[PATCH 1/3] riscv: Fixup static_obj() fail

From: guoren
Date: Tue Jun 16 2020 - 11:58:43 EST


From: Guo Ren <guoren@xxxxxxxxxxxxxxxxx>

When enable LOCKDEP, static_obj() will cause error. Because some
__initdata static variables is before _stext:

static int static_obj(const void *obj)
{
unsigned long start = (unsigned long) &_stext,
end = (unsigned long) &_end,
addr = (unsigned long) obj;

/*
* static variable?
*/
if ((addr >= start) && (addr < end))
return 1;

[ 0.067192] INFO: trying to register non-static key.
[ 0.067325] the code is fine but needs lockdep annotation.
[ 0.067449] turning off the locking correctness validator.
[ 0.067718] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.7.0-rc7-dirty #44
[ 0.067945] Call Trace:
[ 0.068369] [<ffffffe00020323c>] walk_stackframe+0x0/0xa4
[ 0.068506] [<ffffffe000203422>] show_stack+0x2a/0x34
[ 0.068631] [<ffffffe000521e4e>] dump_stack+0x94/0xca
[ 0.068757] [<ffffffe000255a4e>] register_lock_class+0x5b8/0x5bc
[ 0.068969] [<ffffffe000255abe>] __lock_acquire+0x6c/0x1d5c
[ 0.069101] [<ffffffe0002550fe>] lock_acquire+0xae/0x312
[ 0.069228] [<ffffffe000989a8e>] _raw_spin_lock_irqsave+0x40/0x5a
[ 0.069357] [<ffffffe000247c64>] complete+0x1e/0x50
[ 0.069479] [<ffffffe000984c38>] rest_init+0x1b0/0x28a
[ 0.069660] [<ffffffe0000016a2>] 0xffffffe0000016a2
[ 0.069779] [<ffffffe000001b84>] 0xffffffe000001b84
[ 0.069953] [<ffffffe000001092>] 0xffffffe000001092

static __initdata DECLARE_COMPLETION(kthreadd_done);

noinline void __ref rest_init(void)
{
...
complete(&kthreadd_done);

Signed-off-by: Guo Ren <guoren@xxxxxxxxxxxxxxxxx>
---
arch/riscv/kernel/vmlinux.lds.S | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/riscv/kernel/vmlinux.lds.S b/arch/riscv/kernel/vmlinux.lds.S
index 0339b6b..bf3f34d 100644
--- a/arch/riscv/kernel/vmlinux.lds.S
+++ b/arch/riscv/kernel/vmlinux.lds.S
@@ -22,6 +22,7 @@ SECTIONS
/* Beginning of code and text segment */
. = LOAD_OFFSET;
_start = .;
+ _stext = .;
HEAD_TEXT_SECTION
. = ALIGN(PAGE_SIZE);

@@ -49,7 +50,6 @@ SECTIONS
. = ALIGN(SECTION_ALIGN);
.text : {
_text = .;
- _stext = .;
TEXT_TEXT
SCHED_TEXT
CPUIDLE_TEXT
--
2.7.4