Ani Sinha <anisinha@xxxxxxxxxx> writes:
> error_report() is more appropriate for error situations. Replace fprintf with
> error_report() and error_printf() as appropriate. Cosmetic. No functional
> change.
Uh, I missed this last time around: the change is more than just
cosmetics! The error messages change, e.g. from
$ qemu-system-x86_64 -nodefaults -S -display none --accel kvm
qemu-system-x86_64: --accel kvm: Could not access KVM kernel module: Permission denied
qemu-system-x86_64: --accel kvm: failed to initialize kvm: Permission denied
to
$ qemu-system-x86_64 -nodefaults -S -display none --accel kvm
Could not access KVM kernel module: Permission denied
qemu-system-x86_64: --accel kvm: failed to initialize kvm: Permission denied
Note: the second message is from kvm_init()'s caller. Reporting the
same error twice is wrong, but not this patch's problem.
Moreover, the patch tweaks an error message at [*].
Suggest something like
Replace fprintf() with error_report() and error_printf() where
appropriate. Error messages improve, e.g. from
Could not access KVM kernel module: Permission denied
to
qemu-system-x86_64: --accel kvm: Could not access KVM kernel module: Permission denied
> CC: qemu-trivial@xxxxxxxxxx
> CC: zhao1.liu@xxxxxxxxx
> CC: armbru@xxxxxxxxxx
> Reviewed-by: Zhao Liu <zhao1.liu@xxxxxxxxx>
> Signed-off-by: Ani Sinha <anisinha@xxxxxxxxxx>
> ---
> 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.
> v4: changes suggested by Markus.
> v5: more changes from Markus's comments on v4.
>
> diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
> index 75d11a07b2..fcc157f0e6 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: %s", strerror(-ret));
[*] This is where you change an error message.
>
> #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_printf("Host kernel setup problem detected."
> + " Please verify:\n");
> + error_printf("- for kernels supporting the"
> + " switch_amode or user_mode parameters, whether");
> + error_printf(" user space is running in primary address space\n");
> + error_printf("- for kernels supporting the vm.allocate_pgste"
> + " sysctl, whether it is enabled\n");
> }
> #elif defined(TARGET_PPC)
> if (ret == -EINVAL) {
> - fprintf(stderr,
> - "PPC KVM module is not loaded. Try modprobe kvm_%s.\n",
> - (type == 2) ? "pr" : "hv");
> + error_printf("PPC KVM module is not loaded. Try modprobe kvm_%s.\n",
> + (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_report("kvm does not support %s", missing_cap->name);
> + error_printf("%s", upgrade_note);
> goto err;
> }
With the commit message corrected:
Reviewed-by: Markus Armbruster <armbru@xxxxxxxxxx>
