[PATCH] Kprobes: prevent possible race conditions sparc64 changes

This patch contains the sparc64 architecture specific changes to prevent the
possible race conditions.

Signed-off-by: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Prasanna S Panchamukhi 2005-09-06 15:19:30 -07:00 committed by Linus Torvalds
parent 1f7ad57b75
commit 05e14cb3ba
5 changed files with 30 additions and 20 deletions

View File

@ -8,6 +8,7 @@
#include <linux/kprobes.h>
#include <asm/kdebug.h>
#include <asm/signal.h>
#include <asm/cacheflush.h>
/* We do not have hardware single-stepping on sparc64.
* So we implement software single-stepping with breakpoint
@ -37,31 +38,31 @@
* - Mark that we are no longer actively in a kprobe.
*/
int arch_prepare_kprobe(struct kprobe *p)
int __kprobes arch_prepare_kprobe(struct kprobe *p)
{
return 0;
}
void arch_copy_kprobe(struct kprobe *p)
void __kprobes arch_copy_kprobe(struct kprobe *p)
{
p->ainsn.insn[0] = *p->addr;
p->ainsn.insn[1] = BREAKPOINT_INSTRUCTION_2;
p->opcode = *p->addr;
}
void arch_arm_kprobe(struct kprobe *p)
void __kprobes arch_arm_kprobe(struct kprobe *p)
{
*p->addr = BREAKPOINT_INSTRUCTION;
flushi(p->addr);
}
void arch_disarm_kprobe(struct kprobe *p)
void __kprobes arch_disarm_kprobe(struct kprobe *p)
{
*p->addr = p->opcode;
flushi(p->addr);
}
void arch_remove_kprobe(struct kprobe *p)
void __kprobes arch_remove_kprobe(struct kprobe *p)
{
}
@ -111,7 +112,7 @@ static inline void prepare_singlestep(struct kprobe *p, struct pt_regs *regs)
}
}
static int kprobe_handler(struct pt_regs *regs)
static int __kprobes kprobe_handler(struct pt_regs *regs)
{
struct kprobe *p;
void *addr = (void *) regs->tpc;
@ -191,8 +192,9 @@ no_kprobe:
* The original INSN location was REAL_PC, it actually
* executed at PC and produced destination address NPC.
*/
static unsigned long relbranch_fixup(u32 insn, unsigned long real_pc,
unsigned long pc, unsigned long npc)
static unsigned long __kprobes relbranch_fixup(u32 insn, unsigned long real_pc,
unsigned long pc,
unsigned long npc)
{
/* Branch not taken, no mods necessary. */
if (npc == pc + 0x4UL)
@ -217,7 +219,8 @@ static unsigned long relbranch_fixup(u32 insn, unsigned long real_pc,
/* If INSN is an instruction which writes it's PC location
* into a destination register, fix that up.
*/
static void retpc_fixup(struct pt_regs *regs, u32 insn, unsigned long real_pc)
static void __kprobes retpc_fixup(struct pt_regs *regs, u32 insn,
unsigned long real_pc)
{
unsigned long *slot = NULL;
@ -257,7 +260,7 @@ static void retpc_fixup(struct pt_regs *regs, u32 insn, unsigned long real_pc)
* This function prepares to return from the post-single-step
* breakpoint trap.
*/
static void resume_execution(struct kprobe *p, struct pt_regs *regs)
static void __kprobes resume_execution(struct kprobe *p, struct pt_regs *regs)
{
u32 insn = p->ainsn.insn[0];
@ -315,8 +318,8 @@ static inline int kprobe_fault_handler(struct pt_regs *regs, int trapnr)
/*
* Wrapper routine to for handling exceptions.
*/
int kprobe_exceptions_notify(struct notifier_block *self, unsigned long val,
void *data)
int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
unsigned long val, void *data)
{
struct die_args *args = (struct die_args *)data;
switch (val) {
@ -344,7 +347,8 @@ int kprobe_exceptions_notify(struct notifier_block *self, unsigned long val,
return NOTIFY_DONE;
}
asmlinkage void kprobe_trap(unsigned long trap_level, struct pt_regs *regs)
asmlinkage void __kprobes kprobe_trap(unsigned long trap_level,
struct pt_regs *regs)
{
BUG_ON(trap_level != 0x170 && trap_level != 0x171);
@ -368,7 +372,7 @@ static struct pt_regs jprobe_saved_regs;
static struct pt_regs *jprobe_saved_regs_location;
static struct sparc_stackf jprobe_saved_stack;
int setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
int __kprobes setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
{
struct jprobe *jp = container_of(p, struct jprobe, kp);
@ -390,7 +394,7 @@ int setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
return 1;
}
void jprobe_return(void)
void __kprobes jprobe_return(void)
{
preempt_enable_no_resched();
__asm__ __volatile__(
@ -403,7 +407,7 @@ extern void jprobe_return_trap_instruction(void);
extern void __show_regs(struct pt_regs * regs);
int longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
{
u32 *addr = (u32 *) regs->tpc;

View File

@ -17,6 +17,7 @@ SECTIONS
*(.text)
SCHED_TEXT
LOCK_TEXT
KPROBES_TEXT
*(.gnu.warning)
} =0
_etext = .;

View File

@ -18,6 +18,7 @@
#include <linux/smp_lock.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/kprobes.h>
#include <asm/page.h>
#include <asm/pgtable.h>
@ -117,8 +118,9 @@ unsigned long __init prom_probe_memory (void)
return tally;
}
static void unhandled_fault(unsigned long address, struct task_struct *tsk,
struct pt_regs *regs)
static void __kprobes unhandled_fault(unsigned long address,
struct task_struct *tsk,
struct pt_regs *regs)
{
if ((unsigned long) address < PAGE_SIZE) {
printk(KERN_ALERT "Unable to handle kernel NULL "
@ -304,7 +306,7 @@ cannot_handle:
unhandled_fault (address, current, regs);
}
asmlinkage void do_sparc64_fault(struct pt_regs *regs)
asmlinkage void __kprobes do_sparc64_fault(struct pt_regs *regs)
{
struct mm_struct *mm = current->mm;
struct vm_area_struct *vma;

View File

@ -19,6 +19,7 @@
#include <linux/pagemap.h>
#include <linux/fs.h>
#include <linux/seq_file.h>
#include <linux/kprobes.h>
#include <asm/head.h>
#include <asm/system.h>
@ -250,7 +251,7 @@ out:
put_cpu();
}
void flush_icache_range(unsigned long start, unsigned long end)
void __kprobes flush_icache_range(unsigned long start, unsigned long end)
{
/* Cheetah has coherent I-cache. */
if (tlb_type == spitfire) {

View File

@ -119,6 +119,7 @@ __spitfire_flush_tlb_mm_slow:
#else
#error unsupported PAGE_SIZE
#endif
.section .kprobes.text
.align 32
.globl __flush_icache_page
__flush_icache_page: /* %o0 = phys_page */
@ -201,6 +202,7 @@ dflush4:stxa %g0, [%o4] ASI_DCACHE_TAG
nop
#endif /* DCACHE_ALIASING_POSSIBLE */
.previous .text
.align 32
__prefill_dtlb:
rdpr %pstate, %g7