Re: [Qemu-devel] [PATCH for-1.4 1/2] linux-user: Fix cpu_copy() usage

[Andreas Färber]

Am 30.01.2013 09:46, schrieb Igor Mammedov:
> On Wed, 30 Jan 2013 08:46:34 +0100
> Andreas Färber <address@hidden> wrote:
> 
>> Am 30.01.2013 08:18, schrieb Igor Mammedov:
>>> On Wed, 30 Jan 2013 01:34:18 +0100
>>> Andreas Färber <address@hidden> wrote:
>>>
>>>> Commit b4558d7481aefc865b0b52bf9b285ebcf2e8b59f ((x86/Sparc/PPC)-user:
>>>> fix cpu_copy) added a CPU reset after cpu_copy() inside linux-user code.
>>>> This reverses the register copying that cpu_copy() does.
>>>>
>>>> Clean this up by moving the cpu_reset() call to after cpu_init() but
>>>> before memcpy(). This matches the initial CPU creation in linux-user.
>>>>
>>>> Cc: Blue Swirl <address@hidden>
>>>> Signed-off-by: Andreas Färber <address@hidden>
>>>> Cc: Peter Maydell <address@hidden>
>>>> ---
>>>>  exec.c               |    6 ++++++
>>>>  linux-user/syscall.c |    3 ---
>>>>  2 Dateien geändert, 6 Zeilen hinzugefügt(+), 3 Zeilen entfernt(-)
>>>>
>>>> diff --git a/exec.c b/exec.c
>>>> index b85508b..8dfa458 100644
>>>> --- a/exec.c
>>>> +++ b/exec.c
>>>> @@ -537,6 +537,12 @@ CPUArchState *cpu_copy(CPUArchState *env)
>>>>      CPUWatchpoint *wp;
>>>>  #endif
>>>>  
>>>> +#ifdef CONFIG_USER_ONLY
>>> unnecessary ifdef-feniry here, cpu_copy() is linux-user only thing.
>>
>> It is currently used only by linux-user (and hopefully will stay that
>> way :)) but I don't see the code limited to CONFIG_USER_ONLY?
> If we don't have to have this define (i.e. nothing breaks without it), lets
> skip it.

I disagree.

> As alternative we could move cpu_copy() to linux-user as the only user of it,
> it will help to cleanup exec.c of uncommon code.

That's the plan mentioned in the cover letter. I'll wait if we get any
feedback from the linux-user maintainer. Problem is, syscall.c is a real
big mess and I don't want to make it more so. Plan was to split it up by
architecture but I have had other priorities and no volunteer stepped up.

Nothing breaks any more than it is by not applying this.

Andreas

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