Re: [RFC 0/4] vfio-pci/zdev: Fixing s390 vfio-pci ISM support

2020-12-22 Thread Cornelia Huck
On Thu, 17 Dec 2020 11:04:48 -0500 Matthew Rosato wrote: > On 12/17/20 7:59 AM, Cornelia Huck wrote: > > The basic question I have is whether it makes sense to specialcase the > > ISM device (can we even find out that we're dealing with an ISM device > > here?) to force the non-MIO instructions,

Re: [RFC 0/4] vfio-pci/zdev: Fixing s390 vfio-pci ISM support

2020-12-17 Thread Matthew Rosato
On 12/17/20 7:59 AM, Cornelia Huck wrote: On Fri, 11 Dec 2020 10:04:43 -0500 Matthew Rosato wrote: On 12/11/20 10:01 AM, Matthew Rosato wrote: On 12/11/20 9:35 AM, Cornelia Huck wrote: Let me summarize this to make sure I understand this new region correctly: - some devices may have

Re: [RFC 0/4] vfio-pci/zdev: Fixing s390 vfio-pci ISM support

2020-12-17 Thread Cornelia Huck
On Fri, 11 Dec 2020 10:04:43 -0500 Matthew Rosato wrote: > On 12/11/20 10:01 AM, Matthew Rosato wrote: > > On 12/11/20 9:35 AM, Cornelia Huck wrote: > >> Let me summarize this to make sure I understand this new region > >> correctly: > >> > >> - some devices may have relaxed alignment/length

Re: [RFC 0/4] vfio-pci/zdev: Fixing s390 vfio-pci ISM support

2020-12-11 Thread Matthew Rosato
On 12/11/20 10:01 AM, Matthew Rosato wrote: On 12/11/20 9:35 AM, Cornelia Huck wrote: On Thu, 10 Dec 2020 10:51:23 -0500 Matthew Rosato wrote: On 12/10/20 7:33 AM, Cornelia Huck wrote: On Wed,  9 Dec 2020 15:27:46 -0500 Matthew Rosato wrote: Today, ISM devices are completely disallowed for

Re: [RFC 0/4] vfio-pci/zdev: Fixing s390 vfio-pci ISM support

2020-12-11 Thread Matthew Rosato
On 12/11/20 9:35 AM, Cornelia Huck wrote: On Thu, 10 Dec 2020 10:51:23 -0500 Matthew Rosato wrote: On 12/10/20 7:33 AM, Cornelia Huck wrote: On Wed, 9 Dec 2020 15:27:46 -0500 Matthew Rosato wrote: Today, ISM devices are completely disallowed for vfio-pci passthrough as QEMU will

Re: [RFC 0/4] vfio-pci/zdev: Fixing s390 vfio-pci ISM support

2020-12-11 Thread Cornelia Huck
On Thu, 10 Dec 2020 10:51:23 -0500 Matthew Rosato wrote: > On 12/10/20 7:33 AM, Cornelia Huck wrote: > > On Wed, 9 Dec 2020 15:27:46 -0500 > > Matthew Rosato wrote: > > > >> Today, ISM devices are completely disallowed for vfio-pci passthrough as > >> QEMU will reject the device due to an

Re: [RFC 0/4] vfio-pci/zdev: Fixing s390 vfio-pci ISM support

2020-12-11 Thread Cornelia Huck
On Thu, 10 Dec 2020 17:14:24 +0100 Niklas Schnelle wrote: > On 12/10/20 4:51 PM, Matthew Rosato wrote: > > On 12/10/20 7:33 AM, Cornelia Huck wrote: > >> On Wed,  9 Dec 2020 15:27:46 -0500 > >> Matthew Rosato wrote: > >> > >>> Today, ISM devices are completely disallowed for vfio-pci

Re: [RFC 0/4] vfio-pci/zdev: Fixing s390 vfio-pci ISM support

2020-12-10 Thread Niklas Schnelle
On 12/10/20 4:51 PM, Matthew Rosato wrote: > On 12/10/20 7:33 AM, Cornelia Huck wrote: >> On Wed,  9 Dec 2020 15:27:46 -0500 >> Matthew Rosato wrote: >> >>> Today, ISM devices are completely disallowed for vfio-pci passthrough as >>> QEMU will reject the device due to an (inappropriate) MSI-X

Re: [RFC 0/4] vfio-pci/zdev: Fixing s390 vfio-pci ISM support

2020-12-10 Thread Matthew Rosato
On 12/10/20 7:33 AM, Cornelia Huck wrote: On Wed, 9 Dec 2020 15:27:46 -0500 Matthew Rosato wrote: Today, ISM devices are completely disallowed for vfio-pci passthrough as QEMU will reject the device due to an (inappropriate) MSI-X check. However, in an effort to enable ISM device

Re: [RFC 0/4] vfio-pci/zdev: Fixing s390 vfio-pci ISM support

2020-12-10 Thread Cornelia Huck
On Wed, 9 Dec 2020 15:27:46 -0500 Matthew Rosato wrote: > Today, ISM devices are completely disallowed for vfio-pci passthrough as > QEMU will reject the device due to an (inappropriate) MSI-X check. > However, in an effort to enable ISM device passthrough, I realized that the > manner in which

Re: [RFC 0/4] vfio-pci/zdev: Fixing s390 vfio-pci ISM support

2020-12-09 Thread Matthew Rosato
On 12/9/20 3:27 PM, Matthew Rosato wrote: Today, ISM devices are completely disallowed for vfio-pci passthrough as QEMU will reject the device due to an (inappropriate) MSI-X check. However, in an effort to enable ISM device passthrough, I realized that the manner in which ISM performs block

[RFC 0/4] vfio-pci/zdev: Fixing s390 vfio-pci ISM support

2020-12-09 Thread Matthew Rosato
Today, ISM devices are completely disallowed for vfio-pci passthrough as QEMU will reject the device due to an (inappropriate) MSI-X check. However, in an effort to enable ISM device passthrough, I realized that the manner in which ISM performs block write operations is highly incompatible with