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backport "SMM emulation and interrupt shadow fixes"

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Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
This commit is contained in:
Thomas Lamprecht 2022-07-27 13:45:07 +02:00
parent aa04318f19
commit f6df304f26
10 changed files with 1387 additions and 0 deletions
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31
patches/kernel/0015-KVM-x86-emulator-em_sysexit-should-update-ctxt-mode.patch Normal file
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@ -0,0 +1,31 @@
From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Maxim Levitsky <mlevitsk@redhat.com>
Date: Tue, 21 Jun 2022 18:08:52 +0300
Subject: [PATCH] KVM: x86: emulator: em_sysexit should update ctxt->mode
This is one of the instructions that can change the
processor mode.
Note that this is likely a benign bug, because the only problematic
mode change is from 32 bit to 64 bit which can lead to truncation of RIP,
and it is not possible to do with sysexit,
since sysexit running in 32 bit mode will be limited to 32 bit version.
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
---
arch/x86/kvm/emulate.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 318a78379ca6..35b12692739c 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -2862,6 +2862,7 @@ static int em_sysexit(struct x86_emulate_ctxt *ctxt)
ops->set_segment(ctxt, ss_sel, &ss, 0, VCPU_SREG_SS);
ctxt->_eip = rdx;
+ ctxt->mode = usermode;
*reg_write(ctxt, VCPU_REGS_RSP) = rcx;
return X86EMUL_CONTINUE;

158
patches/kernel/0016-KVM-x86-emulator-introduce-update_emulation_mode.patch Normal file
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@ -0,0 +1,158 @@
From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Maxim Levitsky <mlevitsk@redhat.com>
Date: Tue, 21 Jun 2022 18:08:53 +0300
Subject: [PATCH] KVM: x86: emulator: introduce update_emulation_mode
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 it.
No functional change is intended.
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.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 35b12692739c..1b5123a882a1 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -795,8 +795,7 @@ 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;
@@ -806,41 +805,71 @@ 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 update_emulation_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 = update_emulation_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)
@@ -2154,7 +2183,7 @@ 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;
@@ -2235,7 +2264,7 @@ 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;
@@ -3459,7 +3488,7 @@ 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;

127
patches/kernel/0017-KVM-x86-emulator-remove-assign_eip_near-far.patch Normal file
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@ -0,0 +1,127 @@
From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Maxim Levitsky <mlevitsk@redhat.com>
Date: Tue, 21 Jun 2022 18:08:54 +0300
Subject: [PATCH] KVM: x86: emulator: remove assign_eip_near/far
Now the assign_eip_far just updates the emulation mode in addition to
updating the rip, it doesn't make sense to keep that function.
Move mode update to the callers and remove these functions.
No functional change is intended.
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
---
arch/x86/kvm/emulate.c | 47 +++++++++++++++++++++---------------------
1 file changed, 24 insertions(+), 23 deletions(-)
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 1b5123a882a1..9e305e0cd815 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -857,24 +857,9 @@ static inline int update_emulation_mode(struct x86_emulate_ctxt *ctxt)
return X86EMUL_CONTINUE;
}
-static inline int assign_eip_near(struct x86_emulate_ctxt *ctxt, ulong dst)
-{
- return assign_eip(ctxt, dst);
-}
-
-static int assign_eip_far(struct x86_emulate_ctxt *ctxt, ulong dst)
-{
- int rc = update_emulation_mode(ctxt);
-
- if (rc != X86EMUL_CONTINUE)
- return rc;
-
- return assign_eip(ctxt, dst);
-}
-
static inline int jmp_rel(struct x86_emulate_ctxt *ctxt, int rel)
{
- return assign_eip_near(ctxt, ctxt->_eip + rel);
+ return assign_eip(ctxt, ctxt->_eip + rel);
}
static int linear_read_system(struct x86_emulate_ctxt *ctxt, ulong linear,
@@ -2183,7 +2168,12 @@ static int em_jmp_far(struct x86_emulate_ctxt *ctxt)
if (rc != X86EMUL_CONTINUE)
return rc;
- rc = assign_eip_far(ctxt, ctxt->src.val);
+ rc = update_emulation_mode(ctxt);
+ if (rc != X86EMUL_CONTINUE)
+ return rc;
+
+ rc = assign_eip(ctxt, ctxt->src.val);
+
/* Error handling is not implemented. */
if (rc != X86EMUL_CONTINUE)
return X86EMUL_UNHANDLEABLE;
@@ -2193,7 +2183,7 @@ static int em_jmp_far(struct x86_emulate_ctxt *ctxt)
static int em_jmp_abs(struct x86_emulate_ctxt *ctxt)
{
- return assign_eip_near(ctxt, ctxt->src.val);
+ return assign_eip(ctxt, ctxt->src.val);
}
static int em_call_near_abs(struct x86_emulate_ctxt *ctxt)
@@ -2202,7 +2192,7 @@ static int em_call_near_abs(struct x86_emulate_ctxt *ctxt)
long int old_eip;
old_eip = ctxt->_eip;
- rc = assign_eip_near(ctxt, ctxt->src.val);
+ rc = assign_eip(ctxt, ctxt->src.val);
if (rc != X86EMUL_CONTINUE)
return rc;
ctxt->src.val = old_eip;
@@ -2240,7 +2230,7 @@ static int em_ret(struct x86_emulate_ctxt *ctxt)
if (rc != X86EMUL_CONTINUE)
return rc;
- return assign_eip_near(ctxt, eip);
+ return assign_eip(ctxt, eip);
}
static int em_ret_far(struct x86_emulate_ctxt *ctxt)
@@ -2264,7 +2254,13 @@ static int em_ret_far(struct x86_emulate_ctxt *ctxt)
&new_desc);
if (rc != X86EMUL_CONTINUE)
return rc;
- rc = assign_eip_far(ctxt, eip);
+
+ rc = update_emulation_mode(ctxt);
+ if (rc != X86EMUL_CONTINUE)
+ return rc;
+
+ rc = assign_eip(ctxt, eip);
+
/* Error handling is not implemented. */
if (rc != X86EMUL_CONTINUE)
return X86EMUL_UNHANDLEABLE;
@@ -3488,7 +3484,12 @@ static int em_call_far(struct x86_emulate_ctxt *ctxt)
if (rc != X86EMUL_CONTINUE)
return rc;
- rc = assign_eip_far(ctxt, ctxt->src.val);
+ rc = update_emulation_mode(ctxt);
+ if (rc != X86EMUL_CONTINUE)
+ return rc;
+
+ rc = assign_eip(ctxt, ctxt->src.val);
+
if (rc != X86EMUL_CONTINUE)
goto fail;
@@ -3521,7 +3522,7 @@ static int em_ret_near_imm(struct x86_emulate_ctxt *ctxt)
rc = emulate_pop(ctxt, &eip, ctxt->op_bytes);
if (rc != X86EMUL_CONTINUE)
return rc;
- rc = assign_eip_near(ctxt, eip);
+ rc = assign_eip(ctxt, eip);
if (rc != X86EMUL_CONTINUE)
return rc;
rsp_increment(ctxt, ctxt->src.val);

34
patches/kernel/0018-KVM-x86-emulator-update-the-emulation-mode-after-rsm.patch Normal file
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@ -0,0 +1,34 @@
From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Maxim Levitsky <mlevitsk@redhat.com>
Date: Tue, 21 Jun 2022 18:08:55 +0300
Subject: [PATCH] KVM: x86: emulator: update the emulation mode after rsm
This ensures that RIP will be correctly written back,
because the RSM instruction can switch the CPU mode from
32 bit (or less) to 64 bit.
