linux-kernel - Re: [PATCH] kvm: Faults which trigger IO release the mmap

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Wed, 17 Sep 2014 14:42:15 +0300
From:	Gleb Natapov <gleb@...nel.org>
To:	Radim Krčmář <rkrcmar@...hat.com>
Cc:	Andres Lagar-Cavilla <andreslc@...gle.com>,
	Gleb Natapov <gleb@...hat.com>, Rik van Riel <riel@...hat.com>,
	Peter Zijlstra <peterz@...radead.org>,
	Mel Gorman <mgorman@...e.de>,
	Andy Lutomirski <luto@...capital.net>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Andrea Arcangeli <aarcange@...hat.com>,
	Sasha Levin <sasha.levin@...cle.com>,
	Jianyu Zhan <nasa4836@...il.com>,
	Paul Cassella <cassella@...y.com>,
	Hugh Dickins <hughd@...gle.com>,
	Peter Feiner <pfeiner@...gle.com>, kvm@...r.kernel.org,
	linux-kernel@...r.kernel.org, linux-mm@...ck.org
Subject: Re: [PATCH] kvm: Faults which trigger IO release the mmap_sem

On Wed, Sep 17, 2014 at 01:27:14PM +0200, Radim Krčmář wrote:
> 2014-09-17 13:26+0300, Gleb Natapov:
> > For async_pf_execute() you do not need to even retry. Next guest's page fault
> > will retry it for you.
> 
> Wouldn't that be a waste of vmentries?
This is how it will work with or without this second gup. Page is not
mapped into a shadow page table on this path, it happens on a next fault.

--
			Gleb.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/