At present, the error code of MSR filter enablement is attempted to be
printed in error_report().
Unfortunately, this behavior doesn't work because the MSR filter-related
functions return the boolean and current error_report() use the wrong
return value.
So fix this by making MSR filter related functions return int type and
printing such returned value in error_report().
Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
---
target/i386/kvm/kvm.c | 35 +++++++++++++++++------------------
target/i386/kvm/kvm_i386.h | 4 ++--
2 files changed, 19 insertions(+), 20 deletions(-)
diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c
index 4aae4ffc9ccd..0fd1d099ae4c 100644
--- a/target/i386/kvm/kvm.c
+++ b/target/i386/kvm/kvm.c
@@ -2780,8 +2780,6 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
}
}
if (kvm_vm_check_extension(s, KVM_CAP_X86_USER_SPACE_MSR)) {
- bool r;
-
ret = kvm_vm_enable_cap(s, KVM_CAP_X86_USER_SPACE_MSR, 0,
KVM_MSR_EXIT_REASON_FILTER);
if (ret) {
@@ -2790,9 +2788,9 @@ int kvm_arch_init(MachineState *ms, KVMState *s)
exit(1);
}
- r = kvm_filter_msr(s, MSR_CORE_THREAD_COUNT,
- kvm_rdmsr_core_thread_count, NULL);
- if (!r) {
+ ret = kvm_filter_msr(s, MSR_CORE_THREAD_COUNT,
+ kvm_rdmsr_core_thread_count, NULL);
+ if (ret) {
error_report("Could not install MSR_CORE_THREAD_COUNT handler: %s",
strerror(-ret));
exit(1);
@@ -5274,13 +5272,13 @@ void kvm_arch_update_guest_debug(CPUState *cpu, struct kvm_guest_debug *dbg)
}
}
-static bool kvm_install_msr_filters(KVMState *s)
+static int kvm_install_msr_filters(KVMState *s)
{
uint64_t zero = 0;
struct kvm_msr_filter filter = {
.flags = KVM_MSR_FILTER_DEFAULT_ALLOW,
};
- int r, i, j = 0;
+ int ret, i, j = 0;
for (i = 0; i < KVM_MSR_FILTER_MAX_RANGES; i++) {
KVMMSRHandlers *handler = &msr_handlers[i];
@@ -5304,18 +5302,18 @@ static bool kvm_install_msr_filters(KVMState *s)
}
}
- r = kvm_vm_ioctl(s, KVM_X86_SET_MSR_FILTER, &filter);
- if (r) {
- return false;
+ ret = kvm_vm_ioctl(s, KVM_X86_SET_MSR_FILTER, &filter);
+ if (ret) {
+ return ret;
}
- return true;
+ return 0;
}
-bool kvm_filter_msr(KVMState *s, uint32_t msr, QEMURDMSRHandler *rdmsr,
- QEMUWRMSRHandler *wrmsr)
+int kvm_filter_msr(KVMState *s, uint32_t msr, QEMURDMSRHandler *rdmsr,
+ QEMUWRMSRHandler *wrmsr)
{
- int i;
+ int i, ret;
for (i = 0; i < ARRAY_SIZE(msr_handlers); i++) {
if (!msr_handlers[i].msr) {
@@ -5325,16 +5323,17 @@ bool kvm_filter_msr(KVMState *s, uint32_t msr, QEMURDMSRHandler *rdmsr,
.wrmsr = wrmsr,
};
- if (!kvm_install_msr_filters(s)) {
+ ret = kvm_install_msr_filters(s);
+ if (ret) {
msr_handlers[i] = (KVMMSRHandlers) { };
- return false;
+ return ret;
}
- return true;
+ return 0;
}
}
- return false;
+ return 0;
}
static int kvm_handle_rdmsr(X86CPU *cpu, struct kvm_run *run)
diff --git a/target/i386/kvm/kvm_i386.h b/target/i386/kvm/kvm_i386.h
index 34fc60774b86..91c2d6e69163 100644
--- a/target/i386/kvm/kvm_i386.h
+++ b/target/i386/kvm/kvm_i386.h
@@ -74,8 +74,8 @@ typedef struct kvm_msr_handlers {