This fixes a guest crash in case the #SMI is received
while the guest runs a code from an address > 32 bit.
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
---
arch/x86/kvm/emulate.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 9e305e0cd815..c582639ea2b4 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -2635,6 +2635,11 @@ static int em_rsm(struct x86_emulate_ctxt *ctxt)
if (ret != X86EMUL_CONTINUE)
goto emulate_shutdown;
+
+ ret = update_emulation_mode(ctxt);
+ if (ret != X86EMUL_CONTINUE)
+ goto emulate_shutdown;
+
/*
* Note, the ctxt->ops callbacks are responsible for handling side
* effects when writing MSRs and CRs, e.g. MMU context resets, CPUID

46
patches/kernel/0019-KVM-x86-emulator-update-the-emulation-mode-after-CR0.patch Normal file
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@ -0,0 +1,46 @@
From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Maxim Levitsky <mlevitsk@redhat.com>
Date: Tue, 21 Jun 2022 18:08:56 +0300
Subject: [PATCH] KVM: x86: emulator: update the emulation mode after CR0 write
CR0.PE toggles real/protected mode, thus its update
should update the emulation mode.
This is likely a benign bug because there is no writeback
of state, other than the RIP increment, and when toggling
CR0.PE, the CPU has to execute code from a very low memory address.
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
---
arch/x86/kvm/emulate.c | 13 ++++++++++++-
1 file changed, 12 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index c582639ea2b4..38d9bfa650ec 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -3636,11 +3636,22 @@ static int em_movbe(struct x86_emulate_ctxt *ctxt)
static int em_cr_write(struct x86_emulate_ctxt *ctxt)
{
- if (ctxt->ops->set_cr(ctxt, ctxt->modrm_reg, ctxt->src.val))
+ int cr_num = ctxt->modrm_reg;
+ int r;
+
+ if (ctxt->ops->set_cr(ctxt, cr_num, ctxt->src.val))
return emulate_gp(ctxt, 0);
/* Disable writeback. */
ctxt->dst.type = OP_NONE;
+
+ if (cr_num == 0) {
+ /* CR0 write might have updated CR0.PE */
+ r = update_emulation_mode(ctxt);
+ if (r != X86EMUL_CONTINUE)
+ return r;
+ }
+
return X86EMUL_CONTINUE;
}

166
patches/kernel/0020-KVM-x86-emulator-smm-add-structs-for-KVM-s-smram-lay.patch Normal file
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@ -0,0 +1,166 @@
From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Maxim Levitsky <mlevitsk@redhat.com>
Date: Tue, 21 Jun 2022 18:08:58 +0300
Subject: [PATCH] KVM: x86: emulator/smm: add structs for KVM's smram layout
Those structs will be used to read/write the smram state image.
Also document the differences between KVM's SMRAM layout and SMRAM
layout that is used by real Intel/AMD cpus.
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
---
arch/x86/kvm/kvm_emulate.h | 139 +++++++++++++++++++++++++++++++++++++
1 file changed, 139 insertions(+)
diff --git a/arch/x86/kvm/kvm_emulate.h b/arch/x86/kvm/kvm_emulate.h
index fb09cd22cb7f..d16b377be70b 100644
--- a/arch/x86/kvm/kvm_emulate.h
+++ b/arch/x86/kvm/kvm_emulate.h
@@ -482,6 +482,145 @@ enum x86_intercept {
nr_x86_intercepts
};
+
+/*
+ * 32 bit KVM's emulated SMM layout
+ * Loosely based on Intel's layout
+ */
+
+struct kvm_smm_seg_state_32 {
+ u32 flags;
+ u32 limit;
+ u32 base;
+} __packed;
+
+struct kvm_smram_state_32 {
+
+ u32 reserved1[62]; /* FE00 - FEF7 */
+ u32 smbase; /* FEF8 */
+ u32 smm_revision; /* FEFC */
+ u32 reserved2[5]; /* FF00-FF13 */
+ /* CR4 is not present in Intel/AMD SMRAM image*/
+ u32 cr4; /* FF14 */
+ u32 reserved3[5]; /* FF18 */
+
+ /*
+ * Segment state is not present/documented in the
+ * Intel/AMD SMRAM image
+ */
+ struct kvm_smm_seg_state_32 ds; /* FF2C */
+ struct kvm_smm_seg_state_32 fs; /* FF38 */
+ struct kvm_smm_seg_state_32 gs; /* FF44 */
+ /* idtr has only base and limit*/
+ struct kvm_smm_seg_state_32 idtr; /* FF50 */
+ struct kvm_smm_seg_state_32 tr; /* FF5C */
+ u32 reserved; /* FF68 */
+ /* gdtr has only base and limit*/
+ struct kvm_smm_seg_state_32 gdtr; /* FF6C */
+ struct kvm_smm_seg_state_32 ldtr; /* FF78 */
+ struct kvm_smm_seg_state_32 es; /* FF84 */
+ struct kvm_smm_seg_state_32 cs; /* FF90 */
+ struct kvm_smm_seg_state_32 ss; /* FF9C */
+
+ u32 es_sel; /* FFA8 */
+ u32 cs_sel; /* FFAC */
+ u32 ss_sel; /* FFB0 */
+ u32 ds_sel; /* FFB4 */
+ u32 fs_sel; /* FFB8 */
+ u32 gs_sel; /* FFBC */
+ u32 ldtr_sel; /* FFC0 */
+ u32 tr_sel; /* FFC4 */
+
+ u32 dr7; /* FFC8 */
+ u32 dr6; /* FFCC */
+
+ /* GPRS in the "natural" X86 order (RAX/RCX/RDX.../RDI)*/
+ u32 gprs[8]; /* FFD0-FFEC */
+
+ u32 eip; /* FFF0 */
+ u32 eflags; /* FFF4 */
+ u32 cr3; /* FFF8 */
+ u32 cr0; /* FFFC */
+} __packed;
+
+/*
+ * 64 bit KVM's emulated SMM layout
+ * Based on AMD64 layout
+ */
+
+struct kvm_smm_seg_state_64 {
+ u16 selector;
+ u16 attributes;
+ u32 limit;
+ u64 base;
+};
+
+struct kvm_smram_state_64 {
+ struct kvm_smm_seg_state_64 es; /* FE00 (R/O) */
+ struct kvm_smm_seg_state_64 cs; /* FE10 (R/O) */
+ struct kvm_smm_seg_state_64 ss; /* FE20 (R/O) */
+ struct kvm_smm_seg_state_64 ds; /* FE30 (R/O) */
+ struct kvm_smm_seg_state_64 fs; /* FE40 (R/O) */
+ struct kvm_smm_seg_state_64 gs; /* FE50 (R/O) */
+
+ /* gdtr has only base and limit*/
+ struct kvm_smm_seg_state_64 gdtr; /* FE60 (R/O) */
+ struct kvm_smm_seg_state_64 ldtr; /* FE70 (R/O) */
+
+ /* idtr has only base and limit*/
+ struct kvm_smm_seg_state_64 idtr; /* FE80 (R/O) */
+ struct kvm_smm_seg_state_64 tr; /* FE90 (R/O) */
+
+ /* I/O restart and auto halt restart are not implemented by KVM */
+ u64 io_restart_rip; /* FEA0 (R/O) */
+ u64 io_restart_rcx; /* FEA8 (R/O) */
+ u64 io_restart_rsi; /* FEB0 (R/O) */
+ u64 io_restart_rdi; /* FEB8 (R/O) */
+ u32 io_restart_dword; /* FEC0 (R/O) */
+ u32 reserved1; /* FEC4 */
+ u8 io_instruction_restart; /* FEC8 (R/W) */
+ u8 auto_halt_restart; /* FEC9 (R/W) */
+ u8 reserved2[6]; /* FECA-FECF */
+
+ u64 efer; /* FED0 (R/O) */
+
+ /*
+ * Implemented on AMD only, to store current SVM guest address.
