linux-kernel - Re: [PATCH 4.19 070/422] pinctrl: ingenic: Probe driver at subsys

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] [day] [month] [year] [list]

Date:   Fri, 22 Nov 2019 19:25:02 +0100
From:   Paul Cercueil <paul@...pouillou.net>
To:     Pavel Machek <pavel@...x.de>
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        linux-kernel@...r.kernel.org, stable@...r.kernel.org,
        Linus Walleij <linus.walleij@...aro.org>,
        Sasha Levin <sashal@...nel.org>
Subject: Re: [PATCH 4.19 070/422] pinctrl: ingenic: Probe driver at
 subsys_initcall

Hi Pavel,

Le jeu., nov. 21, 2019 at 11:17, Pavel Machek <pavel@...x.de> a écrit :
> On Tue 2019-11-19 06:14:27, Greg Kroah-Hartman wrote:
>>  From: Paul Cercueil <paul@...pouillou.net>
>> 
>>  [ Upstream commit 556a36a71ed80e17ade49225b58513ea3c9e4558 ]
>> 
>>  Using postcore_initcall() makes the driver try to initialize way too
>>  early.
> 
> Does it fix concrete bug / would you say it is suitable for -stable?

When using postcore_initcall() it locks up early in the boot process, 
so it definitely fixes a bug. I think it locks up because standard 
(non-early) platform drivers can't be probed postcore (but they can be 
registered and probed later).

> 
>>  +++ b/drivers/pinctrl/pinctrl-ingenic.c
>>  @@ -847,4 +847,4 @@ static int __init 
>> ingenic_pinctrl_drv_register(void)
>>   {
>>   	return platform_driver_register(&ingenic_pinctrl_driver);
>>   }
>>  -postcore_initcall(ingenic_pinctrl_drv_register);
>>  +subsys_initcall(ingenic_pinctrl_drv_register);
> 
> There are other pinctrl drivers initialized very early, do they need
> fixing, too?

The other drivers call platform_driver_register(), not 
platform_driver_probe(), which means that they will probe at the same 
time as the other platform drivers.

The reason platform_driver_probe() is used in pinctrl-ingenic is that 
it allows the probe function and all the code attached to be marked 
__init.

Cheers,
-Paul