From: Avi Kivity <avi@redhat.com>
To: linux-kernel@vger.kernel.org
Cc: kvm@vger.kernel.org
Subject: [PATCH 36/42] KVM: x86: Rework guest single-step flag injection and filtering
Date: Mon, 16 Nov 2009 14:19:37 +0200 [thread overview]
Message-ID: <1258373983-8693-37-git-send-email-avi@redhat.com> (raw)
In-Reply-To: <1258373983-8693-1-git-send-email-avi@redhat.com>
From: Jan Kiszka <jan.kiszka@siemens.com>
Push TF and RF injection and filtering on guest single-stepping into the
vender get/set_rflags callbacks. This makes the whole mechanism more
robust wrt user space IOCTL order and instruction emulations.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
---
arch/x86/include/asm/kvm_host.h | 3 ++
arch/x86/kvm/x86.c | 77 +++++++++++++++++++++++----------------
2 files changed, 48 insertions(+), 32 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index e7f8708..179a919 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -614,6 +614,9 @@ void kvm_get_cs_db_l_bits(struct kvm_vcpu *vcpu, int *db, int *l);
int kvm_get_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata);
int kvm_set_msr_common(struct kvm_vcpu *vcpu, u32 msr, u64 data);
+unsigned long kvm_get_rflags(struct kvm_vcpu *vcpu);
+void kvm_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags);
+
void kvm_queue_exception(struct kvm_vcpu *vcpu, unsigned nr);
void kvm_queue_exception_e(struct kvm_vcpu *vcpu, unsigned nr, u32 error_code);
void kvm_inject_page_fault(struct kvm_vcpu *vcpu, unsigned long cr2,
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 4693f91..385cd0a 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -235,6 +235,25 @@ bool kvm_require_cpl(struct kvm_vcpu *vcpu, int required_cpl)
}
EXPORT_SYMBOL_GPL(kvm_require_cpl);
+unsigned long kvm_get_rflags(struct kvm_vcpu *vcpu)
+{
+ unsigned long rflags;
+
+ rflags = kvm_x86_ops->get_rflags(vcpu);
+ if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP)
+ rflags &= ~(unsigned long)(X86_EFLAGS_TF | X86_EFLAGS_RF);
+ return rflags;
+}
+EXPORT_SYMBOL_GPL(kvm_get_rflags);
+
+void kvm_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags)
+{
+ if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP)
+ rflags |= X86_EFLAGS_TF | X86_EFLAGS_RF;
+ kvm_x86_ops->set_rflags(vcpu, rflags);
+}
+EXPORT_SYMBOL_GPL(kvm_set_rflags);
+
/*
* Load the pae pdptrs. Return true is they are all valid.
*/
@@ -2777,7 +2796,7 @@ int emulate_instruction(struct kvm_vcpu *vcpu,
kvm_x86_ops->get_cs_db_l_bits(vcpu, &cs_db, &cs_l);
vcpu->arch.emulate_ctxt.vcpu = vcpu;
- vcpu->arch.emulate_ctxt.eflags = kvm_x86_ops->get_rflags(vcpu);
+ vcpu->arch.emulate_ctxt.eflags = kvm_get_rflags(vcpu);
vcpu->arch.emulate_ctxt.mode =
(vcpu->arch.emulate_ctxt.eflags & X86_EFLAGS_VM)
? X86EMUL_MODE_REAL : cs_l
@@ -2855,7 +2874,7 @@ int emulate_instruction(struct kvm_vcpu *vcpu,
return EMULATE_DO_MMIO;
}
- kvm_x86_ops->set_rflags(vcpu, vcpu->arch.emulate_ctxt.eflags);
+ kvm_set_rflags(vcpu, vcpu->arch.emulate_ctxt.eflags);
if (vcpu->mmio_is_write) {
vcpu->mmio_needed = 0;
@@ -3291,7 +3310,7 @@ void realmode_lmsw(struct kvm_vcpu *vcpu, unsigned long msw,
unsigned long *rflags)
{
kvm_lmsw(vcpu, msw);
- *rflags = kvm_x86_ops->get_rflags(vcpu);
+ *rflags = kvm_get_rflags(vcpu);
