我有一个字符设备驱动程序，它导致多核系统上的系统死锁。写调用有一个由自旋锁 (spin_lock_irqsave) 保护的临界区。ISR 也必须获得此锁才能完成其任务。如果在一个内核上调用 ISR，而写入正在另一个内核上执行临界区，则会由于看门狗定时器检测到 ISR 内核上的硬锁定而发生恐慌。写入过程永远不会返回完成执行。写进程不应该继续在它的核心上执行，释放锁以允许其 ISR 中的另一个核心运行吗？
关键部分大约需要 5us 才能完成。5 秒后发生硬锁定。
我假设我做错了什么，但不知道是什么。
感谢任何帮助！
Turns out the critical section was calling wait_for_completion_timeout. Even though the timeout was zero, it still slept and didn't wake up to release the spin lock if the interrupt occurred in the blocking section. Using try_wait_for_completion in this case resolved the issue.
I would have posted source but it spans many modules and has architecture abstractions for portability between operating systems. Would have been a mess.