linux-kernel - Re: [RFC PATCH v1.9 00/14] livepatch: hybrid consistency model

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:	Thu, 7 Apr 2016 14:10:30 +0200
From:	Petr Mladek <pmladek@...e.com>
To:	Josh Poimboeuf <jpoimboe@...hat.com>
Cc:	Jiri Kosina <jikos@...nel.org>, Jessica Yu <jeyu@...hat.com>,
	Miroslav Benes <mbenes@...e.cz>, linux-kernel@...r.kernel.org,
	live-patching@...r.kernel.org, Vojtech Pavlik <vojtech@...e.com>
Subject: Re: [RFC PATCH v1.9 00/14] livepatch: hybrid consistency model

On Fri 2016-03-25 14:34:47, Josh Poimboeuf wrote:
> TODO:
> - try ftrace handler switching idea from v1 cover letter

I have had a discussion about it with Mirek. This would help with
kthreads. If they are sleeping in a patched function, we wake
them up, this will help to migrate them before they get asleep again.

But it might be quite tricky. We must make sure to avoid a deadlock.
We probably should not check the stack in atomic context or
in time sensitive functions.

An alternative would be to check the stack and try migration
when the process goes into a sleep. It is a location where
we should not be afraid of any deadlocks or slight delay.
There should be high changes for a successful migration with
a minimal impact on the system throughput.

Best Regards,
Petr