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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Wed, 14 Feb 2024 11:03:46 -0800
Message-ID: <CAHk-=wiVWmTfaCUjZYrV6pVh3O6hYksKsWx4bJY0EhNNat9QDg@mail.gmail.com>
Subject: Re: [PATCH wq/for-6.9] workqueue: Fix queue_work_on() with BH workqueues
To: Tejun Heo <tj@kernel.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>, linux-kernel@vger.kernel.org
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On Wed, 14 Feb 2024 at 10:39, Tejun Heo <tj@kernel.org> wrote:
>
> When queue_work_on() is used to queue a BH work item on a remote CPU, the
> work item is queued on that CPU but kick_pool() raises softirq on the local
> CPU.

Now, does it make a lot of sense to ask to queue a BH work on another
CPU in the first place?

I don't think tasklets supported that. And while the workqueues
obviously do - and you fix that case - I wonder if we shouldn't say
"that operation makes no sense, please don't do it" rather than
actually support it?

What made you notice this issue?

                  Linus