According to section "VMRUN and TF/RF Bits in EFLAGS" in AMD APM vol 2,
"From the host point of view, VMRUN acts like a single instruction,
even though an arbitrary number of guest instructions may execute
before a #VMEXIT effectively completes the VMRUN. As a single
host instruction, VMRUN interacts with EFLAGS.TF like ordinary
instructions. EFLAGS.TF causes a #DB trap after the VMRUN completes
on the host side (i.e., after the #VMEXIT from the guest)."
Patch# 1 replaces a hard-coded value with a #define.
Patch# 2 modifies the assembly in svm_vmrun() so that a Single-Step breakpoint
can placed right before the VMRUN instruction. It also adds helper functions
for setting/un-setting that breakpoint.
Patch# 3 adds a test for the RFLAGS.TF on VMRUN.
[PATCH 1/3] KVM: SVM: Replace hard-coded value with #define
[PATCH 2/3] nVMX: Add helper functions to set/unset host RFLAGS.TF on
[PATCH 3/3] nSVM: Test effect of host RFLAGS.TF on VMRUN
arch/x86/kvm/svm/svm.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
Krish Sadhukhan (1):
KVM: SVM: Replace hard-coded value with #define
x86/svm.c | 24 +++++++++++++--
x86/svm.h | 3 ++
x86/svm_tests.c | 94 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
3 files changed, 118 insertions(+), 3 deletions(-)
Krish Sadhukhan (2):
nVMX: Add helper functions to set/unset host RFLAGS.TF on the VMRUN instruction
nSVM: Test effect of host RFLAGS.TF on VMRUN
