linux-kernel - RE: [PATCH V2 3/9] clk: imx: Support building SCU clock driver as module

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: Windows password security audit tool. GUI, reports in PDF.

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

Message-ID: <AM6PR04MB496690A045E0BFFF3D03AE0380940@AM6PR04MB4966.eurprd04.prod.outlook.com>
Date:   Tue, 23 Jun 2020 03:42:19 +0000
From:   Aisheng Dong <aisheng.dong@....com>
To:     Stephen Boyd <sboyd@...nel.org>, Abel Vesa <abel.vesa@....com>,
        Andy Duan <fugang.duan@....com>,
        Anson Huang <anson.huang@....com>,
        Daniel Baluta <daniel.baluta@....com>,
        Leonard Crestez <leonard.crestez@....com>,
        Peng Fan <peng.fan@....com>,
        Stefan Agner <stefan.agner@...adex.com>,
        "allison@...utok.net" <allison@...utok.net>,
        "arnd@...db.de" <arnd@...db.de>,
        "festevam@...il.com" <festevam@...il.com>,
        "gregkh@...uxfoundation.org" <gregkh@...uxfoundation.org>,
        "info@...ux.net" <info@...ux.net>,
        "kernel@...gutronix.de" <kernel@...gutronix.de>,
        "linux-arm-kernel@...ts.infradead.org" 
        <linux-arm-kernel@...ts.infradead.org>,
        "linux-clk@...r.kernel.org" <linux-clk@...r.kernel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "linux@...linux.org.uk" <linux@...linux.org.uk>,
        "mturquette@...libre.com" <mturquette@...libre.com>,
        "oleksandr.suvorov@...adex.com" <oleksandr.suvorov@...adex.com>,
        "s.hauer@...gutronix.de" <s.hauer@...gutronix.de>,
        "sfr@...b.auug.org.au" <sfr@...b.auug.org.au>,
        "shawnguo@...nel.org" <shawnguo@...nel.org>,
        "tglx@...utronix.de" <tglx@...utronix.de>,
        "yuehaibing@...wei.com" <yuehaibing@...wei.com>
CC:     dl-linux-imx <linux-imx@....com>
Subject: RE: [PATCH V2 3/9] clk: imx: Support building SCU clock driver as
 module

> From: Stephen Boyd <sboyd@...nel.org>
> Sent: Saturday, June 20, 2020 11:28 AM
> Subject: RE: [PATCH V2 3/9] clk: imx: Support building SCU clock driver as
> module
> 
> Quoting Aisheng Dong (2020-06-17 18:58:51)
> > > From: Anson Huang <anson.huang@....com>
> > > > > +obj-$(CONFIG_MXC_CLK_SCU) += mxc-clk-scu.o
> > > >
> > > > Like i.MX pinctrl, I'm not sure if it's really necessary to build
> > > > core libraries as modules. Probably the simplest way is only
> > > > building platform drivers part as module. And leave those core libraries
> built in kernel.
> > > > This may make the code a bit cleaner.
> > > >
> > >
> > > Will discuss this with Linaro guys about it, previous requirement I
> > > received is all SoC specific modules need to be built as module.
> > >
> >
> > Okay. AFAIK it's not conflict.
> > You still make drivers into modules.
> > Only difference is for those common libraries part, we don't convert
> > them into module Which is less meaningless.
> >
> 
> What is the benefit of making the core part of the SoC driver not a module?

Usually we could try to build it as module if it's not hard.

One question is sometimes those core part are shared with some platforms which can't built as module.
For i.MX case, it's mainly patch 4:
[V2,4/9] clk: imx: Support building i.MX common clock driver as module
https://patchwork.kernel.org/patch/11594801/

Those libraries are also used by i.MX6&7 which can't build as module.
So we need an extra workaround patch to forcely 'select' it under arch/arm/mach-imx/Kconfig
[V2,2/9] ARM: imx: Select MXC_CLK for ARCH_MXC
https://patchwork.kernel.org/patch/11594793/
Then the users can't configure it as module in order to not break build.

If build-in those common libraries, the implementation could be a bit easier and cleaner.
So I'm not sure if we still have to build them as module.
How would you suggest for such case?

> From the module perspective it should be perfectly fine to make it a module as
> well, and then depmod will sort out loading modules in the right order.
> 
> This is for android right?

Yes, for Android GKI support.

Regards
Aisheng