}
unsigned long realmode_get_cr(struct kvm_vcpu *vcpu, int cr)
@@ -3329,7 +3348,7 @@ void realmode_set_cr(struct kvm_vcpu *vcpu, int cr, unsigned long val,
switch (cr) {
case 0:
kvm_set_cr0(vcpu, mk_cr_64(vcpu->arch.cr0, val));
- *rflags = kvm_x86_ops->get_rflags(vcpu);
+ *rflags = kvm_get_rflags(vcpu);
break;
case 2:
vcpu->arch.cr2 = val;
@@ -3460,7 +3479,7 @@ static void post_kvm_run_save(struct kvm_vcpu *vcpu)
{
struct kvm_run *kvm_run = vcpu->run;
- kvm_run->if_flag = (kvm_x86_ops->get_rflags(vcpu) & X86_EFLAGS_IF) != 0;
+ kvm_run->if_flag = (kvm_get_rflags(vcpu) & X86_EFLAGS_IF) != 0;
kvm_run->cr8 = kvm_get_cr8(vcpu);
kvm_run->apic_base = kvm_get_apic_base(vcpu);
if (irqchip_in_kernel(vcpu->kvm))
@@ -3840,13 +3859,7 @@ int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
#endif
regs->rip = kvm_rip_read(vcpu);
- regs->rflags = kvm_x86_ops->get_rflags(vcpu);
-
- /*
- * Don't leak debug flags in case they were set for guest debugging
- */
- if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP)
- regs->rflags &= ~(X86_EFLAGS_TF | X86_EFLAGS_RF);
+ regs->rflags = kvm_get_rflags(vcpu);
vcpu_put(vcpu);
@@ -3874,12 +3887,10 @@ int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
kvm_register_write(vcpu, VCPU_REGS_R13, regs->r13);
kvm_register_write(vcpu, VCPU_REGS_R14, regs->r14);
kvm_register_write(vcpu, VCPU_REGS_R15, regs->r15);
-
#endif
kvm_rip_write(vcpu, regs->rip);
- kvm_x86_ops->set_rflags(vcpu, regs->rflags);
-
+ kvm_set_rflags(vcpu, regs->rflags);
vcpu->arch.exception.pending = false;
@@ -4098,7 +4109,7 @@ static int is_vm86_segment(struct kvm_vcpu *vcpu, int seg)
{
return (seg != VCPU_SREG_LDTR) &&
(seg != VCPU_SREG_TR) &&
- (kvm_x86_ops->get_rflags(vcpu) & X86_EFLAGS_VM);
+ (kvm_get_rflags(vcpu) & X86_EFLAGS_VM);
}
int kvm_load_segment_descriptor(struct kvm_vcpu *vcpu, u16 selector,
@@ -4126,7 +4137,7 @@ static void save_state_to_tss32(struct kvm_vcpu *vcpu,
{
tss->cr3 = vcpu->arch.cr3;
tss->eip = kvm_rip_read(vcpu);
- tss->eflags = kvm_x86_ops->get_rflags(vcpu);
+ tss->eflags = kvm_get_rflags(vcpu);
tss->eax = kvm_register_read(vcpu, VCPU_REGS_RAX);
tss->ecx = kvm_register_read(vcpu, VCPU_REGS_RCX);
tss->edx = kvm_register_read(vcpu, VCPU_REGS_RDX);
@@ -4150,7 +4161,7 @@ static int load_state_from_tss32(struct kvm_vcpu *vcpu,
kvm_set_cr3(vcpu, tss->cr3);
kvm_rip_write(vcpu, tss->eip);
- kvm_x86_ops->set_rflags(vcpu, tss->eflags | 2);
+ kvm_set_rflags(vcpu, tss->eflags | 2);
kvm_register_write(vcpu, VCPU_REGS_RAX, tss->eax);
kvm_register_write(vcpu, VCPU_REGS_RCX, tss->ecx);
@@ -4188,7 +4199,7 @@ static void save_state_to_tss16(struct kvm_vcpu *vcpu,
struct tss_segment_16 *tss)
{
tss->ip = kvm_rip_read(vcpu);
- tss->flag = kvm_x86_ops->get_rflags(vcpu);
+ tss->flag = kvm_get_rflags(vcpu);
tss->ax = kvm_register_read(vcpu, VCPU_REGS_RAX);
tss->cx = kvm_register_read(vcpu, VCPU_REGS_RCX);
tss->dx = kvm_register_read(vcpu, VCPU_REGS_RDX);
@@ -4209,7 +4220,7 @@ static int load_state_from_tss16(struct kvm_vcpu *vcpu,
struct tss_segment_16 *tss)
{
kvm_rip_write(vcpu, tss->ip);
- kvm_x86_ops->set_rflags(vcpu, tss->flag | 2);
+ kvm_set_rflags(vcpu, tss->flag | 2);
kvm_register_write(vcpu, VCPU_REGS_RAX, tss->ax);
