Re: [Qemu-devel] [PATCH 0/2] virtio len fixes for qemu.

2015-03-19 Thread Rusty Russell
"Michael S. Tsirkin" writes: > On Mon, Mar 16, 2015 at 01:44:22PM +1030, Rusty Russell wrote: >> diff --git a/content.tex b/content.tex >> index 6ba079d..2c946a5 100644 >> --- a/content.tex >> +++ b/content.tex >> @@ -600,10 +600,19 @@ them: it is only written to by the device, and read by >> the

Re: [Qemu-devel] [PATCH 0/2] virtio len fixes for qemu.

2015-03-18 Thread Michael S. Tsirkin
On Wed, Mar 11, 2015 at 04:29:30PM +1030, Rusty Russell wrote: > The virtio 'used' ring describes descriptors which have been used. It > also says how many bytes have been written to the ring. For some cases, > this value is ignored by Linux guests, thus errors have not been noticed. > I was work

Re: [Qemu-devel] [PATCH 0/2] virtio len fixes for qemu.

2015-03-16 Thread Cornelia Huck
On Mon, 16 Mar 2015 06:03:24 +0100 "Michael S. Tsirkin" wrote: > On Mon, Mar 16, 2015 at 01:44:22PM +1030, Rusty Russell wrote: > > diff --git a/content.tex b/content.tex > > index 6ba079d..2c946a5 100644 > > --- a/content.tex > > +++ b/content.tex > > @@ -600,10 +600,19 @@ them: it is only writ

Re: [Qemu-devel] [PATCH 0/2] virtio len fixes for qemu.

2015-03-15 Thread Michael S. Tsirkin
On Mon, Mar 16, 2015 at 01:44:22PM +1030, Rusty Russell wrote: > "Michael S. Tsirkin" writes: > > On Fri, Mar 13, 2015 at 11:47:18AM +1030, Rusty Russell wrote: > >> Here's my proposed spec patch, which spells this out: > >> > >> diff --git a/content.tex b/content.tex > >> index 6ba079d..b6345a8

Re: [Qemu-devel] [PATCH 0/2] virtio len fixes for qemu.

2015-03-15 Thread Rusty Russell
"Michael S. Tsirkin" writes: > On Fri, Mar 13, 2015 at 11:47:18AM +1030, Rusty Russell wrote: >> Here's my proposed spec patch, which spells this out: >> >> diff --git a/content.tex b/content.tex >> index 6ba079d..b6345a8 100644 >> --- a/content.tex >> +++ b/content.tex >> @@ -600,10 +600,19 @@ t

Re: [Qemu-devel] [PATCH 0/2] virtio len fixes for qemu.

2015-03-13 Thread Michael S. Tsirkin
On Fri, Mar 13, 2015 at 11:47:18AM +1030, Rusty Russell wrote: > "Michael S. Tsirkin" writes: > > On Thu, Mar 12, 2015 at 11:34:35AM +1030, Rusty Russell wrote: > >> "Michael S. Tsirkin" writes: > >> > On Wed, Mar 11, 2015 at 10:06:40PM +1030, Rusty Russell wrote: > >> >> Each entry in th

Re: [Qemu-devel] [PATCH 0/2] virtio len fixes for qemu.

2015-03-12 Thread Rusty Russell
"Michael S. Tsirkin" writes: > On Thu, Mar 12, 2015 at 11:34:35AM +1030, Rusty Russell wrote: >> "Michael S. Tsirkin" writes: >> > On Wed, Mar 11, 2015 at 10:06:40PM +1030, Rusty Russell wrote: >> >> Each entry in the ring is a pair: \field{id} indicates the head >> >> entry of th

Re: [Qemu-devel] [PATCH 0/2] virtio len fixes for qemu.

2015-03-11 Thread Michael S. Tsirkin
On Thu, Mar 12, 2015 at 11:34:35AM +1030, Rusty Russell wrote: > "Michael S. Tsirkin" writes: > > On Wed, Mar 11, 2015 at 10:06:40PM +1030, Rusty Russell wrote: > >> Each entry in the ring is a pair: \field{id} indicates the head > >> entry of the descriptor chain describing the bu

Re: [Qemu-devel] [PATCH 0/2] virtio len fixes for qemu.

2015-03-11 Thread Rusty Russell
"Michael S. Tsirkin" writes: > On Wed, Mar 11, 2015 at 10:06:40PM +1030, Rusty Russell wrote: >> Each entry in the ring is a pair: \field{id} indicates the head >> entry of the descriptor chain describing the buffer (this >> matches an entry placed in the available ring by

Re: [Qemu-devel] [PATCH 0/2] virtio len fixes for qemu.

2015-03-11 Thread Michael S. Tsirkin
On Wed, Mar 11, 2015 at 10:06:40PM +1030, Rusty Russell wrote: > "Michael S. Tsirkin" writes: > > On Wed, Mar 11, 2015 at 02:47:47PM +0800, Fam Zheng wrote: > >> On Wed, 03/11 07:19, Michael S. Tsirkin wrote: > >> > On Wed, Mar 11, 2015 at 04:29:30PM +1030, Rusty Russell wrote: > >> > > The virtio

Re: [Qemu-devel] [PATCH 0/2] virtio len fixes for qemu.

2015-03-11 Thread Rusty Russell
"Michael S. Tsirkin" writes: > On Wed, Mar 11, 2015 at 02:47:47PM +0800, Fam Zheng wrote: >> On Wed, 03/11 07:19, Michael S. Tsirkin wrote: >> > On Wed, Mar 11, 2015 at 04:29:30PM +1030, Rusty Russell wrote: >> > > The virtio 'used' ring describes descriptors which have been used. It >> > > also

Re: [Qemu-devel] [PATCH 0/2] virtio len fixes for qemu.

2015-03-10 Thread Michael S. Tsirkin
On Wed, Mar 11, 2015 at 02:47:47PM +0800, Fam Zheng wrote: > On Wed, 03/11 07:19, Michael S. Tsirkin wrote: > > On Wed, Mar 11, 2015 at 04:29:30PM +1030, Rusty Russell wrote: > > > The virtio 'used' ring describes descriptors which have been used. It > > > also says how many bytes have been writte

Re: [Qemu-devel] [PATCH 0/2] virtio len fixes for qemu.

2015-03-10 Thread Fam Zheng
On Wed, 03/11 07:19, Michael S. Tsirkin wrote: > On Wed, Mar 11, 2015 at 04:29:30PM +1030, Rusty Russell wrote: > > The virtio 'used' ring describes descriptors which have been used. It > > also says how many bytes have been written to the ring. For some cases, > > this value is ignored by Linux

Re: [Qemu-devel] [PATCH 0/2] virtio len fixes for qemu.

2015-03-10 Thread Michael S. Tsirkin
On Wed, Mar 11, 2015 at 04:29:30PM +1030, Rusty Russell wrote: > The virtio 'used' ring describes descriptors which have been used. It > also says how many bytes have been written to the ring. For some cases, > this value is ignored by Linux guests, thus errors have not been noticed. > I was work

[Qemu-devel] [PATCH 0/2] virtio len fixes for qemu.

2015-03-10 Thread Rusty Russell
The virtio 'used' ring describes descriptors which have been used. It also says how many bytes have been written to the ring. For some cases, this value is ignored by Linux guests, thus errors have not been noticed. I was working on increasing the checking in Linux when I noticed this behaviour.