Test the undocumented ICEBP (aka INT1 or INT01) opcode, and test that
dr6.BS is not modified by neither watchpoints nor breakpoints.
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
---
x86/debug.c | 51 ++++++++++++++++++++++++++++++++++++++++++++-------
1 file changed, 44 insertions(+), 7 deletions(-)
diff --git a/x86/debug.c b/x86/debug.c
index 34e56fb..d04de23 100644
--- a/x86/debug.c
+++ b/x86/debug.c
@@ -34,6 +34,11 @@ static void set_dr1(void *value)
asm volatile("mov %0,%%dr1" : : "r" (value));
}
+static void set_dr6(unsigned long value)
+{
+ asm volatile("mov %0,%%dr6" : : "r" (value));
+}
+
static void set_dr7(unsigned long value)
{
asm volatile("mov %0,%%dr7" : : "r" (value));
@@ -70,15 +75,26 @@ sw_bp:
asm volatile("int3");
report("#BP", bp_addr[0] == (unsigned long)&&sw_bp + 1);
- set_dr0(&&hw_bp);
+ n = 0;
+ set_dr0(&&hw_bp1);
set_dr7(0x00000402);
-hw_bp:
+hw_bp1:
asm volatile("nop");
- report("hw breakpoint",
+ report("hw breakpoint (test that dr6.BS is not set)",
n == 1 &&
- bp_addr[0] == ((unsigned long)&&hw_bp) && dr6[0] == 0xffff0ff1);
+ bp_addr[0] == ((unsigned long)&&hw_bp1) && dr6[0] == 0xffff0ff1);
n = 0;
+ set_dr0(&&hw_bp2);
+ set_dr6(0x00004002);
+hw_bp2:
+ asm volatile("nop");
+ report("hw breakpoint (test that dr6.BS is not cleared)",
+ n == 1 &&
+ bp_addr[0] == ((unsigned long)&&hw_bp2) && dr6[0] == 0xffff4ff1);
+
+ n = 0;
+ set_dr6(0);
asm volatile(
"pushf\n\t"
"pop %%rax\n\t"
@@ -104,10 +120,31 @@ hw_bp:
"mov $42,%%rax\n\t"
"mov %%rax,%0\n\t"
: "=m" (value) : : "rax");
-hw_wp:
- report("hw watchpoint",
+hw_wp1:
+ report("hw watchpoint (test that dr6.BS is not cleared)",
n == 1 &&
- bp_addr[0] == ((unsigned long)&&hw_wp) && dr6[0] == 0xffff4ff2);
+ bp_addr[0] == ((unsigned long)&&hw_wp1) && dr6[0] == 0xffff4ff2);
+
+ n = 0;
+ set_dr6(0);
+
+ asm volatile(
+ "mov $42,%%rax\n\t"
+ "mov %%rax,%0\n\t"
+ : "=m" (value) : : "rax");
+hw_wp2:
+ report("hw watchpoint (test that dr6.BS is not set)",
+ n == 1 &&
+ bp_addr[0] == ((unsigned long)&&hw_wp2) && dr6[0] == 0xffff0ff2);
+
+ n = 0;
+ set_dr6(0);
+sw_icebp:
+ asm volatile(".byte 0xf1");
+ report("icebp",
+ n == 1 &&
+ bp_addr[0] == (unsigned long)&&sw_icebp + 1 &&
+ dr6[0] == 0xffff0ff0);
return report_summary();
}
--
1.8.3.1
--
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