mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-22 13:29:57 +07:00
76ed0b803a
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: 834b2964b7 ("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>
108 lines
2.7 KiB
C
108 lines
2.7 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
/*
|
|
* ARM KGDB support
|
|
*
|
|
* Author: Deepak Saxena <dsaxena@mvista.com>
|
|
*
|
|
* Copyright (C) 2002 MontaVista Software Inc.
|
|
*
|
|
*/
|
|
|
|
#ifndef __ARM_KGDB_H__
|
|
#define __ARM_KGDB_H__
|
|
|
|
#include <linux/ptrace.h>
|
|
#include <asm/opcodes.h>
|
|
|
|
/*
|
|
* GDB assumes that we're a user process being debugged, so
|
|
* it will send us an SWI command to write into memory as the
|
|
* debug trap. When an SWI occurs, the next instruction addr is
|
|
* placed into R14_svc before jumping to the vector trap.
|
|
* This doesn't work for kernel debugging as we are already in SVC
|
|
* we would loose the kernel's LR, which is a bad thing. This
|
|
* is bad thing.
|
|
*
|
|
* By doing this as an undefined instruction trap, we force a mode
|
|
* switch from SVC to UND mode, allowing us to save full kernel state.
|
|
*
|
|
* We also define a KGDB_COMPILED_BREAK which can be used to compile
|
|
* in breakpoints. This is important for things like sysrq-G and for
|
|
* the initial breakpoint from trap_init().
|
|
*
|
|
* Note to ARM HW designers: Add real trap support like SH && PPC to
|
|
* make our lives much much simpler. :)
|
|
*/
|
|
#define BREAK_INSTR_SIZE 4
|
|
#define GDB_BREAKINST 0xef9f0001
|
|
#define KGDB_BREAKINST 0xe7ffdefe
|
|
#define KGDB_COMPILED_BREAK 0xe7ffdeff
|
|
#define CACHE_FLUSH_IS_SAFE 1
|
|
|
|
#ifndef __ASSEMBLY__
|
|
|
|
static inline void arch_kgdb_breakpoint(void)
|
|
{
|
|
asm(__inst_arm(0xe7ffdeff));
|
|
}
|
|
|
|
extern void kgdb_handle_bus_error(void);
|
|
extern int kgdb_fault_expected;
|
|
|
|
#endif /* !__ASSEMBLY__ */
|
|
|
|
/*
|
|
* From Kevin Hilman:
|
|
*
|
|
* gdb is expecting the following registers layout.
|
|
*
|
|
* r0-r15: 1 long word each
|
|
* f0-f7: unused, 3 long words each !!
|
|
* fps: unused, 1 long word
|
|
* cpsr: 1 long word
|
|
*
|
|
* Even though f0-f7 and fps are not used, they need to be
|
|
* present in the registers sent for correct processing in
|
|
* the host-side gdb.
|
|
*
|
|
* In particular, it is crucial that CPSR is in the right place,
|
|
* otherwise gdb will not be able to correctly interpret stepping over
|
|
* conditional branches.
|
|
*/
|
|
#define _GP_REGS 16
|
|
#define _FP_REGS 8
|
|
#define _EXTRA_REGS 2
|
|
#define GDB_MAX_REGS (_GP_REGS + (_FP_REGS * 3) + _EXTRA_REGS)
|
|
#define DBG_MAX_REG_NUM (_GP_REGS + _FP_REGS + _EXTRA_REGS)
|
|
|
|
#define KGDB_MAX_NO_CPUS 1
|
|
#define BUFMAX 400
|
|
#define NUMREGBYTES (GDB_MAX_REGS << 2)
|
|
#define NUMCRITREGBYTES (32 << 2)
|
|
|
|
#define _R0 0
|
|
#define _R1 1
|
|
#define _R2 2
|
|
#define _R3 3
|
|
#define _R4 4
|
|
#define _R5 5
|
|
#define _R6 6
|
|
#define _R7 7
|
|
#define _R8 8
|
|
#define _R9 9
|
|
#define _R10 10
|
|
#define _FP 11
|
|
#define _IP 12
|
|
#define _SPT 13
|
|
#define _LR 14
|
|
#define _PC 15
|
|
#define _CPSR (GDB_MAX_REGS - 1)
|
|
|
|
/*
|
|
* So that we can denote the end of a frame for tracing,
|
|
* in the simple case:
|
|
*/
|
|
#define CFI_END_FRAME(func) __CFI_END_FRAME(_PC, _SPT, func)
|
|
|
|
#endif /* __ASM_KGDB_H__ */
|