kgdb: x86: Return all segment registers also in 64-bit mode

Even if the content is always 0, gdb expects us to return also ds,
es, fs, and gs while in x86-64 mode. Do this to avoid ugly errors on
"info registers".

[jason.wessel@windriver.com: adjust NUMREGBYTES for two new regs]
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>

2 files changed, 11 insertions, 5 deletions

diff --git a/arch/x86/include/asm/kgdb.h b/arch/x86/include/asm/kgdb.h
index 77e95f54570a..332f98c9111f 100644
--- a/arch/x86/include/asm/kgdb.h
+++ b/arch/x86/include/asm/kgdb.h
@@ -64,11 +64,15 @@ enum regnames {
         GDB_PS,                 /* 17 */
         GDB_CS,                 /* 18 */
         GDB_SS,                 /* 19 */
+        GDB_DS,                 /* 20 */
+        GDB_ES,                 /* 21 */
+        GDB_FS,                 /* 22 */
+        GDB_GS,                 /* 23 */
 };
 #define GDB_ORIG_AX             57
-#define DBG_MAX_REG_NUM         20
-/* 17 64 bit regs and 3 32 bit regs */
-#define NUMREGBYTES             ((17 * 8) + (3 * 4))
+#define DBG_MAX_REG_NUM         24
+/* 17 64 bit regs and 5 32 bit regs */
+#define NUMREGBYTES             ((17 * 8) + (5 * 4))
 #endif /* ! CONFIG_X86_32 */
 
 static inline void arch_kgdb_breakpoint(void)
diff --git a/arch/x86/kernel/kgdb.c b/arch/x86/kernel/kgdb.c
index faba5771acad..fdc37b3d0ce3 100644
--- a/arch/x86/kernel/kgdb.c
+++ b/arch/x86/kernel/kgdb.c
@@ -67,8 +67,6 @@ struct dbg_reg_def_t dbg_reg_def[DBG_MAX_REG_NUM] =
         { "ss", 4, offsetof(struct pt_regs, ss) },
         { "ds", 4, offsetof(struct pt_regs, ds) },
         { "es", 4, offsetof(struct pt_regs, es) },
-        { "fs", 4, -1 },
-        { "gs", 4, -1 },
 #else
         { "ax", 8, offsetof(struct pt_regs, ax) },
         { "bx", 8, offsetof(struct pt_regs, bx) },
@@ -90,7 +88,11 @@ struct dbg_reg_def_t dbg_reg_def[DBG_MAX_REG_NUM] =
         { "flags", 4, offsetof(struct pt_regs, flags) },
         { "cs", 4, offsetof(struct pt_regs, cs) },
         { "ss", 4, offsetof(struct pt_regs, ss) },
+        { "ds", 4, -1 },
+        { "es", 4, -1 },
 #endif
+        { "fs", 4, -1 },
+        { "gs", 4, -1 },
 };
 
 int dbg_set_reg(int regno, void *mem, struct pt_regs *regs)