On Mon, Sep 25, 2017 at 05:31:05PM +0000, Mario.Limonciello@xxxxxxxx wrote: > > -----Original Message----- > > From: Andy Shevchenko [mailto:andy.shevchenko@xxxxxxxxx] > > Sent: Monday, September 25, 2017 1:04 PM > > To: Pali Rohár <pali.rohar@xxxxxxxxx> > > Cc: Limonciello, Mario <Mario_Limonciello@xxxxxxxx>; dvhart@xxxxxxxxxxxxx; > > LKML <linux-kernel@xxxxxxxxxxxxxxx>; Platform Driver <platform-driver- > > x86@xxxxxxxxxxxxxxx>; quasisec@xxxxxxxxxx > > Subject: Re: [PATCH 06/12] platform/x86: dell-wmi-smbios: Add a sysfs interface > > for SMBIOS tokens > > > > On Mon, Sep 25, 2017 at 7:23 PM, Pali Rohár <pali.rohar@xxxxxxxxx> wrote: > > > On Thursday 21 September 2017 08:57:11 Mario Limonciello wrote: > > >> Currently userspace tools can access system tokens via the dcdbas > > >> kernel module and a SMI call that will cause the platform to execute > > >> SMM code. > > >> > > >> With a goal in mind of deprecating the dcdbas kernel module a different > > >> method for accessing these tokens from userspace needs to be created. > > >> > > >> This is intentionally marked to only be readable as root as it can > > >> contain sensitive information about the platform's configuration. > > > > > > Darren, Andy, any comments? I'm not quite sure if such API is suitable > > > for long term in kernel. > > > > I would try to avoid sysfs interfaces for some particular devices. > > Besides we are creating a character device. Would it be suitable there? > > If the character device having 2 different ioctls for different needs is > acceptable I'm happy to adjust the series to do this instead. One piece of feedback I had re the char device was to see if we could avoid the need for the IOCTL altogether, I'd like to have that discussion before we add another. > > > > > > Basically tokens are list of tuples <id, location, value> with > > > possibility to active them, right? > > > > > I didn't add a way to activate them through this, it was only for > reading purpose. Activating them should be possible through the > SMBIOS calling interface though. > These are read-only as I understood it, and only with the right privileges. Sysfs seemed appropriate for this to me. -- Darren Hart VMware Open Source Technology Center
