From: Maxim Levitsky <mlevitsk@redhat.com>
To: kvm@vger.kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>,
Yang Zhong <yang.zhong@intel.com>,
x86@kernel.org, Jim Mattson <jmattson@google.com>,
Vitaly Kuznetsov <vkuznets@redhat.com>,
Paolo Bonzini <pbonzini@redhat.com>,
Sean Christopherson <seanjc@google.com>,
Wanpeng Li <wanpengli@tencent.com>, Shuah Khan <shuah@kernel.org>,
Guang Zeng <guang.zeng@intel.com>, Joerg Roedel <joro@8bytes.org>,
Maxim Levitsky <mlevitsk@redhat.com>,
linux-kernel@vger.kernel.org,
Dave Hansen <dave.hansen@linux.intel.com>,
Ingo Molnar <mingo@redhat.com>,
linux-kselftest@vger.kernel.org,
Kees Cook <keescook@chromium.org>,
"H. Peter Anvin" <hpa@zytor.com>, Wei Wang <wei.w.wang@intel.com>,
Borislav Petkov <bp@alien8.de>
Subject: [PATCH RESEND v4 11/23] KVM: x86: emulator: introduce emulator_recalc_and_set_mode
Date: Tue, 25 Oct 2022 15:47:29 +0300 [thread overview]
Message-ID: <20221025124741.228045-12-mlevitsk@redhat.com> (raw)
In-Reply-To: <20221025124741.228045-1-mlevitsk@redhat.com>
Some instructions update the cpu execution mode, which needs to update the
emulation mode.
Extract this code, and make assign_eip_far use it.
assign_eip_far now reads CS, instead of getting it via a parameter,
which is ok, because callers always assign CS to the same value
before calling this function.
No functional change is intended.
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
---
arch/x86/kvm/emulate.c | 85 ++++++++++++++++++++++++++++--------------
1 file changed, 57 insertions(+), 28 deletions(-)
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index e23c984d6aae09..c65f57b6da9bf1 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -760,8 +760,7 @@ static int linearize(struct x86_emulate_ctxt *ctxt,
ctxt->mode, linear);
}
-static inline int assign_eip(struct x86_emulate_ctxt *ctxt, ulong dst,
- enum x86emul_mode mode)
+static inline int assign_eip(struct x86_emulate_ctxt *ctxt, ulong dst)
{
ulong linear;
int rc;
@@ -771,41 +770,71 @@ static inline int assign_eip(struct x86_emulate_ctxt *ctxt, ulong dst,
if (ctxt->op_bytes != sizeof(unsigned long))
addr.ea = dst & ((1UL << (ctxt->op_bytes << 3)) - 1);
- rc = __linearize(ctxt, addr, &max_size, 1, false, true, mode, &linear);
+ rc = __linearize(ctxt, addr, &max_size, 1, false, true, ctxt->mode, &linear);
if (rc == X86EMUL_CONTINUE)
ctxt->_eip = addr.ea;
return rc;
}
+static inline int emulator_recalc_and_set_mode(struct x86_emulate_ctxt *ctxt)
+{
+ u64 efer;
+ struct desc_struct cs;
+ u16 selector;
+ u32 base3;
+
+ ctxt->ops->get_msr(ctxt, MSR_EFER, &efer);
+
+ if (!(ctxt->ops->get_cr(ctxt, 0) & X86_CR0_PE)) {
+ /* Real mode. cpu must not have long mode active */
+ if (efer & EFER_LMA)
+ return X86EMUL_UNHANDLEABLE;
+ ctxt->mode = X86EMUL_MODE_REAL;
+ return X86EMUL_CONTINUE;
+ }
+
+ if (ctxt->eflags & X86_EFLAGS_VM) {
+ /* Protected/VM86 mode. cpu must not have long mode active */
+ if (efer & EFER_LMA)
+ return X86EMUL_UNHANDLEABLE;
+ ctxt->mode = X86EMUL_MODE_VM86;
+ return X86EMUL_CONTINUE;
+ }
+
