From: Marc Zyngier <marc.zyngier@arm.com>
To: "Paolo Bonzini" <pbonzini@redhat.com>,
"Radim Krčmář" <rkrcmar@redhat.com>
Cc: Punit Agrawal <punit.agrawal@arm.com>,
kvm@vger.kernel.org,
"Gustavo A . R . Silva" <gustavo@embeddedor.com>,
Will Deacon <will.deacon@arm.com>,
linux-arm-kernel@lists.infradead.org,
kvmarm@lists.cs.columbia.edu, Lukas Braun <koomi@moshbit.net>
Subject: [PATCH 02/28] arm64: KVM: Consistently advance singlestep when emulating instructions
Date: Wed, 19 Dec 2018 18:03:23 +0000 [thread overview]
Message-ID: <20181219180349.242681-3-marc.zyngier@arm.com> (raw)
In-Reply-To: <20181219180349.242681-1-marc.zyngier@arm.com>
From: Mark Rutland <mark.rutland@arm.com>
When we emulate a guest instruction, we don't advance the hardware
singlestep state machine, and thus the guest will receive a software
step exception after a next instruction which is not emulated by the
host.
We bodge around this in an ad-hoc fashion. Sometimes we explicitly check
whether userspace requested a single step, and fake a debug exception
from within the kernel. Other times, we advance the HW singlestep state
rely on the HW to generate the exception for us. Thus, the observed step
behaviour differs for host and guest.
Let's make this simpler and consistent by always advancing the HW
singlestep state machine when we skip an instruction. Thus we can rely
on the hardware to generate the singlestep exception for us, and never
need to explicitly check for an active-pending step, nor do we need to
fake a debug exception from the guest.
Cc: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
arch/arm/include/asm/kvm_host.h | 5 ---
arch/arm64/include/asm/kvm_emulate.h | 35 ++++++++++++++-----
arch/arm64/include/asm/kvm_host.h | 1 -
arch/arm64/kvm/debug.c | 21 ------------
arch/arm64/kvm/handle_exit.c | 14 +-------
arch/arm64/kvm/hyp/switch.c | 43 +++---------------------
arch/arm64/kvm/hyp/vgic-v2-cpuif-proxy.c | 12 +++++--
virt/kvm/arm/arm.c | 2 --
virt/kvm/arm/hyp/vgic-v3-sr.c | 6 +++-
9 files changed, 46 insertions(+), 93 deletions(-)
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
index 5ca5d9af0c26..c5634c6ffcea 100644
--- a/arch/arm/include/asm/kvm_host.h
+++ b/arch/arm/include/asm/kvm_host.h
@@ -296,11 +296,6 @@ static inline void kvm_arm_init_debug(void) {}
static inline void kvm_arm_setup_debug(struct kvm_vcpu *vcpu) {}
static inline void kvm_arm_clear_debug(struct kvm_vcpu *vcpu) {}
static inline void kvm_arm_reset_debug_ptr(struct kvm_vcpu *vcpu) {}
-static inline bool kvm_arm_handle_step_debug(struct kvm_vcpu *vcpu,
- struct kvm_run *run)
-{
- return false;
-}
int kvm_arm_vcpu_arch_set_attr(struct kvm_vcpu *vcpu,
struct kvm_device_attr *attr);
diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h
index 21247870def7..506386a3edde 100644
--- a/arch/arm64/include/asm/kvm_emulate.h
+++ b/arch/arm64/include/asm/kvm_emulate.h
@@ -24,6 +24,7 @@
#include <linux/kvm_host.h>
+#include <asm/debug-monitors.h>
#include <asm/esr.h>
#include <asm/kvm_arm.h>
#include <asm/kvm_hyp.h>
@@ -147,14 +148,6 @@ static inline bool kvm_condition_valid(const struct kvm_vcpu *vcpu)
return true;
}
-static inline void kvm_skip_instr(struct kvm_vcpu *vcpu, bool is_wide_instr)
-{
- if (vcpu_mode_is_32bit(vcpu))
- kvm_skip_instr32(vcpu, is_wide_instr);
- else
- *vcpu_pc(vcpu) += 4;
-}
-
static inline void vcpu_set_thumb(struct kvm_vcpu *vcpu)
{
*vcpu_cpsr(vcpu) |= PSR_AA32_T_BIT;
@@ -424,4 +417,30 @@ static inline unsigned long vcpu_data_host_to_guest(struct kvm_vcpu *vcpu,
return data; /* Leave LE untouched */
}
+static inline void kvm_skip_instr(struct kvm_vcpu *vcpu, bool is_wide_instr)
+{
+ if (vcpu_mode_is_32bit(vcpu))
+ kvm_skip_instr32(vcpu, is_wide_instr);
+ else
+ *vcpu_pc(vcpu) += 4;
+
+ /* advance the singlestep state machine */
+ *vcpu_cpsr(vcpu) &= ~DBG_SPSR_SS;
+}
+
+/*
+ * Skip an instruction which has been emulated at hyp while most guest sysregs
+ * are live.
