Re: kexec reboot failed due to commit 75d090fd167ac

[Aaron Lu]

On Tue, Aug 29, 2023 at 07:14:59PM +0700, Bagas Sanjaya wrote:
> On Tue, Aug 29, 2023 at 07:48:16PM +0800, Aaron Lu wrote:
> > Hi Kirill,
> > 
> > Ever since v6.5-rc1, I found that I can not use kexec to reboot an Intel
> > SPR test machine. With git bisect, the first bad commit is 75d090fd167ac
> > ("x86/tdx: Add unaccepted memory support").
> > 
> > I have no idea why a tdx change would affect it, I'm not doing anything
> > related to tdx.
> > 
> > Any ideas?
> > 
> > The kernel config is attached, let me know if you need any other info.
> 
> Can you provide system logs (e.g. journalctl output) when attempting to
> reboot?

... ...
Aug 29 19:15:59 be3af2b6059f systemd-shutdown[1]: Syncing filesystems and block devices.
Aug 29 19:15:59 be3af2b6059f systemd-shutdown[1]: Sending SIGTERM to remaining processes...
Aug 29 19:16:00 be3af2b6059f systemd-journald[2629]: Journal stopped
-- Boot 7e5173842b8b4be581886ff25ad0c02f --
Aug 29 19:24:27 be3af2b6059f kernel: microcode: updated early: 0x2b000161 -> 0x2b000461, date = 2023-03-13
Aug 29 19:24:27 be3af2b6059f kernel: Linux version 6.3.8-100.fc37.x86_64 (mockbuild@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx)
Aug 29 19:24:27 be3af2b6059f kernel: Command line: BOOT_IMAGE=/boot/vmlinuz-6.3.8-100.fc37.x86_64 root=UUID=4381321e-e0>

First 3 lines are from the first kernel, then I attmpted to kexec reboot
to 6.4.0-rc5-00009-g75d090fd167a and remote console hanged with the
reboot message of the first kernel. After a while, I know kexec failed
so I power cycled the machine to boot into a distro kernel, that is the
last 3 lines. There is no trace of the failed boot.

I guess the kexeced kernel failed to start early in the boot process
so the log is probably only available in serial, if any. Unfortunately,
there is no serial support for this machine.

Thanks,
Aaron

> Anyway, thanks for the regression report. I'm adding it to regzbot:
> 
> #regzbot ^introduced: 75d090fd167aca
> #regzbot title: unable to reboot with kexec due to TDX unaccepted memory support
> 
> Thanks.
> 
> -- 
> An old man doll... just what I always wanted! - Clara