Re: [BUG]smt sysfs dir missing on 4.4.148 and 4.14.63

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Thu, Aug 16, 2018 at 05:43:23PM +0200, Jinpu Wang wrote:
> Hi Greg, hi Thomas,
> 
> I noticed /sys/devices/system/cpu/smt dir is missing on 4.4.148 and
> 4.14.63, default setting.

For 4.4, I would be amazed if anything was there, the backport was done
only to handle the local user issue, not the "full" protection.  So
please try 4.9 or 4.14.

How about 4.17 and 4.18, do those trees work properly for you?

> Tried stable/master branch 31130a16d459 ("Merge tag
> 'for-linus-4.19-rc1-tag' of
> git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip")
> It's the same there.

Ah, so we are bug compatible, good :)

> When boot with 'nosmt' kernel paramter kernel 4.14.63 panic during
> boot, 4.4.148 boot fine.
> The call trace seem irq related, is it known bug?

You are not giving us much to go on here sorry.  We need full details,
and also please cc: lkml and the other developers who worked on this.
THomas is on vacation this week.

thanks,

greg k-h