void kmemcheck_show(struct pt_regs *regs)
{
struct kmemcheck_context *data = &__get_cpu_var(kmemcheck_context);
BUG_ON(!irqs_disabled());
if (unlikely(data->balance != 0)) {
kmemcheck_show_all();
kmemcheck_error_save_bug(regs);
data->balance = 0;
return;
}
if (kmemcheck_show_all() == 0)
return;
++data->balance;
if (!(regs->flags & X86_EFLAGS_TF))
data->flags = regs->flags;
regs->flags |= X86_EFLAGS_TF;
regs->flags &= ~X86_EFLAGS_IF;
}
/*
* Called from the #DB handler.
*/
void kmemcheck_hide(struct pt_regs *regs)
{
struct kmemcheck_context *data = &__get_cpu_var(kmemcheck_context);
int n;
BUG_ON(!irqs_disabled());
if (unlikely(data->balance != 1)) {
kmemcheck_show_all();
kmemcheck_error_save_bug(regs);
data->n_addrs = 0;
data->balance = 0;
if (!(data->flags & X86_EFLAGS_TF))
regs->flags &= ~X86_EFLAGS_TF;
if (data->flags & X86_EFLAGS_IF)
regs->flags |= X86_EFLAGS_IF;
return;
}
if (kmemcheck_enabled)
n = kmemcheck_hide_all();
else
n = kmemcheck_show_all();
if (n == 0)
return;
--data->balance;
data->n_addrs = 0;
if (!(data->flags & X86_EFLAGS_TF))
regs->flags &= ~X86_EFLAGS_TF;
if (data->flags & X86_EFLAGS_IF)
regs->flags |= X86_EFLAGS_IF;
}
/*
* Called from the #PF handler.
*/
void kmemcheck_show(struct pt_regs *regs)
{
struct kmemcheck_context *data = &__get_cpu_var(kmemcheck_context);
BUG_ON(!irqs_disabled());
if (unlikely(data->balance != 0)) {
kmemcheck_show_all();
kmemcheck_error_save_bug(regs);
data->balance = 0;
return;
}
/*
* None of the addresses actually belonged to kmemcheck. Note that
* this is not an error.
*/
if (kmemcheck_show_all() == 0)
return;
++data->balance;
/*
* The IF needs to be cleared as well, so that the faulting
* instruction can run "uninterrupted". Otherwise, we might take
* an interrupt and start executing that before we've had a chance
* to hide the page again.
*
* NOTE: In the rare case of multiple faults, we must not override
* the original flags:
*/
if (!(regs->flags & X86_EFLAGS_TF))
data->flags = regs->flags;
regs->flags |= X86_EFLAGS_TF;
regs->flags &= ~X86_EFLAGS_IF;
}