Re: [PATCH 1/1] hw/core/cpu: always print cpu index with cpu state

[Philippe Mathieu-Daudé]

On 7/2/23 00:42, Dongli Zhang wrote:
> The cpu_dump_state() does not print the cpu index. When the
> cpu_dump_state() is invoked due to the KVM failure, we are not able to tell
> from which CPU the state is. The below is an example.
>
> KVM internal error. Suberror: 764064
> RAX=0000000000000002 RBX=ffff8a9e57c38400 RCX=00000000ffffffff 
> RDX=ffff8a9cc00ba8a0
> RSI=0000000000000003 RDI=ffff8a9e57c38400 RBP=ffffb6120c5b3c50 
> RSP=ffffb6120c5b3c40
> R8 =0000000000000000 R9 =ffff8a9cc00ba8a0 R10=ffffffff8e467350 
> R11=0000000000000007
> R12=000000000000000a R13=ffffffff8f987e25 R14=ffffffff8f988a01 
> R15=0000000000000000
> RIP=ffffffff8e51bb04 RFL=00010046 [---Z-P-] CPL=0 II=0 A20=1 SMM=0 HLT=0
> ES =0000 0000000000000000 ffffffff 00c00000
> CS =0010 0000000000000000 ffffffff 00a09b00 DPL=0 CS64 [-RA]
> SS =0000 0000000000000000 ffffffff 00c00000
> DS =0000 0000000000000000 ffffffff 00c00000
> FS =0000 0000000000000000 ffffffff 00c00000
> GS =0000 ffff8ac27fcc0000 ffffffff 00c00000
> LDT=0000 0000000000000000 ffffffff 00c00000
> TR =0040 fffffe0000096000 0000206f 00008b00 DPL=0 TSS64-busy
> GDT=     fffffe0000094000 0000007f
> IDT=     fffffe0000000000 00000fff
> CR0=80050033 CR2=0000000000000000 CR3=00000010ca40a001 CR4=003606e0
> DR0=0000000000000000 DR1=0000000000000000 DR2=0000000000000000 
> DR3=0000000000000000
> DR6=00000000fffe0ff0 DR7=0000000000000400
> EFER=0000000000000d01
> Code=0f 1f ... ...
>
> Print the cpu->cpu_index in cpu_dump_state() and remove it from the caller.
>
> Cc: Joe Jin <joe.jin@oracle.com>
> Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com>
> ---
>   hw/core/cpu-common.c      | 1 +
>   monitor/hmp-cmds-target.c | 2 --
>   softmmu/cpus.c            | 1 -
>   3 files changed, 1 insertion(+), 3 deletions(-)
>
> diff --git a/hw/core/cpu-common.c b/hw/core/cpu-common.c
> index 5ccc3837b6..d2503f2d09 100644
> --- a/hw/core/cpu-common.c
> +++ b/hw/core/cpu-common.c
> @@ -105,6 +105,7 @@ void cpu_dump_state(CPUState *cpu, FILE *f, int flags)
>   
>       if (cc->dump_state) {
>           cpu_synchronize_state(cpu);

Should we check for:

          if (cpu->cpu_index != -1) {

> +        qemu_fprintf(f, "\nCPU#%d\n", cpu->cpu_index);

          }

?

>           cc->dump_state(cpu, f, flags);
>       }
>   }
> diff --git a/monitor/hmp-cmds-target.c b/monitor/hmp-cmds-target.c
> index 0d3e84d960..f7dd354d2a 100644
> --- a/monitor/hmp-cmds-target.c
> +++ b/monitor/hmp-cmds-target.c
> @@ -99,7 +99,6 @@ void hmp_info_registers(Monitor *mon, const QDict *qdict)
>   
>       if (all_cpus) {
>           CPU_FOREACH(cs) {
> -            monitor_printf(mon, "\nCPU#%d\n", cs->cpu_index);
>               cpu_dump_state(cs, NULL, CPU_DUMP_FPU);
>           }