VMAP_STACK is new on riscv since v5.14 kernel, meaning we haven't shipped any releases on riscv with VMAP_STACK enabled.
At the time when VMAP_STACK was enabled in the kernel nobody had EFI for riscv yet either. So it makes sense that this issue is being experienced by us just now, once we got all the pieces landing together. I would be in favour to disable VMAP_STACK, on riscv64 only, until we have more fixes to make it work better. -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux-riscv in Ubuntu. https://bugs.launchpad.net/bugs/1967130 Title: rcu_sched detected stalls on CPUs/tasks Status in linux-riscv package in Ubuntu: New Bug description: When running the riscv64 live installer (https://cdimage.ubuntu.com/ubuntu-server/daily-live/20220330/jammy- live-server-riscv64.iso) on the SiFive Unmatched board we reproducibly see rcu_sched stalls related to accessing the UEFI runtime: Mar 30 11:50:47 ubuntu-server kernel: [ 1313.451647] rcu: INFO: rcu_sched detected stalls on CPUs/tasks: Mar 30 11:50:47 ubuntu-server kernel: [ 1313.451673] rcu: 3-...0: (3 GPs behind) idle=d03/1/0x4000000000000000 softirq=85648/85648 fqs=7326 Mar 30 11:50:47 ubuntu-server kernel: [ 1313.451698] (detected by 0, t=15002 jiffies, g=155853, q=1286) Mar 30 11:50:47 ubuntu-server kernel: [ 1313.451712] Task dump for CPU 3: Mar 30 11:50:47 ubuntu-server kernel: [ 1313.451720] task:kworker/u8:1 state:R running task stack: 0 pid: 3715 ppid: 2 flags:0x00000008 Mar 30 11:50:47 ubuntu-server kernel: [ 1313.451750] Workqueue: efi_rts_wq efi_call_rts Mar 30 11:50:47 ubuntu-server kernel: [ 1313.451777] Call Trace: Mar 30 11:50:47 ubuntu-server kernel: [ 1313.451782] [<ffffffff809be1b6>] __schedule+0x226/0x644 uname -a: Linux ubuntu-server 5.15.0-1004-generic #4-Ubuntu SMP Wed Feb 9 18:17:33 UTC 2022 riscv64 riscv64 riscv64 GNU/Linux --- ProblemType: Bug Architecture: riscv64 DistroRelease: Ubuntu 22.04 Package: linux-image-generic 5.15.0.1004.4 PackageArchitecture: riscv64 ProcEnviron: TERM=vt220 PATH=(custom, no user) LANG=C.UTF-8 Uname: Linux 5.15.0-1004-generic riscv64 UserGroups: N/A _MarkForUpload: True To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-riscv/+bug/1967130/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
