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authorLinus Torvalds <torvalds@linux-foundation.org>2017-06-22 11:03:09 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2017-06-22 11:03:09 -0700
commit3f7ba7e13e70bbcba1af568dc105c1a4243b33c7 (patch)
tree91c46e6df39ce5ba518a2f72ba987ec43a6daf63
parent4f92f0e25a48212ae06e0761504ee0c9c23776ee (diff)
parentc8401dda2f0a00cd25c0af6a95ed50e478d25de4 (diff)
downloadlinux-sh-3f7ba7e13e70bbcba1af568dc105c1a4243b33c7.tar.gz
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM fixes from Radim Krčmář: "MIPS: - Fix build with KVM, DYNAMIC_DEBUG and JUMP_LABEL. PPC: - Fix host crashes/hangs on POWER9. - Properly restore userspace state after KVM_RUN ioctl. s390: - Fix address translation in odd-ball cases (real-space designation ASCEs). x86: - Fix privilege escalation in 64-bit Windows guests All patches are for stable and the x86 also has a CVE" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: x86: fix singlestepping over syscall KVM: s390: gaccess: fix real-space designation asce handling for gmap shadows KVM: MIPS: Fix maybe-uninitialized build failure KVM: PPC: Book3S HV: Ignore timebase offset on POWER9 DD1 KVM: PPC: Book3S HV: Save/restore host values of debug registers KVM: PPC: Book3S HV: Preserve userspace HTM state properly KVM: PPC: Book3S HV: Restore critical SPRs to host values on guest exit KVM: PPC: Book3S HV: Context-switch EBB registers properly KVM: PPC: Book3S HV: Cope with host using large decrementer mode
-rw-r--r--arch/mips/kvm/tlb.c6
-rw-r--r--arch/powerpc/kvm/book3s_hv.c51
-rw-r--r--arch/powerpc/kvm/book3s_hv_interrupts.S12
-rw-r--r--arch/powerpc/kvm/book3s_hv_rmhandlers.S75
-rw-r--r--arch/s390/kvm/gaccess.c15
-rw-r--r--arch/x86/include/asm/kvm_emulate.h1
-rw-r--r--arch/x86/kvm/emulate.c1
-rw-r--r--arch/x86/kvm/x86.c62
8 files changed, 163 insertions, 60 deletions
diff --git a/arch/mips/kvm/tlb.c b/arch/mips/kvm/tlb.c
index 7c6336dd2638..7cd92166a0b9 100644
--- a/arch/mips/kvm/tlb.c
+++ b/arch/mips/kvm/tlb.c
@@ -166,7 +166,11 @@ static int _kvm_mips_host_tlb_inv(unsigned long entryhi)
int kvm_mips_host_tlb_inv(struct kvm_vcpu *vcpu, unsigned long va,
bool user, bool kernel)
{
- int idx_user, idx_kernel;
+ /*
+ * Initialize idx_user and idx_kernel to workaround bogus
+ * maybe-initialized warning when using GCC 6.
+ */
+ int idx_user = 0, idx_kernel = 0;
unsigned long flags, old_entryhi;
local_irq_save(flags);
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 42b7a4fd57d9..8d1a365b8edc 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -1486,6 +1486,14 @@ static int kvmppc_set_one_reg_hv(struct kvm_vcpu *vcpu, u64 id,
r = set_vpa(vcpu, &vcpu->arch.dtl, addr, len);
break;
case KVM_REG_PPC_TB_OFFSET:
+ /*
+ * POWER9 DD1 has an erratum where writing TBU40 causes
+ * the timebase to lose ticks. So we don't let the
+ * timebase offset be changed on P9 DD1. (It is
+ * initialized to zero.)