+ * svm_guest_virtual_int has unknown purpose, not implemented.
+ */
+
+ u64 svm_guest_flag; /* FED8 (R/O) */
+ u64 svm_guest_vmcb_gpa; /* FEE0 (R/O) */
+ u64 svm_guest_virtual_int; /* FEE8 (R/O) */
+
+ u32 reserved3[3]; /* FEF0-FEFB */
+ u32 smm_revison; /* FEFC (R/O) */
+ u32 smbase; /* FFF0 (R/W) */
+ u32 reserved4[5]; /* FF04-FF17 */
+
+ /* SSP and SVM fields below are not implemented by KVM */
+ u64 ssp; /* FF18 (R/W) */
+ u64 svm_guest_pat; /* FF20 (R/O) */
+ u64 svm_host_efer; /* FF28 (R/O) */
+ u64 svm_host_cr4; /* FF30 (R/O) */
+ u64 svm_host_cr3; /* FF38 (R/O) */
+ u64 svm_host_cr0; /* FF40 (R/O) */
+
+ u64 cr4; /* FF48 (R/O) */
+ u64 cr3; /* FF50 (R/O) */
+ u64 cr0; /* FF58 (R/O) */
+
+ u64 dr7; /* FF60 (R/O) */
+ u64 dr6; /* FF68 (R/O) */
+
+ u64 rflags; /* FF70 (R/W) */
+ u64 rip; /* FF78 (R/W) */
+
+ /* GPRS in a reversed "natural" X86 order (R15/R14/../RCX/RAX.) */
+ u64 gprs[16]; /* FF80-FFFF (R/W) */
+};
+
+
/* Host execution mode. */
#if defined(CONFIG_X86_32)
#define X86EMUL_MODE_HOST X86EMUL_MODE_PROT32

268
patches/kernel/0021-KVM-x86-emulator-smm-use-smram-struct-for-32-bit-smr.patch Normal file
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@ -0,0 +1,268 @@
From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Maxim Levitsky <mlevitsk@redhat.com>
Date: Tue, 21 Jun 2022 18:08:59 +0300
Subject: [PATCH] KVM: x86: emulator/smm: use smram struct for 32 bit smram
load/restore
Use kvm_smram_state_32 struct to save/restore 32 bit SMM state
(used when X86_FEATURE_LM is not present in the guest CPUID).
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
---
arch/x86/kvm/emulate.c | 81 +++++++++++++++---------------------------
arch/x86/kvm/x86.c | 75 +++++++++++++++++---------------------
2 files changed, 60 insertions(+), 96 deletions(-)
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 38d9bfa650ec..44ce8d51f18b 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -2340,25 +2340,17 @@ static void rsm_set_desc_flags(struct desc_struct *desc, u32 flags)
desc->type = (flags >> 8) & 15;
}
-static int rsm_load_seg_32(struct x86_emulate_ctxt *ctxt, const char *smstate,
+static void rsm_load_seg_32(struct x86_emulate_ctxt *ctxt,
+ struct kvm_smm_seg_state_32 *state,
+ u16 selector,
int n)
{
struct desc_struct desc;
- int offset;
- u16 selector;
-
- selector = GET_SMSTATE(u32, smstate, 0x7fa8 + n * 4);
-
- if (n < 3)
- offset = 0x7f84 + n * 12;
- else
- offset = 0x7f2c + (n - 3) * 12;
- set_desc_base(&desc, GET_SMSTATE(u32, smstate, offset + 8));
- set_desc_limit(&desc, GET_SMSTATE(u32, smstate, offset + 4));
- rsm_set_desc_flags(&desc, GET_SMSTATE(u32, smstate, offset));
+ set_desc_base(&desc, state->base);
+ set_desc_limit(&desc, state->limit);
+ rsm_set_desc_flags(&desc, state->flags);
ctxt->ops->set_segment(ctxt, selector, &desc, 0, n);
- return X86EMUL_CONTINUE;
}
#ifdef CONFIG_X86_64
@@ -2429,63 +2421,46 @@ static int rsm_enter_protected_mode(struct x86_emulate_ctxt *ctxt,
}
static int rsm_load_state_32(struct x86_emulate_ctxt *ctxt,
- const char *smstate)
+ struct kvm_smram_state_32 *smstate)
{
- struct desc_struct desc;
struct desc_ptr dt;
- u16 selector;
- u32 val, cr0, cr3, cr4;
int i;
- cr0 = GET_SMSTATE(u32, smstate, 0x7ffc);
- cr3 = GET_SMSTATE(u32, smstate, 0x7ff8);
- ctxt->eflags = GET_SMSTATE(u32, smstate, 0x7ff4) | X86_EFLAGS_FIXED;
- ctxt->_eip = GET_SMSTATE(u32, smstate, 0x7ff0);
+ ctxt->eflags = smstate->eflags | X86_EFLAGS_FIXED;
+ ctxt->_eip = smstate->eip;
for (i = 0; i < 8; i++)
- *reg_write(ctxt, i) = GET_SMSTATE(u32, smstate, 0x7fd0 + i * 4);
-
- val = GET_SMSTATE(u32, smstate, 0x7fcc);
+ *reg_write(ctxt, i) = smstate->gprs[i];
- if (ctxt->ops->set_dr(ctxt, 6, val))
+ if (ctxt->ops->set_dr(ctxt, 6, smstate->dr6))
return X86EMUL_UNHANDLEABLE;
-
- val = GET_SMSTATE(u32, smstate, 0x7fc8);
-
- if (ctxt->ops->set_dr(ctxt, 7, val))
+ if (ctxt->ops->set_dr(ctxt, 7, smstate->dr7))
return X86EMUL_UNHANDLEABLE;
- selector = GET_SMSTATE(u32, smstate, 0x7fc4);
- set_desc_base(&desc, GET_SMSTATE(u32, smstate, 0x7f64));
- set_desc_limit(&desc, GET_SMSTATE(u32, smstate, 0x7f60));
- rsm_set_desc_flags(&desc, GET_SMSTATE(u32, smstate, 0x7f5c));
- ctxt->ops->set_segment(ctxt, selector, &desc, 0, VCPU_SREG_TR);
+ rsm_load_seg_32(ctxt, &smstate->tr, smstate->tr_sel, VCPU_SREG_TR);
+ rsm_load_seg_32(ctxt, &smstate->ldtr, smstate->ldtr_sel, VCPU_SREG_LDTR);
- selector = GET_SMSTATE(u32, smstate, 0x7fc0);
- set_desc_base(&desc, GET_SMSTATE(u32, smstate, 0x7f80));
- set_desc_limit(&desc, GET_SMSTATE(u32, smstate, 0x7f7c));
- rsm_set_desc_flags(&desc, GET_SMSTATE(u32, smstate, 0x7f78));
- ctxt->ops->set_segment(ctxt, selector, &desc, 0, VCPU_SREG_LDTR);
- dt.address = GET_SMSTATE(u32, smstate, 0x7f74);
- dt.size = GET_SMSTATE(u32, smstate, 0x7f70);
+ dt.address = smstate->gdtr.base;
+ dt.size = smstate->gdtr.limit;
ctxt->ops->set_gdt(ctxt, &dt);
- dt.address = GET_SMSTATE(u32, smstate, 0x7f58);
- dt.size = GET_SMSTATE(u32, smstate, 0x7f54);
+ dt.address = smstate->idtr.base;
+ dt.size = smstate->idtr.limit;
ctxt->ops->set_idt(ctxt, &dt);
- for (i = 0; i < 6; i++) {
