[31/91] lib: stackdepot: turn depot_lock spinlock to raw_spinlock

Commit Message

Andrew Morton May 7, 2021, 1:03 a.m. UTC

From: Zqiang <[e-mail]>
Subject: lib: stackdepot: turn depot_lock spinlock to raw_spinlock

[    2.670635] BUG: sleeping function called from invalid context
at kernel/locking/rtmutex.c:951
[    2.670638] in_atomic(): 0, irqs_disabled(): 1, non_block: 0,
pid: 19, name: pgdatinit0
[    2.670768] Call Trace:
[    2.670800]  dump_stack+0x93/0xc2
[    2.670826]  ___might_sleep.cold+0x1b2/0x1f1
[    2.670838]  rt_spin_lock+0x3b/0xb0
[    2.670838]  stack_depot_save+0x1b9/0x440
[    2.670838]  kasan_save_stack+0x32/0x40
[    2.670838]  kasan_record_aux_stack+0xa5/0xb0
[    2.670838]  __call_rcu+0x117/0x880
[    2.670838]  __exit_signal+0xafb/0x1180
[    2.670838]  release_task+0x1d6/0x480
[    2.670838]  exit_notify+0x303/0x750
[    2.670838]  do_exit+0x678/0xcf0
[    2.670838]  kthread+0x364/0x4f0
[    2.670838]  ret_from_fork+0x22/0x30

In RT system, the spin_lock will be replaced by sleepable rt_mutex lock,
in __call_rcu(), disable interrupts before calling
kasan_record_aux_stack(), will trigger above calltrace, replace spinlock
with raw_spinlock.

Link: https://lkml.kernel.org/r/[e-mail]
Signed-off-by: Zqiang <[e-mail]>
Reported-by: Andrew Halaney <[e-mail]>
Cc: Alexander Potapenko <[e-mail]>
Cc: Gustavo A. R. Silva <[e-mail]>
Cc: Vijayanand Jitta <[e-mail]>
Cc: Vinayak Menon <[e-mail]>
Cc: Yogesh Lal <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
---

 lib/stackdepot.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

Patch

--- a/lib/stackdepot.c~lib-stackdepot-turn-depot_lock-spinlock-to-raw_spinlock
+++ a/lib/stackdepot.c
@@ -71,7 +71,7 @@  static void *stack_slabs[STACK_ALLOC_MAX
 static int depot_index;
 static int next_slab_inited;
 static size_t depot_offset;
-static DEFINE_SPINLOCK(depot_lock);
+static DEFINE_RAW_SPINLOCK(depot_lock);
 
 static bool init_stack_slab(void **prealloc)
 {
@@ -305,7 +305,7 @@  depot_stack_handle_t stack_depot_save(un
 			prealloc = page_address(page);
 	}
 
-	spin_lock_irqsave(&depot_lock, flags);
+	raw_spin_lock_irqsave(&depot_lock, flags);
 
 	found = find_stack(*bucket, entries, nr_entries, hash);
 	if (!found) {
@@ -329,7 +329,7 @@  depot_stack_handle_t stack_depot_save(un
 		WARN_ON(!init_stack_slab(&prealloc));
 	}
 
-	spin_unlock_irqrestore(&depot_lock, flags);
+	raw_spin_unlock_irqrestore(&depot_lock, flags);
 exit:
 	if (prealloc) {
 		/* Nobody used this memory, ok to free it. */