+ */
+ if (cpu_has_feature(CPU_FTR_POWER9_DD1))
+ break;
/* round up to multiple of 2^24 */
vcpu->arch.vcore->tb_offset =
ALIGN(set_reg_val(id, *val), 1UL << 24);
@@ -2907,12 +2915,36 @@ static int kvmppc_vcpu_run_hv(struct kvm_run *run, struct kvm_vcpu *vcpu)
{
int r;
int srcu_idx;
+ unsigned long ebb_regs[3] = {}; /* shut up GCC */
+ unsigned long user_tar = 0;
+ unsigned int user_vrsave;
if (!vcpu->arch.sane) {
run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
return -EINVAL;
}
+ /*
+ * Don't allow entry with a suspended transaction, because
+ * the guest entry/exit code will lose it.
+ * If the guest has TM enabled, save away their TM-related SPRs
+ * (they will get restored by the TM unavailable interrupt).
+ */
+#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
+ if (cpu_has_feature(CPU_FTR_TM) && current->thread.regs &&
+ (current->thread.regs->msr & MSR_TM)) {
+ if (MSR_TM_ACTIVE(current->thread.regs->msr)) {
+ run->exit_reason = KVM_EXIT_FAIL_ENTRY;
+ run->fail_entry.hardware_entry_failure_reason = 0;
+ return -EINVAL;
+ }
+ current->thread.tm_tfhar = mfspr(SPRN_TFHAR);
+ current->thread.tm_tfiar = mfspr(SPRN_TFIAR);
+ current->thread.tm_texasr = mfspr(SPRN_TEXASR);
+ current->thread.regs->msr &= ~MSR_TM;
+ }
+#endif
+
kvmppc_core_prepare_to_enter(vcpu);
/* No need to go into the guest when all we'll do is come back out */
@@ -2934,6 +2966,15 @@ static int kvmppc_vcpu_run_hv(struct kvm_run *run, struct kvm_vcpu *vcpu)
flush_all_to_thread(current);
+ /* Save userspace EBB and other register values */
+ if (cpu_has_feature(CPU_FTR_ARCH_207S)) {
+ ebb_regs[0] = mfspr(SPRN_EBBHR);
+ ebb_regs[1] = mfspr(SPRN_EBBRR);
+ ebb_regs[2] = mfspr(SPRN_BESCR);
+ user_tar = mfspr(SPRN_TAR);
+ }
+ user_vrsave = mfspr(SPRN_VRSAVE);
+
vcpu->arch.wqp = &vcpu->arch.vcore->wq;
vcpu->arch.pgdir = current->mm->pgd;
vcpu->arch.state = KVMPPC_VCPU_BUSY_IN_HOST;
@@ -2960,6 +3001,16 @@ static int kvmppc_vcpu_run_hv(struct kvm_run *run, struct kvm_vcpu *vcpu)
}
} while (is_kvmppc_resume_guest(r));
+ /* Restore userspace EBB and other register values */
+ if (cpu_has_feature(CPU_FTR_ARCH_207S)) {
+ mtspr(SPRN_EBBHR, ebb_regs[0]);
+ mtspr(SPRN_EBBRR, ebb_regs[1]);
+ mtspr(SPRN_BESCR, ebb_regs[2]);
+ mtspr(SPRN_TAR, user_tar);
+ mtspr(SPRN_FSCR, current->thread.fscr);
+ }
+ mtspr(SPRN_VRSAVE, user_vrsave);
+
out:
vcpu->arch.state = KVMPPC_VCPU_NOTREADY;
atomic_dec(&vcpu->kvm->arch.vcpus_running);
diff --git a/arch/powerpc/kvm/book3s_hv_interrupts.S b/arch/powerpc/kvm/book3s_hv_interrupts.S
index 0fdc4a28970b..404deb512844 100644
--- a/arch/powerpc/kvm/book3s_hv_interrupts.S
+++ b/arch/powerpc/kvm/book3s_hv_interrupts.S
@@ -121,10 +121,20 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
* Put whatever is in the decrementer into the
* hypervisor decrementer.
