On Thu, Jan 17, 2013 at 05:53:17PM +0000, David Vrabel wrote: > On 17/01/13 15:17, Daniel Kiper wrote: > > On Thu, Jan 17, 2013 at 02:50:26PM +0000, David Vrabel wrote: > >> On 17/01/13 12:28, Daniel Kiper wrote: > >>> On Wed, Jan 16, 2013 at 04:29:04PM +0000, David Vrabel wrote: > [..] > >>>> + if ( image->class == KEXEC_CLASS_32 ) > >>>> + compat_machine_kexec(image->entry_maddr); > >>> > >>> Why do you need that? > >> > >> image->class controls whether the processor is in 32-bit or 64-bit mode > >> when calling the image. The current implementation only allows images > >> to be executed with the same class as dom0. > >> > >> It's called class because that's the term ELF uses in the ELF header. > > > > As I correctly understand this sets processor mode before new kernel exection. > > If yes then it is not needed. Purgatory code (from kexec-tools) does all > > needed things. Please check. > > On x86 I think it would probably be fine to specify entry is always in Which entry? Kernel entry point? I think it is always the same. > 64-bit mode but for ARM and future architectures it is less clear and it > becomes more difficult to have a well-defined ABI. > > In fact, we probably want a more generic architecture field. e.g, > > #define XEN_KEXEC_ARCH_X86_32 0 > #define XEN_KEXEC_ARCH_X86_64 1 > #define XEN_KEXEC_ARCH_ARMv7 2 > #define XEN_KEXEC_ARCH_ARMv8 3 If we need them then please look into linux/include/uapi/linux/kexec.h. In Linux Kernel case they are passed via flags. Daniel
