kgdbts: Use HW breakpoints with CONFIG_DEBUG_RODATA
Whenever CONFIG_DEBUG_RODATA is set in the kernel config many kernel
text sections become read-only, and the use of software breakpoints in
the kgdb tests will cause the kernel to fail to complete the start up.
Until such time that there is an official API for modifying read-only
text sections hardware breakpoints must be used to run the do_fork or
sys_open tests or the tests get skipped.
Also fix the duplicated include reported by:
Huang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
diff --git a/drivers/misc/kgdbts.c b/drivers/misc/kgdbts.c
index 2763ae0..e4ff50b 100644
--- a/drivers/misc/kgdbts.c
+++ b/drivers/misc/kgdbts.c
@@ -102,7 +102,6 @@
#include <linux/nmi.h>
#include <linux/delay.h>
#include <linux/kthread.h>
-#include <linux/delay.h>
#define v1printk(a...) do { \
if (verbose) \
@@ -130,6 +129,8 @@
static int test_complete;
static int send_ack;
static int final_ack;
+static int force_hwbrks;
+static int hwbreaks_ok;
static int hw_break_val;
static int hw_break_val2;
#if defined(CONFIG_ARM) || defined(CONFIG_MIPS) || defined(CONFIG_SPARC)
@@ -233,12 +234,12 @@
static void sw_break(char *arg)
{
- break_helper("Z0", arg, 0);
+ break_helper(force_hwbrks ? "Z1" : "Z0", arg, 0);
}
static void sw_rem_break(char *arg)
{
- break_helper("z0", arg, 0);
+ break_helper(force_hwbrks ? "z1" : "z0", arg, 0);
}
static void hw_break(char *arg)
@@ -780,6 +781,8 @@
return;
eprintk("kgdbts: ERROR %s test failed\n", ts.name);
+ if (is_hw_breakpoint)
+ hwbreaks_ok = 0;
}
static void run_hw_break_test(int is_write_test)
@@ -797,9 +800,11 @@
kgdb_breakpoint();
hw_break_val_access();
if (is_write_test) {
- if (test_complete == 2)
+ if (test_complete == 2) {
eprintk("kgdbts: ERROR %s broke on access\n",
ts.name);
+ hwbreaks_ok = 0;
+ }
hw_break_val_write();
}
kgdb_breakpoint();
@@ -808,6 +813,7 @@
return;
eprintk("kgdbts: ERROR %s test failed\n", ts.name);
+ hwbreaks_ok = 0;
}
static void run_nmi_sleep_test(int nmi_sleep)
@@ -911,6 +917,7 @@
/* All HW break point tests */
if (arch_kgdb_ops.flags & KGDB_HW_BREAKPOINT) {
+ hwbreaks_ok = 1;
v1printk("kgdbts:RUN hw breakpoint test\n");
run_breakpoint_test(1);
v1printk("kgdbts:RUN hw write breakpoint test\n");
@@ -924,6 +931,19 @@
run_nmi_sleep_test(nmi_sleep);
}
+#ifdef CONFIG_DEBUG_RODATA
+ /* Until there is an api to write to read-only text segments, use
+ * HW breakpoints for the remainder of any tests, else print a
+ * failure message if hw breakpoints do not work.
+ */
+ if (!(arch_kgdb_ops.flags & KGDB_HW_BREAKPOINT && hwbreaks_ok)) {
+ eprintk("kgdbts: HW breakpoints do not work,"
+ "skipping remaining tests\n");
+ return;
+ }
+ force_hwbrks = 1;
+#endif /* CONFIG_DEBUG_RODATA */
+
/* If the do_fork test is run it will be the last test that is
* executed because a kernel thread will be spawned at the very
* end to unregister the debug hooks.