+ */
+static inline void __hyp_text __kvm_skip_instr(struct kvm_vcpu *vcpu)
+{
+ *vcpu_pc(vcpu) = read_sysreg_el2(elr);
+ vcpu->arch.ctxt.gp_regs.regs.pstate = read_sysreg_el2(spsr);
+
+ kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
+
+ write_sysreg_el2(vcpu->arch.ctxt.gp_regs.regs.pstate, spsr);
+ write_sysreg_el2(*vcpu_pc(vcpu), elr);
+}
+
#endif /* __ARM64_KVM_EMULATE_H__ */
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 52fbc823ff8c..7a5035f9c5c3 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -445,7 +445,6 @@ void kvm_arm_init_debug(void);
void kvm_arm_setup_debug(struct kvm_vcpu *vcpu);
void kvm_arm_clear_debug(struct kvm_vcpu *vcpu);
void kvm_arm_reset_debug_ptr(struct kvm_vcpu *vcpu);
-bool kvm_arm_handle_step_debug(struct kvm_vcpu *vcpu, struct kvm_run *run);
int kvm_arm_vcpu_arch_set_attr(struct kvm_vcpu *vcpu,
struct kvm_device_attr *attr);
int kvm_arm_vcpu_arch_get_attr(struct kvm_vcpu *vcpu,
diff --git a/arch/arm64/kvm/debug.c b/arch/arm64/kvm/debug.c
index 00d422336a45..f39801e4136c 100644
--- a/arch/arm64/kvm/debug.c
+++ b/arch/arm64/kvm/debug.c
@@ -236,24 +236,3 @@ void kvm_arm_clear_debug(struct kvm_vcpu *vcpu)
}
}
}
-
-
-/*
- * After successfully emulating an instruction, we might want to
- * return to user space with a KVM_EXIT_DEBUG. We can only do this
- * once the emulation is complete, though, so for userspace emulations
- * we have to wait until we have re-entered KVM before calling this
- * helper.
- *
- * Return true (and set exit_reason) to return to userspace or false
- * if no further action is required.
- */
-bool kvm_arm_handle_step_debug(struct kvm_vcpu *vcpu, struct kvm_run *run)
-{
- if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP) {
- run->exit_reason = KVM_EXIT_DEBUG;
- run->debug.arch.hsr = ESR_ELx_EC_SOFTSTP_LOW << ESR_ELx_EC_SHIFT;
- return true;
- }
- return false;
-}
diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c
index 35a81bebd02b..b0643f9c4873 100644
--- a/arch/arm64/kvm/handle_exit.c
+++ b/arch/arm64/kvm/handle_exit.c
@@ -229,13 +229,6 @@ static int handle_trap_exceptions(struct kvm_vcpu *vcpu, struct kvm_run *run)
handled = exit_handler(vcpu, run);
}
- /*
- * kvm_arm_handle_step_debug() sets the exit_reason on the kvm_run
- * structure if we need to return to userspace.
- */
- if (handled > 0 && kvm_arm_handle_step_debug(vcpu, run))
- handled = 0;
-
return handled;
}
@@ -269,12 +262,7 @@ int handle_exit(struct kvm_vcpu *vcpu, struct kvm_run *run,
case ARM_EXCEPTION_IRQ:
return 1;
case ARM_EXCEPTION_EL1_SERROR:
- /* We may still need to return for single-step */
- if (!(*vcpu_cpsr(vcpu) & DBG_SPSR_SS)
- && kvm_arm_handle_step_debug(vcpu, run))
- return 0;
- else
- return 1;
+ return 1;
case ARM_EXCEPTION_TRAP:
return handle_trap_exceptions(vcpu, run);
case ARM_EXCEPTION_HYP_GONE:
diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c
index 7cc175c88a37..4282f05771c1 100644
--- a/arch/arm64/kvm/hyp/switch.c
+++ b/arch/arm64/kvm/hyp/switch.c
@@ -305,33 +305,6 @@ static bool __hyp_text __populate_fault_info(struct kvm_vcpu *vcpu)
return true;
}
-/* Skip an instruction which has been emulated. Returns true if
- * execution can continue or false if we need to exit hyp mode because
- * single-step was in effect.
