7925e driver)
Boot Type: UEFI Secure Boot enabled
Full journalctl Log (Previous Boot)
sudo journalctl -b -1 -p err[Relevant errors from previous boot showing the mt7925e panic]
Summary
Problem: mt7925e driver causes kernel panic in 6.19.0-rc1 due to buffer overflow in mt76_connac2_load_patch()
Kernel: 6.19.0-rc1-1-cachyos-rc (regressed from 6.18.2-2-cachyos)
Workaround: Blacklist mt7925e module (disables WiFi)
Status: Awaiting upstream fix or kernel patch for mt76 driver