kvm_register_write(vcpu, VCPU_REGS_RCX, tss->cx);
kvm_register_write(vcpu, VCPU_REGS_RDX, tss->dx);
@@ -4355,8 +4366,8 @@ int kvm_task_switch(struct kvm_vcpu *vcpu, u16 tss_selector, int reason)
}
if (reason == TASK_SWITCH_IRET) {
- u32 eflags = kvm_x86_ops->get_rflags(vcpu);
- kvm_x86_ops->set_rflags(vcpu, eflags & ~X86_EFLAGS_NT);
+ u32 eflags = kvm_get_rflags(vcpu);
+ kvm_set_rflags(vcpu, eflags & ~X86_EFLAGS_NT);
}
/* set back link to prev task only if NT bit is set in eflags
@@ -4377,8 +4388,8 @@ int kvm_task_switch(struct kvm_vcpu *vcpu, u16 tss_selector, int reason)
old_tss_base, &nseg_desc);
if (reason == TASK_SWITCH_CALL || reason == TASK_SWITCH_GATE) {
- u32 eflags = kvm_x86_ops->get_rflags(vcpu);
- kvm_x86_ops->set_rflags(vcpu, eflags | X86_EFLAGS_NT);
+ u32 eflags = kvm_get_rflags(vcpu);
+ kvm_set_rflags(vcpu, eflags | X86_EFLAGS_NT);
}
if (reason != TASK_SWITCH_IRET) {
@@ -4473,12 +4484,15 @@ int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
struct kvm_guest_debug *dbg)
{
unsigned long rflags;
- int old_debug;
int i;
vcpu_load(vcpu);
- old_debug = vcpu->guest_debug;
+ /*
+ * Read rflags as long as potentially injected trace flags are still
+ * filtered out.
+ */
+ rflags = kvm_get_rflags(vcpu);
vcpu->guest_debug = dbg->control;
if (!(vcpu->guest_debug & KVM_GUESTDBG_ENABLE))
@@ -4495,12 +4509,11 @@ int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
vcpu->arch.switch_db_regs = (vcpu->arch.dr7 & DR7_BP_EN_MASK);
}
- rflags = kvm_x86_ops->get_rflags(vcpu);
- if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP)
- rflags |= X86_EFLAGS_TF | X86_EFLAGS_RF;
- else if (old_debug & KVM_GUESTDBG_SINGLESTEP)
- rflags &= ~(X86_EFLAGS_TF | X86_EFLAGS_RF);
- kvm_x86_ops->set_rflags(vcpu, rflags);
+ /*
+ * Trigger an rflags update that will inject or remove the trace
+ * flags.
+ */
+ kvm_set_rflags(vcpu, rflags);
kvm_x86_ops->set_guest_debug(vcpu, dbg);
--
1.6.5.2
next prev parent reply other threads:[~2009-11-16 12:19 UTC|newest]
Thread overview: 56+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-11-16 12:19 [PATCH 00/42] KVM updates for the 2.6.33 merge window (batch 1/2) Avi Kivity
2009-11-16 12:19 ` [PATCH 01/42] core, x86: Add user return notifiers Avi Kivity
2009-11-16 12:19 ` [PATCH 02/42] x86: Fix user return notifier build Avi Kivity
2009-11-16 12:19 ` [PATCH 03/42] x86: Fix user return notifier put_cpu_var() invocation Avi Kivity
2009-11-16 12:19 ` [PATCH 04/42] KVM: Don't wrap schedule() with vcpu_put()/vcpu_load() Avi Kivity
2009-11-16 12:19 ` [PATCH 05/42] KVM: x86 emulator: Add 'push/pop sreg' instructions Avi Kivity
2009-11-16 12:19 ` [PATCH 06/42] KVM: x86 emulator: Introduce No64 decode option Avi Kivity
2009-11-16 12:19 ` [PATCH 07/42] KVM: Don't pass kvm_run arguments Avi Kivity
2009-11-16 12:19 ` [PATCH 08/42] KVM: Call pic_clear_isr() on pic reset to reuse logic there Avi Kivity
2009-11-16 12:19 ` [PATCH 09/42] KVM: Move irq sharing information to irqchip level Avi Kivity
2009-11-16 12:19 ` [PATCH 10/42] KVM: Change irq routing table to use gsi indexed array Avi Kivity
2009-11-16 12:19 ` [PATCH 11/42] KVM: Maintain back mapping from irqchip/pin to gsi Avi Kivity
2009-11-16 12:19 ` [PATCH 12/42] KVM: Move irq routing data structure to rcu locking Avi Kivity
