linux-kernel - Re: [PATCH] mfd: db8500-prcmu: fix irqdomain usage

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Thu, 20 Dec 2012 10:17:17 +0100
From:	Linus Walleij <linus.walleij@...aro.org>
To:	Lee Jones <lee.jones@...aro.org>
Cc:	Grant Likely <grant.likely@...retlab.ca>,
	Linus Walleij <linus.walleij@...ricsson.com>,
	Samuel Ortiz <sameo@...ux.intel.com>,
	linux-kernel@...r.kernel.org, Anmar Oueja <anmar.oueja@...aro.org>,
	stable@...nel.org
Subject: Re: [PATCH] mfd: db8500-prcmu: fix irqdomain usage

On Thu, Dec 20, 2012 at 8:50 AM, Lee Jones <lee.jones@...aro.org> wrote:
> On Thu, 20 Dec 2012, Grant Likely wrote:
>>
>> This looks wrong. It probably works at the moment, but calling
>> irq_create_mapping when trying to process an IRQ is backwards. There
>> certainly shouldn't be any processing of an irq that isn't already
>> mapped. irq_find_mapping() should be used instead.
>
> But irq_create_mapping() calls irq_find_mapping() if the irq is
> already mapped? Or are you saying that if it isn't already mapped
> then there is an issue somewhere else earlier in the code?

I've submitted a v2 patch making the changes I think Grant is
fishing for..

Basically irq_create_mapping() should be in slowpath and
irq_find_mapping() in fastpath with the semantics that
the former has to be called at least once before the other
is ever called.

This is not quite trivial to use ... irqdomain seems like it
will bite us repeatedly for the next few years.

Yours,
Linus Walleij
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/