- int r = rsm_load_seg_32(ctxt, smstate, i);
- if (r != X86EMUL_CONTINUE)
- return r;
- }
+ rsm_load_seg_32(ctxt, &smstate->es, smstate->es_sel, VCPU_SREG_ES);
+ rsm_load_seg_32(ctxt, &smstate->cs, smstate->cs_sel, VCPU_SREG_CS);
+ rsm_load_seg_32(ctxt, &smstate->ss, smstate->ss_sel, VCPU_SREG_SS);
- cr4 = GET_SMSTATE(u32, smstate, 0x7f14);
+ rsm_load_seg_32(ctxt, &smstate->ds, smstate->ds_sel, VCPU_SREG_DS);
+ rsm_load_seg_32(ctxt, &smstate->fs, smstate->fs_sel, VCPU_SREG_FS);
+ rsm_load_seg_32(ctxt, &smstate->gs, smstate->gs_sel, VCPU_SREG_GS);
- ctxt->ops->set_smbase(ctxt, GET_SMSTATE(u32, smstate, 0x7ef8));
+ ctxt->ops->set_smbase(ctxt, smstate->smbase);
- return rsm_enter_protected_mode(ctxt, cr0, cr3, cr4);
+ return rsm_enter_protected_mode(ctxt, smstate->cr0,
+ smstate->cr3, smstate->cr4);
}
#ifdef CONFIG_X86_64
@@ -2630,7 +2605,7 @@ static int em_rsm(struct x86_emulate_ctxt *ctxt)
ret = rsm_load_state_64(ctxt, buf);
else
#endif
- ret = rsm_load_state_32(ctxt, buf);
+ ret = rsm_load_state_32(ctxt, (struct kvm_smram_state_32 *)buf);
if (ret != X86EMUL_CONTINUE)
goto emulate_shutdown;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 922fc258c37f..b626eb3fa376 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -9018,22 +9018,18 @@ static u32 enter_smm_get_segment_flags(struct kvm_segment *seg)
return flags;
}
-static void enter_smm_save_seg_32(struct kvm_vcpu *vcpu, char *buf, int n)
+static void enter_smm_save_seg_32(struct kvm_vcpu *vcpu,
+ struct kvm_smm_seg_state_32 *state,
+ u32 *selector,
+ int n)
{
struct kvm_segment seg;
- int offset;
kvm_get_segment(vcpu, &seg, n);
- put_smstate(u32, buf, 0x7fa8 + n * 4, seg.selector);
-
- if (n < 3)
- offset = 0x7f84 + n * 12;
- else
- offset = 0x7f2c + (n - 3) * 12;
-
- put_smstate(u32, buf, offset + 8, seg.base);
- put_smstate(u32, buf, offset + 4, seg.limit);
- put_smstate(u32, buf, offset, enter_smm_get_segment_flags(&seg));
+ *selector = seg.selector;
+ state->base = seg.base;
+ state->limit = seg.limit;
+ state->flags = enter_smm_get_segment_flags(&seg);
}
#ifdef CONFIG_X86_64
@@ -9054,54 +9050,47 @@ static void enter_smm_save_seg_64(struct kvm_vcpu *vcpu, char *buf, int n)
}
#endif
-static void enter_smm_save_state_32(struct kvm_vcpu *vcpu, char *buf)
+static void enter_smm_save_state_32(struct kvm_vcpu *vcpu, struct kvm_smram_state_32 *smram)
{
struct desc_ptr dt;
- struct kvm_segment seg;
unsigned long val;
int i;
- put_smstate(u32, buf, 0x7ffc, kvm_read_cr0(vcpu));
- put_smstate(u32, buf, 0x7ff8, kvm_read_cr3(vcpu));
- put_smstate(u32, buf, 0x7ff4, kvm_get_rflags(vcpu));
- put_smstate(u32, buf, 0x7ff0, kvm_rip_read(vcpu));
+ smram->cr0 = kvm_read_cr0(vcpu);
+ smram->cr3 = kvm_read_cr3(vcpu);
+ smram->eflags = kvm_get_rflags(vcpu);
+ smram->eip = kvm_rip_read(vcpu);
for (i = 0; i < 8; i++)
- put_smstate(u32, buf, 0x7fd0 + i * 4, kvm_register_read_raw(vcpu, i));
+ smram->gprs[i] = kvm_register_read_raw(vcpu, i);
kvm_get_dr(vcpu, 6, &val);
- put_smstate(u32, buf, 0x7fcc, (u32)val);
+ smram->dr6 = (u32)val;
kvm_get_dr(vcpu, 7, &val);
- put_smstate(u32, buf, 0x7fc8, (u32)val);
+ smram->dr7 = (u32)val;
- kvm_get_segment(vcpu, &seg, VCPU_SREG_TR);
- put_smstate(u32, buf, 0x7fc4, seg.selector);
- put_smstate(u32, buf, 0x7f64, seg.base);
- put_smstate(u32, buf, 0x7f60, seg.limit);
- put_smstate(u32, buf, 0x7f5c, enter_smm_get_segment_flags(&seg));
-
- kvm_get_segment(vcpu, &seg, VCPU_SREG_LDTR);
- put_smstate(u32, buf, 0x7fc0, seg.selector);
- put_smstate(u32, buf, 0x7f80, seg.base);
- put_smstate(u32, buf, 0x7f7c, seg.limit);
- put_smstate(u32, buf, 0x7f78, enter_smm_get_segment_flags(&seg));
+ enter_smm_save_seg_32(vcpu, &smram->tr, &smram->tr_sel, VCPU_SREG_TR);
+ enter_smm_save_seg_32(vcpu, &smram->ldtr, &smram->ldtr_sel, VCPU_SREG_LDTR);
static_call(kvm_x86_get_gdt)(vcpu, &dt);
- put_smstate(u32, buf, 0x7f74, dt.address);
- put_smstate(u32, buf, 0x7f70, dt.size);
+ smram->gdtr.base = dt.address;
+ smram->gdtr.limit = dt.size;
static_call(kvm_x86_get_idt)(vcpu, &dt);
- put_smstate(u32, buf, 0x7f58, dt.address);
- put_smstate(u32, buf, 0x7f54, dt.size);
+ smram->idtr.base = dt.address;
+ smram->idtr.limit = dt.size;
- for (i = 0; i < 6; i++)
- enter_smm_save_seg_32(vcpu, buf, i);
+ enter_smm_save_seg_32(vcpu, &smram->es, &smram->es_sel, VCPU_SREG_ES);
+ enter_smm_save_seg_32(vcpu, &smram->cs, &smram->cs_sel, VCPU_SREG_CS);
+ enter_smm_save_seg_32(vcpu, &smram->ss, &smram->ss_sel, VCPU_SREG_SS);
- put_smstate(u32, buf, 0x7f14, kvm_read_cr4(vcpu));
+ enter_smm_save_seg_32(vcpu, &smram->ds, &smram->ds_sel, VCPU_SREG_DS);
+ enter_smm_save_seg_32(vcpu, &smram->fs, &smram->fs_sel, VCPU_SREG_FS);
+ enter_smm_save_seg_32(vcpu, &smram->gs, &smram->gs_sel, VCPU_SREG_GS);
- /* revision id */
- put_smstate(u32, buf, 0x7efc, 0x00020000);
- put_smstate(u32, buf, 0x7ef8, vcpu->arch.smbase);
+ smram->cr4 = kvm_read_cr4(vcpu);
+ smram->smm_revision = 0x00020000;
+ smram->smbase = vcpu->arch.smbase;
}
#ifdef CONFIG_X86_64
@@ -9172,7 +9161,7 @@ static void enter_smm(struct kvm_vcpu *vcpu)
enter_smm_save_state_64(vcpu, buf);
