Re: [PATCH] genirq/debugfs: add new config option for trigger interrupt from userspace

From: Marc Zyngier
Date: Fri Feb 28 2020 - 14:54:08 EST


On 2020-02-28 19:13, Joe Jin wrote:
Hi Marc,

Thanks for your reply.

On 2/28/20 8:37 AM, Marc Zyngier wrote:
On 2020-02-28 05:42, Joe Jin wrote:
commit 536e2e34bd00 ("genirq/debugfs: Triggering of interrupts from
userspace") is allowed developer inject interrupts via irq debugfs, which
is very useful during development phase, but on a production system, this
is very dangerous, add new config option, developers can enable it as
needed instead of enabling it by default when irq debugfs is enabled.

I don't really mind the patch (although it could be more elegant), but in
general I object to most debugfs options being set on a production kernel.
There is way too much information in most debugfs backends to be comfortable
with it, and you can find things like page table dumps, for example...

We should not enable any debug option on production system, actual customer
want to resize their BM or VM, cpu offline may lead system not works properly,
and if we knew more details of IRQ info it will be very help to identify
if it caused by IRQ/vectors, this is the motivation of we want to enable it
on production kernel.

If something doesn't work properly, then you are still debugging, AFAICT.

M.
--
Jazz is not dead. It just smells funny...