[Bug 2170215] Re: MT7921K (mt7921e) severe packet loss on 7.0.0-38, works on 7.0.0-34

Not a kernel bug. The packet loss was caused by a weak wireless backhaul between two TP-Link Deco mesh units. After connecting the units with an Ethernet cable, there is 0% packet loss on 7.0.0-38 over both Wi-Fi and Ethernet. Sorry for the noise. ** Changed in: linux (Ubuntu) Status: New => Invalid -- You received this bug notification because you are subscribed to linux in Ubuntu. Matching subscriptions: Bgg, Bmail, Nb https://bugs.launchpad.net/bugs/2170215 Title: MT7921K (mt7921e) severe packet loss on 7.0.0-38, works on 7.0.0-34 Status in linux package in Ubuntu: Invalid Bug description: After upgrading to Ubuntu 26.04.1 LTS, Wi-Fi on a MediaTek MT7921K (Gigabyte GC-WBAX1200, driver mt7921e) has heavy packet loss. Pinging the local router (signal -41 dBm, 2.4 GHz): - kernel 7.0.0-38-generic: ~55% packet loss, latency spikes up to 450 ms - kernel 7.0.0-34-generic: ~7% packet loss, normal latency On 5 GHz the loss on 7.0.0-38 is 45-60%. Other devices on the same network work without problems. Already tried without success: disable_aspm=1, Wi-Fi power save off, Bluetooth disabled, locking to a single BSSID. Workaround: booting 7.0.0-34-generic. ProblemType: Bug DistroRelease: Ubuntu 26.04 Package: linux-image-7.0.0-38-generic 7.0.0-38.38 ProcVersionSignature: Ubuntu 7.0.0-38.38-generic 7.0.14 Uname: Linux 7.0.0-38-generic x86_64 ApportVersion: 2.34.1-0ubuntu0.1 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC1: darko 4935 F.... wireplumber /dev/snd/controlC0: darko 4935 F.... wireplumber /dev/snd/seq: darko 4916 F.... pipewire CasperMD5CheckResult: pass CurrentDesktop: ubuntu:GNOME Date: Thu Oct 8 18:16:53 2026 InstallationDate: Installed on 2025-11-10 (332 days ago) InstallationMedia: Ubuntu 24.04.3 LTS "Noble Numbat" - Release amd64 (20250805.1) MachineType: Gigabyte Technology Co., Ltd. X570 AORUS PRO ProcEnviron: LANG=en_US.UTF-8 PATH=(custom, no user) SHELL=/bin/bash TERM=xterm-256color XDG_RUNTIME_DIR=<set> ProcFB: 0 nvidia-drmdrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-7.0.0-38-generic root=UUID=90ed7cdb-1a4d-4848-b867-9f9d86f55577 ro quiet splash crashkernel=2G-4G:320M,4G-32G:512M,32G-64G:1024M,64G-128G:2048M,128G-:4096M SourcePackage: linux UpgradeStatus: Upgraded to resolute on 2026-10-08 (0 days ago) dmi.bios.date: 03/22/2024 dmi.bios.release: 5.17 dmi.bios.vendor: American Megatrends International, LLC. dmi.bios.version: F38 dmi.board.asset.tag: Default string dmi.board.name: X570 AORUS PRO dmi.board.vendor: Gigabyte Technology Co., Ltd. dmi.board.version: Default string dmi.chassis.asset.tag: Default string dmi.chassis.type: 3 dmi.chassis.vendor: Default string dmi.chassis.version: Default string dmi.modalias: dmi:bvnAmericanMegatrendsInternational,LLC.:bvrF38:bd03/22/2024:br5.17:svnGigabyteTechnologyCo.,Ltd.:pnX570AORUSPRO:pvr-CF:rvnGigabyteTechnologyCo.,Ltd.:rnX570AORUSPRO:rvrDefaultstring:cvnDefaultstring:ct3:cvrDefaultstring:skuDefaultstring:pfaX570MB: dmi.product.family: X570 MB dmi.product.name: X570 AORUS PRO dmi.product.sku: Default string dmi.product.version: -CF dmi.sys.vendor: Gigabyte Technology Co., Ltd. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2170215/+subscriptions