Re: [PATCH] target/mips: Fix PageMask with variable page size

[Jiaxun Yang <jiaxun.yang@flygoat.com>]

在 2020/6/15 17:13, Peter Maydell 写道:
> On Sun, 14 Jun 2020 at 22:52, Aleksandar Markovic
> <aleksandar.qemu.devel@gmail.com> wrote:
>> When you change machine.c the way you did it, you need to bump the version. Please see git log on machine.c for details.
> 
>>> --- a/target/mips/cpu.h
>>> +++ b/target/mips/cpu.h
>>> @@ -617,7 +617,8 @@ struct CPUMIPSState {
>>>   /*
>>>    * CP0 Register 5
>>>    */
>>> -    int32_t CP0_PageMask;
>>> +    target_ulong CP0_PageMask;
>>> +#define CP0PM_MASK 13
> 
> Does CP0_PageMask ever actually hold a value that won't fit
> in an int32_t? If not, it might be preferable to avoid changing
> its type to avoid the migration compat break, even if MIPS
> doesn't have any versioned boards where we have a strict
> don't-break-compat promise to users.

In Release2, PageMask was extended to 64bit on MIPS64 processors.

Is it necessary to follow that?

Thanks.

> 
> thanks
> -- PMM
> 

-- 
- Jiaxun