linux-kernel - Re: [PATCH v2 5/7] KVM: Introduce PV kick in flush tlb

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 for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20120703080713.GA12579@amt.cnet>
Date:	Tue, 3 Jul 2012 05:07:13 -0300
From:	Marcelo Tosatti <mtosatti@...hat.com>
To:	"Nikunj A. Dadhania" <nikunj@...ux.vnet.ibm.com>
Cc:	peterz@...radead.org, mingo@...e.hu, avi@...hat.com,
	raghukt@...ux.vnet.ibm.com, kvm@...r.kernel.org,
	linux-kernel@...r.kernel.org, x86@...nel.org, jeremy@...p.org,
	vatsa@...ux.vnet.ibm.com, hpa@...or.com
Subject: Re: [PATCH v2 5/7] KVM: Introduce PV kick in flush tlb

On Mon, Jun 04, 2012 at 10:38:17AM +0530, Nikunj A. Dadhania wrote:
> In place of looping continuously introduce a halt if we do not succeed
> after some time.
> 
> For vcpus that were running an IPI is sent.  In case, it went to sleep
> between this, we will be doing flush_on_enter(harmless). But as a
> flush IPI was already sent, that will be processed in ipi handler,
> this might result into something undesireable, i.e. It might clear the
> flush_mask of a new request.
> 
> So after sending an IPI and waiting for a while, do a halt and wait
> for a kick from the last vcpu.
> 
> Signed-off-by: Srivatsa Vaddagiri <vatsa@...ux.vnet.ibm.com>
> Signed-off-by: Nikunj A. Dadhania <nikunj@...ux.vnet.ibm.com>

Again, was it determined that this is necessary from data of 
benchmarking on the in-guest-mode/out-guest-mode patch?

--
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/