diff options
| -rw-r--r-- | arch/ia64/kernel/kprobes.c | 48 |
1 files changed, 43 insertions, 5 deletions
diff --git a/arch/ia64/kernel/kprobes.c b/arch/ia64/kernel/kprobes.c index 45b8479c986..789881ca83d 100644 --- a/arch/ia64/kernel/kprobes.c +++ b/arch/ia64/kernel/kprobes.c @@ -34,6 +34,7 @@ #include <asm/pgtable.h> #include <asm/kdebug.h> #include <asm/sections.h> +#include <asm/uaccess.h> extern void jprobe_inst_return(void); @@ -722,13 +723,50 @@ static int __kprobes kprobes_fault_handler(struct pt_regs *regs, int trapnr) struct kprobe *cur = kprobe_running(); struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); - if (cur->fault_handler && cur->fault_handler(cur, regs, trapnr)) - return 1; - if (kcb->kprobe_status & KPROBE_HIT_SS) { - resume_execution(cur, regs); - reset_current_kprobe(); + switch(kcb->kprobe_status) { + case KPROBE_HIT_SS: + case KPROBE_REENTER: + /* + * We are here because the instruction being single + * stepped caused a page fault. We reset the current + * kprobe and the instruction pointer points back to + * the probe address and allow the page fault handler + * to continue as a normal page fault. + */ + regs->cr_iip = ((unsigned long)cur->addr) & ~0xFULL; + ia64_psr(regs)->ri = ((unsigned long)cur->addr) & 0xf; + if (kcb->kprobe_status == KPROBE_REENTER) + restore_previous_kprobe(kcb); + else + reset_current_kprobe(); preempt_enable_no_resched(); + break; + case KPROBE_HIT_ACTIVE: + case KPROBE_HIT_SSDONE: + /* + * We increment the nmissed count for accounting, + * we can also use npre/npostfault count for accouting + * these specific fault cases. + */ + kprobes_inc_nmissed_count(cur); + + /* + * We come here because instructions in the pre/post + * handler caused the page_fault, this could happen + * if handler tries to access user space by + * copy_from_user(), get_user() etc. Let the + * user-specified handler try to fix it first. + */ + if (cur->fault_handler && cur->fault_handler(cur, regs, trapnr)) + return 1; + + /* + * Let ia64_do_page_fault() fix it. + */ + break; + default: + break; } return 0; |