*/
+BEGIN_FTR_SECTION
+ ld r5, HSTATE_KVM_VCORE(r13)
+ ld r6, VCORE_KVM(r5)
+ ld r9, KVM_HOST_LPCR(r6)
+ andis. r9, r9, LPCR_LD@h
+END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
mfspr r8,SPRN_DEC
mftb r7
- mtspr SPRN_HDEC,r8
+BEGIN_FTR_SECTION
+ /* On POWER9, don't sign-extend if host LPCR[LD] bit is set */
+ bne 32f
+END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
extsw r8,r8
+32: mtspr SPRN_HDEC,r8
add r8,r8,r7
std r8,HSTATE_DECEXP(r13)
diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index bdb3f76ceb6b..4888dd494604 100644
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -32,12 +32,29 @@
#include <asm/opal.h>
#include <asm/xive-regs.h>
+/* Sign-extend HDEC if not on POWER9 */
+#define EXTEND_HDEC(reg) \
+BEGIN_FTR_SECTION; \
+ extsw reg, reg; \
+END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300)
+
#define VCPU_GPRS_TM(reg) (((reg) * ULONG_SIZE) + VCPU_GPR_TM)
/* Values in HSTATE_NAPPING(r13) */
#define NAPPING_CEDE 1
#define NAPPING_NOVCPU 2
+/* Stack frame offsets for kvmppc_hv_entry */
+#define SFS 144
+#define STACK_SLOT_TRAP (SFS-4)
+#define STACK_SLOT_TID (SFS-16)
+#define STACK_SLOT_PSSCR (SFS-24)
+#define STACK_SLOT_PID (SFS-32)
+#define STACK_SLOT_IAMR (SFS-40)
+#define STACK_SLOT_CIABR (SFS-48)
+#define STACK_SLOT_DAWR (SFS-56)
+#define STACK_SLOT_DAWRX (SFS-64)
+
/*
* Call kvmppc_hv_entry in real mode.
* Must be called with interrupts hard-disabled.
@@ -214,6 +231,8 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
kvmppc_primary_no_guest:
/* We handle this much like a ceded vcpu */
/* put the HDEC into the DEC, since HDEC interrupts don't wake us */
+ /* HDEC may be larger than DEC for arch >= v3.00, but since the */
+ /* HDEC value came from DEC in the first place, it will fit */
mfspr r3, SPRN_HDEC
mtspr SPRN_DEC, r3
/*
@@ -295,8 +314,9 @@ kvm_novcpu_wakeup:
/* See if our timeslice has expired (HDEC is negative) */
mfspr r0, SPRN_HDEC
+ EXTEND_HDEC(r0)
li r12, BOOK3S_INTERRUPT_HV_DECREMENTER
- cmpwi r0, 0
+ cmpdi r0, 0
blt kvm_novcpu_exit
/* Got an IPI but other vcpus aren't yet exiting, must be a latecomer */
@@ -319,10 +339,10 @@ kvm_novcpu_exit:
bl kvmhv_accumulate_time
#endif
13: mr r3, r12
- stw r12, 112-4(r1)
+ stw r12, STACK_SLOT_TRAP(r1)
bl kvmhv_commence_exit
nop
- lwz r12, 112-4(r1)
+ lwz r12, STACK_SLOT_TRAP(r1)
b kvmhv_switch_to_host
/*
@@ -390,8 +410,8 @@ kvm_secondary_got_guest:
lbz r4, HSTATE_PTID(r13)
cmpwi r4, 0
bne 63f
- lis r6, 0x7fff
- ori r6, r6, 0xffff
+ LOAD_REG_ADDR(r6, decrementer_max)
+ ld r6, 0(r6)
mtspr SPRN_HDEC, r6
/* and set per-LPAR registers, if doing dynamic micro-threading */
ld r6, HSTATE_SPLIT_MODE(r13)
@@ -545,11 +565,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
* *
*****************************************************************************/
-/* Stack frame offsets */
-#define STACK_SLOT_TID (112-16)
-#define STACK_SLOT_PSSCR (112-24)
-#define STACK_SLOT_PID (112-32)
-
.global kvmppc_hv_entry
kvmppc_hv_entry:
@@ -565,7 +580,7 @@ kvmppc_hv_entry:
*/
mflr r0
