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From: Mike Rapoport <rppt@kernel.org>
To: Christopher Lameter <cl@linux.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>,
	linux-kernel@vger.kernel.org,
	Alexey Dobriyan <adobriyan@gmail.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Andy Lutomirski <luto@kernel.org>, Arnd Bergmann <arnd@arndb.de>,
	Borislav Petkov <bp@alien8.de>,
	Dave Hansen <dave.hansen@linux.intel.com>,
	James Bottomley <jejb@linux.ibm.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Steven Rostedt <rostedt@goodmis.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, "H. Peter Anvin" <hpa@zytor.com>,
	linux-api@vger.kernel.org, linux-mm@kvack.org, x86@kernel.org,
	Mike Rapoport <rppt@linux.ibm.com>
Subject: Re: [PATCH RFC] mm: add MAP_EXCLUSIVE to create exclusive user mappings
Date: Wed, 30 Oct 2019 08:11:37 +0100	[thread overview]
Message-ID: <20191030071136.GA20624@rapoport-lnx> (raw)
In-Reply-To: <alpine.DEB.2.21.1910291011090.5411@www.lameter.com>

On Tue, Oct 29, 2019 at 10:12:04AM +0000, Christopher Lameter wrote:
> 
> 
> On Tue, 29 Oct 2019, Mike Rapoport wrote:
> 
> > I've talked with Thomas yesterday and he suggested something similar:
> >
> > When the MAP_EXCLUSIVE request comes for the first time, we allocate a huge
> > page for it and then use this page as a pool of 4K pages for subsequent
> > requests. Once this huge page is full we allocate a new one and append it
> > to the pool. When all the 4K pages that comprise the huge page are freed
> > the huge page is collapsed.
> 
> Or write a device driver that allows you to mmap a secure area and avoid
> all core kernel modifications?
> 
> /dev/securemem or so?

A device driver will need to remove the secure area from the direct map and
then we back to square one.
 
> It may exist already.
> 

-- 
Sincerely yours,
Mike.


  reply	other threads:[~2019-10-30  7:11 UTC|newest]

Thread overview: 60+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-10-27 10:17 [PATCH RFC] mm: add MAP_EXCLUSIVE to create exclusive user mappings Mike Rapoport
2019-10-27 10:17 ` Mike Rapoport
2019-10-28 12:31   ` Kirill A. Shutemov
2019-10-28 13:00     ` Mike Rapoport
2019-10-28 13:16       ` Kirill A. Shutemov
2019-10-28 13:55         ` Peter Zijlstra
2019-10-28 19:59           ` Edgecombe, Rick P
2019-10-28 21:00             ` Peter Zijlstra
2019-10-29 17:27               ` Edgecombe, Rick P
2019-10-30 10:04                 ` Peter Zijlstra
2019-10-30 15:35                   ` Alexei Starovoitov
2019-10-30 18:39                     ` Peter Zijlstra
2019-10-30 18:52                       ` Alexei Starovoitov
2019-10-30 17:48                   ` Edgecombe, Rick P
2019-10-30 17:58                     ` Dave Hansen
2019-10-30 18:01                       ` Dave Hansen
2019-10-29  5:43         ` Dan Williams
2019-10-29  6:43           ` Kirill A. Shutemov
2019-10-29  8:56             ` Peter Zijlstra
2019-10-29 11:00               ` Kirill A. Shutemov
2019-10-29 12:39                 ` AMD TLB errata, (Was: [PATCH RFC] mm: add MAP_EXCLUSIVE to create exclusive user mappings) Peter Zijlstra
2019-11-15 14:12                   ` Tom Lendacky
2019-11-15 14:31                     ` Peter Zijlstra
2019-10-29 19:43             ` [PATCH RFC] mm: add MAP_EXCLUSIVE to create exclusive user mappings Dan Williams
2019-10-29 20:07               ` Dave Hansen
2019-10-29  7:08         ` Christopher Lameter
2019-10-29  8:55           ` Mike Rapoport
2019-10-29 10:12             ` Christopher Lameter
2019-10-30  7:11               ` Mike Rapoport [this message]
2019-10-30 12:09                 ` Christopher Lameter
2019-10-28 14:55   ` David Hildenbrand
2019-10-28 17:12   ` Dave Hansen
2019-10-28 17:32     ` Sean Christopherson
2019-10-28 18:08     ` Matthew Wilcox
2019-10-29  9:28       ` Mike Rapoport
2019-10-29  9:19     ` Mike Rapoport
2019-10-28 18:02   ` Andy Lutomirski
2019-10-29 11:02   ` David Hildenbrand
2019-10-30  8:15     ` Mike Rapoport
2019-10-30  8:19       ` David Hildenbrand
2019-10-31 19:16         ` Mike Rapoport
2019-10-31 21:52           ` Dan Williams
2019-10-27 10:30 ` Florian Weimer
2019-10-27 11:00   ` Mike Rapoport
2019-10-28 20:23     ` Florian Weimer
2019-10-29  9:01       ` Mike Rapoport
2019-10-28 20:44 ` Andy Lutomirski
2019-10-29  9:32   ` Mike Rapoport
2019-10-29 17:00     ` Andy Lutomirski
2019-10-30  8:40       ` Mike Rapoport
2019-10-30 21:28         ` Andy Lutomirski
2019-10-31  7:21           ` Mike Rapoport
2019-12-05 15:34           ` Mike Rapoport
2019-12-08 14:10             ` [PATCH] mm: extend memfd with ability to create secret memory kbuild test robot
2019-10-29 11:25 ` [PATCH RFC] mm: add MAP_EXCLUSIVE to create exclusive user mappings Reshetova, Elena
2019-10-29 15:13   ` Tycho Andersen
2019-10-29 17:03   ` Andy Lutomirski
2019-10-29 17:37     ` Alan Cox
2019-10-29 17:43     ` James Bottomley
2019-10-29 18:10       ` Andy Lutomirski

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