From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Subject: Re: [PATCH v11 09/13] x86, sgx: basic routines for enclave page
 cache
Date: Mon, 25 Jun 2018 12:01:12 +0300
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To: Dave Hansen <dave.hansen@intel.com>
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On Tue, 2018-06-19 at 08:32 -0700, Dave Hansen wrote:
> > For 32-bit (albeit not supported at this point) it makes sense to always
> > use kmap_atomic_pfn() as the virtua address area is very limited.
> 
> That makes no sense.  32-bit kernels have plenty of virtual address
> space if not using highmem.

AFAIK the vmalloc area is located in the last 128MB that and ioremap()
of EPC would consume a big portion of that.

> > KVM works only with writable MSRs. Driver works both with writable
> > and read-only MSRs.
> 
> Could you help with my confusion by documenting this a bit?

Sure.

/Jarkko