Re: [PATCH v4 06/19] irqdomain: Drop revmap mutex
From: Johan Hovold <johan@kernel.org>
Date: 2023-01-18 10:15:43
Also in:
linux-mips, lkml, platform-driver-x86
On Tue, Jan 17, 2023 at 10:23:20PM +0100, Thomas Gleixner wrote:
On Mon, Jan 16 2023 at 14:50, Johan Hovold wrote:quoted
The global irq_domain_mutex is now held in all paths that update the revmap structures so there is no longer any need for the revmap mutex.This can also go after the 3rd race fix, but ...quoted
static void irq_domain_clear_mapping(struct irq_domain *domain, irq_hw_number_t hwirq) { + lockdep_assert_held(&irq_domain_mutex);these lockdep asserts want to be part of the [dis]association race fixes. They are completely unrelated to the removal of the revmap_mutex.
No, they are very much related to the removal of the revmap_mutex. These functions deal with the revmap structures which before this patch were clearly only modified with the revmap_mutex held. The lockdep assert is here to guarantee that my claim that all current (and future) paths that end up modifying these structures do so under the irq_domain_mutex instead.
Your race fixes change the locking and you want to ensure that all callers comply right there, no?
I want to make sure that all callers of these function comply, yes. That's why the asserts belong in this patch. Johan _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel