Re: [Qemu-devel] [PATCH for-1.4] *-user: Don't reset X86CPU again

[Andreas Färber]

Am 21.01.2013 16:54, schrieb Igor Mammedov:
> On Sun, 20 Jan 2013 08:39:35 +0100
> Andreas Färber <address@hidden> wrote:
> Subj could be more specific, something along the lines:
>   Fix broken breakpoints duplication for i386-{bds,linux}-user

I agree I should expand to "linux-user: bsd-user: ..." at least, and I
intended it to carry qom-cpu tag since it's quite silent around
linux-user these days...

My endeavor here was purely reducing #ifdef'ery and not resolving a
particular bug. After all, ppc and sparc will still be broken; moving
their cpu_reset() into cpu_copy() to immediately after cpu_init() would
hopefully fix that.

Andreas

> 
>> Since commit 65dee38052597b6285eb208125369f01b29ba6c1 (target-i386:
>> move cpu_reset and reset callback to cpu.c) the x86 CPU is reset through
>> cpu_init() but was still reset immediately after in linux-user and
>> bsd-user. Similarly it was reset again in linux-user after cpu_copy(),
>> defeating its very purpose. Clean this up.
>>
>> Fixing the ppc and sparc cases of cpu_copy() and overhauling its
>> implementation is left for another day.
> Before b55a37c98 cpu_reset() was called at the end of cpu_init() and copying
> CPUState/duplicating breakpoints afterwards in cpu_copy() worked, BUT commit
> b4558d7481 breaks it, by positioning cpu_reset() call after copying
> CPUState/duplicating breakpoints. That should break as minimum breakpoints
> handling since they all should be duplicated on all CPUs and cpu_reset()
> deletes them explicitly.
> 
> From my POV patch fixes bug introduced by b4558d7481, Perhaps you should
> update commit message to mention this commit at least and what this patch
> fixes beside cleanups.
> 
> It would be nice though to get confirmation from Blue that all I've said above
> is not total nonsense.
> 
>>
>> Cc: Igor Mammedov <address@hidden>
>> Signed-off-by: Andreas Färber <address@hidden>
>> Cc: Peter Maydell <address@hidden>
>> ---
>>  bsd-user/main.c      |    2 +-
>>  linux-user/main.c    |    2 +-
>>  linux-user/syscall.c |    2 +-
>>  3 Dateien geändert, 3 Zeilen hinzugefügt(+), 3 Zeilen entfernt(-)
>>
>> diff --git a/bsd-user/main.c b/bsd-user/main.c
>> index 1dc0330..ae24723 100644
>> --- a/bsd-user/main.c
>> +++ b/bsd-user/main.c
>> @@ -917,7 +917,7 @@ int main(int argc, char **argv)
>>          fprintf(stderr, "Unable to find CPU definition\n");
>>          exit(1);
>>      }
>> -#if defined(TARGET_I386) || defined(TARGET_SPARC) || defined(TARGET_PPC)
>> +#if defined(TARGET_SPARC) || defined(TARGET_PPC)
>>      cpu_reset(ENV_GET_CPU(env));
>>  #endif
>>      thread_env = env;
>> diff --git a/linux-user/main.c b/linux-user/main.c
>> index 0181bc2..3df8aa2 100644
>> --- a/linux-user/main.c
>> +++ b/linux-user/main.c
>> @@ -3540,7 +3540,7 @@ int main(int argc, char **argv, char **envp)
>>          fprintf(stderr, "Unable to find CPU definition\n");
>>          exit(1);
>>      }
>> -#if defined(TARGET_I386) || defined(TARGET_SPARC) || defined(TARGET_PPC)
>> +#if defined(TARGET_SPARC) || defined(TARGET_PPC)
>>      cpu_reset(ENV_GET_CPU(env));
>>  #endif
>>  
>> diff --git a/linux-user/syscall.c b/linux-user/syscall.c
>> index 693e66f..7be6144 100644
>> --- a/linux-user/syscall.c
>> +++ b/linux-user/syscall.c
>> @@ -4361,7 +4361,7 @@ static int do_fork(CPUArchState *env, unsigned int
>> flags, abi_ulong newsp, init_task_state(ts);
>>          /* we create a new CPU instance. */
>>          new_env = cpu_copy(env);
>> -#if defined(TARGET_I386) || defined(TARGET_SPARC) || defined(TARGET_PPC)
>> +#if defined(TARGET_SPARC) || defined(TARGET_PPC)
>>          cpu_reset(ENV_GET_CPU(new_env));
>>  #endif
>>          /* Init regs that differ from the parent.  */
> 
> 


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