Commit 1f666587 authored by Paul Mundt's avatar Paul Mundt
Browse files

sh: Fix exception_handling_table alignment. 



With the recent change ripping out interrupt_table, explicit
padding of the table was missing, causing bad things to happen
when manually inserting handlers in to the table. This problem
particularly showed up in relation to do_fpu_state_restore()
which was inserted quite deeply in to the table and ended up
scribbling over a slab object.

Signed-off-by: default avatarPaul Mundt <lethal@linux-sh.org>
parent 082c44d2

arch/sh/kernel/cpu/sh3/ex.S

+8 −1
Original line number Diff line number Diff line
@@ -4,7 +4,7 @@ 
 *  The SH-3 exception vector table.



 *  Copyright (C) 1999, 2000, 2002  Niibe Yutaka

 *  Copyright (C) 2003  Paul Mundt

 *  Copyright (C) 2003 - 2006  Paul Mundt

 *

 * This file is subject to the terms and conditions of the GNU General Public

 * License.  See the file "COPYING" in the main directory of this archive
@@ -49,3 +49,10 @@ ENTRY(nmi_slot) 
#endif

ENTRY(user_break_point_trap)

	.long	break_point_trap	/* 1E0 */



	/*

	 * Pad the remainder of the table out, exceptions residing in far

	 * away offsets can be manually inserted in to their appropriate

	 * location via set_exception_table_{evt,vec}().

	 */

	.balign 4096,0,4096

arch/sh/kernel/cpu/sh4/ex.S

+8 −1
Original line number Diff line number Diff line
@@ -4,7 +4,7 @@ 
 *  The SH-4 exception vector table.



 *  Copyright (C) 1999, 2000, 2002  Niibe Yutaka

 *  Copyright (C) 2003  Paul Mundt

 *  Copyright (C) 2003 - 2006  Paul Mundt

 *

 * This file is subject to the terms and conditions of the GNU General Public

 * License.  See the file "COPYING" in the main directory of this archive
@@ -53,3 +53,10 @@ ENTRY(nmi_slot) 
#endif

ENTRY(user_break_point_trap)

	.long	break_point_trap	/* 1E0 */



	/*

	 * Pad the remainder of the table out, exceptions residing in far

	 * away offsets can be manually inserted in to their appropriate

	 * location via set_exception_table_{evt,vec}().

	 */

	.balign	4096,0,4096

arch/sh/kernel/traps.c

+21 −22
Original line number Diff line number Diff line
@@ -11,27 +11,15 @@ 
 * License.  See the file "COPYING" in the main directory of this archive

 * for more details.

 */

#include <linux/sched.h>

#include <linux/kernel.h>

#include <linux/string.h>

#include <linux/errno.h>

#include <linux/ptrace.h>

#include <linux/timer.h>

#include <linux/mm.h>

#include <linux/smp.h>

#include <linux/smp_lock.h>

#include <linux/init.h>

#include <linux/delay.h>

#include <linux/spinlock.h>

#include <linux/module.h>

#include <linux/kallsyms.h>



#include <linux/io.h>

#include <asm/system.h>

#include <asm/uaccess.h>

#include <asm/io.h>

#include <asm/atomic.h>

#include <asm/processor.h>

#include <asm/sections.h>



#ifdef CONFIG_SH_KGDB

#include <asm/kgdb.h>
@@ -581,7 +569,10 @@ int is_dsp_inst(struct pt_regs *regs) 
#define is_dsp_inst(regs)	(0)

#endif /* CONFIG_SH_DSP */



/* arch/sh/kernel/cpu/sh4/fpu.c */

extern int do_fpu_inst(unsigned short, struct pt_regs *);

extern asmlinkage void do_fpu_state_restore(unsigned long r4, unsigned long r5,

		unsigned long r6, unsigned long r7, struct pt_regs regs);



asmlinkage void do_reserved_inst(unsigned long r4, unsigned long r5,

				unsigned long r6, unsigned long r7,
@@ -740,14 +731,20 @@ void __init per_cpu_trap_init(void) 
		     : "memory");

}



void __init trap_init(void)

void *set_exception_table_vec(unsigned int vec, void *handler)

{

	extern void *exception_handling_table[];

	void *old_handler;

	

	old_handler = exception_handling_table[vec];

	exception_handling_table[vec] = handler;

	return old_handler;

}



	exception_handling_table[TRAP_RESERVED_INST]

		= (void *)do_reserved_inst;

	exception_handling_table[TRAP_ILLEGAL_SLOT_INST]

		= (void *)do_illegal_slot_inst;

void __init trap_init(void)

{

	set_exception_table_vec(TRAP_RESERVED_INST, do_reserved_inst);

	set_exception_table_vec(TRAP_ILLEGAL_SLOT_INST, do_illegal_slot_inst);



#if defined(CONFIG_CPU_SH4) && !defined(CONFIG_SH_FPU) || \

    defined(CONFIG_SH_FPU_EMU)
@@ -756,9 +753,11 @@ void __init trap_init(void) 
	 * reserved. They'll be handled in the math-emu case, or faulted on

	 * otherwise.

	 */

	/* entry 64 corresponds to EXPEVT=0x800 */

	exception_handling_table[64] = (void *)do_reserved_inst;

	exception_handling_table[65] = (void *)do_illegal_slot_inst;

	set_exception_table_evt(0x800, do_reserved_inst);

	set_exception_table_evt(0x820, do_illegal_slot_inst);

#elif defined(CONFIG_SH_FPU)

	set_exception_table_evt(0x800, do_fpu_state_restore);

	set_exception_table_evt(0x820, do_fpu_state_restore);

#endif

		

	/* Setup VBR for boot cpu */

include/asm-sh/system.h

+7 −0
Original line number Diff line number Diff line
@@ -353,6 +353,13 @@ static inline unsigned long __cmpxchg(volatile void * ptr, unsigned long old, 
				    (unsigned long)_n_, sizeof(*(ptr))); \

  })



extern void *set_exception_table_vec(unsigned int vec, void *handler);



static inline void *set_exception_table_evt(unsigned int evt, void *handler)

{

	return set_exception_table_vec(evt >> 5, handler);

}



/* XXX

 * disable hlt during certain critical i/o operations

 */

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