Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb:
  kgdbts: Use HW breakpoints with CONFIG_DEBUG_RODATA
  kgdb: use common ascii helpers and put_unaligned_be32 helper

2 files changed, 32 insertions, 17 deletions

diff --git a/drivers/misc/kgdbts.c b/drivers/misc/kgdbts.c
index fa394104339c..e4ff50b95a5e 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) \
@@ -119,7 +118,6 @@
         } while (0)
 #define MAX_CONFIG_LEN          40
 
-static const char hexchars[] = "0123456789abcdef";
 static struct kgdb_io kgdbts_io_ops;
 static char get_buf[BUFMAX];
 static int get_buf_cnt;
@@ -131,6 +129,8 @@ static int repeat_test;
 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)
@@ -234,12 +234,12 @@ static void break_helper(char *bp_type, char *arg, unsigned long vaddr)
 
 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)
@@ -619,8 +619,8 @@ static void fill_get_buf(char *buf)
                 count++;
         }
         strcat(get_buf, "#");
-        get_buf[count + 2] = hexchars[checksum >> 4];
-        get_buf[count + 3] = hexchars[checksum & 0xf];
+        get_buf[count + 2] = hex_asc_hi(checksum);
+        get_buf[count + 3] = hex_asc_lo(checksum);
         get_buf[count + 4] = '\0';
         v2printk("get%i: %s\n", ts.idx, get_buf);
 }
@@ -781,6 +781,8 @@ static void run_breakpoint_test(int is_hw_breakpoint)
                 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)
@@ -798,9 +800,11 @@ static void run_hw_break_test(int is_write_test)
         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();
@@ -809,6 +813,7 @@ static void run_hw_break_test(int is_write_test)
                 return;
 
         eprintk("kgdbts: ERROR %s test failed\n", ts.name);
+        hwbreaks_ok = 0;
 }
 
 static void run_nmi_sleep_test(int nmi_sleep)
@@ -912,6 +917,7 @@ static void kgdbts_run_tests(void)
 
         /* 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");
@@ -925,6 +931,19 @@ static void kgdbts_run_tests(void)
                 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.
diff --git a/kernel/kgdb.c b/kernel/kgdb.c
index 14787de568b3..79e3c90113c2 100644
--- a/kernel/kgdb.c
+++ b/kernel/kgdb.c
@@ -52,6 +52,7 @@
 #include <asm/byteorder.h>
 #include <asm/atomic.h>
 #include <asm/system.h>
+#include <asm/unaligned.h>
 
 static int kgdb_break_asap;
 
@@ -227,8 +228,6 @@ void __weak kgdb_disable_hw_debug(struct pt_regs *regs)
  * GDB remote protocol parser:
  */
 
-static const char       hexchars[] = "0123456789abcdef";
-
 static int hex(char ch)
 {
         if ((ch >= 'a') && (ch <= 'f'))
@@ -316,8 +315,8 @@ static void put_packet(char *buffer)
                 }
 
                 kgdb_io_ops->write_char('#');
-                kgdb_io_ops->write_char(hexchars[checksum >> 4]);
-                kgdb_io_ops->write_char(hexchars[checksum & 0xf]);
+                kgdb_io_ops->write_char(hex_asc_hi(checksum));
+                kgdb_io_ops->write_char(hex_asc_lo(checksum));
                 if (kgdb_io_ops->flush)
                         kgdb_io_ops->flush();
 
@@ -478,8 +477,8 @@ static void error_packet(char *pkt, int error)
 {
         error = -error;
         pkt[0] = 'E';
-        pkt[1] = hexchars[(error / 10)];
-        pkt[2] = hexchars[(error % 10)];
+        pkt[1] = hex_asc[(error / 10)];
+        pkt[2] = hex_asc[(error % 10)];
         pkt[3] = '\0';
 }
 
@@ -510,10 +509,7 @@ static void int_to_threadref(unsigned char *id, int value)
         scan = (unsigned char *)id;
         while (i--)
                 *scan++ = 0;
-        *scan++ = (value >> 24) & 0xff;
-        *scan++ = (value >> 16) & 0xff;
-        *scan++ = (value >> 8) & 0xff;
-        *scan++ = (value & 0xff);
+        put_unaligned_be32(value, scan);
 }
 
 static struct task_struct *getthread(struct pt_regs *regs, int tid)