linux-kernel - Re: [Xen-devel] [PATCH v3] xen: Suspend ticks on all CPUs during suspend

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] [day] [month] [year] [list]

Date:	Wed, 29 Apr 2015 17:10:34 +0100
From:	David Vrabel <david.vrabel@...rix.com>
To:	Boris Ostrovsky <boris.ostrovsky@...cle.com>,
	<david.vrabel@...rix.com>, <konrad.wilk@...cle.com>
CC:	<xen-devel@...ts.xenproject.org>, <linux-kernel@...r.kernel.org>
Subject: Re: [Xen-devel] [PATCH v3] xen: Suspend ticks on all CPUs during
 suspend

On 28/04/15 23:46, Boris Ostrovsky wrote:
> Commit 77e32c89a711 ("clockevents: Manage device's state separately for
> the core") decouples clockevent device's modes from states. With this
> change when a Xen guest tries to resume, it won't be calling its
> set_mode op which needs to be done on each VCPU in order to make the
> hypervisor aware that we are in oneshot mode.
> 
> This happens because clockevents_tick_resume() (which is an intermediate
> step of resuming ticks on a processor) doesn't call clockevents_set_state()
> anymore and because during suspend clockevent devices on all VCPUs (except
> for the one doing the suspend) are left in ONESHOT state. As result, during
> resume the clockevents state machine will assume that device is already
> where it should be and doesn't need to be updated.
> 
> To avoid this problem we should suspend ticks on all VCPUs during
> suspend.

Applied to for-linus-4.1b, thanks.

David
--
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/