Re: [PATCH v4] pipe: use __pipe_{lock,unlock} instead of spinlock

Linus Torvalds
2023-02-06T18:25:28Z

On Mon, Feb 6, 2023 at 8:45 AM Dan Carpenter <error27@gmail.com> wrote:
>
> You need the cross function database to review these warnings. [...]
>
> hl_device_set_debug_mode() take a mutex. Then you do
> `smdb.py preempt hl_ctx_fini` and it prints out the call tree which
> disables preemption.
>
> cs_ioctl_unreserve_signals() <- disables preempt
> -> hl_ctx_put()
> -> hl_ctx_do_release()
> -> hl_ctx_fini()
>
> And so on.

Hmm. Do you have automation to do that at least for the non-driver (ie
"core kernel code") ones?

They are *hopefully* false positives, but if not they are obviously
the most interesting.

And they are presumably not quite as overwhelming as all the driver
ones, so even if they *are* false positives, maybe they would then be
the point to start looking at why the tool gives the wrong answer?

Linus