+ if (!ctxt->ops->get_segment(ctxt, &selector, &cs, &base3, VCPU_SREG_CS))
+ return X86EMUL_UNHANDLEABLE;
+
+ if (efer & EFER_LMA) {
+ if (cs.l) {
+ /* Proper long mode */
+ ctxt->mode = X86EMUL_MODE_PROT64;
+ } else if (cs.d) {
+ /* 32 bit compatibility mode*/
+ ctxt->mode = X86EMUL_MODE_PROT32;
+ } else {
+ ctxt->mode = X86EMUL_MODE_PROT16;
+ }
+ } else {
+ /* Legacy 32 bit / 16 bit mode */
+ ctxt->mode = cs.d ? X86EMUL_MODE_PROT32 : X86EMUL_MODE_PROT16;
+ }
+
+ return X86EMUL_CONTINUE;
+}
+
static inline int assign_eip_near(struct x86_emulate_ctxt *ctxt, ulong dst)
{
- return assign_eip(ctxt, dst, ctxt->mode);
+ return assign_eip(ctxt, dst);
}
-static int assign_eip_far(struct x86_emulate_ctxt *ctxt, ulong dst,
- const struct desc_struct *cs_desc)
+static int assign_eip_far(struct x86_emulate_ctxt *ctxt, ulong dst)
{
- enum x86emul_mode mode = ctxt->mode;
- int rc;
+ int rc = emulator_recalc_and_set_mode(ctxt);
-#ifdef CONFIG_X86_64
- if (ctxt->mode >= X86EMUL_MODE_PROT16) {
- if (cs_desc->l) {
- u64 efer = 0;
+ if (rc != X86EMUL_CONTINUE)
+ return rc;
- ctxt->ops->get_msr(ctxt, MSR_EFER, &efer);
- if (efer & EFER_LMA)
- mode = X86EMUL_MODE_PROT64;
- } else
- mode = X86EMUL_MODE_PROT32; /* temporary value */
- }
-#endif
- if (mode == X86EMUL_MODE_PROT16 || mode == X86EMUL_MODE_PROT32)
- mode = cs_desc->d ? X86EMUL_MODE_PROT32 : X86EMUL_MODE_PROT16;
- rc = assign_eip(ctxt, dst, mode);
- if (rc == X86EMUL_CONTINUE)
- ctxt->mode = mode;
- return rc;
+ return assign_eip(ctxt, dst);
}
static inline int jmp_rel(struct x86_emulate_ctxt *ctxt, int rel)
@@ -2141,7 +2170,7 @@ static int em_jmp_far(struct x86_emulate_ctxt *ctxt)
if (rc != X86EMUL_CONTINUE)
return rc;
- rc = assign_eip_far(ctxt, ctxt->src.val, &new_desc);
+ rc = assign_eip_far(ctxt, ctxt->src.val);
/* Error handling is not implemented. */
if (rc != X86EMUL_CONTINUE)
return X86EMUL_UNHANDLEABLE;
@@ -2219,7 +2248,7 @@ static int em_ret_far(struct x86_emulate_ctxt *ctxt)
&new_desc);
if (rc != X86EMUL_CONTINUE)
return rc;
- rc = assign_eip_far(ctxt, eip, &new_desc);
+ rc = assign_eip_far(ctxt, eip);
/* Error handling is not implemented. */
if (rc != X86EMUL_CONTINUE)
return X86EMUL_UNHANDLEABLE;
@@ -3119,7 +3148,7 @@ static int em_call_far(struct x86_emulate_ctxt *ctxt)
if (rc != X86EMUL_CONTINUE)
return rc;
- rc = assign_eip_far(ctxt, ctxt->src.val, &new_desc);
+ rc = assign_eip_far(ctxt, ctxt->src.val);
if (rc != X86EMUL_CONTINUE)
goto fail;
--
2.34.3
next prev parent reply other threads:[~2022-10-25 12:52 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-10-25 12:47 [PATCH RESEND v4 00/23] SMM emulation and interrupt shadow fixes Maxim Levitsky
2022-10-25 12:47 ` [PATCH RESEND v4 01/23] KVM: x86: start moving SMM-related functions to new files Maxim Levitsky
2022-10-25 12:47 ` [PATCH RESEND v4 02/23] KVM: x86: move SMM entry to a new file Maxim Levitsky
2022-10-25 12:47 ` [PATCH RESEND v4 03/23] KVM: x86: move SMM exit " Maxim Levitsky
2022-10-25 12:47 ` [PATCH RESEND v4 04/23] KVM: x86: do not go through ctxt->ops when emulating rsm Maxim Levitsky
