ARM: 8764/1: kgdb: fix NUMREGBYTES so that gdb_regs[] is the correct size

BugLink: http://bugs.launchpad.net/bugs/1807469
commit 76ed0b803a2ab793a1b27d1dfe0de7955282cd34 upstream.

NUMREGBYTES (which is used as the size for gdb_regs[]) is incorrectly
based on DBG_MAX_REG_NUM instead of GDB_MAX_REGS. DBG_MAX_REG_NUM
is the number of total registers, while GDB_MAX_REGS is the number
of 'unsigned longs' it takes to serialize those registers. Since
FP registers require 3 'unsigned longs' each, DBG_MAX_REG_NUM is
smaller than GDB_MAX_REGS.

This causes GDB 8.0 give the following error on connect:
"Truncated register 19 in remote 'g' packet"

This also causes the register serialization/deserialization logic
to overflow gdb_regs[], overwriting whatever follows.

Fixes: 834b2964b7ab ("kgdb,arm: fix register dump")
Cc: <stable@vger.kernel.org> # 2.6.37+
Signed-off-by: David Rivshin <drivshin@allworx.com>
Acked-by: Rabin Vincent <rabin@rab.in>
Tested-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

diff --git a/arch/arm/include/asm/kgdb.h b/arch/arm/include/asm/kgdb.h
index 3b73fdcf3627af25207be6df16be69ac7a95ea0f..8de1100d1067453e39ed1858b9f140e4bae61773 100644 (file)
--- a/arch/arm/include/asm/kgdb.h
+++ b/arch/arm/include/asm/kgdb.h
@@ -77,7 +77,7 @@ extern int kgdb_fault_expected;
 
 #define KGDB_MAX_NO_CPUS       1
 #define BUFMAX                 400
-#define NUMREGBYTES            (DBG_MAX_REG_NUM << 2)
+#define NUMREGBYTES            (GDB_MAX_REGS << 2)
 #define NUMCRITREGBYTES                (32 << 2)
 
 #define _R0                    0