Re: Wake-up from suspend to RAM broken under `retbleed=stuff`

From: Borislav Petkov
Date: Sun Jan 08 2023 - 06:33:20 EST


On Sun, Jan 08, 2023 at 03:07:48AM +0000, Joan Bruguera wrote:
> Wake-up from suspend to RAM seems broken under `retbleed=stuff`
> (the recently introduced call depth tracking mitigation, see:
> https://lore.kernel.org/lkml/f9fd86acac4f49bc8f90b403978e9df3@xxxxxxxxxxxxxxxx/t/)
> I can replicate it on both real hardware and QEMU (with and without KVM).
>
> It can replicate it by booting a fairly standard mainline kernel

Which version exactly?

> on QEMU with `init=/bin/bash` and then suspending to RAM with:
> echo "deep" > /sys/power/mem_sleep
> echo "mem" > /sys/power/state
> Then executing `system_wakeup` on the QEMU monitor causes the crash.

You probably need to share .config too because my tailored .config built with
latest tip/master works fine here.

--
Regards/Gruss,
Boris.

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