Re: [PATCH 6/6] fs: replace f_ops->get_poll_head with a static ->f_poll_head pointer

On Thu, Jun 28, 2018 at 1:37 PM Al Viro [off-list ref] wrote:

Speaking of obvious bogosities (a lot more so than a blocking allocation
several calls down into helper):

static __poll_t ca8210_test_int_poll(
        struct file *filp,
        struct poll_table_struct *ptable
)

Ok, that's just garbage.

Again, this is not an excuse for changing "->poll()". This is just a
bogus driver that does stupid things.

And again, don't use this as an example of "poll must not block" The
fact is, poll() *can* block for locking and other such things, and
it's perfectly normal and ok. It just shouldn't block for IO.

I will not take any misguided patches to try to "fix" poll functions
that might block.

But I will take patches to fix bugs in drivers. In this case, I think
the fix is to just remove that crazy "wait_event_interruptible()"
entirely.

Not that anybody cares, obviously. Apparently nobody has ever noticed
how broken that poll function is.

               Linus