2022-10-25 12:47 ` [PATCH RESEND v4 05/23] KVM: allow compiling out SMM support Maxim Levitsky
2022-10-25 12:47 ` [PATCH RESEND v4 06/23] KVM: x86: compile out vendor-specific code if SMM is disabled Maxim Levitsky
2022-10-25 12:47 ` [PATCH RESEND v4 07/23] KVM: x86: remove SMRAM address space if SMM is not supported Maxim Levitsky
2022-10-25 12:47 ` [PATCH RESEND v4 08/23] KVM: x86: do not define KVM_REQ_SMI if SMM disabled Maxim Levitsky
2022-10-25 12:47 ` [PATCH RESEND v4 09/23] bug: introduce ASSERT_STRUCT_OFFSET Maxim Levitsky
2022-10-25 12:47 ` [PATCH RESEND v4 10/23] KVM: x86: emulator: em_sysexit should update ctxt->mode Maxim Levitsky
2022-10-25 12:47 ` Maxim Levitsky [this message]
2022-10-25 12:47 ` [PATCH RESEND v4 12/23] KVM: x86: emulator: update the emulation mode after rsm Maxim Levitsky
2022-10-25 12:47 ` [PATCH RESEND v4 13/23] KVM: x86: emulator: update the emulation mode after CR0 write Maxim Levitsky
2022-10-25 12:47 ` [PATCH RESEND v4 14/23] KVM: x86: smm: number of GPRs in the SMRAM image depends on the image format Maxim Levitsky
2022-10-25 12:47 ` [PATCH RESEND v4 15/23] KVM: x86: smm: check for failures on smm entry Maxim Levitsky
2022-10-25 12:47 ` [PATCH RESEND v4 16/23] KVM: x86: smm: add structs for KVM's smram layout Maxim Levitsky
2022-10-28 13:34 ` Paolo Bonzini
2022-10-25 12:47 ` [PATCH RESEND v4 17/23] KVM: x86: smm: use smram structs in the common code Maxim Levitsky
2022-10-25 12:47 ` [PATCH RESEND v4 18/23] KVM: x86: smm: use smram struct for 32 bit smram load/restore Maxim Levitsky
2022-10-25 12:47 ` [PATCH RESEND v4 19/23] KVM: x86: smm: use smram struct for 64 " Maxim Levitsky
2022-10-25 12:47 ` [PATCH RESEND v4 20/23] KVM: svm: drop explicit return value of kvm_vcpu_map Maxim Levitsky
2022-10-25 12:47 ` [PATCH RESEND v4 21/23] KVM: x86: SVM: use smram structs Maxim Levitsky
2022-10-25 12:47 ` [PATCH RESEND v4 22/23] KVM: x86: SVM: don't save SVM state to SMRAM when VM is not long mode capable Maxim Levitsky
2022-10-25 12:47 ` [PATCH RESEND v4 23/23] KVM: x86: smm: preserve interrupt shadow in SMRAM Maxim Levitsky
2022-10-28 10:35 ` Paolo Bonzini
2022-10-30 8:23 ` Maxim Levitsky
2022-10-27 16:49 ` [PATCH RESEND v4 00/23] SMM emulation and interrupt shadow fixes Paolo Bonzini
2022-10-27 17:06 ` Maxim Levitsky
2022-10-28 10:36 ` Paolo Bonzini
2022-10-28 22:42 ` Sean Christopherson
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=20221025124741.228045-12-mlevitsk@redhat.com \
--to=mlevitsk@redhat.com \
--cc=bp@alien8.de \
--cc=dave.hansen@linux.intel.com \
--cc=guang.zeng@intel.com \
--cc=hpa@zytor.com \
--cc=jmattson@google.com \
--cc=joro@8bytes.org \
--cc=keescook@chromium.org \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-kselftest@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=pbonzini@redhat.com \
--cc=seanjc@google.com \
--cc=shuah@kernel.org \
--cc=tglx@linutronix.de \
--cc=vkuznets@redhat.com \
--cc=wanpengli@tencent.com \
--cc=wei.w.wang@intel.com \
--cc=x86@kernel.org \
--cc=yang.zhong@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