Re: [kvm-unit-tests v2 PATCH] powerpc: Fix running the kvm-unit-tests with recent versions of QEMU

On 12/6/22 12:08, Thomas Huth wrote:
> Starting with version 7.0, QEMU starts the pseries guests in 32-bit mode
> instead of 64-bit (see QEMU commit 6e3f09c28a - "spapr: Force 32bit when
> resetting a core"). This causes our test_64bit() in powerpc/emulator.c
> to fail. Let's switch to 64-bit in our startup code instead to fix the
> issue.
> 
> Signed-off-by: Thomas Huth <[email protected]>

Reviewed-by: Cédric Le Goater <[email protected]>

Thanks,

C.

> ---
>   lib/powerpc/asm/ppc_asm.h | 3 +++
>   powerpc/cstart64.S        | 6 ++++++
>   2 files changed, 9 insertions(+)
> 
> diff --git a/lib/powerpc/asm/ppc_asm.h b/lib/powerpc/asm/ppc_asm.h
> index 39620a39..1b85f6bb 100644
> --- a/lib/powerpc/asm/ppc_asm.h
> +++ b/lib/powerpc/asm/ppc_asm.h
> @@ -35,4 +35,7 @@
>   
>   #endif /* __BYTE_ORDER__ */
>   
> +/* Machine State Register definitions: */
> +#define MSR_SF_BIT	63			/* 64-bit mode */
> +
>   #endif /* _ASMPOWERPC_PPC_ASM_H */
> diff --git a/powerpc/cstart64.S b/powerpc/cstart64.S
> index 972851f9..34e39341 100644
> --- a/powerpc/cstart64.S
> +++ b/powerpc/cstart64.S
> @@ -23,6 +23,12 @@
>   .globl start
>   start:
>   	FIXUP_ENDIAN
> +	/* Switch to 64-bit mode */
> +	mfmsr	r1
> +	li	r2,1
> +	sldi	r2,r2,MSR_SF_BIT
> +	or	r1,r1,r2
> +	mtmsrd	r1
>   	/*
>   	 * We were loaded at QEMU's kernel load address, but we're not
>   	 * allowed to link there due to how QEMU deals with linker VMAs,