On Thu, Mar 16, 2023 at 11:18:21AM +0100, Ard Biesheuvel wrote: > On Thu, 16 Mar 2023 at 11:03, Andrea Righi <andrea.righi@xxxxxxxxxxxxx> wrote: > > > > On Thu, Mar 16, 2023 at 10:55:58AM +0100, Ard Biesheuvel wrote: > > > (cc Darren) > > > > > > On Thu, 16 Mar 2023 at 10:45, Andrea Righi <andrea.righi@xxxxxxxxxxxxx> wrote: > > > > > > > > On Thu, Mar 16, 2023 at 08:58:20AM +0100, Ard Biesheuvel wrote: > > > > > Hello Andrea, > > > > > > > > > > On Thu, 16 Mar 2023 at 08:54, Andrea Righi <andrea.righi@xxxxxxxxxxxxx> wrote: > > > > > > > > > > > > Hello, > > > > > > > > > > > > the latest v6.2.6 kernel fails to boot on some arm64 systems, the kernel > > > > > > gets stuck and never completes the boot. On the console I see this: > > > > > > > > > > > > [ 72.043484] rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: > > > > > > [ 72.049571] rcu: 22-...0: (30 GPs behind) idle=b10c/1/0x4000000000000000 softirq=164/164 fqs=6443 > > > > > > [ 72.058520] (detected by 28, t=15005 jiffies, g=449, q=174 ncpus=32) > > > > > > [ 72.064949] Task dump for CPU 22: > > > > > > [ 72.068251] task:kworker/u64:5 state:R running task stack:0 pid:447 ppid:2 flags:0x0000000a > > > > > > [ 72.078156] Workqueue: efi_rts_wq efi_call_rts > > > > > > [ 72.082595] Call trace: > > > > > > [ 72.085029] __switch_to+0xbc/0x100 > > > > > > [ 72.088508] 0xffff80000fe83d4c > > > > > > > > > > > > After that, as a consequence, I start to get a lot of hung task timeout traces. > > > > > > > > > > > > I tried to bisect the problem and I found that the offending commit is > > > > > > this one: > > > > > > > > > > > > e7b813b32a42 ("efi: random: refresh non-volatile random seed when RNG is initialized") > > > > > > > > > > > > I've reverted this commit for now and everything works just fine, but I > > > > > > was wondering if the problem could be caused by a lack of entropy on > > > > > > these arm64 boxes or something else. > > > > > > > > > > > > Any suggestion? Let me know if you want me to do any specific test. > > > > > > > > > > > > > > > > Thanks for the report. > > > > > > > > > > This is most likely the EFI SetVariable() call going off into the > > > > > weeds and never returning. > > > > > > > > > > Is this an Ampere Altra system by any chance? Do you see it on > > > > > different types of hardware? > > > > > > > > This is: Ampere eMAG / Lenovo ThinkSystem HR330a. > > > > > > > > > > > > > > Could you check whether SetVariable works on this system? E.g. by > > > > > updating the EFI boot timeout (sudo efibootmgr -t <n>)? > > > > > > > > ubuntu@kuzzle:~$ sudo efibootmgr -t 10 > > > > ^C^C^C^C > > > > > > > > ^ Stuck there, so it really looks like SetVariable is the problem. > > > > > > > > > > Could you please share the output of > > > > > > dmidecode -s bios > > > dmidecode -s system-family > > > > $ sudo dmidecode -s bios-vendor > > LENOVO > > $ sudo dmidecode -s bios-version > > hve104r-1.15 > > $ sudo dmidecode -s bios-release-date > > 02/26/2021 > > $ sudo dmidecode -s bios-revision > > 1.15 > > $ sudo dmidecode -s system-family > > Lenovo ThinkSystem HR330A/HR350A > > > > Thanks > > Mind checking if this patch fixes your issue as well? > > https://git.kernel.org/pub/scm/linux/kernel/git/ardb/linux.git/commit/?h=altra-fix&id=77fa99dd4741456da85049c13ec31a148f5f5ac0 Unfortunately this doesn't seem to be enough, I'm still getting the same problem also with this patch applied. -Andrea