std r0, PPC_LR_STKOFF(r1)
- stdu r1, -112(r1)
+ stdu r1, -SFS(r1)
/* Save R1 in the PACA */
std r1, HSTATE_HOST_R1(r13)
@@ -749,10 +764,20 @@ BEGIN_FTR_SECTION
mfspr r5, SPRN_TIDR
mfspr r6, SPRN_PSSCR
mfspr r7, SPRN_PID
+ mfspr r8, SPRN_IAMR
std r5, STACK_SLOT_TID(r1)
std r6, STACK_SLOT_PSSCR(r1)
std r7, STACK_SLOT_PID(r1)
+ std r8, STACK_SLOT_IAMR(r1)
END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
+BEGIN_FTR_SECTION
+ mfspr r5, SPRN_CIABR
+ mfspr r6, SPRN_DAWR
+ mfspr r7, SPRN_DAWRX
+ std r5, STACK_SLOT_CIABR(r1)
+ std r6, STACK_SLOT_DAWR(r1)
+ std r7, STACK_SLOT_DAWRX(r1)
+END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
BEGIN_FTR_SECTION
/* Set partition DABR */
@@ -968,7 +993,8 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_300)
/* Check if HDEC expires soon */
mfspr r3, SPRN_HDEC
- cmpwi r3, 512 /* 1 microsecond */
+ EXTEND_HDEC(r3)
+ cmpdi r3, 512 /* 1 microsecond */
blt hdec_soon
#ifdef CONFIG_KVM_XICS
@@ -1505,11 +1531,10 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_ARCH_300)
* set by the guest could disrupt the host.
*/
li r0, 0
- mtspr SPRN_IAMR, r0
- mtspr SPRN_CIABR, r0
- mtspr SPRN_DAWRX, r0
+ mtspr SPRN_PSPB, r0
mtspr SPRN_WORT, r0
BEGIN_FTR_SECTION
+ mtspr SPRN_IAMR, r0
mtspr SPRN_TCSCR, r0
/* Set MMCRS to 1<<31 to freeze and disable the SPMC counters */
li r0, 1
@@ -1525,6 +1550,7 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_300)
std r6,VCPU_UAMOR(r9)
li r6,0
mtspr SPRN_AMR,r6
+ mtspr SPRN_UAMOR, r6
/* Switch DSCR back to host value */
mfspr r8, SPRN_DSCR
@@ -1670,12 +1696,22 @@ END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
/* Restore host values of some registers */
BEGIN_FTR_SECTION
+ ld r5, STACK_SLOT_CIABR(r1)
+ ld r6, STACK_SLOT_DAWR(r1)
+ ld r7, STACK_SLOT_DAWRX(r1)
+ mtspr SPRN_CIABR, r5
+ mtspr SPRN_DAWR, r6
+ mtspr SPRN_DAWRX, r7
+END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
+BEGIN_FTR_SECTION
ld r5, STACK_SLOT_TID(r1)
ld r6, STACK_SLOT_PSSCR(r1)
ld r7, STACK_SLOT_PID(r1)
+ ld r8, STACK_SLOT_IAMR(r1)
mtspr SPRN_TIDR, r5
mtspr SPRN_PSSCR, r6
mtspr SPRN_PID, r7
+ mtspr SPRN_IAMR, r8
END_FTR_SECTION_IFSET(CPU_FTR_ARCH_300)
BEGIN_FTR_SECTION
PPC_INVALIDATE_ERAT
@@ -1819,8 +1855,8 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_TYPE_RADIX)
li r0, KVM_GUEST_MODE_NONE
stb r0, HSTATE_IN_GUEST(r13)
- ld r0, 112+PPC_LR_STKOFF(r1)
- addi r1, r1, 112
+ ld r0, SFS+PPC_LR_STKOFF(r1)
+ addi r1, r1, SFS
mtlr r0
blr
@@ -2366,12 +2402,13 @@ END_FTR_SECTION_IFSET(CPU_FTR_TM)
mfspr r3, SPRN_DEC
mfspr r4, SPRN_HDEC
mftb r5
- cmpw r3, r4
+ extsw r3, r3
+ EXTEND_HDEC(r4)
+ cmpd r3, r4
ble 67f
mtspr SPRN_DEC, r4
67:
/* save expiry time of guest decrementer */
- extsw r3, r3
add r3, r3, r5
ld r4, HSTATE_KVM_VCPU(r13)
ld r5, HSTATE_KVM_VCORE(r13)
diff --git a/arch/s390/kvm/gaccess.c b/arch/s390/kvm/gaccess.c
index 9da243d94cc3..3b297fa3aa67 100644
--- a/arch/s390/kvm/gaccess.c
+++ b/arch/s390/kvm/gaccess.c
@@ -977,11 +977,12 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr,
ptr = asce.origin * 4096;
