Re: [kvm-unit-tests PATCH 1/5] powerpc: add exception handler

[Thomas Huth <thuth@redhat.com>]

On 16.03.2016 16:12, Laurent Vivier wrote:
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
> ---
>  lib/powerpc/asm/hcall.h     |   1 +
>  lib/powerpc/asm/ppc_asm.h   |   5 ++
>  lib/powerpc/asm/processor.h |  11 ++++
>  lib/powerpc/processor.c     |  38 +++++++++++++
>  lib/powerpc/setup.c         |  19 +++++++
>  lib/ppc64/asm-offsets.c     |  42 ++++++++++++++
>  lib/ppc64/asm/processor.h   |   1 +
>  lib/ppc64/asm/ptrace.h      |  24 ++++++++
>  powerpc/Makefile.common     |   1 +
>  powerpc/cstart64.S          | 136 ++++++++++++++++++++++++++++++++++++++++++++
>  10 files changed, 278 insertions(+)
>  create mode 100644 lib/powerpc/asm/processor.h
>  create mode 100644 lib/powerpc/processor.c
>  create mode 100644 lib/ppc64/asm/processor.h
>  create mode 100644 lib/ppc64/asm/ptrace.h
...
> diff --git a/lib/powerpc/setup.c b/lib/powerpc/setup.c
> index 0c0c882..afe7fbc 100644
> --- a/lib/powerpc/setup.c
> +++ b/lib/powerpc/setup.c
> @@ -16,6 +16,8 @@
>  #include <alloc.h>
>  #include <asm/setup.h>
>  #include <asm/page.h>
> +#include <asm/ppc_asm.h>
> +#include <asm/hcall.h>
>  
>  extern unsigned long stacktop;
>  extern void io_init(void);
> @@ -33,6 +35,10 @@ struct cpu_set_params {
>  	unsigned dcache_bytes;
>  };
>  
> +#define EXCEPTION_STACK_SIZE	(32*1024) /* 32kB */
> +
> +static char exception_stack[NR_CPUS][EXCEPTION_STACK_SIZE];
> +
>  static void cpu_set(int fdtnode, u32 regval, void *info)
>  {
>  	static bool read_common_info = false;
> @@ -46,6 +52,11 @@ static void cpu_set(int fdtnode, u32 regval, void *info)
>  	}
>  	cpus[cpu] = regval;
>  
> +	/* set exception stack address for this CPU (in SPGR0) */
> +
> +	asm volatile ("mtsprg0 %[addr]" ::
> +		      [addr] "r" (exception_stack + cpu + 1));

Maybe use "exception_stack[cpu + 1]" instead? That's easier to read.

 Thomas