From: Gleb Natapov <gleb@redhat.com>
To: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Avi Kivity <avi.kivity@gmail.com>, kvm <kvm@vger.kernel.org>
Subject: Re: KVM: VMX: fix incorrect cached cpl value with real/v8086 modes (v3)
Date: Tue, 8 Jan 2013 12:56:53 +0200 [thread overview]
Message-ID: <20130108105653.GK21250@redhat.com> (raw)
In-Reply-To: <20130107212706.GB26134@amt.cnet>
On Mon, Jan 07, 2013 at 07:27:06PM -0200, Marcelo Tosatti wrote:
>
> CPL is always 0 when in real mode, and always 3 when virtual 8086 mode.
>
> Using values other than those can cause failures on operations that
> check CPL.
>
> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
>
Reviewed-by: Gleb Natapov <gleb@redhat.com>
> diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
> index 55dfc37..dd2a85c 100644
> --- a/arch/x86/kvm/vmx.c
> +++ b/arch/x86/kvm/vmx.c
> @@ -1696,7 +1696,6 @@ static unsigned long vmx_get_rflags(struct kvm_vcpu *vcpu)
> static void vmx_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags)
> {
> __set_bit(VCPU_EXREG_RFLAGS, (ulong *)&vcpu->arch.regs_avail);
> - __clear_bit(VCPU_EXREG_CPL, (ulong *)&vcpu->arch.regs_avail);
> to_vmx(vcpu)->rflags = rflags;
> if (to_vmx(vcpu)->rmode.vm86_active) {
> to_vmx(vcpu)->rmode.save_rflags = rflags;
> @@ -3110,7 +3109,6 @@ static void vmx_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0)
> vmcs_writel(CR0_READ_SHADOW, cr0);
> vmcs_writel(GUEST_CR0, hw_cr0);
> vcpu->arch.cr0 = cr0;
> - __clear_bit(VCPU_EXREG_CPL, (ulong *)&vcpu->arch.regs_avail);
> }
>
> static u64 construct_eptp(unsigned long root_hpa)
> @@ -3220,8 +3218,10 @@ static u64 vmx_get_segment_base(struct kvm_vcpu *vcpu, int seg)
> return vmx_read_guest_seg_base(to_vmx(vcpu), seg);
> }
>
> -static int __vmx_get_cpl(struct kvm_vcpu *vcpu)
> +static int vmx_get_cpl(struct kvm_vcpu *vcpu)
> {
> + struct vcpu_vmx *vmx = to_vmx(vcpu);
> +
> if (!is_protmode(vcpu))
> return 0;
>
> @@ -3229,13 +3229,6 @@ static int __vmx_get_cpl(struct kvm_vcpu *vcpu)
> && (kvm_get_rflags(vcpu) & X86_EFLAGS_VM)) /* if virtual 8086 */
> return 3;
>
> - return vmx_read_guest_seg_selector(to_vmx(vcpu), VCPU_SREG_CS) & 3;
> -}
> -
> -static int vmx_get_cpl(struct kvm_vcpu *vcpu)
> -{
> - struct vcpu_vmx *vmx = to_vmx(vcpu);
> -
> /*
> * If we enter real mode with cs.sel & 3 != 0, the normal CPL calculations
> * fail; use the cache instead.
> @@ -3246,7 +3239,7 @@ static int vmx_get_cpl(struct kvm_vcpu *vcpu)
>
> if (!test_bit(VCPU_EXREG_CPL, (ulong *)&vcpu->arch.regs_avail)) {
> __set_bit(VCPU_EXREG_CPL, (ulong *)&vcpu->arch.regs_avail);
> - vmx->cpl = __vmx_get_cpl(vcpu);
> + vmx->cpl = vmx_read_guest_seg_selector(vmx, VCPU_SREG_CS) & 3;
> }
>
> return vmx->cpl;
--
Gleb.
prev parent reply other threads:[~2013-01-08 10:56 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-12-19 13:29 KVM: VMX: fix incorrect cached cpl value with real/v8086 modes Marcelo Tosatti
[not found] ` <CAEbWair0awmpB9QXFGXJmooSsHg3B6P3uZrmLcyzs=T70TS7VA@mail.gmail.com>
2012-12-25 12:48 ` Gleb Natapov
2012-12-25 21:37 ` Marcelo Tosatti
2012-12-26 5:25 ` Gleb Natapov
2012-12-26 13:25 ` Marcelo Tosatti
2012-12-26 13:33 ` Gleb Natapov
2013-01-01 23:36 ` Marcelo Tosatti
2013-01-03 8:11 ` Gleb Natapov
2013-01-03 13:19 ` Marcelo Tosatti
2013-01-04 11:16 ` Gleb Natapov
2013-01-01 23:41 ` Marcelo Tosatti
2013-01-03 13:49 ` KVM: VMX: fix incorrect cached cpl value with real/v8086 modes (v2) Marcelo Tosatti
2013-01-07 21:27 ` KVM: VMX: fix incorrect cached cpl value with real/v8086 modes (v3) Marcelo Tosatti
2013-01-08 10:56 ` Gleb Natapov [this message]
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=20130108105653.GK21250@redhat.com \
--to=gleb@redhat.com \
--cc=avi.kivity@gmail.com \
--cc=kvm@vger.kernel.org \
--cc=mtosatti@redhat.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.