- */
-static bool __hyp_text __skip_instr(struct kvm_vcpu *vcpu)
-{
- *vcpu_pc(vcpu) = read_sysreg_el2(elr);
-
- if (vcpu_mode_is_32bit(vcpu)) {
- vcpu->arch.ctxt.gp_regs.regs.pstate = read_sysreg_el2(spsr);
- kvm_skip_instr32(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
- write_sysreg_el2(vcpu->arch.ctxt.gp_regs.regs.pstate, spsr);
- } else {
- *vcpu_pc(vcpu) += 4;
- }
-
- write_sysreg_el2(*vcpu_pc(vcpu), elr);
-
- if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP) {
- vcpu->arch.fault.esr_el2 =
- (ESR_ELx_EC_SOFTSTP_LOW << ESR_ELx_EC_SHIFT) | 0x22;
- return false;
- } else {
- return true;
- }
-}
-
static bool __hyp_text __hyp_switch_fpsimd(struct kvm_vcpu *vcpu)
{
struct user_fpsimd_state *host_fpsimd = vcpu->arch.host_fpsimd_state;
@@ -420,20 +393,12 @@ static bool __hyp_text fixup_guest_exit(struct kvm_vcpu *vcpu, u64 *exit_code)
if (valid) {
int ret = __vgic_v2_perform_cpuif_access(vcpu);
- if (ret == 1 && __skip_instr(vcpu))
+ if (ret == 1)
return true;
- if (ret == -1) {
- /* Promote an illegal access to an
- * SError. If we would be returning
- * due to single-step clear the SS
- * bit so handle_exit knows what to
- * do after dealing with the error.
- */
- if (!__skip_instr(vcpu))
- *vcpu_cpsr(vcpu) &= ~DBG_SPSR_SS;
+ /* Promote an illegal access to an SError.*/
+ if (ret == -1)
*exit_code = ARM_EXCEPTION_EL1_SERROR;
- }
goto exit;
}
@@ -444,7 +409,7 @@ static bool __hyp_text fixup_guest_exit(struct kvm_vcpu *vcpu, u64 *exit_code)
kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_CP15_32)) {
int ret = __vgic_v3_perform_cpuif_access(vcpu);
- if (ret == 1 && __skip_instr(vcpu))
+ if (ret == 1)
return true;
}
diff --git a/arch/arm64/kvm/hyp/vgic-v2-cpuif-proxy.c b/arch/arm64/kvm/hyp/vgic-v2-cpuif-proxy.c
index 215c7c0eb3b0..9cbdd034a563 100644
--- a/arch/arm64/kvm/hyp/vgic-v2-cpuif-proxy.c
+++ b/arch/arm64/kvm/hyp/vgic-v2-cpuif-proxy.c
@@ -41,7 +41,7 @@ static bool __hyp_text __is_be(struct kvm_vcpu *vcpu)
* Returns:
* 1: GICV access successfully performed
* 0: Not a GICV access
- * -1: Illegal GICV access
+ * -1: Illegal GICV access successfully performed
*/
int __hyp_text __vgic_v2_perform_cpuif_access(struct kvm_vcpu *vcpu)
{
@@ -61,12 +61,16 @@ int __hyp_text __vgic_v2_perform_cpuif_access(struct kvm_vcpu *vcpu)
return 0;
/* Reject anything but a 32bit access */
- if (kvm_vcpu_dabt_get_as(vcpu) != sizeof(u32))
+ if (kvm_vcpu_dabt_get_as(vcpu) != sizeof(u32)) {
+ __kvm_skip_instr(vcpu);
return -1;
+ }
/* Not aligned? Don't bother */
- if (fault_ipa & 3)
+ if (fault_ipa & 3) {
+ __kvm_skip_instr(vcpu);
return -1;
+ }
rd = kvm_vcpu_dabt_get_rd(vcpu);
addr = hyp_symbol_addr(kvm_vgic_global_state)->vcpu_hyp_va;
@@ -88,5 +92,7 @@ int __hyp_text __vgic_v2_perform_cpuif_access(struct kvm_vcpu *vcpu)
vcpu_set_reg(vcpu, rd, data);
}
+ __kvm_skip_instr(vcpu);
+
return 1;
}
diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c
index 23774970c9df..4adcee5fc126 100644
