linux-kernel - Re: [PATCH 3/4 V13] Add ioctl for KVM_KVMCLOCK

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: <4F3D0E9C.8030302@redhat.com>
Date:	Thu, 16 Feb 2012 16:11:40 +0200
From:	Avi Kivity <avi@...hat.com>
To:	Eric B Munson <emunson@...bm.net>
CC:	mingo@...hat.com, hpa@...or.com, ryanh@...ux.vnet.ibm.com,
	aliguori@...ibm.com, mtosatti@...hat.com, kvm@...r.kernel.org,
	linux-arch@...r.kernel.org, x86@...nel.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH 3/4 V13] Add ioctl for KVM_KVMCLOCK_CTRL

On 02/08/2012 05:07 PM, Eric B Munson wrote:
> Now that we have a flag that will tell the guest it was suspended, create an
> interface for that communication using a KVM ioctl.
>
> +
> +Capability: KVM_CAP_KVMCLOCK_CTRL
> +Architectures: Any that implement pvclocks (currently x86 only)
> +Type: vcpu ioctl
> +Parameters: None
> +Returns: 0 on success, -1 on error
> +
> +This signals to the host kernel that the specified guest is being paused by
> +userspace.  The host will set a flag in the pvclock structure that is checked
> +from the soft lockup watchdog.  

This needs to be expanded.  There is a protocol between the host and
guest that needs to be documented, including the requirement to use a
single instruction (or ll/sc) to clear the flag.  See
Documentation/virtual/kvm/msr.txt

> This ioctl can be called during pause or
> +unpause.
> +

After pausing the vcpu, but before resuming it.


-- 
error compiling committee.c: too many arguments to function

--
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/