On 02.12.2009, at 09:09, Aurelien Jarno wrote: > On Mon, Nov 30, 2009 at 11:19:06PM +0100, Alexander Graf wrote: >> >> On 30.11.2009, at 19:18, Aurelien Jarno wrote: >> >>> On Thu, Nov 26, 2009 at 02:23:15PM +0100, Alexander Graf wrote: >>>> Let's enable the basics for system emulation so we can run virtual machines >>>> with KVM! >>> >>> I don't really understand while this whole patch is not merged in patch >>> number 1. Otherwise, please find the comments below. >> >> Historical reasons. To keep Uli's stripped down version separate from my >> code. >> >>> >>>> Signed-off-by: Alexander Graf <ag...@suse.de> >>>> --- >>>> target-s390x/cpu.h | 153 >>>> ++++++++++++++++++++++++++++++++++++- >>>> target-s390x/exec.h | 5 + >>>> target-s390x/helper.c | 22 +++++ >>>> target-s390x/machine.c | 30 +++++++ >>>> 4 files changed, 208 insertions(+), 2 deletions(-) >>>> create mode 100644 default-configs/s390x-softmmu.mak >>>> create mode 100644 target-s390x/machine.c >>>> >>>> diff --git a/default-configs/s390x-softmmu.mak >>>> b/default-configs/s390x-softmmu.mak >>>> new file mode 100644 >>>> index 0000000..e69de29 >>>> diff --git a/target-s390x/cpu.h b/target-s390x/cpu.h >>>> index f45b00c..a74745c 100644 >>>> --- a/target-s390x/cpu.h >>>> +++ b/target-s390x/cpu.h >>>> @@ -30,8 +30,7 @@ >>>> >>>> #include "softfloat.h" >>>> >>>> -#define NB_MMU_MODES 2 // guess >>>> -#define MMU_USER_IDX 0 // guess >>>> +#define NB_MMU_MODES 2 >>>> >>>> typedef union FPReg { >>>> struct { >>>> @@ -77,6 +76,15 @@ static inline void cpu_clone_regs(CPUState *env, >>>> target_ulong newsp) >>>> } >>>> #endif >>>> >>>> +#define MMU_MODE0_SUFFIX _kernel >>>> +#define MMU_MODE1_SUFFIX _user >>>> +#define MMU_USER_IDX 1 >>>> +static inline int cpu_mmu_index (CPUState *env) >>>> +{ >>>> + /* XXX: Currently we don't implement virtual memory */ >>>> + return 0; >>> >>> Is it correct? It means that memory access will aways be kernel memory >>> accesses. IIRC, even with KVM enabled, softmmu accesses are possible in >>> some cases (devices ?). >> >> I can't imagine any hardware using the CPU's MMU to write to RAM. That's >> what IOMMUs are for. >> >> The only 2 consumers are: >> >> 1) tcg >> 2) gdb / monitor >> >> With 2) being broken, because we can't resolve virtual addresses to physical >> addresses. But that won't change until someone implements the softmmu >> emulation target for real. > > If it is sure it is never used, I would prefer to see an abort(). > Otherwise it's fine.
I don't think I understand where you want to put the abort(). Alex