return true;
}
+/*
+ * If state->regs is non-NULL, and points to a full pt_regs, just get the reg
+ * value from state->regs.
+ *
+ * Otherwise, if state->regs just points to IRET regs, and the previous frame
+ * had full regs, it's safe to get the value from the previous regs. This can
+ * happen when early/late IRQ entry code gets interrupted by an NMI.
+ */
+static bool get_reg(struct unwind_state *state, unsigned int reg_off,
+ unsigned long *val)
+{
+ unsigned int reg = reg_off/8;
+
+ if (!state->regs)
+ return false;
+
+ if (state->full_regs) {
+ *val = ((unsigned long *)state->regs)[reg];
+ return true;
+ }
+
+ if (state->prev_regs) {
+ *val = ((unsigned long *)state->prev_regs)[reg];
+ return true;
+ }
+
+ return false;
+}
+
bool unwind_next_frame(struct unwind_state *state)
{
- unsigned long ip_p, sp, orig_ip = state->ip, prev_sp = state->sp;
+ unsigned long ip_p, sp, tmp, orig_ip = state->ip, prev_sp = state->sp;
enum stack_type prev_type = state->stack_info.type;
struct orc_entry *orc;
bool indirect = false;
break;
case ORC_REG_R10:
- if (!state->regs || !state->full_regs) {
+ if (!get_reg(state, offsetof(struct pt_regs, r10), &sp)) {
orc_warn_current("missing R10 value at %pB\n",
(void *)state->ip);
goto err;
}
- sp = state->regs->r10;
break;
case ORC_REG_R13:
- if (!state->regs || !state->full_regs) {
+ if (!get_reg(state, offsetof(struct pt_regs, r13), &sp)) {
orc_warn_current("missing R13 value at %pB\n",
(void *)state->ip);
goto err;
}
- sp = state->regs->r13;
break;
case ORC_REG_DI:
- if (!state->regs || !state->full_regs) {
+ if (!get_reg(state, offsetof(struct pt_regs, di), &sp)) {
orc_warn_current("missing RDI value at %pB\n",
(void *)state->ip);
goto err;
}
- sp = state->regs->di;
break;
case ORC_REG_DX:
- if (!state->regs || !state->full_regs) {
+ if (!get_reg(state, offsetof(struct pt_regs, dx), &sp)) {
orc_warn_current("missing DX value at %pB\n",
(void *)state->ip);
goto err;
}
- sp = state->regs->dx;
break;
default:
state->sp = sp;
state->regs = NULL;
+ state->prev_regs = NULL;
state->signal = false;
break;
}
state->regs = (struct pt_regs *)sp;
+ state->prev_regs = NULL;
state->full_regs = true;
state->signal = true;
break;
goto err;
}
+ if (state->full_regs)
+ state->prev_regs = state->regs;
state->regs = (void *)sp - IRET_FRAME_OFFSET;
state->full_regs = false;
state->signal = true;
/* Find BP: */
switch (orc->bp_reg) {
case ORC_REG_UNDEFINED:
- if (state->regs && state->full_regs)
- state->bp = state->regs->bp;
+ if (get_reg(state, offsetof(struct pt_regs, bp), &tmp))
+ state->bp = tmp;
break;
case ORC_REG_PREV_SP: