Linux-mm Archive on lore.kernel.org
 help / color / mirror / Atom feed
From: "Yanjun.Zhu" <yanjun.zhu@linux.dev>
To: Vipin Sharma <vipinsh@google.com>,
	kexec@lists.infradead.org, linux-kernel@vger.kernel.org,
	linux-doc@vger.kernel.org, kvm@vger.kernel.org,
	linux-mm@kvack.org, linux-kselftest@vger.kernel.org
Cc: ajayachandra@nvidia.com, alex@shazbot.org, amastro@fb.com,
	ankita@nvidia.com, apopple@nvidia.com, bhelgaas@google.com,
	chrisl@kernel.org, christian.koenig@amd.com, corbet@lwn.net,
	dmatlack@google.com, graf@amazon.com,
	jacob.pan@linux.microsoft.com, jgg@nvidia.com, jgg@ziepe.ca,
	jrhilke@google.com, julianr@linux.ibm.com, kees@kernel.org,
	kevin.tian@intel.com, leon@kernel.org, leonro@nvidia.com,
	lukas@wunner.de, mattev@meta.com, michal.winiarski@intel.com,
	parav@nvidia.com, pasha.tatashin@soleen.com, praan@google.com,
	pratyush@kernel.org, rananta@google.com, rientjes@google.com,
	rodrigo.vivi@intel.com, rppt@kernel.org, saeedm@nvidia.com,
	schnelle@linux.ibm.com, skhan@linuxfoundation.org,
	skhawaja@google.com, vivek.kasireddy@intel.com, witu@nvidia.com,
	yi.l.liu@intel.com
Subject: Re: [PATCH v5 00/20] vfio/pci: Base Live Update support for VFIO
Date: Thu, 16 Jul 2026 18:22:07 -0700	[thread overview]
Message-ID: <8fd94fad-e457-4839-9e41-ae257a138bee@linux.dev> (raw)
In-Reply-To: <2c03ac97-60a6-4352-a942-27dcebae8d22@linux.dev>

[-- Attachment #1: Type: text/plain, Size: 8726 bytes --]


On 7/16/26 4:24 PM, Yanjun.Zhu wrote:
>
>
> On 7/14/26 8:14 AM, Vipin Sharma wrote:
>> Hello,
>>
>> This series can be found on Github:
>>
>>    https://github.com/shvipin/linux vfio/liveupdate/v5
>>
>> This series provides the base support to enable Live Update feature for
>> VFIO PCI devices using the Live Update Orchestrator (LUO) and Kexec
>> Handover (KHO).
>>
>> Overview
>> --------
>>
>> This series makes the following changes to support VFIO Live Update:
>>
>>   - Puts VFIO Live Update support behind the CONFIG_VFIO_PCI_LIVEUPDATE
>>     config option (which requires CONFIG_VFIO_DEVICE_CDEV).
>>   - Preserves VFIO cdev device FDs across a kexec Live Update session via
>>     LUO/KHO.
>>   - Enforces that incoming preserved devices can only be retrieved via
>>     LIVEUPDATE_SESSION_RETRIEVE_FD post-kexec (preventing legacy
>>     group/cdev opens from accessing uninitialized state).
>>   - Quiesces the device prior to kexec in freeze() by resetting hardware,
>>     disabling bus mastering, and marking the device frozen to reject
>>     post-freeze IO/MMIO.
>>   - Includes VFIO selftests (uapi & kexec tests with continuous DMA
>>     checks) and kernel documentation.
>>
>> VFIO PCI Live Update Roadmap
>> ----------------------------
>>
>> We are planning to add VFIO PCI Live Update support in phases. Since full
>> support of this feature will come in phase, VFIO PCI Liveupdate is
>> controlled by CONFIG_VFIO_PCI_LIVEUPDATE config option.
>>
>> This series is phase 1 below:
>>
>>   1. PCIe function (non-VF) preserved across Live Update without changing
>>      BDF
>>   2. PCIe function (non-VF) preserved across Live Update without resetting
>>   3. PCIe function (non-VF) preserved across Live Update with continuous
>>      DMA (noiommu)
>>   4. PCIe function (non-VF) preserved across Live Update with continuous
>>      DMA (iommufd)
>>   5. PCIe VF preserved across Live Update with continuous DMA (iommufd)
>>
>> Dependencies
>> ------------
>>
>> This series has following dependencies as shown in the diagram
>>
>>      |---------------------------|
>>      |         VFIO v5           |  <--- Sent in this series.
>>      |---------------------------|
>>      |  Liveupdate Selftests[1]  |
>>      |---------------------------|
>>      |        PCI v7 [2]         |
>>      |---------------------------|
>>
>> [1]https://lore.kernel.org/all/20260511201155.1488670-1-vipinsh@google.com/
>>      These selftests changes are needed by other selftests also (iommu,
>>      kvm), so, I have sent them separately.
>>
>> [2]https://lore.kernel.org/linux-pci/20260710212616.1351130-1-dmatlack@google.com/
>>      This is the PCI v7, which adds the live update support in PCI core.
>>
>> Github branch I have mentioned at the top has all of these dependencies.
>>
>> Testing
>> -------
>>
>> Tested using VFIO Live Update selftests in both QEMU and bare-metal
>> environment (Intel DSA PCIe device).
>
> I want to make tests VFIO Live Update selftests in QEMU. But how to 
> select a PCIe device?
>
> what device do the PCI ID 0000:00:04.0 and 0000:6a:01.0 mean in the 
> following testcase?
>
In my qemu,