if (asce.r) {
*fake = 1;
+ ptr = 0;
asce.dt = ASCE_TYPE_REGION1;
}
switch (asce.dt) {
case ASCE_TYPE_REGION1:
- if (vaddr.rfx01 > asce.tl && !asce.r)
+ if (vaddr.rfx01 > asce.tl && !*fake)
return PGM_REGION_FIRST_TRANS;
break;
case ASCE_TYPE_REGION2:
@@ -1009,8 +1010,7 @@ static int kvm_s390_shadow_tables(struct gmap *sg, unsigned long saddr,
union region1_table_entry rfte;
if (*fake) {
- /* offset in 16EB guest memory block */
- ptr = ptr + ((unsigned long) vaddr.rsx << 53UL);
+ ptr += (unsigned long) vaddr.rfx << 53;
rfte.val = ptr;
goto shadow_r2t;
}
@@ -1036,8 +1036,7 @@ shadow_r2t:
union region2_table_entry rste;
if (*fake) {
- /* offset in 8PB guest memory block */
- ptr = ptr + ((unsigned long) vaddr.rtx << 42UL);
+ ptr += (unsigned long) vaddr.rsx << 42;
rste.val = ptr;
goto shadow_r3t;
}
@@ -1064,8 +1063,7 @@ shadow_r3t:
union region3_table_entry rtte;
if (*fake) {
- /* offset in 4TB guest memory block */
- ptr = ptr + ((unsigned long) vaddr.sx << 31UL);
+ ptr += (unsigned long) vaddr.rtx << 31;
rtte.val = ptr;
goto shadow_sgt;
}
@@ -1101,8 +1099,7 @@ shadow_sgt:
union segment_table_entry ste;
if (*fake) {
- /* offset in 2G guest memory block */
- ptr = ptr + ((unsigned long) vaddr.sx << 20UL);
+ ptr += (unsigned long) vaddr.sx << 20;
ste.val = ptr;
goto shadow_pgt;
}
diff --git a/arch/x86/include/asm/kvm_emulate.h b/arch/x86/include/asm/kvm_emulate.h
index 055962615779..722d0e568863 100644
--- a/arch/x86/include/asm/kvm_emulate.h
+++ b/arch/x86/include/asm/kvm_emulate.h
@@ -296,6 +296,7 @@ struct x86_emulate_ctxt {
bool perm_ok; /* do not check permissions if true */
bool ud; /* inject an #UD if host doesn't support insn */
+ bool tf; /* TF value before instruction (after for syscall/sysret) */
bool have_exception;
struct x86_exception exception;
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 0816ab2e8adc..80890dee66ce 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -2742,6 +2742,7 @@ static int em_syscall(struct x86_emulate_ctxt *ctxt)
ctxt->eflags &= ~(X86_EFLAGS_VM | X86_EFLAGS_IF);
}
+ ctxt->tf = (ctxt->eflags & X86_EFLAGS_TF) != 0;
return X86EMUL_CONTINUE;
}
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 87d3cb901935..0e846f0cb83b 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -5313,6 +5313,8 @@ static void init_emulate_ctxt(struct kvm_vcpu *vcpu)
kvm_x86_ops->get_cs_db_l_bits(vcpu, &cs_db, &cs_l);
ctxt->eflags = kvm_get_rflags(vcpu);
+ ctxt->tf = (ctxt->eflags & X86_EFLAGS_TF) != 0;
+
ctxt->eip = kvm_rip_read(vcpu);
ctxt->mode = (!is_protmode(vcpu)) ? X86EMUL_MODE_REAL :
(ctxt->eflags & X86_EFLAGS_VM) ? X86EMUL_MODE_VM86 :
@@ -5528,36 +5530,25 @@ static int kvm_vcpu_check_hw_bp(unsigned long addr, u32 type, u32 dr7,
return dr6;
}
-static void kvm_vcpu_check_singlestep(struct kvm_vcpu *vcpu, unsigned long rflags, int *r)
+static void kvm_vcpu_do_singlestep(struct kvm_vcpu *vcpu, int *r)
{
struct kvm_run *kvm_run = vcpu->run;
- /*
- * rflags is the old, "raw" value of the flags. The new value has
- * not been saved yet.
