Re: [PATCH 3/6] KVM: Remove opaque from kvm_arch_check_processor_compat

[Chao Gao]

On Mon, Jan 10, 2022 at 11:06:44PM +, Sean Christopherson wrote:
>On Mon, Dec 27, 2021, Chao Gao wrote:
>> No arch implementation uses this opaque now.
>
>Except for the RISC-V part, this can be a pure revert of commit b99040853738 
>("KVM:
>Pass kvm_init()'s opaque param to additional arch funcs").  I think it makes 
>sense
>to process it as a revert, with a short blurb in the changelog to note that 
>RISC-V
>is manually modified as RISC-V support came along in the interim.

commit b99040853738 adds opaque param to kvm_arch_hardware_setup(), which isn't
reverted in this patch. I.e., this patch is a partial revert of b99040853738
plus manual changes to RISC-V. Given that, "process it as a revert" means
clearly say in changelog that this commit contains a partial revert of commit
b99040853738 ("KVM: Pass kvm_init()'s opaque param to additional arch funcs").

Right?

[PATCH 3/6] KVM: Remove opaque from kvm_arch_check_processor_compat

[Chao Gao]

No arch implementation uses this opaque now.

Signed-off-by: Chao Gao 
---
 arch/arm64/kvm/arm.c   |  2 +-
 arch/mips/kvm/mips.c   |  2 +-
 arch/powerpc/kvm/powerpc.c |  2 +-
 arch/riscv/kvm/main.c  |  2 +-
 arch/s390/kvm/kvm-s390.c   |  2 +-
 arch/x86/kvm/x86.c |  2 +-
 include/linux/kvm_host.h   |  2 +-
 virt/kvm/kvm_main.c| 14 ++
 8 files changed, 9 insertions(+), 19 deletions(-)

diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index 14106a7c75b5..c196f005a2d3 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -73,7 +73,7 @@ int kvm_arch_hardware_setup(void *opaque)
return 0;
 }
 
-int kvm_arch_check_processor_compat(void *opaque)
+int kvm_arch_check_processor_compat(void)
 {
return 0;
 }
diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c
index e59cb6246f76..c5dc4fe53bfc 100644
--- a/arch/mips/kvm/mips.c
+++ b/arch/mips/kvm/mips.c
@@ -140,7 +140,7 @@ int kvm_arch_hardware_setup(void *opaque)
return 0;
 }
 
-int kvm_arch_check_processor_compat(void *opaque)
+int kvm_arch_check_processor_compat(void)
 {
return 0;
 }
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index 2ad0ccd202d5..30c817f3fa0c 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -423,7 +423,7 @@ int kvm_arch_hardware_setup(void *opaque)
return 0;
 }
 
-int kvm_arch_check_processor_compat(void *opaque)
+int kvm_arch_check_processor_compat(void)
 {
return kvmppc_core_check_processor_compat();
 }
diff --git a/arch/riscv/kvm/main.c b/arch/riscv/kvm/main.c
index 421ecf4e6360..3b0b104e443f 100644
--- a/arch/riscv/kvm/main.c
+++ b/arch/riscv/kvm/main.c
@@ -20,7 +20,7 @@ long kvm_arch_dev_ioctl(struct file *filp,
return -EINVAL;
 }
 
-int kvm_arch_check_processor_compat(void *opaque)
+int kvm_arch_check_processor_compat(void)
 {
return 0;
 }
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 9c6d45d0d345..99c70d881cb6 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -252,7 +252,7 @@ int kvm_arch_hardware_enable(void)
return 0;
 }
 
-int kvm_arch_check_processor_compat(void *opaque)
+int kvm_arch_check_processor_compat(void)
 {
return 0;
 }
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 770b68e72391..aa09c8792134 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -11380,7 +11380,7 @@ void kvm_arch_hardware_unsetup(void)
static_call(kvm_x86_hardware_unsetup)();
 }
 
-int kvm_arch_check_processor_compat(void *opaque)
+int kvm_arch_check_processor_compat(void)
 {
struct cpuinfo_x86 *c = _data(smp_processor_id());
 
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 05862176df6a..630ffd2289c6 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1307,7 +1307,7 @@ int kvm_arch_hardware_enable(void);
 void kvm_arch_hardware_disable(void);
 int kvm_arch_hardware_setup(void *opaque);
 void kvm_arch_hardware_unsetup(void);
-int kvm_arch_check_processor_compat(void *opaque);
+int kvm_arch_check_processor_compat(void);
 int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu);
 bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu);
 int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu);
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 168d0ab93c88..4e1e7770e984 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -5600,22 +5600,14 @@ struct kvm_vcpu * __percpu *kvm_get_running_vcpus(void)
 return _running_vcpu;
 }
 
-struct kvm_cpu_compat_check {
-   void *opaque;
-   int *ret;
-};
-
 static void check_processor_compat(void *data)
 {
-   struct kvm_cpu_compat_check *c = data;
-
-   *c->ret = kvm_arch_check_processor_compat(c->opaque);
+   *(int *)data = kvm_arch_check_processor_compat();
 }
 
 int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
  struct module *module)
 {
-   struct kvm_cpu_compat_check c;
int r;
int cpu;
 
@@ -5643,10 +5635,8 @@ int kvm_init(void *opaque, unsigned vcpu_size, unsigned 
vcpu_align,
if (r < 0)
goto out_free_1;
 
-   c.ret = 
-   c.opaque = opaque;
for_each_online_cpu(cpu) {
-   smp_call_function_single(cpu, check_processor_compat, , 1);
+   smp_call_function_single(cpu, check_processor_compat, , 1);
if (r < 0)
goto out_free_2;
}
-- 
2.25.1