kldload zfs spins the system after upgrading from 12.2 to 13-BETA

[Yoshihiro Ota]

On Sun, 7 Mar 2021 00:09:33 +0200
Andriy Gapon <avg at FreeBSD.org> wrote:

> On 06/03/2021 20:09, Yoshihiro Ota wrote:
> > Hi all,
> > 
> > I'm upgrading fron 12.2-RELEASE to 13-BETA/RC one by one.
> > 
> > After upgrading one in VMWare, 'zfs mount -a' hangs the system.
> > I don't have boottime zfs mount on nor don't have zfsroot.
> > I just simply ran install world/kernel and mergemaster.
> 
> Please use procstat -kk to capture a kernel stack trace of the hung process.

Actually, spining was 'kldload zfs'.
Console doesn't response but ping and sshd sessions still work.
procstat output is below.
In addition, this doesn't happen to systems that I've been following 13-CURRENT
but rather happen only wiht a system upgraded from 12.2-RELEASE to 13-RC.


# procstat -kk 1049
  PID    TID COMM                TDNAME              KSTACK                       
 1049 100215 kldload             -                   spa_init+0xc6 zfs_kmod_init+0x1a zfs_modevent+0x34 module_register_init+0x8c linker_load_module+0xaab kern_kldload+0xc1 sys_kldload+0x50 syscall+0x17d g_ctx+0xe280bf29