else
#endif
- enter_smm_save_state_32(vcpu, buf);
+ enter_smm_save_state_32(vcpu, (struct kvm_smram_state_32 *)buf);
/*
* Give enter_smm() a chance to make ISA-specific changes to the vCPU

279
patches/kernel/0022-KVM-x86-emulator-smm-use-smram-struct-for-64-bit-smr.patch Normal file
View File

@ -0,0 +1,279 @@
From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Maxim Levitsky <mlevitsk@redhat.com>
Date: Tue, 21 Jun 2022 18:09:00 +0300
Subject: [PATCH] KVM: x86: emulator/smm: use smram struct for 64 bit smram
load/restore
Use kvm_smram_state_64 struct to save/restore the 64 bit SMM state
(used when X86_FEATURE_LM is present in the guest CPUID,
regardless of 32-bitness of the guest).
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
---
arch/x86/kvm/emulate.c | 88 ++++++++++++++----------------------------
arch/x86/kvm/x86.c | 75 ++++++++++++++++-------------------
2 files changed, 62 insertions(+), 101 deletions(-)
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 44ce8d51f18b..98c2cf169b39 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -2354,24 +2354,16 @@ static void rsm_load_seg_32(struct x86_emulate_ctxt *ctxt,
}
#ifdef CONFIG_X86_64
-static int rsm_load_seg_64(struct x86_emulate_ctxt *ctxt, const char *smstate,
- int n)
+static void rsm_load_seg_64(struct x86_emulate_ctxt *ctxt,
+ struct kvm_smm_seg_state_64 *state,
+ int n)
{
struct desc_struct desc;
- int offset;
- u16 selector;
- u32 base3;
-
- offset = 0x7e00 + n * 16;
-
- selector = GET_SMSTATE(u16, smstate, offset);
- rsm_set_desc_flags(&desc, GET_SMSTATE(u16, smstate, offset + 2) << 8);
- set_desc_limit(&desc, GET_SMSTATE(u32, smstate, offset + 4));
- set_desc_base(&desc, GET_SMSTATE(u32, smstate, offset + 8));
- base3 = GET_SMSTATE(u32, smstate, offset + 12);
- ctxt->ops->set_segment(ctxt, selector, &desc, base3, n);
- return X86EMUL_CONTINUE;
+ rsm_set_desc_flags(&desc, state->attributes << 8);
+ set_desc_limit(&desc, state->limit);
+ set_desc_base(&desc, (u32)state->base);
+ ctxt->ops->set_segment(ctxt, state->selector, &desc, state->base >> 32, n);
}
#endif
@@ -2465,71 +2457,49 @@ static int rsm_load_state_32(struct x86_emulate_ctxt *ctxt,
#ifdef CONFIG_X86_64
static int rsm_load_state_64(struct x86_emulate_ctxt *ctxt,
- const char *smstate)
+ struct kvm_smram_state_64 *smstate)
{
- struct desc_struct desc;
struct desc_ptr dt;
- u64 val, cr0, cr3, cr4;
- u32 base3;
- u16 selector;
int i, r;
for (i = 0; i < 16; i++)
- *reg_write(ctxt, i) = GET_SMSTATE(u64, smstate, 0x7ff8 - i * 8);
+ *reg_write(ctxt, i) = smstate->gprs[15 - i];
- ctxt->_eip = GET_SMSTATE(u64, smstate, 0x7f78);
- ctxt->eflags = GET_SMSTATE(u32, smstate, 0x7f70) | X86_EFLAGS_FIXED;
+ ctxt->_eip = smstate->rip;
+ ctxt->eflags = smstate->rflags | X86_EFLAGS_FIXED;
- val = GET_SMSTATE(u64, smstate, 0x7f68);
-
- if (ctxt->ops->set_dr(ctxt, 6, val))
+ if (ctxt->ops->set_dr(ctxt, 6, smstate->dr6))
return X86EMUL_UNHANDLEABLE;
-
- val = GET_SMSTATE(u64, smstate, 0x7f60);
-
- if (ctxt->ops->set_dr(ctxt, 7, val))
+ if (ctxt->ops->set_dr(ctxt, 7, smstate->dr7))
return X86EMUL_UNHANDLEABLE;
- cr0 = GET_SMSTATE(u64, smstate, 0x7f58);
- cr3 = GET_SMSTATE(u64, smstate, 0x7f50);
- cr4 = GET_SMSTATE(u64, smstate, 0x7f48);
- ctxt->ops->set_smbase(ctxt, GET_SMSTATE(u32, smstate, 0x7f00));
- val = GET_SMSTATE(u64, smstate, 0x7ed0);
+ ctxt->ops->set_smbase(ctxt, smstate->smbase);
- if (ctxt->ops->set_msr(ctxt, MSR_EFER, val & ~EFER_LMA))
+ if (ctxt->ops->set_msr(ctxt, MSR_EFER, smstate->efer & ~EFER_LMA))
return X86EMUL_UNHANDLEABLE;
- selector = GET_SMSTATE(u32, smstate, 0x7e90);
- rsm_set_desc_flags(&desc, GET_SMSTATE(u32, smstate, 0x7e92) << 8);
- set_desc_limit(&desc, GET_SMSTATE(u32, smstate, 0x7e94));
- set_desc_base(&desc, GET_SMSTATE(u32, smstate, 0x7e98));
- base3 = GET_SMSTATE(u32, smstate, 0x7e9c);
- ctxt->ops->set_segment(ctxt, selector, &desc, base3, VCPU_SREG_TR);
+ rsm_load_seg_64(ctxt, &smstate->tr, VCPU_SREG_TR);
- dt.size = GET_SMSTATE(u32, smstate, 0x7e84);
- dt.address = GET_SMSTATE(u64, smstate, 0x7e88);
+ dt.size = smstate->idtr.limit;
+ dt.address = smstate->idtr.base;
ctxt->ops->set_idt(ctxt, &dt);
- selector = GET_SMSTATE(u32, smstate, 0x7e70);
- rsm_set_desc_flags(&desc, GET_SMSTATE(u32, smstate, 0x7e72) << 8);
- set_desc_limit(&desc, GET_SMSTATE(u32, smstate, 0x7e74));
- set_desc_base(&desc, GET_SMSTATE(u32, smstate, 0x7e78));
- base3 = GET_SMSTATE(u32, smstate, 0x7e7c);
- ctxt->ops->set_segment(ctxt, selector, &desc, base3, VCPU_SREG_LDTR);
+ rsm_load_seg_64(ctxt, &smstate->ldtr, VCPU_SREG_LDTR);
- dt.size = GET_SMSTATE(u32, smstate, 0x7e64);
- dt.address = GET_SMSTATE(u64, smstate, 0x7e68);
+ dt.size = smstate->gdtr.limit;
+ dt.address = smstate->gdtr.base;
ctxt->ops->set_gdt(ctxt, &dt);
- r = rsm_enter_protected_mode(ctxt, cr0, cr3, cr4);
+ r = rsm_enter_protected_mode(ctxt, smstate->cr0, smstate->cr3, smstate->cr4);
if (r != X86EMUL_CONTINUE)
return r;
- for (i = 0; i < 6; i++) {
- r = rsm_load_seg_64(ctxt, smstate, i);
- if (r != X86EMUL_CONTINUE)
- return r;
- }
+ rsm_load_seg_64(ctxt, &smstate->es, VCPU_SREG_ES);