--- a/virt/kvm/arm/arm.c
+++ b/virt/kvm/arm/arm.c
@@ -674,8 +674,6 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
ret = kvm_handle_mmio_return(vcpu, vcpu->run);
if (ret)
return ret;
- if (kvm_arm_handle_step_debug(vcpu, vcpu->run))
- return 0;
}
if (run->immediate_exit)
diff --git a/virt/kvm/arm/hyp/vgic-v3-sr.c b/virt/kvm/arm/hyp/vgic-v3-sr.c
index 616e5a433ab0..9652c453480f 100644
--- a/virt/kvm/arm/hyp/vgic-v3-sr.c
+++ b/virt/kvm/arm/hyp/vgic-v3-sr.c
@@ -1012,8 +1012,10 @@ int __hyp_text __vgic_v3_perform_cpuif_access(struct kvm_vcpu *vcpu)
esr = kvm_vcpu_get_hsr(vcpu);
if (vcpu_mode_is_32bit(vcpu)) {
- if (!kvm_condition_valid(vcpu))
+ if (!kvm_condition_valid(vcpu)) {
+ __kvm_skip_instr(vcpu);
return 1;
+ }
sysreg = esr_cp15_to_sysreg(esr);
} else {
@@ -1123,6 +1125,8 @@ int __hyp_text __vgic_v3_perform_cpuif_access(struct kvm_vcpu *vcpu)
rt = kvm_vcpu_sys_get_rt(vcpu);
fn(vcpu, vmcr, rt);
+ __kvm_skip_instr(vcpu);
+
return 1;
}
--
2.19.2
_______________________________________________
kvmarm mailing list
kvmarm@lists.cs.columbia.edu
https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
WARNING: multiple messages have this Message-ID (diff)
From: Marc Zyngier <marc.zyngier@arm.com>
To: "Paolo Bonzini" <pbonzini@redhat.com>,
"Radim Krčmář" <rkrcmar@redhat.com>
Cc: "Mark Rutland" <mark.rutland@arm.com>,
"Punit Agrawal" <punit.agrawal@arm.com>,
kvm@vger.kernel.org, "Julien Thierry" <julien.thierry@arm.com>,
"Gustavo A . R . Silva" <gustavo@embeddedor.com>,
"Will Deacon" <will.deacon@arm.com>,
"Christoffer Dall" <christoffer.dall@arm.com>,
linux-arm-kernel@lists.infradead.org, punitagrawal@gmail.com,
"Alex Bennée" <alex.bennee@linaro.org>,
kvmarm@lists.cs.columbia.edu,
"Suzuki Poulose" <suzuki.poulose@arm.com>,
"Lukas Braun" <koomi@moshbit.net>
Subject: [PATCH 02/28] arm64: KVM: Consistently advance singlestep when emulating instructions
Date: Wed, 19 Dec 2018 18:03:23 +0000 [thread overview]
Message-ID: <20181219180349.242681-3-marc.zyngier@arm.com> (raw)
In-Reply-To: <20181219180349.242681-1-marc.zyngier@arm.com>
From: Mark Rutland <mark.rutland@arm.com>
When we emulate a guest instruction, we don't advance the hardware
singlestep state machine, and thus the guest will receive a software
step exception after a next instruction which is not emulated by the
host.
We bodge around this in an ad-hoc fashion. Sometimes we explicitly check
whether userspace requested a single step, and fake a debug exception
from within the kernel. Other times, we advance the HW singlestep state
rely on the HW to generate the exception for us. Thus, the observed step
behaviour differs for host and guest.
Let's make this simpler and consistent by always advancing the HW
singlestep state machine when we skip an instruction. Thus we can rely
on the hardware to generate the singlestep exception for us, and never
need to explicitly check for an active-pending step, nor do we need to
fake a debug exception from the guest.
