linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Vitaly Kuznetsov <vkuznets@redhat.com>
To: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org,
	"Paolo Bonzini" <pbonzini@redhat.com>,
	"Radim Krčmář" <rkrcmar@redhat.com>,
	"Joerg Roedel" <joro@8bytes.org>,
	"Jim Mattson" <jmattson@google.com>
Subject: [PATCH 4/5] x86: KVM: add xsetbv to the emulator
Date: Thu,  1 Aug 2019 07:14:17 +0200	[thread overview]
Message-ID: <20190801051418.15905-5-vkuznets@redhat.com> (raw)
In-Reply-To: <20190801051418.15905-1-vkuznets@redhat.com>

To avoid hardcoding xsetbv length to '3' we need to support decoding it in
the emulator.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
---
 arch/x86/include/asm/kvm_emulate.h |  3 ++-
 arch/x86/kvm/emulate.c             | 23 ++++++++++++++++++++++-
 arch/x86/kvm/svm.c                 |  1 +
 arch/x86/kvm/x86.c                 |  6 ++++++
 4 files changed, 31 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/kvm_emulate.h b/arch/x86/include/asm/kvm_emulate.h
index feab24cac610..77cf6c11f66b 100644
--- a/arch/x86/include/asm/kvm_emulate.h
+++ b/arch/x86/include/asm/kvm_emulate.h
@@ -229,7 +229,7 @@ struct x86_emulate_ops {
 	int (*pre_leave_smm)(struct x86_emulate_ctxt *ctxt,
 			     const char *smstate);
 	void (*post_leave_smm)(struct x86_emulate_ctxt *ctxt);
-
+	int (*set_xcr)(struct x86_emulate_ctxt *ctxt, u32 index, u64 xcr);
 };
 
 typedef u32 __attribute__((vector_size(16))) sse128_t;
@@ -429,6 +429,7 @@ enum x86_intercept {
 	x86_intercept_ins,
 	x86_intercept_out,
 	x86_intercept_outs,
+	x86_intercept_xsetbv,
 
 	nr_x86_intercepts
 };
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 718f7d9afedc..f9e843dd992a 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -4156,6 +4156,20 @@ static int em_fxrstor(struct x86_emulate_ctxt *ctxt)
 	return rc;
 }
 
+static int em_xsetbv(struct x86_emulate_ctxt *ctxt)
+{
+	u32 eax, ecx, edx;
+
+	eax = reg_read(ctxt, VCPU_REGS_RAX);
+	edx = reg_read(ctxt, VCPU_REGS_RDX);
+	ecx = reg_read(ctxt, VCPU_REGS_RCX);
+
+	if (ctxt->ops->set_xcr(ctxt, ecx, ((u64)edx << 32) | eax))
+		return emulate_gp(ctxt, 0);
+
+	return X86EMUL_CONTINUE;
+}
+
 static bool valid_cr(int nr)
 {
 	switch (nr) {
@@ -4409,6 +4423,12 @@ static const struct opcode group7_rm1[] = {
 	N, N, N, N, N, N,
 };
 
+static const struct opcode group7_rm2[] = {
+	N,
+	II(ImplicitOps | Priv,			em_xsetbv,	xsetbv),
+	N, N, N, N, N, N,
+};
+
 static const struct opcode group7_rm3[] = {
 	DIP(SrcNone | Prot | Priv,		vmrun,		check_svme_pa),
 	II(SrcNone  | Prot | EmulateOnUD,	em_hypercall,	vmmcall),
@@ -4498,7 +4518,8 @@ static const struct group_dual group7 = { {
 }, {
 	EXT(0, group7_rm0),
 	EXT(0, group7_rm1),
-	N, EXT(0, group7_rm3),
+	EXT(0, group7_rm2),
+	EXT(0, group7_rm3),
 	II(SrcNone | DstMem | Mov,		em_smsw, smsw), N,
 	II(SrcMem16 | Mov | Priv,		em_lmsw, lmsw),
 	EXT(0, group7_rm7),
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 7c7dff3f461f..f0e7e1b1c017 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -6066,6 +6066,7 @@ static const struct __x86_intercept {
 	[x86_intercept_ins]		= POST_EX(SVM_EXIT_IOIO),
 	[x86_intercept_out]		= POST_EX(SVM_EXIT_IOIO),
 	[x86_intercept_outs]		= POST_EX(SVM_EXIT_IOIO),
+	[x86_intercept_xsetbv]		= PRE_EX(SVM_EXIT_XSETBV),
 };
 
 #undef PRE_EX
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index c6d951cbd76c..9512cc38dfe9 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6068,6 +6068,11 @@ static void emulator_post_leave_smm(struct x86_emulate_ctxt *ctxt)
 	kvm_smm_changed(emul_to_vcpu(ctxt));
 }
 
+static int emulator_set_xcr(struct x86_emulate_ctxt *ctxt, u32 index, u64 xcr)
+{
+	return __kvm_set_xcr(emul_to_vcpu(ctxt), index, xcr);
+}
+
 static const struct x86_emulate_ops emulate_ops = {
 	.read_gpr            = emulator_read_gpr,
 	.write_gpr           = emulator_write_gpr,
@@ -6109,6 +6114,7 @@ static const struct x86_emulate_ops emulate_ops = {
 	.set_hflags          = emulator_set_hflags,
 	.pre_leave_smm       = emulator_pre_leave_smm,
 	.post_leave_smm      = emulator_post_leave_smm,
+	.set_xcr             = emulator_set_xcr,
 };
 
 static void toggle_interruptibility(struct kvm_vcpu *vcpu, u32 mask)
-- 
2.20.1


  parent reply	other threads:[~2019-08-01  5:14 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-08-01  5:14 [PATCH 0/5] x86: KVM: svm: get rid of hardcoded instructions lengths Vitaly Kuznetsov
2019-08-01  5:14 ` [PATCH 1/5] x86: KVM: svm: don't pretend to advance RIP in case wrmsr_interception() results in #GP Vitaly Kuznetsov
2019-08-01  5:14 ` [PATCH 2/5] x86: KVM: svm: avoid flooding logs when skip_emulated_instruction() fails Vitaly Kuznetsov
2019-08-01  5:14 ` [PATCH 3/5] x86: KVM: svm: clear interrupt shadow on all paths in skip_emulated_instruction() Vitaly Kuznetsov
2019-08-01 14:18   ` Sean Christopherson
2019-08-01 14:43     ` Vitaly Kuznetsov
2019-08-01  5:14 ` Vitaly Kuznetsov [this message]
2019-08-01  5:14 ` [PATCH 5/5] x86: KVM: svm: remove hardcoded instruction length from intercepts Vitaly Kuznetsov

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=20190801051418.15905-5-vkuznets@redhat.com \
    --to=vkuznets@redhat.com \
    --cc=jmattson@google.com \
    --cc=joro@8bytes.org \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=pbonzini@redhat.com \
    --cc=rkrcmar@redhat.com \
    --subject='Re: [PATCH 4/5] x86: KVM: add xsetbv to the emulator' \
    /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

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).