linux-kernel - Re: [PATCH v2 1/6] kvm: Pass kvm

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]

Message-ID: <20120628185109.16da81d3@BR9GNB5Z>
Date:	Thu, 28 Jun 2012 18:51:09 +0200
From:	Cornelia Huck <cornelia.huck@...ibm.com>
To:	"Michael S. Tsirkin" <mst@...hat.com>
Cc:	Alex Williamson <alex.williamson@...hat.com>, avi@...hat.com,
	kvm@...r.kernel.org, linux-kernel@...r.kernel.org,
	jan.kiszka@...mens.com
Subject: Re: [PATCH v2 1/6] kvm: Pass kvm_irqfd to functions

On Thu, 28 Jun 2012 15:09:49 +0300
"Michael S. Tsirkin" <mst@...hat.com> wrote:

> On Thu, Jun 28, 2012 at 02:00:41PM +0200, Cornelia Huck wrote:
> > On Thu, 28 Jun 2012 12:34:43 +0300
> > "Michael S. Tsirkin" <mst@...hat.com> wrote:
> > 
> > > On Thu, Jun 28, 2012 at 11:03:16AM +0200, Cornelia Huck wrote:
> > 
> > > > How about something like this as parameter for the new ioctl?
> > > > 
> > > > struct kvm_irqfd2 {
> > > > 	__u32 fd;
> > > > 	__u32 flags;  /* for things like deassign */
> > > > 	__u64 type;   /* determines the payload */
> > > > 	union {
> > > > 		/* type traditional */
> > > > 		struct {
> > > > 			__u32 gsi;
> > > > 		} trad;
> > > > 		/* type s390 */
> > > > 		struct {
> > > > 			__u32 int_type;
> > > > 			__u32 parm;
> > > > 			__u64 parm64;
> > > > 		} s390;
> > > > 		__u8 pad[20];
> > > > 	};
> > > > }
> > > > 
> > > > This could be combined with an arch or a per-kvm callback to keep the
> > > > generic code clean of architecture dependencies.
> > > > 
> > > > Cornelia
> > > 
> > > Looks a bit weird - shouldn't all this be part of gsi routing?
> > > But no idea really, I don't see the big picture here.
> > > 
> > 
> > Well, on s390 we don't have anything like "gsi routing" (I'm not even
> > really sure what that is).
> 
> I really mean kvm_irq_routing. This has options for
> irqchip, msi, I guess we can add more.

I stared at irq_comm.c for a bit and it seems to fulfill a purpose
similar to arch/s390/kvm/interrupt.c (although it looks more static).
But I don't really see how they could fit together easily.

> 
> 
> > My understanding is the following:
> > 
> > - Basically, we want to notify the guest for a virtqueue.
> > - For this, we want to inject an interrupt for the associated device.
> > - On x86, this means raising an interrupt on an interrupt line, as
> >   specified by some kind of number.
> 
> Not just that: for MSI we pass in data encoding priority
> destination etc.
> 
> > - On s390, we need some more information to (a) identify the device and
> >   (b) additional information that needs to be transmitted for an
> >   interrupt (device specific). (This is what basically goes into struct
> >   kvm_s390_interrupt, which I reproduced in the s390 part.)
> > 
> > Cornelia
> 
> Is this b mostly static or does it change for each interrupt?

For Linux guests it will be static, although the architecture would
allow for changing (some of) it.

Cornelia

--
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/