QEMUWRMSRHandler *wrmsr;
} KVMMSRHandlers;
-bool kvm_filter_msr(KVMState *s, uint32_t msr, QEMURDMSRHandler *rdmsr,
- QEMUWRMSRHandler *wrmsr);
+int kvm_filter_msr(KVMState *s, uint32_t msr, QEMURDMSRHandler *rdmsr,
+ QEMUWRMSRHandler *wrmsr);
#endif /* CONFIG_KVM */
--
2.34.1
On 7/14/2024 9:49 PM, Zhao Liu wrote:
> @@ -5274,13 +5272,13 @@ void kvm_arch_update_guest_debug(CPUState *cpu, struct kvm_guest_debug *dbg)
> }
> }
>
> -static bool kvm_install_msr_filters(KVMState *s)
> +static int kvm_install_msr_filters(KVMState *s)
> {
> uint64_t zero = 0;
> struct kvm_msr_filter filter = {
> .flags = KVM_MSR_FILTER_DEFAULT_ALLOW,
> };
> - int r, i, j = 0;
> + int ret, i, j = 0;
>
> for (i = 0; i < KVM_MSR_FILTER_MAX_RANGES; i++) {
Nit: Since it's a clean up patch, how about replace
KVM_MSR_FILTER_MAX_RANGES with ARRAY_SIZE(msr_handlers), to make the
code consistent in other places to refer to the array size of
msr_handlers[].
> KVMMSRHandlers *handler = &msr_handlers[i];
> @@ -5304,18 +5302,18 @@ static bool kvm_install_msr_filters(KVMState *s)
> }
> }
>
> - r = kvm_vm_ioctl(s, KVM_X86_SET_MSR_FILTER, &filter);
> - if (r) {
> - return false;
> + ret = kvm_vm_ioctl(s, KVM_X86_SET_MSR_FILTER, &filter);
> + if (ret) {
> + return ret;
> }
>
> - return true;
> + return 0;
> }
Nit: Seems ret is not needed here, and can directly return kvm_vm_ioctl();
Hi Zide,
On Mon, Jul 15, 2024 at 03:18:07PM -0700, Chen, Zide wrote:
> Date: Mon, 15 Jul 2024 15:18:07 -0700
> From: "Chen, Zide" <zide.chen@intel.com>
> Subject: Re: [PATCH v3 7/8] target/i386/kvm: Clean up return values of MSR
> filter related functions
>
> On 7/14/2024 9:49 PM, Zhao Liu wrote:
> > @@ -5274,13 +5272,13 @@ void kvm_arch_update_guest_debug(CPUState *cpu, struct kvm_guest_debug *dbg)
> > }
> > }
> >
> > -static bool kvm_install_msr_filters(KVMState *s)
> > +static int kvm_install_msr_filters(KVMState *s)
> > {
> > uint64_t zero = 0;
> > struct kvm_msr_filter filter = {
> > .flags = KVM_MSR_FILTER_DEFAULT_ALLOW,
> > };
> > - int r, i, j = 0;
> > + int ret, i, j = 0;
> >
> > for (i = 0; i < KVM_MSR_FILTER_MAX_RANGES; i++) {
>
> Nit: Since it's a clean up patch, how about replace
> KVM_MSR_FILTER_MAX_RANGES with ARRAY_SIZE(msr_handlers), to make the
> code consistent in other places to refer to the array size of
> msr_handlers[].
Yes, that's fine, I'll add a new small trivial patch to clean up this.
> > KVMMSRHandlers *handler = &msr_handlers[i];
> > @@ -5304,18 +5302,18 @@ static bool kvm_install_msr_filters(KVMState *s)
> > }
> > }
> >
> > - r = kvm_vm_ioctl(s, KVM_X86_SET_MSR_FILTER, &filter);
> > - if (r) {
> > - return false;
> > + ret = kvm_vm_ioctl(s, KVM_X86_SET_MSR_FILTER, &filter);
> > + if (ret) {
> > + return ret;
> > }
> >
> > - return true;
> > + return 0;
> > }
>
> Nit: Seems ret is not needed here, and can directly return kvm_vm_ioctl();
Yes, good catch!
Thanks for you review!
Zhao
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