+ rsm_load_seg_64(ctxt, &smstate->cs, VCPU_SREG_CS);
+ rsm_load_seg_64(ctxt, &smstate->ss, VCPU_SREG_SS);
+ rsm_load_seg_64(ctxt, &smstate->ds, VCPU_SREG_DS);
+ rsm_load_seg_64(ctxt, &smstate->fs, VCPU_SREG_FS);
+ rsm_load_seg_64(ctxt, &smstate->gs, VCPU_SREG_GS);
return X86EMUL_CONTINUE;
}
@@ -2602,7 +2572,7 @@ static int em_rsm(struct x86_emulate_ctxt *ctxt)
#ifdef CONFIG_X86_64
if (emulator_has_longmode(ctxt))
- ret = rsm_load_state_64(ctxt, buf);
+ ret = rsm_load_state_64(ctxt, (struct kvm_smram_state_64 *)buf);
else
#endif
ret = rsm_load_state_32(ctxt, (struct kvm_smram_state_32 *)buf);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index b626eb3fa376..f40cd45b6a01 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -9033,20 +9033,17 @@ static void enter_smm_save_seg_32(struct kvm_vcpu *vcpu,
}
#ifdef CONFIG_X86_64
-static void enter_smm_save_seg_64(struct kvm_vcpu *vcpu, char *buf, int n)
+static void enter_smm_save_seg_64(struct kvm_vcpu *vcpu,
+ struct kvm_smm_seg_state_64 *state,
+ int n)
{
struct kvm_segment seg;
- int offset;
- u16 flags;
kvm_get_segment(vcpu, &seg, n);
- offset = 0x7e00 + n * 16;
-
- flags = enter_smm_get_segment_flags(&seg) >> 8;
- put_smstate(u16, buf, offset, seg.selector);
- put_smstate(u16, buf, offset + 2, flags);
- put_smstate(u32, buf, offset + 4, seg.limit);
- put_smstate(u64, buf, offset + 8, seg.base);
+ state->selector = seg.selector;
+ state->attributes = enter_smm_get_segment_flags(&seg) >> 8;
+ state->limit = seg.limit;
+ state->base = seg.base;
}
#endif
@@ -9094,57 +9091,51 @@ static void enter_smm_save_state_32(struct kvm_vcpu *vcpu, struct kvm_smram_stat
}
#ifdef CONFIG_X86_64
-static void enter_smm_save_state_64(struct kvm_vcpu *vcpu, char *buf)
+static void enter_smm_save_state_64(struct kvm_vcpu *vcpu, struct kvm_smram_state_64 *smram)
{
struct desc_ptr dt;
- struct kvm_segment seg;
unsigned long val;
int i;
for (i = 0; i < 16; i++)
- put_smstate(u64, buf, 0x7ff8 - i * 8, kvm_register_read_raw(vcpu, i));
+ smram->gprs[15 - i] = kvm_register_read_raw(vcpu, i);
+
+ smram->rip = kvm_rip_read(vcpu);
+ smram->rflags = kvm_get_rflags(vcpu);
- put_smstate(u64, buf, 0x7f78, kvm_rip_read(vcpu));
- put_smstate(u32, buf, 0x7f70, kvm_get_rflags(vcpu));
kvm_get_dr(vcpu, 6, &val);
- put_smstate(u64, buf, 0x7f68, val);
+ smram->dr6 = val;
kvm_get_dr(vcpu, 7, &val);
- put_smstate(u64, buf, 0x7f60, val);
-
- put_smstate(u64, buf, 0x7f58, kvm_read_cr0(vcpu));
- put_smstate(u64, buf, 0x7f50, kvm_read_cr3(vcpu));
- put_smstate(u64, buf, 0x7f48, kvm_read_cr4(vcpu));
+ smram->dr7 = val;
- put_smstate(u32, buf, 0x7f00, vcpu->arch.smbase);
+ smram->cr0 = kvm_read_cr0(vcpu);
+ smram->cr3 = kvm_read_cr3(vcpu);
+ smram->cr4 = kvm_read_cr4(vcpu);
- /* revision id */
- put_smstate(u32, buf, 0x7efc, 0x00020064);
+ smram->smbase = vcpu->arch.smbase;
+ smram->smm_revison = 0x00020064;
- put_smstate(u64, buf, 0x7ed0, vcpu->arch.efer);
+ smram->efer = vcpu->arch.efer;
- kvm_get_segment(vcpu, &seg, VCPU_SREG_TR);
- put_smstate(u16, buf, 0x7e90, seg.selector);
- put_smstate(u16, buf, 0x7e92, enter_smm_get_segment_flags(&seg) >> 8);
- put_smstate(u32, buf, 0x7e94, seg.limit);
- put_smstate(u64, buf, 0x7e98, seg.base);
+ enter_smm_save_seg_64(vcpu, &smram->tr, VCPU_SREG_TR);
static_call(kvm_x86_get_idt)(vcpu, &dt);
- put_smstate(u32, buf, 0x7e84, dt.size);
- put_smstate(u64, buf, 0x7e88, dt.address);
+ smram->idtr.limit = dt.size;
+ smram->idtr.base = dt.address;
- kvm_get_segment(vcpu, &seg, VCPU_SREG_LDTR);
- put_smstate(u16, buf, 0x7e70, seg.selector);
- put_smstate(u16, buf, 0x7e72, enter_smm_get_segment_flags(&seg) >> 8);
- put_smstate(u32, buf, 0x7e74, seg.limit);
- put_smstate(u64, buf, 0x7e78, seg.base);
+ enter_smm_save_seg_64(vcpu, &smram->ldtr, VCPU_SREG_LDTR);
static_call(kvm_x86_get_gdt)(vcpu, &dt);
- put_smstate(u32, buf, 0x7e64, dt.size);
- put_smstate(u64, buf, 0x7e68, dt.address);
+ smram->gdtr.limit = dt.size;
+ smram->gdtr.base = dt.address;
- for (i = 0; i < 6; i++)
- enter_smm_save_seg_64(vcpu, buf, i);
+ enter_smm_save_seg_64(vcpu, &smram->es, VCPU_SREG_ES);
+ enter_smm_save_seg_64(vcpu, &smram->cs, VCPU_SREG_CS);
+ enter_smm_save_seg_64(vcpu, &smram->ss, VCPU_SREG_SS);
+ enter_smm_save_seg_64(vcpu, &smram->ds, VCPU_SREG_DS);
+ enter_smm_save_seg_64(vcpu, &smram->fs, VCPU_SREG_FS);
+ enter_smm_save_seg_64(vcpu, &smram->gs, VCPU_SREG_GS);
}
#endif
@@ -9158,7 +9149,7 @@ static void enter_smm(struct kvm_vcpu *vcpu)
memset(buf, 0, 512);
#ifdef CONFIG_X86_64
if (guest_cpuid_has(vcpu, X86_FEATURE_LM))
- enter_smm_save_state_64(vcpu, buf);
+ enter_smm_save_state_64(vcpu, (struct kvm_smram_state_64 *)buf);
else
#endif
enter_smm_save_state_32(vcpu, (struct kvm_smram_state_32 *)buf);

111
patches/kernel/0023-KVM-x86-SVM-use-smram-structs.patch Normal file
View File

@ -0,0 +1,111 @@
From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Maxim Levitsky <mlevitsk@redhat.com>
Date: Tue, 21 Jun 2022 18:09:01 +0300
Subject: [PATCH] KVM: x86: SVM: use smram structs
This removes the last user of put_smstate/GET_SMSTATE so
remove these functions as well.