- *
- * This is correct even for TF set by the guest, because "the
- * processor will not generate this exception after the instruction
- * that sets the TF flag".
- */
- if (unlikely(rflags & X86_EFLAGS_TF)) {
- if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP) {
- kvm_run->debug.arch.dr6 = DR6_BS | DR6_FIXED_1 |
- DR6_RTM;
- kvm_run->debug.arch.pc = vcpu->arch.singlestep_rip;
- kvm_run->debug.arch.exception = DB_VECTOR;
- kvm_run->exit_reason = KVM_EXIT_DEBUG;
- *r = EMULATE_USER_EXIT;
- } else {
- /*
- * "Certain debug exceptions may clear bit 0-3. The
- * remaining contents of the DR6 register are never
- * cleared by the processor".
- */
- vcpu->arch.dr6 &= ~15;
- vcpu->arch.dr6 |= DR6_BS | DR6_RTM;
- kvm_queue_exception(vcpu, DB_VECTOR);
- }
+ if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP) {
+ kvm_run->debug.arch.dr6 = DR6_BS | DR6_FIXED_1 | DR6_RTM;
+ kvm_run->debug.arch.pc = vcpu->arch.singlestep_rip;
+ kvm_run->debug.arch.exception = DB_VECTOR;
+ kvm_run->exit_reason = KVM_EXIT_DEBUG;
+ *r = EMULATE_USER_EXIT;
+ } else {
+ /*
+ * "Certain debug exceptions may clear bit 0-3. The
+ * remaining contents of the DR6 register are never
+ * cleared by the processor".
+ */
+ vcpu->arch.dr6 &= ~15;
+ vcpu->arch.dr6 |= DR6_BS | DR6_RTM;
+ kvm_queue_exception(vcpu, DB_VECTOR);
}
}
@@ -5567,7 +5558,17 @@ int kvm_skip_emulated_instruction(struct kvm_vcpu *vcpu)
int r = EMULATE_DONE;
kvm_x86_ops->skip_emulated_instruction(vcpu);
- kvm_vcpu_check_singlestep(vcpu, rflags, &r);
+
+ /*
+ * rflags is the old, "raw" value of the flags. The new value has
+ * not been saved yet.
+ *
+ * This is correct even for TF set by the guest, because "the
+ * processor will not generate this exception after the instruction
+ * that sets the TF flag".
+ */
+ if (unlikely(rflags & X86_EFLAGS_TF))
+ kvm_vcpu_do_singlestep(vcpu, &r);
return r == EMULATE_DONE;
}
EXPORT_SYMBOL_GPL(kvm_skip_emulated_instruction);
@@ -5726,8 +5727,9 @@ restart:
toggle_interruptibility(vcpu, ctxt->interruptibility);
vcpu->arch.emulate_regs_need_sync_to_vcpu = false;
kvm_rip_write(vcpu, ctxt->eip);
- if (r == EMULATE_DONE)
- kvm_vcpu_check_singlestep(vcpu, rflags, &r);
+ if (r == EMULATE_DONE &&
+ (ctxt->tf || (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP)))
+ kvm_vcpu_do_singlestep(vcpu, &r);
if (!ctxt->have_exception ||
exception_type(ctxt->exception.vector) == EXCPT_TRAP)
__kvm_set_rflags(vcpu, ctxt->eflags);