00:04.0 System peripheral: InnoTek Systemberatung GmbH VirtualBox Guest 
Service
     Control: I/O+ Mem+ BusMaster- SpecCycle- MemWINV- VGASnoop- ParErr- 
Stepping- SERR- FastB2B- DisINTx-
     Status: Cap- 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- 
<TAbort- <MAbort- >SERR- <PERR- INTx-
     Interrupt: pin A routed to IRQ 20
     Region 0: I/O ports at d040 [size=32]
     Region 1: Memory at f0400000 (32-bit, non-prefetchable) [size=4M]
     Region 2: Memory at f0800000 (32-bit, prefetchable) [size=16K]
     Kernel driver in use: vboxguest
     Kernel modules: vboxguest

I am wondering if the above pci device can work well with this patch set 
or not.

Zhu Yanjun

> Zhu Yanjun
>
>>    $ ./setup.sh 0000:00:04.0
>>    $ ./vfio_pci_liveupdate_kexec_test --stage 1 0000:6a:01.0
>>    $ kexec --reuse-cmdline -l -s /boot/vmlinuz
>>    $ kexec -e
>>    $ ./setup.sh 0000:00:04.0
>>    $ ./vfio_pci_liveupdate_kexec_test --stage 2 0000:6a:01.0
>>
>> Kernel command line options used:
>>    - liveupdate=on
>>    - kho=on
>>    - vfio_iommu_type1.allow_unsafe_interrupts=Y
>>    - vfio_pci.enable_sriov=Y
>>    - vfio_pci.disable_denylist=Y
>>    - vfio.enable_unsafe_noiommu_mode=Y
>>
>>
>> Changelog
>> ---------
>>
>> v5:
>>   - Addressed Sashiko feedback.
>>   - Removed condition to disable CONFIG_VFIO_PCI_DMABUF.
>>   - Expanded vfio_find_device() helper to safely discover a registered
>>     vfio_device by matching criteria. Internal Sashiko instance found
>>     data race.
>>   - Updated selftests to latest changes in VFIO selftests.
>>   - Rebased on top of PCI Live Update series v7.
>>
>> v4:https://lore.kernel.org/kvm/20260511234802.2280368-1-vipinsh@google.com/
>>
>> v3:https://lore.kernel.org/kvm/20260323235817.1960573-1-dmatlack@google.com/
>>
>> v2:https://lore.kernel.org/kvm/20260129212510.967611-1-dmatlack@google.com/
>>
>> v1:https://lore.kernel.org/kvm/20251126193608.2678510-1-dmatlack@google.com/
>>
>> rfc:https://lore.kernel.org/kvm/20251018000713.677779-1-vipinsh@google.com/
>>
>>
>> David Matlack (7):
>>    vfio: Enforce preserved devices are retrieved via
>>      LIVEUPDATE_SESSION_RETRIEVE_FD
>>    docs: liveupdate: Add documentation for VFIO PCI
>>    vfio: selftests: Add vfio_pci_liveupdate_uapi_test
>>    vfio: selftests: Add Makefile support for TEST_GEN_PROGS_EXTENDED
>>    vfio: selftests: Expose iommu_modes to tests
>>    vfio: selftests: Verify that opening VFIO device fails during Live
>>      Update
>>    vfio: selftests: Add continuous DMA to vfio_pci_liveupdate_kexec_test
>>
>> Vipin Sharma (13):
>>    vfio/pci: Factor out the reset logic in VFIO PCI device close path
>>    vfio: Export various helpers from VFIO
>>    vfio/pci: Export vfio_pci_dma_buf_move for vfio-pci module
>>    liveupdate: Export symbols needed by modules