Also add a sanity check that we don't attempt to enter the SMM
on non long mode capable guest CPU with a running nested guest.
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
---
arch/x86/include/asm/kvm_host.h | 6 ------
arch/x86/kvm/svm/svm.c | 28 +++++++++++++++++-----------
2 files changed, 17 insertions(+), 17 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 867febee8fc3..4b443624b884 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1931,12 +1931,6 @@ static inline int kvm_cpu_get_apicid(int mps_cpu)
#endif
}
-#define put_smstate(type, buf, offset, val) \
- *(type *)((buf) + (offset) - 0x7e00) = val
-
-#define GET_SMSTATE(type, buf, offset) \
- (*(type *)((buf) + (offset) - 0x7e00))
-
int kvm_cpu_dirty_log_size(void);
int alloc_all_memslots_rmaps(struct kvm *kvm);
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 21f747eacc9a..283b1ca95317 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -4304,6 +4304,7 @@ static int svm_smi_allowed(struct kvm_vcpu *vcpu, bool for_injection)
static int svm_enter_smm(struct kvm_vcpu *vcpu, char *smstate)
{
+ struct kvm_smram_state_64 *smram = (struct kvm_smram_state_64 *)smstate;
struct vcpu_svm *svm = to_svm(vcpu);
struct kvm_host_map map_save;
int ret;
@@ -4311,10 +4312,17 @@ static int svm_enter_smm(struct kvm_vcpu *vcpu, char *smstate)
if (!is_guest_mode(vcpu))
return 0;
- /* FED8h - SVM Guest */
- put_smstate(u64, smstate, 0x7ed8, 1);
- /* FEE0h - SVM Guest VMCB Physical Address */
- put_smstate(u64, smstate, 0x7ee0, svm->nested.vmcb12_gpa);
+ /*
+ * 32 bit SMRAM format doesn't preserve EFER and SVM state.
+ * SVM should not be enabled by the userspace without marking
+ * the CPU as at least long mode capable.
+ */
+
+ if (!guest_cpuid_has(vcpu, X86_FEATURE_SVM))
+ return 1;
+
+ smram->svm_guest_flag = 1;
+ smram->svm_guest_vmcb_gpa = svm->nested.vmcb12_gpa;
svm->vmcb->save.rax = vcpu->arch.regs[VCPU_REGS_RAX];
svm->vmcb->save.rsp = vcpu->arch.regs[VCPU_REGS_RSP];
@@ -4351,9 +4359,9 @@ static int svm_enter_smm(struct kvm_vcpu *vcpu, char *smstate)
static int svm_leave_smm(struct kvm_vcpu *vcpu, const char *smstate)
{
+ struct kvm_smram_state_64 *smram = (struct kvm_smram_state_64 *)smstate;
struct vcpu_svm *svm = to_svm(vcpu);
struct kvm_host_map map, map_save;
- u64 saved_efer, vmcb12_gpa;
struct vmcb *vmcb12;
int ret;
@@ -4361,18 +4369,16 @@ static int svm_leave_smm(struct kvm_vcpu *vcpu, const char *smstate)
return 0;
/* Non-zero if SMI arrived while vCPU was in guest mode. */
- if (!GET_SMSTATE(u64, smstate, 0x7ed8))
+ if (!smram->svm_guest_flag)
return 0;
if (!guest_cpuid_has(vcpu, X86_FEATURE_SVM))
return 1;
- saved_efer = GET_SMSTATE(u64, smstate, 0x7ed0);
- if (!(saved_efer & EFER_SVME))
+ if (!(smram->efer & EFER_SVME))
return 1;
- vmcb12_gpa = GET_SMSTATE(u64, smstate, 0x7ee0);
- if (kvm_vcpu_map(vcpu, gpa_to_gfn(vmcb12_gpa), &map) == -EINVAL)
+ if (kvm_vcpu_map(vcpu, gpa_to_gfn(smram->svm_guest_vmcb_gpa), &map) == -EINVAL)
return 1;
ret = 1;
@@ -4397,7 +4403,7 @@ static int svm_leave_smm(struct kvm_vcpu *vcpu, const char *smstate)
vmcb12 = map.hva;
nested_load_control_from_vmcb12(svm, &vmcb12->control);
- ret = enter_svm_guest_mode(vcpu, vmcb12_gpa, vmcb12, false);
+ ret = enter_svm_guest_mode(vcpu, smram->svm_guest_vmcb_gpa, vmcb12, false);
if (ret)
goto unmap_save;

167
patches/kernel/0024-KVM-x86-emulator-smm-preserve-interrupt-shadow-in-SM.patch Normal file
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@ -0,0 +1,167 @@
From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Maxim Levitsky <mlevitsk@redhat.com>
Date: Tue, 21 Jun 2022 18:09:02 +0300
Subject: [PATCH] KVM: x86: emulator/smm: preserve interrupt shadow in SMRAM
When #SMI is asserted, the CPU can be in interrupt shadow
due to sti or mov ss.
It is not mandatory in Intel/AMD prm to have the #SMI
blocked during the shadow, and on top of
that, since neither SVM nor VMX has true support for SMI
window, waiting for one instruction would mean single stepping
the guest.
Instead, allow #SMI in this case, but both reset the interrupt
window and stash its value in SMRAM to restore it on exit
from SMM.
