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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Wed, 1 Nov 2017 12:05:44 -0700
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Subject: Re: [PATCH 00/23] KAISER: unmap most of the kernel from userspace
 page tables
To: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        linux-mm <linux-mm@kvack.org>, Kees Cook <keescook@google.com>,
        Hugh Dickins <hughd@google.com>
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On Wed, Nov 1, 2017 at 11:46 AM, Dave Hansen
<dave.hansen@linux.intel.com> wrote:
>
> The vmalloc()'d stacks definitely need the page table walk.

Ugh, yes. Nasty.

Andy at some point mentioned a per-cpu initial stack trampoline thing
for his exception patches, but I'm not sure he actually ever did that.

Andy?

              Linus