On 6/4/24 02:18, Paolo Bonzini wrote:
If the required DR7 (either from the VMCB or from the host save
area) disables a breakpoint that was enabled prior to vmentry
or vmexit, it is left enabled and will trigger EXCP_DEBUG.
This causes a spurious #DB on the next crossing of the breakpoint.
To disable it, vmentry/vmexit must use cpu_x86_update_dr7
to load DR7.
Because cpu_x86_update_dr7 takes a 32-bit argument, check
reserved bits prior to calling cpu_x86_update_dr7, and do the
same for DR6 as well for consistency.
This scenario is tested by the "host_rflags" test in kvm-unit-tests.
Signed-off-by: Paolo Bonzini<pbonz...@redhat.com>
---
target/i386/tcg/sysemu/svm_helper.c | 25 +++++++++++++++----------
1 file changed, 15 insertions(+), 10 deletions(-)
Reviewed-by: Richard Henderson <richard.hender...@linaro.org>
r~
