From: Vitaly Kuznetsov <vkuznets@redhat.com>
To: linmiaohe <linmiaohe@huawei.com>
Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
x86@kernel.org, pbonzini@redhat.com, rkrcmar@redhat.com,
sean.j.christopherson@intel.com, wanpengli@tencent.com,
jmattson@google.com, joro@8bytes.org, tglx@linutronix.de,
mingo@redhat.com, bp@alien8.de, hpa@zytor.com
Subject: Re: [PATCH RESEND] KVM: X86: eliminate obsolete KVM_GET_CPUID2 ioctl
Date: Mon, 24 Feb 2020 11:06:45 +0100 [thread overview]
Message-ID: <87o8topadm.fsf@vitty.brq.redhat.com> (raw)
In-Reply-To: <1582516032-5161-1-git-send-email-linmiaohe@huawei.com>
linmiaohe <linmiaohe@huawei.com> writes:
> From: Miaohe Lin <linmiaohe@huawei.com>
>
> KVM_GET_CPUID2 ioctl is straight up broken
It may make sense to add the gory details from your previous patch where
you were trying to fix it.
> and not used anywhere. Remove it directly.
>
> Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
> Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
> ---
> arch/x86/kvm/cpuid.c | 20 --------------------
> arch/x86/kvm/cpuid.h | 3 ---
> arch/x86/kvm/x86.c | 17 -----------------
> include/uapi/linux/kvm.h | 1 -
> tools/include/uapi/linux/kvm.h | 1 -
> 5 files changed, 42 deletions(-)
>
> diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
> index b1c469446b07..5e041a1282b8 100644
> --- a/arch/x86/kvm/cpuid.c
> +++ b/arch/x86/kvm/cpuid.c
> @@ -261,26 +261,6 @@ int kvm_vcpu_ioctl_set_cpuid2(struct kvm_vcpu *vcpu,
> return r;
> }
>
> -int kvm_vcpu_ioctl_get_cpuid2(struct kvm_vcpu *vcpu,
> - struct kvm_cpuid2 *cpuid,
> - struct kvm_cpuid_entry2 __user *entries)
> -{
> - int r;
> -
> - r = -E2BIG;
> - if (cpuid->nent < vcpu->arch.cpuid_nent)
> - goto out;
> - r = -EFAULT;
> - if (copy_to_user(entries, &vcpu->arch.cpuid_entries,
> - vcpu->arch.cpuid_nent * sizeof(struct kvm_cpuid_entry2)))
> - goto out;
> - return 0;
> -
> -out:
> - cpuid->nent = vcpu->arch.cpuid_nent;
> - return r;
> -}
> -
> static __always_inline void cpuid_mask(u32 *word, int wordnum)
> {
> reverse_cpuid_check(wordnum);
> diff --git a/arch/x86/kvm/cpuid.h b/arch/x86/kvm/cpuid.h
> index 7366c618aa04..76555de38e1b 100644
> --- a/arch/x86/kvm/cpuid.h
> +++ b/arch/x86/kvm/cpuid.h
> @@ -19,9 +19,6 @@ int kvm_vcpu_ioctl_set_cpuid(struct kvm_vcpu *vcpu,
> int kvm_vcpu_ioctl_set_cpuid2(struct kvm_vcpu *vcpu,
> struct kvm_cpuid2 *cpuid,
> struct kvm_cpuid_entry2 __user *entries);
> -int kvm_vcpu_ioctl_get_cpuid2(struct kvm_vcpu *vcpu,
> - struct kvm_cpuid2 *cpuid,
> - struct kvm_cpuid_entry2 __user *entries);
> bool kvm_cpuid(struct kvm_vcpu *vcpu, u32 *eax, u32 *ebx,
> u32 *ecx, u32 *edx, bool check_limit);
>
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index fbabb2f06273..ddcc51b89e2c 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -4286,23 +4286,6 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
> cpuid_arg->entries);
> break;
> }
