Messages in this thread | | | Date | Thu, 1 Oct 2015 13:51:05 +0200 (CEST) | From | Thomas Gleixner <> | Subject | Re: [PATCH 06/25] x86, pkeys: PTE bits for storing protection key |
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On Mon, 28 Sep 2015, Dave Hansen wrote: > From: Dave Hansen <dave.hansen@linux.intel.com> > > Previous documentation has referred to these 4 bits as "ignored". > That means that software could have made use of them. But, as > far as I know, the kernel never used them. > > They are still ignored when protection keys is not enabled, so > they could theoretically still get used for software purposes. > > We also implement "empty" versions so that code that references > to them can be optimized away by the compiler when the config > option is not enabled. > > Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
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