>>    vfio/pci: Register a file handler with Live Update Orchestrator
>>    vfio/pci: Preserve vfio-pci device files across Live Update
>>    vfio: Introduce vfio_find_device() helper
>>    vfio: Refactor vfio_device_fops_cdev_open()
>>    vfio: Add API to open cdev device for Live Update restore
>>    vfio/pci: Retrieve preserved device files after Live Update
>>    vfio: selftests: Build liveupdate library in VFIO selftests
>>    vfio: selftests: Initialize vfio_pci_device using a VFIO cdev FD
>>    vfio: selftests: Add vfio_pci_liveupdate_kexec_test
>>
>>   Documentation/core-api/liveupdate.rst         |   1 +
>>   .../driver-api/vfio_pci_liveupdate.rst        |  23 ++
>>   MAINTAINERS                                   |   2 +
>>   drivers/vfio/device_cdev.c                    |  67 +++-
>>   drivers/vfio/group.c                          |   9 +
>>   drivers/vfio/pci/Kconfig                      |  12 +
>>   drivers/vfio/pci/Makefile                     |   1 +
>>   drivers/vfio/pci/vfio_pci.c                   |  13 +-
>>   drivers/vfio/pci/vfio_pci_config.c            |   3 +
>>   drivers/vfio/pci/vfio_pci_core.c              | 119 +++---
>>   drivers/vfio/pci/vfio_pci_dmabuf.c            |   1 +
>>   drivers/vfio/pci/vfio_pci_liveupdate.c        | 340 ++++++++++++++++++
>>   drivers/vfio/pci/vfio_pci_priv.h              |  28 ++
>>   drivers/vfio/vfio.h                           |  18 +
>>   drivers/vfio/vfio_main.c                      |  67 +++-
>>   include/linux/kho/abi/vfio_pci.h              |  43 +++
>>   include/linux/vfio.h                          |  12 +
>>   include/linux/vfio_pci_core.h                 |   3 +
>>   kernel/liveupdate/luo_file.c                  |   2 +
>>   tools/testing/selftests/vfio/Makefile         |  23 +-
>>   .../vfio/lib/include/libvfio/iommu.h          |   2 +
>>   .../lib/include/libvfio/vfio_pci_device.h     |   3 +
>>   tools/testing/selftests/vfio/lib/iommu.c      |   4 +-
>>   .../selftests/vfio/lib/vfio_pci_device.c      |  25 +-
>>   .../vfio/vfio_pci_liveupdate_kexec_test.c     | 256 +++++++++++++
>>   .../vfio/vfio_pci_liveupdate_uapi_test.c      |  97 +++++
>>   26 files changed, 1097 insertions(+), 77 deletions(-)
>>   create mode 100644 Documentation/driver-api/vfio_pci_liveupdate.rst
>>   create mode 100644 drivers/vfio/pci/vfio_pci_liveupdate.c
>>   create mode 100644 include/linux/kho/abi/vfio_pci.h
>>   create mode 100644 tools/testing/selftests/vfio/vfio_pci_liveupdate_kexec_test.c
>>   create mode 100644 tools/testing/selftests/vfio/vfio_pci_liveupdate_uapi_test.c
>>
>>
>> base-commit: cbf37fff757e87376e80e11a8378393a8f25145f
>> prerequisite-patch-id: 85705fb54d3065efe1d87ab4b69e828a9f3404e7
>> prerequisite-patch-id: a33ae79b5fc0259bd013b430c18cc3d14a678599