Cc: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
arch/arm/include/asm/kvm_host.h | 5 ---
arch/arm64/include/asm/kvm_emulate.h | 35 ++++++++++++++-----
arch/arm64/include/asm/kvm_host.h | 1 -
arch/arm64/kvm/debug.c | 21 ------------
arch/arm64/kvm/handle_exit.c | 14 +-------
arch/arm64/kvm/hyp/switch.c | 43 +++---------------------
arch/arm64/kvm/hyp/vgic-v2-cpuif-proxy.c | 12 +++++--
virt/kvm/arm/arm.c | 2 --
virt/kvm/arm/hyp/vgic-v3-sr.c | 6 +++-
9 files changed, 46 insertions(+), 93 deletions(-)
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
index 5ca5d9af0c26..c5634c6ffcea 100644
--- a/arch/arm/include/asm/kvm_host.h
+++ b/arch/arm/include/asm/kvm_host.h
@@ -296,11 +296,6 @@ static inline void kvm_arm_init_debug(void) {}
static inline void kvm_arm_setup_debug(struct kvm_vcpu *vcpu) {}
static inline void kvm_arm_clear_debug(struct kvm_vcpu *vcpu) {}
static inline void kvm_arm_reset_debug_ptr(struct kvm_vcpu *vcpu) {}
-static inline bool kvm_arm_handle_step_debug(struct kvm_vcpu *vcpu,
- struct kvm_run *run)
-{
- return false;
-}
int kvm_arm_vcpu_arch_set_attr(struct kvm_vcpu *vcpu,
struct kvm_device_attr *attr);
diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h
index 21247870def7..506386a3edde 100644
--- a/arch/arm64/include/asm/kvm_emulate.h
+++ b/arch/arm64/include/asm/kvm_emulate.h
@@ -24,6 +24,7 @@
#include <linux/kvm_host.h>
+#include <asm/debug-monitors.h>
#include <asm/esr.h>
#include <asm/kvm_arm.h>
#include <asm/kvm_hyp.h>
@@ -147,14 +148,6 @@ static inline bool kvm_condition_valid(const struct kvm_vcpu *vcpu)
return true;
}
-static inline void kvm_skip_instr(struct kvm_vcpu *vcpu, bool is_wide_instr)
-{
- if (vcpu_mode_is_32bit(vcpu))
- kvm_skip_instr32(vcpu, is_wide_instr);
- else
- *vcpu_pc(vcpu) += 4;
-}
-
static inline void vcpu_set_thumb(struct kvm_vcpu *vcpu)
{
*vcpu_cpsr(vcpu) |= PSR_AA32_T_BIT;
@@ -424,4 +417,30 @@ static inline unsigned long vcpu_data_host_to_guest(struct kvm_vcpu *vcpu,
return data; /* Leave LE untouched */
}
+static inline void kvm_skip_instr(struct kvm_vcpu *vcpu, bool is_wide_instr)
+{
+ if (vcpu_mode_is_32bit(vcpu))
+ kvm_skip_instr32(vcpu, is_wide_instr);
+ else
+ *vcpu_pc(vcpu) += 4;
+
+ /* advance the singlestep state machine */
+ *vcpu_cpsr(vcpu) &= ~DBG_SPSR_SS;
+}
+
+/*
+ * Skip an instruction which has been emulated at hyp while most guest sysregs
+ * are live.
+ */
+static inline void __hyp_text __kvm_skip_instr(struct kvm_vcpu *vcpu)
+{
+ *vcpu_pc(vcpu) = read_sysreg_el2(elr);
+ vcpu->arch.ctxt.gp_regs.regs.pstate = read_sysreg_el2(spsr);
+
+ kvm_skip_instr(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
+
+ write_sysreg_el2(vcpu->arch.ctxt.gp_regs.regs.pstate, spsr);
+ write_sysreg_el2(*vcpu_pc(vcpu), elr);
+}
+
#endif /* __ARM64_KVM_EMULATE_H__ */
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 52fbc823ff8c..7a5035f9c5c3 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -445,7 +445,6 @@ void kvm_arm_init_debug(void);
void kvm_arm_setup_debug(struct kvm_vcpu *vcpu);
void kvm_arm_clear_debug(struct kvm_vcpu *vcpu);
void kvm_arm_reset_debug_ptr(struct kvm_vcpu *vcpu);
-bool kvm_arm_handle_step_debug(struct kvm_vcpu *vcpu, struct kvm_run *run);
int kvm_arm_vcpu_arch_set_attr(struct kvm_vcpu *vcpu,
struct kvm_device_attr *attr);
int kvm_arm_vcpu_arch_get_attr(struct kvm_vcpu *vcpu,
diff --git a/arch/arm64/kvm/debug.c b/arch/arm64/kvm/debug.c
index 00d422336a45..f39801e4136c 100644
--- a/arch/arm64/kvm/debug.c
+++ b/arch/arm64/kvm/debug.c
@@ -236,24 +236,3 @@ void kvm_arm_clear_debug(struct kvm_vcpu *vcpu)
}
}
}
-
-
-/*
- * After successfully emulating an instruction, we might want to
- * return to user space with a KVM_EXIT_DEBUG. We can only do this
- * once the emulation is complete, though, so for userspace emulations
- * we have to wait until we have re-entered KVM before calling this
- * helper.
- *
- * Return true (and set exit_reason) to return to userspace or false
- * if no further action is required.
- */
-bool kvm_arm_handle_step_debug(struct kvm_vcpu *vcpu, struct kvm_run *run)
-{
- if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP) {
- run->exit_reason = KVM_EXIT_DEBUG;
- run->debug.arch.hsr = ESR_ELx_EC_SOFTSTP_LOW << ESR_ELx_EC_SHIFT;
- return true;
- }
- return false;
-}
diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c
index 35a81bebd02b..b0643f9c4873 100644
--- a/arch/arm64/kvm/handle_exit.c
+++ b/arch/arm64/kvm/handle_exit.c
@@ -229,13 +229,6 @@ static int handle_trap_exceptions(struct kvm_vcpu *vcpu, struct kvm_run *run)
handled = exit_handler(vcpu, run);
}
- /*
- * kvm_arm_handle_step_debug() sets the exit_reason on the kvm_run
- * structure if we need to return to userspace.
