linux-kernel - Re: [PATCH 3/3] x86: context_tracking: avoid irq_save/irq

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, 28 Oct 2015 15:51:34 +0100
From:	Paolo Bonzini <pbonzini@...hat.com>
To:	Andy Lutomirski <luto@...capital.net>
Cc:	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	kvm list <kvm@...r.kernel.org>,
	Andy Lutomirski <luto@...nel.org>,
	Frederic Weisbecker <fweisbec@...il.com>,
	Rik van Riel <riel@...hat.com>,
	Paul McKenney <paulmck@...ux.vnet.ibm.com>
Subject: Re: [PATCH 3/3] x86: context_tracking: avoid irq_save/irq_restore on
 kernel entry and exit



On 28/10/2015 06:22, Andy Lutomirski wrote:
>> > called by guest_enter and guest_exit.
>> >
>> > Use the previously introduced __context_tracking_entry and
>> > __context_tracking_exit.
> x86 isn't ready for this yet.  We could do a quick-and-dirty fix with
> explicit IRQs-on-and-off much protected by the static key, or we could
> just wait until I finish the syscall cleanup.  I favor the latter, but
> you're all welcome to do the former and I'll review it.

Or we could just do save/restore for the only call that doesn't ensure
that interrupts are disabled (syscall_trace_phase1 or whatever it's called).

But two days from the merge window, I also favor waiting until 4.5.

Paolo
--
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/