From: Zqiang <qiang.zhang@xxxxxxxxxxxxx> 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/20210329084009.27013-1-qiang.zhang@xxxxxxxxxxxxx Signed-off-by: Zqiang <qiang.zhang@xxxxxxxxxxxxx> Reported-by: Andrew Halaney <ahalaney@xxxxxxxxxx> Cc: Alexander Potapenko <glider@xxxxxxxxxx> Cc: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx> Cc: Vijayanand Jitta <vjitta@xxxxxxxxxxxxxx> Cc: Vinayak Menon <vinmenon@xxxxxxxxxxxxxx> Cc: Yogesh Lal <ylal@xxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- lib/stackdepot.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- 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. */ _
