Re: [PATCH] xen x86: fix early boot crash with gcc-10

[Borislav Petkov]

On Mon, Apr 13, 2020 at 02:35:35PM +0200, FrÃdÃric Pierret (fepitre) wrote:
> The change fixes boot failure on VM where kernel (at least v5.4 and v5.6)
> is built with gcc-10 and STACKPROTECTOR_STRONG enabled:
> 
> ```
> Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: cpu_bringup_and_idle+0x93/0xa0
> CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.4.31-1.qubes.x86_64 #1
> Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.12.0-1 04/01/2014
> Call Trace:
>   dump_stack+0x64/0x88
>    panic+0x10b/0x2ed
>    ? cpu_bringup_and_idle+0x93/0xa0
>    __stack_chk_fail+0x15/0x20
>    cpu_bringup_and_idle+0x93/0xa
> ```
> The change makes successfully booting the VM. The VM is hosted by
> KVM hypervisor and is running Xen into.
> 
> Based on work done by Sergei Trofimovich: https://lkml.org/lkml/2020/3/26/1133

I was waiting for the merge window to finish to queue his patch. That is
done now, you can rebase yours ontop.

Thx.

-- 
Regards/Gruss,
    Boris.

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