- */
- if (handled > 0 && kvm_arm_handle_step_debug(vcpu, run))
- handled = 0;
-
return handled;
}
@@ -269,12 +262,7 @@ int handle_exit(struct kvm_vcpu *vcpu, struct kvm_run *run,
case ARM_EXCEPTION_IRQ:
return 1;
case ARM_EXCEPTION_EL1_SERROR:
- /* We may still need to return for single-step */
- if (!(*vcpu_cpsr(vcpu) & DBG_SPSR_SS)
- && kvm_arm_handle_step_debug(vcpu, run))
- return 0;
- else
- return 1;
+ return 1;
case ARM_EXCEPTION_TRAP:
return handle_trap_exceptions(vcpu, run);
case ARM_EXCEPTION_HYP_GONE:
diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c
index 7cc175c88a37..4282f05771c1 100644
--- a/arch/arm64/kvm/hyp/switch.c
+++ b/arch/arm64/kvm/hyp/switch.c
@@ -305,33 +305,6 @@ static bool __hyp_text __populate_fault_info(struct kvm_vcpu *vcpu)
return true;
}
-/* Skip an instruction which has been emulated. Returns true if
- * execution can continue or false if we need to exit hyp mode because
- * single-step was in effect.
- */
-static bool __hyp_text __skip_instr(struct kvm_vcpu *vcpu)
-{
- *vcpu_pc(vcpu) = read_sysreg_el2(elr);
-
- if (vcpu_mode_is_32bit(vcpu)) {
- vcpu->arch.ctxt.gp_regs.regs.pstate = read_sysreg_el2(spsr);
- kvm_skip_instr32(vcpu, kvm_vcpu_trap_il_is32bit(vcpu));
- write_sysreg_el2(vcpu->arch.ctxt.gp_regs.regs.pstate, spsr);
- } else {
- *vcpu_pc(vcpu) += 4;
- }
-
- write_sysreg_el2(*vcpu_pc(vcpu), elr);
-
- if (vcpu->guest_debug & KVM_GUESTDBG_SINGLESTEP) {
- vcpu->arch.fault.esr_el2 =
- (ESR_ELx_EC_SOFTSTP_LOW << ESR_ELx_EC_SHIFT) | 0x22;
- return false;
- } else {
- return true;
- }
-}
-
static bool __hyp_text __hyp_switch_fpsimd(struct kvm_vcpu *vcpu)
{
struct user_fpsimd_state *host_fpsimd = vcpu->arch.host_fpsimd_state;
@@ -420,20 +393,12 @@ static bool __hyp_text fixup_guest_exit(struct kvm_vcpu *vcpu, u64 *exit_code)
if (valid) {
int ret = __vgic_v2_perform_cpuif_access(vcpu);
- if (ret == 1 && __skip_instr(vcpu))
+ if (ret == 1)
return true;
- if (ret == -1) {
- /* Promote an illegal access to an
- * SError. If we would be returning
- * due to single-step clear the SS
- * bit so handle_exit knows what to
- * do after dealing with the error.
