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]
Message-ID: <ZyimtM-sQSmRblpm@kernel.org>
Date: Mon, 4 Nov 2024 12:49:24 +0200
From: Mike Rapoport <rppt@...nel.org>
To: Jason Gunthorpe <jgg@...pe.ca>
Cc: "Gowans, James" <jgowans@...zon.com>,
	"quic_eberman@...cinc.com" <quic_eberman@...cinc.com>,
	"kvm@...r.kernel.org" <kvm@...r.kernel.org>,
	"brauner@...nel.org" <brauner@...nel.org>,
	"anthony.yznaga@...cle.com" <anthony.yznaga@...cle.com>,
	"steven.sistare@...cle.com" <steven.sistare@...cle.com>,
	"akpm@...ux-foundation.org" <akpm@...ux-foundation.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"seanjc@...gle.com" <seanjc@...gle.com>,
	"Durrant, Paul" <pdurrant@...zon.co.uk>,
	"pbonzini@...hat.com" <pbonzini@...hat.com>,
	"linux-mm@...ck.org" <linux-mm@...ck.org>,
	"Woodhouse, David" <dwmw@...zon.co.uk>,
	"Saenz Julienne, Nicolas" <nsaenz@...zon.es>,
	"viro@...iv.linux.org.uk" <viro@...iv.linux.org.uk>,
	"Graf (AWS), Alexander" <graf@...zon.de>,
	"jack@...e.cz" <jack@...e.cz>,
	"linux-fsdevel@...r.kernel.org" <linux-fsdevel@...r.kernel.org>
Subject: Re: [PATCH 05/10] guestmemfs: add file mmap callback

On Fri, Nov 01, 2024 at 10:42:02AM -0300, Jason Gunthorpe wrote:
> On Fri, Nov 01, 2024 at 01:01:00PM +0000, Gowans, James wrote:
> 
> > Thanks Jason, that sounds perfect. I'll work on the next rev which will:
> > - expose a filesystem which owns reserved/persistent memory, just like
> > this patch.
> 
> Is this step needed?
> 
> If the guest memfd is already told to get 1G pages in some normal way,
> why do we need a dedicated pool just for the KHO filesystem?
> 
> Back to my suggestion, can't KHO simply freeze the guest memfd and
> then extract the memory layout, and just use the normal allocator?
> 
> Or do you have a hard requirement that only KHO allocated memory can
> be preserved across kexec?

KHO does not allocate memory, it gets the ranges to preserve, makes sure
they are not overwritten during kexec and can be retrieved by the second
kernel.
For KHO it does not matter if the memory comes from a normal or a special
allocator.
 
> Jason

-- 
Sincerely yours,
Mike.

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