Re: [PATCH v3] kvm: replace fprintf with error_report/printf() in kvm_init()

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

Hi Ani,

On 9/8/24 08:49, Ani Sinha wrote:
> error_report() is more appropriate for error situations. Replace fprintf with
> error_report. Cosmetic. No functional change.
> 
> CC: qemu-trivial@nongnu.org
> CC: zhao1.liu@intel.com

(Pointless to carry Cc line when patch is already reviewed next line)

> Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
> Signed-off-by: Ani Sinha <anisinha@redhat.com>
> ---
>   accel/kvm/kvm-all.c | 40 ++++++++++++++++++----------------------
>   1 file changed, 18 insertions(+), 22 deletions(-)
> 
> changelog:
> v2: fix a bug.
> v3: replace one instance of error_report() with error_printf(). added tags.
> 
> diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
> index 75d11a07b2..5bc9d35b61 100644
> --- a/accel/kvm/kvm-all.c
> +++ b/accel/kvm/kvm-all.c
> @@ -2427,7 +2427,7 @@ static int kvm_init(MachineState *ms)
>       QLIST_INIT(&s->kvm_parked_vcpus);
>       s->fd = qemu_open_old(s->device ?: "/dev/kvm", O_RDWR);
>       if (s->fd == -1) {
> -        fprintf(stderr, "Could not access KVM kernel module: %m\n");
> +        error_report("Could not access KVM kernel module: %m");
>           ret = -errno;
>           goto err;
>       }
> @@ -2437,13 +2437,13 @@ static int kvm_init(MachineState *ms)
>           if (ret >= 0) {
>               ret = -EINVAL;
>           }
> -        fprintf(stderr, "kvm version too old\n");
> +        error_report("kvm version too old");
>           goto err;
>       }
>   
>       if (ret > KVM_API_VERSION) {
>           ret = -EINVAL;
> -        fprintf(stderr, "kvm version not supported\n");
> +        error_report("kvm version not supported");
>           goto err;
>       }
>   
> @@ -2488,26 +2488,22 @@ static int kvm_init(MachineState *ms)
>       } while (ret == -EINTR);
>   
>       if (ret < 0) {
> -        fprintf(stderr, "ioctl(KVM_CREATE_VM) failed: %d %s\n", -ret,
> -                strerror(-ret));
> +        error_report("ioctl(KVM_CREATE_VM) failed: %d %s", -ret,
> +                    strerror(-ret));
>   
>   #ifdef TARGET_S390X
>           if (ret == -EINVAL) {
> -            fprintf(stderr,
> -                    "Host kernel setup problem detected. Please verify:\n");
> -            fprintf(stderr, "- for kernels supporting the switch_amode or"
> -                    " user_mode parameters, whether\n");
> -            fprintf(stderr,
> -                    "  user space is running in primary address space\n");
> -            fprintf(stderr,
> -                    "- for kernels supporting the vm.allocate_pgste sysctl, "
> -                    "whether it is enabled\n");
> +            error_report("Host kernel setup problem detected.

\n"

Should we use error_printf_unless_qmp() for the following?

" Please verify:");
> +            error_report("- for kernels supporting the switch_amode or"
> +                        " user_mode parameters, whether");
> +            error_report("  user space is running in primary address space");
> +            error_report("- for kernels supporting the vm.allocate_pgste "
> +                        "sysctl, whether it is enabled");
>           }
>   #elif defined(TARGET_PPC)
>           if (ret == -EINVAL) {
> -            fprintf(stderr,
> -                    "PPC KVM module is not loaded.

\n"

Ditto.

" Try modprobe kvm_%s.\n",
> -                    (type == 2) ? "pr" : "hv");
> +            error_report("PPC KVM module is not loaded. Try modprobe kvm_%s.",
> +                        (type == 2) ? "pr" : "hv");
>           }
>   #endif
>           goto err;
> @@ -2526,9 +2522,9 @@ static int kvm_init(MachineState *ms)
>                           nc->name, nc->num, soft_vcpus_limit);
>   
>               if (nc->num > hard_vcpus_limit) {
> -                fprintf(stderr, "Number of %s cpus requested (%d) exceeds "
> -                        "the maximum cpus supported by KVM (%d)\n",
> -                        nc->name, nc->num, hard_vcpus_limit);
> +                error_report("Number of %s cpus requested (%d) exceeds "
> +                             "the maximum cpus supported by KVM (%d)",
> +                             nc->name, nc->num, hard_vcpus_limit);
>                   exit(1);
>               }
>           }
> @@ -2542,8 +2538,8 @@ static int kvm_init(MachineState *ms)
>       }
>       if (missing_cap) {
>           ret = -EINVAL;
> -        fprintf(stderr, "kvm does not support %s\n%s",
> -                missing_cap->name, upgrade_note);
> +        error_printf("kvm does not support %s\n%s",
> +                     missing_cap->name, upgrade_note);

Similarly, should we print upgrade_note using error_printf_unless_qmp?

>           goto err;
>       }
>