Re: [Qemu-devel] [PATCH] target-i386: Fix signedness of MSR_IA32_APICBASE_BASE

[Igor Mammedov]

On Fri, 29 May 2015 16:52:34 -0300
Eduardo Habkost <address@hidden> wrote:

> Existing definition triggers the following when using clang
> -fsanitize=undefined:
> 
>     hw/intc/apic_common.c:314:55: runtime error: left shift of 1048575 by 12
>         places cannot be represented in type 'int'
> 
> Fix it so we won't try to shift a 1 to the sign bit of a signed integer.
> 
> Suggested-by: Peter Maydell <address@hidden>
> Signed-off-by: Eduardo Habkost <address@hidden>
Reviewed-by: Igor Mammedov <address@hidden>

> ---
>  target-i386/cpu.h | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/target-i386/cpu.h b/target-i386/cpu.h
> index 4ee12ca..26182bd 100644
> --- a/target-i386/cpu.h
> +++ b/target-i386/cpu.h
> @@ -305,7 +305,7 @@
>  #define MSR_IA32_APICBASE               0x1b
>  #define MSR_IA32_APICBASE_BSP           (1<<8)
>  #define MSR_IA32_APICBASE_ENABLE        (1<<11)
> -#define MSR_IA32_APICBASE_BASE          (0xfffff<<12)
> +#define MSR_IA32_APICBASE_BASE          (0xfffffU<<12)
>  #define MSR_IA32_FEATURE_CONTROL        0x0000003a
>  #define MSR_TSC_ADJUST                  0x0000003b
>  #define MSR_IA32_TSCDEADLINE            0x6e0