[PATCH v2] LoongArch: Remove some checks for ORC unwinder

From: Tiezhu Yang

Date: Mon Dec 15 2025 - 20:53:51 EST


According to the following function definitions, __kernel_text_address()
already checks __module_text_address(), so it should remove the check of
__module_text_address() in bt_address() at least.

int __kernel_text_address(unsigned long addr)
{
if (kernel_text_address(addr))
return 1;
...
return 0;
}

int kernel_text_address(unsigned long addr)
{
bool no_rcu;
int ret = 1;
...
if (is_module_text_address(addr))
goto out;
...
return ret;
}

bool is_module_text_address(unsigned long addr)
{
guard(rcu)();
return __module_text_address(addr) != NULL;
}

Furthermore, there are two checks of __kernel_text_address(), one is in
bt_address() and the other is after calling bt_address(), it looks like
redundant.

Handle the exception address first and then use __kernel_text_address()
to validate the calculated address for exception or the normal address
in bt_address(), then it can remove the check of __kernel_text_address()
after calling bt_address().

Just remove unnecessary checks, no functional changes intended.

Signed-off-by: Tiezhu Yang <yangtiezhu@xxxxxxxxxxx>
---
arch/loongarch/kernel/unwind_orc.c | 16 +++++-----------
1 file changed, 5 insertions(+), 11 deletions(-)

diff --git a/arch/loongarch/kernel/unwind_orc.c b/arch/loongarch/kernel/unwind_orc.c
index 0d5fa64a2225..fe4fe5f266b9 100644
--- a/arch/loongarch/kernel/unwind_orc.c
+++ b/arch/loongarch/kernel/unwind_orc.c
@@ -360,12 +360,6 @@ static inline unsigned long bt_address(unsigned long ra)
{
extern unsigned long eentry;

- if (__kernel_text_address(ra))
- return ra;
-
- if (__module_text_address(ra))
- return ra;
-
if (ra >= eentry && ra < eentry + EXCCODE_INT_END * VECSIZE) {
unsigned long func;
unsigned long type = (ra - eentry) / VECSIZE;
@@ -383,10 +377,13 @@ static inline unsigned long bt_address(unsigned long ra)
break;
}

- return func + offset;
+ ra = func + offset;
}

- return ra;
+ if (__kernel_text_address(ra))
+ return ra;
+
+ return 0;
}

bool unwind_next_frame(struct unwind_state *state)
@@ -512,9 +509,6 @@ bool unwind_next_frame(struct unwind_state *state)
goto err;
}

- if (!__kernel_text_address(state->pc))
- goto err;
-
return true;

err:
--
2.42.0