Hi Mark, Thank you for your detailed report on the ath12k/WCN7850 5GHz scan failure on kernel 6.17.
I've investigated this issue and can confirm it's a known upstream regression affecting the Qualcomm FastConnect 7800 (WCN785x) Wi-Fi adapter when using Linux kernel 6.17+. The problem stems from frequency range filtering logic introduced in kernel 6.17 that breaks single-phy devices like yours. Good news: patches to fix this have been submitted to the linux-wireless mailing list by Saikiran B on January 23, 2026 and are currently under review. You can read the discussion here: https://lore.kernel.org/linux-wireless/[email protected]/T/#t In the meantime, your workaround of using kernel 6.14.0-37-generic is confirmed effective. Please continue using that kernel until an upstream fix is merged and backported to Ubuntu's stable releases. Thanks again for helping improve Ubuntu! ** Package changed: ubuntu => linux (Ubuntu) ** Changed in: linux (Ubuntu) Status: New => Confirmed -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2143056 Title: ath12k/WCN7850 (FastConnect 7800) 5GHz scan failure on kernel 6.17 -- works on 6.14 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2143056/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
