linux-kernel - about the time consuming kvm_vcpu

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

Message-ID: <F2CBF3009FA73547804AE4C663CAB28E58A387@shsmsx102.ccr.corp.intel.com>
Date:	Thu, 6 Aug 2015 03:46:47 +0000
From:	"Li, Liang Z" <liang.z.li@...el.com>
To:	Paolo Bonzini <pbonzini@...hat.com>,
	'Juan Quintela' <quintela@...hat.com>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
CC:	"Zhang, Yang Z" <yang.z.zhang@...el.com>,
	"kvm@...r.kernel.org" <kvm@...r.kernel.org>
Subject: about the time consuming kvm_vcpu_ioctl issue in rhel kernel

Hi Paolo & Juan,

I found some of the kvm_vcpu_ioctl operation takes about more than 10ms with the 3.10.0-229.el7.x86_64 kernel, which prolong the VM service downtime when doing live migration about 20~30ms.
This happened when doing the KVM_KVMCLOCK_CTRL ioctl. It's worse if more VCPUs used by guest(4VPUs in my test). The upstream kernel does not have this issue because of the patch 7a72f7a140bfd3,
 maybe this patch should be backported to the el7 kernel.

Liang
--
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/