- */
- if (!__skip_instr(vcpu))
- *vcpu_cpsr(vcpu) &= ~DBG_SPSR_SS;
+ /* Promote an illegal access to an SError.*/
+ if (ret == -1)
*exit_code = ARM_EXCEPTION_EL1_SERROR;
- }
goto exit;
}
@@ -444,7 +409,7 @@ static bool __hyp_text fixup_guest_exit(struct kvm_vcpu *vcpu, u64 *exit_code)
kvm_vcpu_trap_get_class(vcpu) == ESR_ELx_EC_CP15_32)) {
int ret = __vgic_v3_perform_cpuif_access(vcpu);
- if (ret == 1 && __skip_instr(vcpu))
+ if (ret == 1)
return true;
}
diff --git a/arch/arm64/kvm/hyp/vgic-v2-cpuif-proxy.c b/arch/arm64/kvm/hyp/vgic-v2-cpuif-proxy.c
index 215c7c0eb3b0..9cbdd034a563 100644
--- a/arch/arm64/kvm/hyp/vgic-v2-cpuif-proxy.c
+++ b/arch/arm64/kvm/hyp/vgic-v2-cpuif-proxy.c
@@ -41,7 +41,7 @@ static bool __hyp_text __is_be(struct kvm_vcpu *vcpu)
* Returns:
* 1: GICV access successfully performed
* 0: Not a GICV access
- * -1: Illegal GICV access
+ * -1: Illegal GICV access successfully performed
*/
int __hyp_text __vgic_v2_perform_cpuif_access(struct kvm_vcpu *vcpu)
{
@@ -61,12 +61,16 @@ int __hyp_text __vgic_v2_perform_cpuif_access(struct kvm_vcpu *vcpu)
return 0;
/* Reject anything but a 32bit access */
- if (kvm_vcpu_dabt_get_as(vcpu) != sizeof(u32))
+ if (kvm_vcpu_dabt_get_as(vcpu) != sizeof(u32)) {
+ __kvm_skip_instr(vcpu);
return -1;
+ }
/* Not aligned? Don't bother */
- if (fault_ipa & 3)
+ if (fault_ipa & 3) {
+ __kvm_skip_instr(vcpu);
return -1;
+ }
rd = kvm_vcpu_dabt_get_rd(vcpu);
addr = hyp_symbol_addr(kvm_vgic_global_state)->vcpu_hyp_va;
@@ -88,5 +92,7 @@ int __hyp_text __vgic_v2_perform_cpuif_access(struct kvm_vcpu *vcpu)
vcpu_set_reg(vcpu, rd, data);
}
+ __kvm_skip_instr(vcpu);
+
return 1;
}
diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c
index 23774970c9df..4adcee5fc126 100644
--- a/virt/kvm/arm/arm.c
+++ b/virt/kvm/arm/arm.c
@@ -674,8 +674,6 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
ret = kvm_handle_mmio_return(vcpu, vcpu->run);
if (ret)
return ret;
- if (kvm_arm_handle_step_debug(vcpu, vcpu->run))
- return 0;
}
if (run->immediate_exit)
diff --git a/virt/kvm/arm/hyp/vgic-v3-sr.c b/virt/kvm/arm/hyp/vgic-v3-sr.c
index 616e5a433ab0..9652c453480f 100644
--- a/virt/kvm/arm/hyp/vgic-v3-sr.c
+++ b/virt/kvm/arm/hyp/vgic-v3-sr.c
@@ -1012,8 +1012,10 @@ int __hyp_text __vgic_v3_perform_cpuif_access(struct kvm_vcpu *vcpu)
esr = kvm_vcpu_get_hsr(vcpu);
if (vcpu_mode_is_32bit(vcpu)) {
- if (!kvm_condition_valid(vcpu))
+ if (!kvm_condition_valid(vcpu)) {
+ __kvm_skip_instr(vcpu);
return 1;
+ }
sysreg = esr_cp15_to_sysreg(esr);
} else {
@@ -1123,6 +1125,8 @@ int __hyp_text __vgic_v3_perform_cpuif_access(struct kvm_vcpu *vcpu)
rt = kvm_vcpu_sys_get_rt(vcpu);
fn(vcpu, vmcr, rt);
+ __kvm_skip_instr(vcpu);
+
return 1;
}
--
2.19.2
_______________________________________________
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next prev parent reply other threads:[~2018-12-19 18:03 UTC|newest]
Thread overview: 60+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-12-19 18:03 [GIT PULL] KVM/arm updates for 4.21 Marc Zyngier
2018-12-19 18:03 ` Marc Zyngier
2018-12-19 18:03 ` [PATCH 01/28] arm64: KVM: Skip MMIO insn after emulation Marc Zyngier
2018-12-19 18:03 ` Marc Zyngier
2018-12-19 18:03 ` Marc Zyngier [this message]
2018-12-19 18:03 ` [PATCH 02/28] arm64: KVM: Consistently advance singlestep when emulating instructions Marc Zyngier
2018-12-19 18:03 ` [PATCH 03/28] KVM: arm/arm64: Fix VMID alloc race by reverting to lock-less Marc Zyngier
2018-12-19 18:03 ` Marc Zyngier
