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Date: Sun, 7 Jan 2018 22:39:45 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cc: LKML <linux-kernel@vger.kernel.org>,
        Linus Torvalds <torvalds@linuxfoundation.org>,
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        Borislav Petkov <bp@alien8.de>,
        David Woodhouse <dwmw@amazon.co.uk>,
        "Hansen, Dave" <dave.hansen@intel.com>
Subject: Re: [patch 1/2] sysfs/cpu: Add vulnerability folder
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On Sun, 7 Jan 2018, Greg Kroah-Hartman wrote:
> >  drivers/base/Kconfig |    3 +++
> >  drivers/base/cpu.c   |   48 ++++++++++++++++++++++++++++++++++++++++++++++++
> >  include/linux/cpu.h  |    7 +++++++
> >  3 files changed, 58 insertions(+)
> 
> A Documentation/ABI/ update is needed for the new sysfs files.

Sure.

> > +#ifdef CONFIG_GENERIC_CPU_VULNERABILITIES
> > +
> > +ssize_t __weak cpu_show_meltdown(struct device *dev,
> > +				 struct device_attribute *attr, char *buf)
> > +{
> > +	return snprintf(buf, PAGE_SIZE - 2, "Not affected\n");
> 
> sysfs is one-value-per-file, so you never need to care about the page
> size, a simple sprintf() is fine.  No need to change if you don't want
> to, your call.

Done.

> > +static DEVICE_ATTR(spectre_v2, 0444, cpu_show_spectre_v2, NULL);
> 
> DEVICE_ATTR_RO() please.
> 
> Yeah, that does make the global symbols a bit different, meltdown_show()
> and the like.  Hm, I guess this is ok, given that it's ment to be
> overridden.

That and I expect that in the not so distant future we'll see write
functions as well.

> Oh, nevermind.  So, just a documentation update please, that can always
> be an add-on patch if you promise to do it :)

You should never make such offers. These promises land on that growth only
thingy, aka. todo list :)

Thanks,

	tglx