kvm.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Yang Weijiang <weijiang.yang@intel.com>
To: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Yang Weijiang <weijiang.yang@intel.com>,
	kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
	pbonzini@redhat.com, mst@redhat.com, rkrcmar@redhat.com,
	jmattson@google.com
Subject: Re: [PATCH v6 2/8] KVM: x86: Add a helper function for CPUID(0xD,n>=1) enumeration
Date: Tue, 13 Aug 2019 14:11:22 +0800	[thread overview]
Message-ID: <20190813061121.GF2432@local-michael-cet-test> (raw)
In-Reply-To: <20190812221811.GB4996@linux.intel.com>

On Mon, Aug 12, 2019 at 03:18:11PM -0700, Sean Christopherson wrote:
> On Thu, Jul 25, 2019 at 11:12:40AM +0800, Yang Weijiang wrote:
> > To make the code look clean, wrap CPUID(0xD,n>=1) enumeration
> > code in a helper function now.
> > 
> > Signed-off-by: Yang Weijiang <weijiang.yang@intel.com>
> > ---
> >  arch/x86/kvm/cpuid.c | 44 ++++++++++++++++++++++++++++++++++++++++++++
> >  1 file changed, 44 insertions(+)
> > 
> > diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
> > index 4992e7c99588..29cbde7538a3 100644
> > --- a/arch/x86/kvm/cpuid.c
> > +++ b/arch/x86/kvm/cpuid.c
> > @@ -313,6 +313,50 @@ static int __do_cpuid_ent_emulated(struct kvm_cpuid_entry2 *entry,
> >  	return 0;
> >  }
> >  
> > +static inline int __do_cpuid_dx_leaf(struct kvm_cpuid_entry2 *entry, int *nent,
> 
> 'dx' makes me think of the generic reference to RDX vs EDX.  Maybe
> __do_cpuid_0xd_leaf()?
>
OK, will change it.
> > +				     int maxnent, u64 xss_mask, u64 xcr0_mask,
> > +				     u32 eax_mask)
> > +{
> > +	int idx, i;
> > +	u64 mask;
> > +	u64 supported;
> > +
> > +	for (idx = 1, i = 1; idx < 64; ++idx) {
> 
> Rather than loop here, I think it makes sense to loop in the caller to
> make the code consistent with do_cpuid_7_mask() added by commit
> 
>   54d360d41211 ("KVM: cpuid: extract do_cpuid_7_mask and support multiple subleafs")
> 
OK, will follow the patch to modify the helper.

> > +		mask = ((u64)1 << idx);
> > +		if (*nent >= maxnent)
> > +			return -EINVAL;
> > +
> > +		do_cpuid_1_ent(&entry[i], 0xD, idx);
> > +		if (idx == 1) {
> > +			entry[i].eax &= eax_mask;
> > +			cpuid_mask(&entry[i].eax, CPUID_D_1_EAX);
> > +			supported = xcr0_mask | xss_mask;
> > +			entry[i].ebx = 0;
> > +			entry[i].edx = 0;
> > +			entry[i].ecx &= xss_mask;
> > +			if (entry[i].eax & (F(XSAVES) | F(XSAVEC))) {
> > +				entry[i].ebx =
> > +					xstate_required_size(supported,
> > +							     true);
> > +			}
> > +		} else {
> > +			supported = (entry[i].ecx & 1) ? xss_mask :
> > +				     xcr0_mask;
> > +			if (entry[i].eax == 0 || !(supported & mask))
> > +				continue;
> > +			entry[i].ecx &= 1;
> > +			entry[i].edx = 0;
> > +			if (entry[i].ecx)
> > +				entry[i].ebx = 0;
> > +		}
> > +		entry[i].flags |=
> > +			KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
> > +		++*nent;
> > +		++i;
> > +	}
> > +	return 0;
> > +}
> > +
> 
> Extracting code into a helper should be done in the same patch that the
> existing code is replaced with a call to the helper, i.e. the chunk of the
> next patch that invokes the helper should be squashed with this patch.
>
OK, will squash this patch in next release.

> >  static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
> >  				 u32 index, int *nent, int maxnent)
> >  {
> > -- 
> > 2.17.2
> > 

  reply	other threads:[~2019-08-13  6:10 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-07-25  3:12 [PATCH v6 0/8] Introduce support for Guest CET feature Yang Weijiang
2019-07-25  3:12 ` [PATCH v6 1/8] KVM: VMX: Define CET VMCS fields and control bits Yang Weijiang
2019-07-25  3:12 ` [PATCH v6 2/8] KVM: x86: Add a helper function for CPUID(0xD,n>=1) enumeration Yang Weijiang
2019-08-12 22:18   ` Sean Christopherson
2019-08-13  6:11     ` Yang Weijiang [this message]
2019-07-25  3:12 ` [PATCH v6 3/8] KVM: x86: Implement CET CPUID enumeration for Guest Yang Weijiang
2019-08-13  0:06   ` Sean Christopherson
2019-08-13  5:27     ` Yang Weijiang
2019-07-25  3:12 ` [PATCH v6 4/8] KVM: VMX: Pass through CET related MSRs to Guest Yang Weijiang
2019-08-12 23:53   ` Sean Christopherson
2019-08-13  5:49     ` Yang Weijiang
2019-07-25  3:12 ` [PATCH v6 5/8] KVM: VMX: Load Guest CET via VMCS when CET is enabled in Guest Yang Weijiang
2019-08-12 23:56   ` Sean Christopherson
2019-08-13  5:38     ` Yang Weijiang
2019-07-25  3:12 ` [PATCH v6 6/8] KVM: x86: Add CET bits setting in CR4 and XSS Yang Weijiang
2019-07-25  3:12 ` [PATCH v6 7/8] KVM: x86: Load Guest fpu state when accessing MSRs managed by XSAVES Yang Weijiang
2019-08-12 23:02   ` Sean Christopherson
2019-08-12 23:04     ` Sean Christopherson
2019-08-12 23:29     ` Sean Christopherson
2019-08-13  6:06       ` Yang Weijiang
2019-08-13  6:05     ` Yang Weijiang
2019-07-25  3:12 ` [PATCH v6 8/8] KVM: x86: Add user-space access interface for CET MSRs Yang Weijiang
2019-08-12 23:43   ` Sean Christopherson
2019-08-13  5:41     ` Yang Weijiang

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=20190813061121.GF2432@local-michael-cet-test \
    --to=weijiang.yang@intel.com \
    --cc=jmattson@google.com \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mst@redhat.com \
    --cc=pbonzini@redhat.com \
    --cc=rkrcmar@redhat.com \
    --cc=sean.j.christopherson@intel.com \
    /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).