2018-12-19 18:03 ` [PATCH 04/28] KVM: arm/arm64: Log PSTATE for unhandled sysregs Marc Zyngier
2018-12-19 18:03 ` Marc Zyngier
2018-12-19 18:03 ` [PATCH 05/28] KVM: arm/arm64: vgic-v2: Set active_source to 0 when restoring state Marc Zyngier
2018-12-19 18:03 ` Marc Zyngier
2018-12-19 18:03 ` [PATCH 06/28] KVM: arm/arm64: Share common code in user_mem_abort() Marc Zyngier
2018-12-19 18:03 ` Marc Zyngier
2018-12-19 18:03 ` [PATCH 07/28] KVM: arm/arm64: Re-factor setting the Stage 2 entry to exec on fault Marc Zyngier
2018-12-19 18:03 ` Marc Zyngier
2018-12-19 18:03 ` [PATCH 08/28] KVM: arm/arm64: Introduce helpers to manipulate page table entries Marc Zyngier
2018-12-19 18:03 ` Marc Zyngier
2018-12-19 18:03 ` [PATCH 09/28] KVM: arm64: Support dirty page tracking for PUD hugepages Marc Zyngier
2018-12-19 18:03 ` Marc Zyngier
2018-12-19 18:03 ` [PATCH 10/28] KVM: arm64: Support PUD hugepage in stage2_is_exec() Marc Zyngier
2018-12-19 18:03 ` Marc Zyngier
2018-12-19 18:03 ` [PATCH 11/28] KVM: arm64: Support handling access faults for PUD hugepages Marc Zyngier
2018-12-19 18:03 ` Marc Zyngier
2018-12-19 18:03 ` [PATCH 12/28] KVM: arm64: Update age handlers to support " Marc Zyngier
2018-12-19 18:03 ` Marc Zyngier
2018-12-19 18:03 ` [PATCH 13/28] KVM: arm64: Add support for creating PUD hugepages at stage 2 Marc Zyngier
2018-12-19 18:03 ` Marc Zyngier
2018-12-19 18:03 ` [PATCH 14/28] KVM: arm/arm64: vgic: Do not cond_resched_lock() with IRQs disabled Marc Zyngier
2018-12-19 18:03 ` Marc Zyngier
2018-12-19 18:03 ` [PATCH 15/28] KVM: arm64: Clarify explanation of STAGE2_PGTABLE_LEVELS Marc Zyngier
2018-12-19 18:03 ` Marc Zyngier
2018-12-19 18:03 ` [PATCH 16/28] KVM: arm/arm64: vgic: Cap SPIs to the VM-defined maximum Marc Zyngier
2018-12-19 18:03 ` Marc Zyngier
2018-12-19 18:03 ` [PATCH 17/28] KVM: arm/arm64: vgic: Fix off-by-one bug in vgic_get_irq() Marc Zyngier
2018-12-19 18:03 ` Marc Zyngier
2018-12-19 18:03 ` [PATCH 18/28] KVM: arm/arm64: vgic: Consider priority and active state for pending irq Marc Zyngier
2018-12-19 18:03 ` Marc Zyngier
2018-12-19 18:03 ` [PATCH 19/28] KVM: arm/arm64: Fixup the kvm_exit tracepoint Marc Zyngier
2018-12-19 18:03 ` Marc Zyngier
2018-12-19 18:03 ` [PATCH 20/28] KVM: arm/arm64: Remove arch timer workqueue Marc Zyngier
2018-12-19 18:03 ` Marc Zyngier
2018-12-19 18:03 ` [PATCH 21/28] KVM: arm/arm64: arch_timer: Simplify kvm_timer_vcpu_terminate Marc Zyngier
2018-12-19 18:03 ` Marc Zyngier
2018-12-19 18:03 ` [PATCH 22/28] KVM: arm64: Make vcpu const in vcpu_read_sys_reg Marc Zyngier
2018-12-19 18:03 ` Marc Zyngier
2018-12-19 18:03 ` [PATCH 23/28] arm64: KVM: Add trapped system register access tracepoint Marc Zyngier
2018-12-19 18:03 ` Marc Zyngier
2018-12-19 18:03 ` [PATCH 24/28] arm/arm64: KVM: vgic: Force VM halt when changing the active state of GICv3 PPIs/SGIs Marc Zyngier
2018-12-19 18:03 ` Marc Zyngier
2018-12-19 18:03 ` [PATCH 25/28] KVM: arm/arm64: Fix unintended stage 2 PMD mappings Marc Zyngier
2018-12-19 18:03 ` Marc Zyngier
2018-12-19 18:03 ` [PATCH 26/28] arm64: KVM: Avoid setting the upper 32 bits of VTCR_EL2 to 1 Marc Zyngier
2018-12-19 18:03 ` Marc Zyngier
2018-12-19 18:03 ` [PATCH 27/28] arm/arm64: KVM: Add ARM_EXCEPTION_IS_TRAP macro Marc Zyngier
2018-12-19 18:03 ` Marc Zyngier
2018-12-19 18:03 ` [PATCH 28/28] arm: KVM: Add S2_PMD_{MASK,SIZE} constants Marc Zyngier
2018-12-19 18:03 ` Marc Zyngier
2018-12-19 19:34 ` [GIT PULL] KVM/arm updates for 4.21 Paolo Bonzini
2018-12-19 19:34 ` Paolo Bonzini
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