2009-11-16 12:19 ` [PATCH 13/42] KVM: Move irq ack notifier list to arch independent code Avi Kivity
2009-11-16 12:19 ` [PATCH 14/42] KVM: Convert irq notifiers lists to RCU locking Avi Kivity
2009-11-16 12:19 ` [PATCH 15/42] KVM: Move IO APIC to its own lock Avi Kivity
2009-11-16 12:19 ` [PATCH 16/42] KVM: Drop kvm->irq_lock lock from irq injection path Avi Kivity
2009-11-16 12:19 ` [PATCH 17/42] KVM: Return -ENOTTY on unrecognized ioctls Avi Kivity
2009-11-16 12:19 ` [PATCH 18/42] KVM: Move assigned device code to own file Avi Kivity
2009-11-16 12:19 ` [PATCH 19/42] KVM: x86 emulator: Add missing decoder flags for 'or' instructions Avi Kivity
2009-11-16 12:19 ` [PATCH 20/42] KVM: x86 emulator: Add pusha and popa instructions Avi Kivity
2009-11-16 12:19 ` [PATCH 21/42] KVM: VMX: Enhance invalid guest state emulation Avi Kivity
2009-11-16 12:19 ` [PATCH 22/42] KVM: SVM: remove needless mmap_sem acquision from nested_svm_map Avi Kivity
2009-11-16 12:19 ` [PATCH 23/42] KVM: Activate Virtualization On Demand Avi Kivity
2010-03-17 21:57 ` Dieter Ries
2010-03-17 22:02 ` Alexander Graf
2010-03-17 22:40 ` Dieter Ries
2010-03-17 22:47 ` Alexander Graf
2010-03-18 7:11 ` Dieter Ries
2010-03-18 7:17 ` Alexander Graf
2010-03-19 2:26 ` Dieter Ries
2010-08-08 12:02 ` Serge Belyshev
2010-08-16 13:24 ` Alexander Graf
2010-08-16 13:49 ` Serge Belyshev
2010-08-16 14:13 ` Alexander Graf
2010-03-18 5:41 ` Michael Tokarev
2010-03-18 7:04 ` Dieter Ries
2009-11-16 12:19 ` [PATCH 24/42] KVM: remove duplicated #include Avi Kivity
2009-11-16 12:19 ` [PATCH 25/42] KVM: SVM: reorganize svm_interrupt_allowed Avi Kivity
2009-11-16 12:19 ` [PATCH 26/42] KVM: SVM: don't copy exit_int_info on nested vmrun Avi Kivity
2009-11-16 12:19 ` [PATCH 27/42] KVM: SVM: Remove remaining occurences of rdtscll Avi Kivity
2009-11-16 12:19 ` [PATCH 28/42] KVM: fix lock imbalance in kvm_*_irq_source_id() Avi Kivity
2009-11-16 12:19 ` [PATCH 29/42] KVM: Separate timer intialization into an indepedent function Avi Kivity
2009-11-16 12:19 ` [PATCH 30/42] KVM: Kill the confusing tsc_ref_khz and ref_freq variables Avi Kivity
2009-11-16 12:19 ` [PATCH 31/42] KVM: Fix printk name error in svm.c Avi Kivity
2009-11-16 12:19 ` [PATCH 32/42] KVM: Fix hotplug of CPUs Avi Kivity
2009-11-16 12:19 ` [PATCH 33/42] KVM: remove pre_task_link setting in save_state_to_tss16 Avi Kivity
2009-11-16 12:19 ` [PATCH 34/42] KVM: x86: Refactor guest debug IOCTL handling Avi Kivity
2009-11-16 12:19 ` [PATCH 35/42] KVM: x86: disable paravirt mmu reporting Avi Kivity
2009-11-16 12:19 ` Avi Kivity [this message]
2009-11-16 12:19 ` [PATCH 37/42] KVM: x86: include pvclock MSRs in msrs_to_save Avi Kivity
2009-11-16 12:19 ` [PATCH 38/42] KVM: SVM: Notify nested hypervisor of lost event injections Avi Kivity
2009-11-16 12:19 ` [PATCH 39/42] KVM: SVM: Move INTR vmexit out of atomic code Avi Kivity
2009-11-16 12:19 ` [PATCH 40/42] KVM: SVM: Add tracepoint for nested vmrun Avi Kivity
2009-11-16 12:19 ` [PATCH 41/42] KVM: SVM: Add tracepoint for nested #vmexit Avi Kivity
2009-11-16 12:19 ` [PATCH 42/42] KVM: SVM: Add tracepoint for injected #vmexit Avi Kivity
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