linux-kernel - Re: [PATCH 1/7] KVM: api: add kvm_irq_routing_extended

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:	Mon, 6 Jul 2015 13:51:24 +0200
From:	Paolo Bonzini <pbonzini@...hat.com>
To:	Andre Przywara <andre.przywara@....com>,
	Christoffer Dall <christoffer.dall@...aro.org>
Cc:	Pavel Fedin <p.fedin@...sung.com>,
	"'Eric Auger'" <eric.auger@...aro.org>,
	"eric.auger@...com" <eric.auger@...com>,
	"linux-arm-kernel@...ts.infradead.org" 
	<linux-arm-kernel@...ts.infradead.org>,
	Marc Zyngier <Marc.Zyngier@....com>,
	"kvmarm@...ts.cs.columbia.edu" <kvmarm@...ts.cs.columbia.edu>,
	"kvm@...r.kernel.org" <kvm@...r.kernel.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 1/7] KVM: api: add kvm_irq_routing_extended_msi



On 06/07/2015 13:23, Andre Przywara wrote:
> Hi Paolo,
> 
> thanks for looking at this!
> 
> On 06/07/15 12:07, Paolo Bonzini wrote:
>>
>>
>> On 06/07/2015 12:37, Christoffer Dall wrote:
>>> I don't view it as 'the kernel requires this' but as 'the kernel will
>>> not complain with arbitrary error code if you set the devid flag'
>>> capability, and it's up to userspace (as usual) to provide the correct
>>> arguments for things to work, and up to the kernel to ensure we don't
>>> crash the system etc.
>>>
>>> Thus, if you want to advertise it as a capability, I would rather call
>>> it KVM_CAP_MSI_DEVID.
>>
>> I agree.  Does userspace know that ITS guests always require devid?
> 
> Well, as we are about to implement this: yes. But the issue is that MSI
> injection and GSI routing code is generic PCI code in userland (at least
> in kvmtool, guess in QEMU, too), so I don't want to pull in any kind of
> ARM specific code in there. The idea is to always provide the device ID
> from the PCI code (for PCI devices it's just the B/D/F triplet), but
> only send it to the kernel if needed. Querying a KVM capability is
> perfectly fine for this IMO.

Yes, I agree.

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/