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[S390] kprobes: jprobe save and restore

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Register %r14 and %r15 are already stored in jprobe_saved_regs, no need
to store them a second time in jprobe_saved_r14 / jprobe_saved_r15.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Martin Schwidefsky 2011-01-05 12:47:22 +01:00 committed by Martin Schwidefsky
parent 371db06b01
commit 92b8cbf17a
2 changed files with 8 additions and 13 deletions
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4
arch/s390/include/asm/kprobes.h
View File

@ -70,10 +70,8 @@ struct kprobe_ctlblk {
unsigned long kprobe_status;
unsigned long kprobe_saved_imask;
unsigned long kprobe_saved_ctl[3];
struct pt_regs jprobe_saved_regs;
unsigned long jprobe_saved_r14;
unsigned long jprobe_saved_r15;
struct prev_kprobe prev_kprobe;
struct pt_regs jprobe_saved_regs;
kprobe_opcode_t jprobes_stack[MAX_STACK_SIZE];
};

17
arch/s390/kernel/kprobes.c
View File

@ -585,8 +585,8 @@ int __kprobes kprobe_exceptions_notify(struct notifier_block *self,
int __kprobes setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
{
struct jprobe *jp = container_of(p, struct jprobe, kp);
unsigned long addr;
struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
unsigned long stack;
memcpy(&kcb->jprobe_saved_regs, regs, sizeof(struct pt_regs));
@ -594,14 +594,10 @@ int __kprobes setjmp_pre_handler(struct kprobe *p, struct pt_regs *regs)
regs->psw.addr = (unsigned long)(jp->entry) | PSW_ADDR_AMODE;
regs->psw.mask &= ~(PSW_MASK_IO | PSW_MASK_EXT);
/* r14 is the function return address */
kcb->jprobe_saved_r14 = (unsigned long)regs->gprs[14];
/* r15 is the stack pointer */
kcb->jprobe_saved_r15 = (unsigned long)regs->gprs[15];
addr = (unsigned long)kcb->jprobe_saved_r15;
stack = (unsigned long) regs->gprs[15];
memcpy(kcb->jprobes_stack, (kprobe_opcode_t *) addr,
MIN_STACK_SIZE(addr));
memcpy(kcb->jprobes_stack, (void *) stack, MIN_STACK_SIZE(stack));
return 1;
}
@ -618,13 +614,14 @@ void __kprobes jprobe_return_end(void)
int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
{
struct kprobe_ctlblk *kcb = get_kprobe_ctlblk();
unsigned long stack_addr = (unsigned long)(kcb->jprobe_saved_r15);
unsigned long stack;
stack = (unsigned long) kcb->jprobe_saved_regs.gprs[15];
/* Put the regs back */
memcpy(regs, &kcb->jprobe_saved_regs, sizeof(struct pt_regs));
/* put the stack back */
memcpy((kprobe_opcode_t *) stack_addr, kcb->jprobes_stack,
MIN_STACK_SIZE(stack_addr));
memcpy((void *) stack, kcb->jprobes_stack, MIN_STACK_SIZE(stack));
preempt_enable_no_resched();
return 1;
}