> - case KVM_GET_CPUID2: {
> - struct kvm_cpuid2 __user *cpuid_arg = argp;
> - struct kvm_cpuid2 cpuid;
> -
> - r = -EFAULT;
> - if (copy_from_user(&cpuid, cpuid_arg, sizeof(cpuid)))
> - goto out;
> - r = kvm_vcpu_ioctl_get_cpuid2(vcpu, &cpuid,
> - cpuid_arg->entries);
> - if (r)
> - goto out;
> - r = -EFAULT;
> - if (copy_to_user(cpuid_arg, &cpuid, sizeof(cpuid)))
> - goto out;
> - r = 0;
> - break;
> - }
> case KVM_GET_MSRS: {
> int idx = srcu_read_lock(&vcpu->kvm->srcu);
> r = msr_io(vcpu, argp, do_get_msr, 1);
> diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
> index 4b95f9a31a2f..b37b8c1f300e 100644
> --- a/include/uapi/linux/kvm.h
> +++ b/include/uapi/linux/kvm.h
> @@ -1380,7 +1380,6 @@ struct kvm_s390_ucas_mapping {
> #define KVM_GET_LAPIC _IOR(KVMIO, 0x8e, struct kvm_lapic_state)
> #define KVM_SET_LAPIC _IOW(KVMIO, 0x8f, struct kvm_lapic_state)
> #define KVM_SET_CPUID2 _IOW(KVMIO, 0x90, struct kvm_cpuid2)
> -#define KVM_GET_CPUID2 _IOWR(KVMIO, 0x91, struct kvm_cpuid2)
Even if we decide to be strong and remove KVM_GET_CPUID2 completely, I'd
suggest we leave a comment here saying that it was deprecated. Leaving
the branch in case (returning the same -EINVAL as passing an unsupported
IOCTL) may also make sense (with a 'deprecated' comment of course).
> /* Available with KVM_CAP_VAPIC */
> #define KVM_TPR_ACCESS_REPORTING _IOWR(KVMIO, 0x92, struct kvm_tpr_access_ctl)
> /* Available with KVM_CAP_VAPIC */
> diff --git a/tools/include/uapi/linux/kvm.h b/tools/include/uapi/linux/kvm.h
> index f0a16b4adbbd..431106dedd2c 100644
> --- a/tools/include/uapi/linux/kvm.h
> +++ b/tools/include/uapi/linux/kvm.h
> @@ -1379,7 +1379,6 @@ struct kvm_s390_ucas_mapping {
> #define KVM_GET_LAPIC _IOR(KVMIO, 0x8e, struct kvm_lapic_state)
> #define KVM_SET_LAPIC _IOW(KVMIO, 0x8f, struct kvm_lapic_state)
> #define KVM_SET_CPUID2 _IOW(KVMIO, 0x90, struct kvm_cpuid2)
> -#define KVM_GET_CPUID2 _IOWR(KVMIO, 0x91, struct kvm_cpuid2)
> /* Available with KVM_CAP_VAPIC */
> #define KVM_TPR_ACCESS_REPORTING _IOWR(KVMIO, 0x92, struct kvm_tpr_access_ctl)
> /* Available with KVM_CAP_VAPIC */
--
Vitaly
next prev parent reply other threads:[~2020-02-24 10:06 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-24 3:47 [PATCH RESEND] KVM: X86: eliminate obsolete KVM_GET_CPUID2 ioctl linmiaohe
2020-02-24 10:06 ` Vitaly Kuznetsov [this message]
2020-02-25 1:38 linmiaohe
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=87o8topadm.fsf@vitty.brq.redhat.com \
--to=vkuznets@redhat.com \
--cc=bp@alien8.de \
--cc=hpa@zytor.com \
--cc=jmattson@google.com \
--cc=joro@8bytes.org \
--cc=kvm@vger.kernel.org \
--cc=linmiaohe@huawei.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=pbonzini@redhat.com \
--cc=rkrcmar@redhat.com \
--cc=sean.j.christopherson@intel.com \
--cc=tglx@linutronix.de \
--cc=wanpengli@tencent.com \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).