This fixes rare failures seen mostly on windows guests on VMX,
when #SMI falls on the sti instruction which mainfest in
VM entry failure due to EFLAGS.IF not being set, but STI interrupt
window still being set in the VMCS.
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
---
arch/x86/kvm/emulate.c | 17 ++++++++++++++---
arch/x86/kvm/kvm_emulate.h | 13 ++++++++++---
arch/x86/kvm/x86.c | 12 ++++++++++++
3 files changed, 36 insertions(+), 6 deletions(-)
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 98c2cf169b39..5614456de922 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -2416,7 +2416,7 @@ static int rsm_load_state_32(struct x86_emulate_ctxt *ctxt,
struct kvm_smram_state_32 *smstate)
{
struct desc_ptr dt;
- int i;
+ int i, r;
ctxt->eflags = smstate->eflags | X86_EFLAGS_FIXED;
ctxt->_eip = smstate->eip;
@@ -2451,8 +2451,16 @@ static int rsm_load_state_32(struct x86_emulate_ctxt *ctxt,
ctxt->ops->set_smbase(ctxt, smstate->smbase);
- return rsm_enter_protected_mode(ctxt, smstate->cr0,
- smstate->cr3, smstate->cr4);
+ r = rsm_enter_protected_mode(ctxt, smstate->cr0,
+ smstate->cr3, smstate->cr4);
+
+ if (r != X86EMUL_CONTINUE)
+ return r;
+
+ ctxt->ops->set_int_shadow(ctxt, 0);
+ ctxt->interruptibility = (u8)smstate->int_shadow;
+
+ return X86EMUL_CONTINUE;
}
#ifdef CONFIG_X86_64
@@ -2501,6 +2509,9 @@ static int rsm_load_state_64(struct x86_emulate_ctxt *ctxt,
rsm_load_seg_64(ctxt, &smstate->fs, VCPU_SREG_FS);
rsm_load_seg_64(ctxt, &smstate->gs, VCPU_SREG_GS);
+ ctxt->ops->set_int_shadow(ctxt, 0);
+ ctxt->interruptibility = (u8)smstate->int_shadow;
+
return X86EMUL_CONTINUE;
}
#endif
diff --git a/arch/x86/kvm/kvm_emulate.h b/arch/x86/kvm/kvm_emulate.h
index d16b377be70b..5b881a3a5ed9 100644
--- a/arch/x86/kvm/kvm_emulate.h
+++ b/arch/x86/kvm/kvm_emulate.h
@@ -229,6 +229,7 @@ struct x86_emulate_ops {
bool (*guest_has_rdpid)(struct x86_emulate_ctxt *ctxt);
void (*set_nmi_mask)(struct x86_emulate_ctxt *ctxt, bool masked);
+ void (*set_int_shadow)(struct x86_emulate_ctxt *ctxt, u8 shadow);
unsigned (*get_hflags)(struct x86_emulate_ctxt *ctxt);
void (*exiting_smm)(struct x86_emulate_ctxt *ctxt);
@@ -499,7 +500,9 @@ struct kvm_smram_state_32 {
u32 reserved1[62]; /* FE00 - FEF7 */
u32 smbase; /* FEF8 */
u32 smm_revision; /* FEFC */
- u32 reserved2[5]; /* FF00-FF13 */
+ u32 reserved2[4]; /* FF00-FF0F*/
+ /* int_shadow is KVM extension*/
+ u32 int_shadow; /* FF10 */
/* CR4 is not present in Intel/AMD SMRAM image*/
u32 cr4; /* FF14 */
u32 reserved3[5]; /* FF18 */
@@ -571,13 +574,17 @@ struct kvm_smram_state_64 {
struct kvm_smm_seg_state_64 idtr; /* FE80 (R/O) */
struct kvm_smm_seg_state_64 tr; /* FE90 (R/O) */
- /* I/O restart and auto halt restart are not implemented by KVM */
+ /*
+ * I/O restart and auto halt restart are not implemented by KVM
+ * int_shadow is KVM's extension
+ */
+
u64 io_restart_rip; /* FEA0 (R/O) */
u64 io_restart_rcx; /* FEA8 (R/O) */
u64 io_restart_rsi; /* FEB0 (R/O) */
u64 io_restart_rdi; /* FEB8 (R/O) */
u32 io_restart_dword; /* FEC0 (R/O) */
- u32 reserved1; /* FEC4 */
+ u32 int_shadow; /* FEC4 (R/O) */
u8 io_instruction_restart; /* FEC8 (R/W) */
u8 auto_halt_restart; /* FEC9 (R/W) */
u8 reserved2[6]; /* FECA-FECF */
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index f40cd45b6a01..9afac97ea98c 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -7299,6 +7299,11 @@ static void emulator_set_nmi_mask(struct x86_emulate_ctxt *ctxt, bool masked)
static_call(kvm_x86_set_nmi_mask)(emul_to_vcpu(ctxt), masked);
}
+static void emulator_set_int_shadow(struct x86_emulate_ctxt *ctxt, u8 shadow)
+{
+ static_call(kvm_x86_set_interrupt_shadow)(emul_to_vcpu(ctxt), shadow);
+}
+
static unsigned emulator_get_hflags(struct x86_emulate_ctxt *ctxt)
{
return emul_to_vcpu(ctxt)->arch.hflags;
@@ -7368,6 +7373,7 @@ static const struct x86_emulate_ops emulate_ops = {
.guest_has_fxsr = emulator_guest_has_fxsr,
.guest_has_rdpid = emulator_guest_has_rdpid,
.set_nmi_mask = emulator_set_nmi_mask,
+ .set_int_shadow = emulator_set_int_shadow,
.get_hflags = emulator_get_hflags,
.exiting_smm = emulator_exiting_smm,
.leave_smm = emulator_leave_smm,
@@ -9088,6 +9094,8 @@ static void enter_smm_save_state_32(struct kvm_vcpu *vcpu, struct kvm_smram_stat
smram->cr4 = kvm_read_cr4(vcpu);
smram->smm_revision = 0x00020000;
smram->smbase = vcpu->arch.smbase;
+
+ smram->int_shadow = static_call(kvm_x86_get_interrupt_shadow)(vcpu);
}
#ifdef CONFIG_X86_64
@@ -9136,6 +9144,8 @@ static void enter_smm_save_state_64(struct kvm_vcpu *vcpu, struct kvm_smram_stat
enter_smm_save_seg_64(vcpu, &smram->ds, VCPU_SREG_DS);
enter_smm_save_seg_64(vcpu, &smram->fs, VCPU_SREG_FS);
enter_smm_save_seg_64(vcpu, &smram->gs, VCPU_SREG_GS);
+
+ smram->int_shadow = static_call(kvm_x86_get_interrupt_shadow)(vcpu);
}
#endif
@@ -9172,6 +9182,8 @@ static void enter_smm(struct kvm_vcpu *vcpu)
kvm_set_rflags(vcpu, X86_EFLAGS_FIXED);
kvm_rip_write(vcpu, 0x8000);
+ static_call(kvm_x86_set_interrupt_shadow)(vcpu, 0);
+
cr0 = vcpu->arch.cr0 & ~(X86_CR0_PE | X86_CR0_EM | X86_CR0_TS | X86_CR0_PG);
static_call(kvm_x86_set_cr0)(vcpu, cr0);
vcpu->arch.cr0 = cr0;