Re: printk.time causes rare kernel boot hangs

From: Richard W.M. Jones
Date: Wed Jun 14 2023 - 09:05:09 EST


On Wed, Jun 14, 2023 at 02:53:20PM +0200, Peter Zijlstra wrote:
> Ooooh, what qemu version do you have? There were some really dodgy
> reports all around self modifying code, all reported on 7.2, that seems
> to have gone away with 8.

> Now, all of them were using TCG, and I think you're using KVM.

I'm using qemu-system-x86-8.0.0-4.fc39.x86_64 with KVM. The host
kernel is 6.4.0-0.rc5.41.fc39.x86_64.

> I've at least 36000 cycles and still nothing :-(, let me go try your
> .config.

I can definitely reproduce this with your config (but AMD host), so
that's odd. Let me try with Intel hardware and your config. You
really should see this with only a few thousands iterations.

Rich.

--
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