lkml.org 
[lkml]   [2017]   [Nov]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v1 1/2] kvm: arm64: handle single-step during SError exceptions
Date
When an SError arrives during single-step it may be delivered before
the step completes. In that case the DBG_SPSR_SS bit will have flipped
as the instruction executed. After handling the abort in handle_exit()
we test to see if the bit is clear and we were single-stepping before
deciding if we need to exit to user space.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
---
arch/arm64/kvm/handle_exit.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/kvm/handle_exit.c b/arch/arm64/kvm/handle_exit.c
index 3e645ec9e751..3ba8c4a3bcff 100644
--- a/arch/arm64/kvm/handle_exit.c
+++ b/arch/arm64/kvm/handle_exit.c
@@ -28,6 +28,7 @@
#include <asm/kvm_emulate.h>
#include <asm/kvm_mmu.h>
#include <asm/kvm_psci.h>
+#include <asm/debug-monitors.h>

#define CREATE_TRACE_POINTS
#include "trace.h"
@@ -250,7 +251,12 @@ int handle_exit(struct kvm_vcpu *vcpu, struct kvm_run *run,
return 1;
case ARM_EXCEPTION_EL1_SERROR:
kvm_inject_vabt(vcpu);
- return 1;
+ /* 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;
case ARM_EXCEPTION_TRAP:
return handle_trap_exceptions(vcpu, run);
case ARM_EXCEPTION_HYP_GONE:
--
2.15.0
\
 
 \ /
  Last update: 2017-11-23 13:12    [W:0.046 / U:1.736 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site