From: Jan Kiszka <jan.kiszka@xxxxxxxxxxx>
This adds a basic test for INT3/#BP, hardware breakpoints, hardware
watchpoints and single-stepping.
Signed-off-by: Jan Kiszka <jan.kiszka@xxxxxxxxxxx>
---
config-x86-common.mak | 2 +
config-x86_64.mak | 2 +-
lib/x86/desc.h | 2 +
x86/debug.c | 113 ++++++++++++++++++++++++++++++++++++++++++++++++++
x86/unittests.cfg | 3 ++
5 files changed, 121 insertions(+), 1 deletion(-)
create mode 100644 x86/debug.c
diff --git a/config-x86-common.mak b/config-x86-common.mak
index 32da7fb..aa5a439 100644
--- a/config-x86-common.mak
+++ b/config-x86-common.mak
@@ -103,6 +103,8 @@ $(TEST_DIR)/pcid.elf: $(cstart.o) $(TEST_DIR)/pcid.o
$(TEST_DIR)/vmx.elf: $(cstart.o) $(TEST_DIR)/vmx.o $(TEST_DIR)/vmx_tests.o
+$(TEST_DIR)/debug.elf: $(cstart.o) $(TEST_DIR)/debug.o
+
arch_clean:
$(RM) $(TEST_DIR)/*.o $(TEST_DIR)/*.flat $(TEST_DIR)/*.elf \
$(TEST_DIR)/.*.d $(TEST_DIR)/lib/.*.d $(TEST_DIR)/lib/*.o
diff --git a/config-x86_64.mak b/config-x86_64.mak
index bb8ee89..a9a2a9e 100644
--- a/config-x86_64.mak
+++ b/config-x86_64.mak
@@ -7,7 +7,7 @@ CFLAGS += -D__x86_64__
tests = $(TEST_DIR)/access.flat $(TEST_DIR)/apic.flat \
$(TEST_DIR)/emulator.flat $(TEST_DIR)/idt_test.flat \
$(TEST_DIR)/xsave.flat $(TEST_DIR)/rmap_chain.flat \
- $(TEST_DIR)/pcid.flat
+ $(TEST_DIR)/pcid.flat $(TEST_DIR)/debug.flat
tests += $(TEST_DIR)/svm.flat
tests += $(TEST_DIR)/vmx.flat
diff --git a/lib/x86/desc.h b/lib/x86/desc.h
index 5c850b2..b795aad 100644
--- a/lib/x86/desc.h
+++ b/lib/x86/desc.h
@@ -66,6 +66,8 @@ typedef struct {
".popsection \n\t" \
"1111:"
+#define DB_VECTOR 1
+#define BP_VECTOR 3
#define UD_VECTOR 6
#define GP_VECTOR 13
diff --git a/x86/debug.c b/x86/debug.c
new file mode 100644
index 0000000..154c7fe
--- /dev/null
+++ b/x86/debug.c
@@ -0,0 +1,113 @@
+/*
+ * Test for x86 debugging facilities
+ *
+ * Copyright (c) Siemens AG, 2014
+ *
+ * Authors:
+ * Jan Kiszka <jan.kiszka@xxxxxxxxxxx>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.
+ */
+
+#include "libcflat.h"
+#include "desc.h"
+
+static volatile unsigned long bp_addr[10], dr6[10];
+static volatile unsigned int n;
+static volatile unsigned long value;
+
+static unsigned long get_dr6(void)
+{
+ unsigned long value;
+
+ asm volatile("mov %%dr6,%0" : "=r" (value));
+ return value;
+}
+
+static void set_dr0(void *value)
+{
+ asm volatile("mov %0,%%dr0" : : "r" (value));
+}
+
+static void set_dr1(void *value)
+{
+ asm volatile("mov %0,%%dr1" : : "r" (value));
+}
+
+static void set_dr7(unsigned long value)
+{
+ asm volatile("mov %0,%%dr7" : : "r" (value));
+}
+
+static void handle_db(struct ex_regs *regs)
+{
+ bp_addr[n] = regs->rip;
+ dr6[n] = get_dr6();
+
+ if (dr6[n] & 0x1)
+ regs->rflags |= (1 << 16);
+
+ if (++n >= 10) {
+ regs->rflags &= ~(1 << 8);
+ set_dr7(0x00000400);
+ }
+}
+
+static void handle_bp(struct ex_regs *regs)
+{
+ bp_addr[0] = regs->rip;
+}
+
+int main(int ac, char **av)
+{
+ unsigned long start;
+
+ setup_idt();
+ handle_exception(DB_VECTOR, handle_db);
+ handle_exception(BP_VECTOR, handle_bp);
+
+sw_bp:
+ asm volatile("int3");
+ report("#BP", bp_addr[0] == (unsigned long)&&sw_bp + 1);
+
+ set_dr0(&&hw_bp);
+ set_dr7(0x00000402);
+hw_bp:
+ asm volatile("nop");
+ report("hw breakpoint",
+ n == 1 &&
+ bp_addr[0] == ((unsigned long)&&hw_bp) && dr6[0] == 0xffff0ff1);
+
+ n = 0;
+ asm volatile(
+ "pushf\n\t"
+ "pop %%rax\n\t"
+ "or $(1<<8),%%rax\n\t"
+ "push %%rax\n\t"
+ "lea (%%rip),%0\n\t"
+ "popf\n\t"
+ "and $~(1<<8),%%rax\n\t"
+ "push %%rax\n\t"
+ "popf\n\t"
+ : "=g" (start) : : "rax");
+ report("single step",
+ n == 3 &&
+ bp_addr[0] == start+1+6 && dr6[0] == 0xffff4ff0 &&
+ bp_addr[1] == start+1+6+1 && dr6[1] == 0xffff4ff0 &&
+ bp_addr[2] == start+1+6+1+1 && dr6[2] == 0xffff4ff0);
+
+ n = 0;
+ set_dr1((void *)&value);
+ set_dr7(0x00d0040a);
+
+ asm volatile(
+ "mov $42,%%rax\n\t"
+ "mov %%rax,%0\n\t"
+ : "=m" (value) : : "rax");
+hw_wp:
+ report("hw watchpoint",
+ n == 1 &&
+ bp_addr[0] == ((unsigned long)&&hw_wp) && dr6[0] == 0xffff4ff2);
+
+ return 0;
+}
diff --git a/x86/unittests.cfg b/x86/unittests.cfg
index 85c36aa..7930c02 100644
--- a/x86/unittests.cfg
+++ b/x86/unittests.cfg
@@ -155,3 +155,6 @@ file = vmx.flat
extra_params = -cpu host,+vmx
arch = x86_64
+[debug]
+file = debug.flag
+arch = x86_64
--
1.8.1.1.298.ge7eed54
--
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