diff options
Diffstat (limited to 'kernel/bpf/stackmap.c')
| -rw-r--r-- | kernel/bpf/stackmap.c | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c index 4d31284095e2..3f958b90d914 100644 --- a/kernel/bpf/stackmap.c +++ b/kernel/bpf/stackmap.c @@ -287,7 +287,7 @@ static void stack_map_get_build_id_offset(struct bpf_stack_build_id *id_offs, bool irq_work_busy = false; struct stack_map_irq_work *work = NULL; - if (in_nmi()) { + if (irqs_disabled()) { work = this_cpu_ptr(&up_read_work); if (atomic_read(&work->irq_work.flags) & IRQ_WORK_BUSY) /* cannot queue more up_read, fallback */ @@ -295,8 +295,9 @@ static void stack_map_get_build_id_offset(struct bpf_stack_build_id *id_offs, } /* - * We cannot do up_read() in nmi context. To do build_id lookup - * in nmi context, we need to run up_read() in irq_work. We use + * We cannot do up_read() when the irq is disabled, because of + * risk to deadlock with rq_lock. To do build_id lookup when the + * irqs are disabled, we need to run up_read() in irq_work. We use * a percpu variable to do the irq_work. If the irq_work is * already used by another lookup, we fall back to report ips. * @@ -338,7 +339,7 @@ static void stack_map_get_build_id_offset(struct bpf_stack_build_id *id_offs, * up_read_non_owner(). The rwsem_release() is called * here to release the lock from lockdep's perspective. */ - rwsem_release(¤t->mm->mmap_sem.dep_map, 1, _RET_IP_); + rwsem_release(¤t->mm->mmap_sem.dep_map, _RET_IP_); } } |