[PATCH 2/3] x86/unwind: Show function name+offset in ORC error messages

Josh Poimboeuf
2017-10-20T16:22:03Z

Improve the warning messages to show the relevant function name+offset.
This makes it much easier to diagnose problems with the ORC metadata.

Before:

WARNING: can't dereference iret registers at ffff8801c5f17fe0 for ip ffffffff95f0d94b

After:

WARNING: can't dereference iret registers at ffff880178f5ffe0 for ip int3+0x5b/0x60

Reported-by: Andrei Vagin <avagin@virtuozzo.com>
Fixes: ee9f8fce9964 ("x86/unwind: Add the ORC unwinder")
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
---
arch/x86/kernel/unwind_orc.c | 29 +++++++++++++++--------------
1 file changed, 15 insertions(+), 14 deletions(-)

diff --git a/arch/x86/kernel/unwind_orc.c b/arch/x86/kernel/unwind_orc.c
index 570b70d3f604..b95007e7c1b3 100644
--- a/arch/x86/kernel/unwind_orc.c
+++ b/arch/x86/kernel/unwind_orc.c
@@ -86,8 +86,8 @@ static struct orc_entry *orc_find(unsigned long ip)
idx = (ip - LOOKUP_START_IP) / LOOKUP_BLOCK_SIZE;

if (unlikely((idx >= lookup_num_blocks-1))) {
- orc_warn("WARNING: bad lookup idx: idx=%u num=%u ip=%lx\n",
- idx, lookup_num_blocks, ip);
+ orc_warn("WARNING: bad lookup idx: idx=%u num=%u ip=%pB\n",
+ idx, lookup_num_blocks, (void *)ip);
return NULL;
}

@@ -96,8 +96,8 @@ static struct orc_entry *orc_find(unsigned long ip)

if (unlikely((__start_orc_unwind + start >= __stop_orc_unwind) ||
(__start_orc_unwind + stop > __stop_orc_unwind))) {
- orc_warn("WARNING: bad lookup value: idx=%u num=%u start=%u stop=%u ip=%lx\n",
- idx, lookup_num_blocks, start, stop, ip);
+ orc_warn("WARNING: bad lookup value: idx=%u num=%u start=%u stop=%u ip=%pB\n",
+ idx, lookup_num_blocks, start, stop, (void *)ip);
return NULL;
}

@@ -373,7 +373,7 @@ bool unwind_next_frame(struct unwind_state *state)

case ORC_REG_R10:
if (!state->regs || !state->full_regs) {
- orc_warn("missing regs for base reg R10 at ip %p\n",
+ orc_warn("missing regs for base reg R10 at ip %pB\n",
(void *)state->ip);
goto done;
}
@@ -382,7 +382,7 @@ bool unwind_next_frame(struct unwind_state *state)

case ORC_REG_R13:
if (!state->regs || !state->full_regs) {
- orc_warn("missing regs for base reg R13 at ip %p\n",
+ orc_warn("missing regs for base reg R13 at ip %pB\n",
(void *)state->ip);
goto done;
}
@@ -391,7 +391,7 @@ bool unwind_next_frame(struct unwind_state *state)

case ORC_REG_DI:
if (!state->regs || !state->full_regs) {
- orc_warn("missing regs for base reg DI at ip %p\n",
+ orc_warn("missing regs for base reg DI at ip %pB\n",
(void *)state->ip);
goto done;
}
@@ -400,7 +400,7 @@ bool unwind_next_frame(struct unwind_state *state)

case ORC_REG_DX:
if (!state->regs || !state->full_regs) {
- orc_warn("missing regs for base reg DX at ip %p\n",
+ orc_warn("missing regs for base reg DX at ip %pB\n",
(void *)state->ip);
goto done;
}
@@ -408,7 +408,7 @@ bool unwind_next_frame(struct unwind_state *state)
break;

default:
- orc_warn("unknown SP base reg %d for ip %p\n",
+ orc_warn("unknown SP base reg %d for ip %pB\n",
orc->sp_reg, (void *)state->ip);
goto done;
}
@@ -436,7 +436,7 @@ bool unwind_next_frame(struct unwind_state *state)

case ORC_TYPE_REGS:
if (!deref_stack_regs(state, sp, &state->ip, &state->sp, true)) {
- orc_warn("can't dereference registers at %p for ip %p\n",
+ orc_warn("can't dereference registers at %p for ip %pB\n",
(void *)sp, (void *)orig_ip);
goto done;
}
@@ -448,7 +448,7 @@ bool unwind_next_frame(struct unwind_state *state)

case ORC_TYPE_REGS_IRET:
if (!deref_stack_regs(state, sp, &state->ip, &state->sp, false)) {
- orc_warn("can't dereference iret registers at %p for ip %p\n",
+ orc_warn("can't dereference iret registers at %p for ip %pB\n",
(void *)sp, (void *)orig_ip);
goto done;
}
@@ -465,7 +465,8 @@ bool unwind_next_frame(struct unwind_state *state)
break;

default:
- orc_warn("unknown .orc_unwind entry type %d\n", orc->type);
+ orc_warn("unknown .orc_unwind entry type %d for ip %pB\n",
+ orc->type, (void *)orig_ip);
break;
}

@@ -487,7 +488,7 @@ bool unwind_next_frame(struct unwind_state *state)
break;

default:
- orc_warn("unknown BP base reg %d for ip %p\n",
+ orc_warn("unknown BP base reg %d for ip %pB\n",
orc->bp_reg, (void *)orig_ip);
goto done;
}
@@ -496,7 +497,7 @@ bool unwind_next_frame(struct unwind_state *state)
if (state->stack_info.type == prev_type &&
on_stack(&state->stack_info, (void *)state->sp, sizeof(long)) &&
state->sp <= prev_sp) {
- orc_warn("stack going in the wrong direction? ip=%p\n",
+ orc_warn("stack going in the wrong direction? ip=%pB\n",
(void *)orig_ip);
goto done;
}
--
2.13.6