| Message ID | 20240828075630.7754-2-anisinha@redhat.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [v5,1/2] kvm: replace fprintf with error_report()/printf() in kvm_init() | expand |
Ani Sinha <anisinha@redhat.com> 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@nongnu.org > CC: zhao1.liu@intel.com > CC: armbru@redhat.com > 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. > 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@redhat.com>
> On 28 Aug 2024, at 4:53 PM, Markus Armbruster <armbru@redhat.com> wrote: > > Ani Sinha <anisinha@redhat.com> 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 You got this backwards. This is what I have: Before: $ ./qemu-system-x86_64 --accel kvm Could not access KVM kernel module: No such file or directory qemu-system-x86_64: --accel kvm: failed to initialize kvm: No such file or directory Now: $ ./qemu-system-x86_64 --accel kvm qemu-system-x86_64: --accel kvm: Could not access KVM kernel module: No such file or directory qemu-system-x86_64: --accel kvm: failed to initialize kvm: No such file or directory > > 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 Yes this seems correct. > >> CC: qemu-trivial@nongnu.org >> CC: zhao1.liu@intel.com >> CC: armbru@redhat.com >> 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. >> 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@redhat.com>
Ani Sinha <anisinha@redhat.com> writes: >> On 28 Aug 2024, at 4:53 PM, Markus Armbruster <armbru@redhat.com> wrote: >> >> Ani Sinha <anisinha@redhat.com> 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 > > You got this backwards. This is what I have: I do! Sorry %-} [...]
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)); #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; }