On Mon, 2022-06-27 at 14:52 -0700, isaku.yamahata@xxxxxxxxx wrote:
> From: Chao Gao <chao.gao@xxxxxxxxx>
>
> This partially reverts commit b99040853738 ("KVM: Pass kvm_init()'s opaque
> param to additional arch funcs") remove opaque from
> kvm_arch_check_processor_compat because no one uses this opaque now.
> Address conflicts for ARM (due to file movement) and manually handle RISC-V
> which comes after the commit.
>
> And changes about kvm_arch_hardware_setup() in original commit are still
> needed so they are not reverted.
I tried to dig the history to find out why we are doing this.
IMHO it's better to give a reason why you need to revert the opaque. I guess no
one uses this opaque now doesn't mean we need to remove it?
Perhaps you should mention this is a preparation to
hardware_enable_all()/hardware_disable_all() during module loading time.
Instead of extending hardware_enable_all()/hardware_disable_all() to take the
opaque and pass to kvm_arch_check_process_compat(), just remove the opaque.
Or perhaps just merge this patch to next one?
>
> Signed-off-by: Chao Gao <chao.gao@xxxxxxxxx>
> Reviewed-by: Sean Christopherson <seanjc@xxxxxxxxxx>
> Reviewed-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
> Acked-by: Anup Patel <anup@xxxxxxxxxxxxxx>
> Acked-by: Claudio Imbrenda <imbrenda@xxxxxxxxxxxxx>
> Link: https://lore.kernel.org/r/20220216031528.92558-3-chao.gao@xxxxxxxxx
> Signed-off-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
> ---
> 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 | 16 +++-------------
> 8 files changed, 10 insertions(+), 20 deletions(-)
>
> diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
> index a0188144a122..7588efbac6be 100644
> --- a/arch/arm64/kvm/arm.c
> +++ b/arch/arm64/kvm/arm.c
> @@ -68,7 +68,7 @@ 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 a25e0b73ee70..092d09fb6a7e 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 191992fcb2c2..ca8ef51092c6 100644
> --- a/arch/powerpc/kvm/powerpc.c
> +++ b/arch/powerpc/kvm/powerpc.c
> @@ -446,7 +446,7 @@ 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 1549205fe5fe..f8d6372d208f 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 72bd5c9b9617..a05493f1cacf 100644
> --- a/arch/s390/kvm/kvm-s390.c
> +++ b/arch/s390/kvm/kvm-s390.c
> @@ -251,7 +251,7 @@ 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 3d9dbaf9828f..30af2bd0b4d5 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -11799,7 +11799,7 @@ 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 = &cpu_data(smp_processor_id());
>
> diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
> index c20f2d55840c..d4f130a9f5c8 100644
> --- a/include/linux/kvm_host.h
> +++ b/include/linux/kvm_host.h
> @@ -1442,7 +1442,7 @@ 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 a67e996cbf7f..a5bada53f1fe 100644
> --- a/virt/kvm/kvm_main.c
> +++ b/virt/kvm/kvm_main.c
> @@ -5697,22 +5697,14 @@ void kvm_unregister_perf_callbacks(void)
> }
> #endif
>
> -struct kvm_cpu_compat_check {
> - void *opaque;
> - int *ret;
> -};
> -
> -static void check_processor_compat(void *data)
> +static void check_processor_compat(void *rtn)
> {
> - struct kvm_cpu_compat_check *c = data;
> -
> - *c->ret = kvm_arch_check_processor_compat(c->opaque);
> + *(int *)rtn = 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;
>
> @@ -5740,10 +5732,8 @@ int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
> if (r < 0)
> goto out_free_1;
>
> - c.ret = &r;
> - c.opaque = opaque;
> for_each_online_cpu(cpu) {
> - smp_call_function_single(cpu, check_processor_compat, &c, 1);
> + smp_call_function_single(cpu, check_processor_compat, &r, 1);
> if (r < 0)
> goto out_free_2;
> }
