On Wed, Sep 10, 2025, Hou Wenlong wrote:
Similar to the global disable test case in x86's debug_regs test, use 'KVM_FEP' to trigger instruction emulation in order to verify the guest debug DR7.GD checking during instruction emulation.
Signed-off-by: Hou Wenlong houwenlong.hwl@antgroup.com
tools/testing/selftests/kvm/x86/debug_regs.c | 25 +++++++++++++++++++- 1 file changed, 24 insertions(+), 1 deletion(-)
diff --git a/tools/testing/selftests/kvm/x86/debug_regs.c b/tools/testing/selftests/kvm/x86/debug_regs.c index 2d814c1d1dc4..ba80b77c2869 100644 --- a/tools/testing/selftests/kvm/x86/debug_regs.c +++ b/tools/testing/selftests/kvm/x86/debug_regs.c @@ -19,6 +19,7 @@ uint32_t guest_value; extern unsigned char sw_bp, hw_bp, write_data, ss_start, bd_start; +extern unsigned char fep_bd_start; static void guest_code(void) { @@ -64,6 +65,12 @@ static void guest_code(void) /* DR6.BD test */ asm volatile("bd_start: mov %%dr0, %%rax" : : : "rax");
- if (is_forced_emulation_enabled) {
/* DR6.BD test for emulation */
Put the comment above the if-statement, that way there's no need for curly braces. Or just drop it entirely; unless the comments more verbose, I don't think it adds much value.
asm volatile(KVM_FEP "fep_bd_start: mov %%dr0, %%rax" : : : "rax");- }
- GUEST_DONE();
} @@ -185,7 +192,7 @@ int main(void) target_dr6); }
- /* Finally test global disable */
- /* test global disable */ memset(&debug, 0, sizeof(debug)); debug.control = KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_USE_HW_BP; debug.arch.debugreg[7] = 0x400 | DR7_GD;
@@ -202,6 +209,22 @@ int main(void) run->debug.arch.pc, target_rip, run->debug.arch.dr6, target_dr6);
- /* test global disable in emulation */
- if (is_forced_emulation_enabled) {
/* Skip the 3-bytes "mov dr0" */vcpu_skip_insn(vcpu, 3);vcpu_run(vcpu);TEST_ASSERT(run->exit_reason == KVM_EXIT_DEBUG &&run->debug.arch.exception == DB_VECTOR &&run->debug.arch.pc == CAST_TO_RIP(fep_bd_start) &&run->debug.arch.dr6 == target_dr6,"DR7.GD: exit %d exception %d rip 0x%llx ""(should be 0x%llx) dr6 0x%llx (should be 0x%llx)",run->exit_reason, run->debug.arch.exception,run->debug.arch.pc, target_rip, run->debug.arch.dr6,target_dr6);- }
- /* Disable all debug controls, run to the end */ memset(&debug, 0, sizeof(debug)); vcpu_guest_debug_set(vcpu, &debug);
-- 2.31.1