[-- Attachment #2: Type: text/html, Size: 10464 bytes --]

      reply	other threads:[~2026-07-17  1:22 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-07-14 15:14 [PATCH v5 00/20] vfio/pci: Base Live Update support for VFIO Vipin Sharma
2026-07-14 15:14 ` [PATCH v5 01/20] vfio/pci: Factor out the reset logic in VFIO PCI device close path Vipin Sharma
2026-07-14 15:14 ` [PATCH v5 02/20] vfio: Export various helpers from VFIO Vipin Sharma
2026-07-14 15:14 ` [PATCH v5 03/20] vfio/pci: Export vfio_pci_dma_buf_move for vfio-pci module Vipin Sharma
2026-07-14 15:14 ` [PATCH v5 04/20] liveupdate: Export symbols needed by modules Vipin Sharma
2026-07-14 15:14 ` [PATCH v5 05/20] vfio/pci: Register a file handler with Live Update Orchestrator Vipin Sharma
2026-07-14 15:14 ` [PATCH v5 06/20] vfio/pci: Preserve vfio-pci device files across Live Update Vipin Sharma
2026-07-14 15:14 ` [PATCH v5 07/20] vfio: Introduce vfio_find_device() helper Vipin Sharma
2026-07-14 15:14 ` [PATCH v5 08/20] vfio: Refactor vfio_device_fops_cdev_open() Vipin Sharma
2026-07-14 15:14 ` [PATCH v5 09/20] vfio: Add API to open cdev device for Live Update restore Vipin Sharma
2026-07-14 15:14 ` [PATCH v5 10/20] vfio/pci: Retrieve preserved device files after Live Update Vipin Sharma
2026-07-14 15:14 ` [PATCH v5 11/20] vfio: Enforce preserved devices are retrieved via LIVEUPDATE_SESSION_RETRIEVE_FD Vipin Sharma
2026-07-14 15:14 ` [PATCH v5 12/20] docs: liveupdate: Add documentation for VFIO PCI Vipin Sharma
2026-07-14 15:14 ` [PATCH v5 13/20] vfio: selftests: Build liveupdate library in VFIO selftests Vipin Sharma
2026-07-14 15:14 ` [PATCH v5 14/20] vfio: selftests: Add vfio_pci_liveupdate_uapi_test Vipin Sharma
2026-07-14 15:15 ` [PATCH v5 15/20] vfio: selftests: Initialize vfio_pci_device using a VFIO cdev FD Vipin Sharma
2026-07-14 15:15 ` [PATCH v5 16/20] vfio: selftests: Add Makefile support for TEST_GEN_PROGS_EXTENDED Vipin Sharma
2026-07-14 15:15 ` [PATCH v5 17/20] vfio: selftests: Add vfio_pci_liveupdate_kexec_test Vipin Sharma
2026-07-14 15:15 ` [PATCH v5 18/20] vfio: selftests: Expose iommu_modes to tests Vipin Sharma
2026-07-14 15:15 ` [PATCH v5 19/20] vfio: selftests: Verify that opening VFIO device fails during Live Update Vipin Sharma
2026-07-14 15:15 ` [PATCH v5 20/20] vfio: selftests: Add continuous DMA to vfio_pci_liveupdate_kexec_test Vipin Sharma
2026-07-16 23:24 ` [PATCH v5 00/20] vfio/pci: Base Live Update support for VFIO Yanjun.Zhu
2026-07-17  1:22   ` Yanjun.Zhu [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=8fd94fad-e457-4839-9e41-ae257a138bee@linux.dev \
    --to=yanjun.zhu@linux.dev \
    --cc=ajayachandra@nvidia.com \
    --cc=alex@shazbot.org \
    --cc=amastro@fb.com \
    --cc=ankita@nvidia.com \
    --cc=apopple@nvidia.com \
    --cc=bhelgaas@google.com \
    --cc=chrisl@kernel.org \
    --cc=christian.koenig@amd.com \
    --cc=corbet@lwn.net \
    --cc=dmatlack@google.com \
    --cc=graf@amazon.com \
    --cc=jacob.pan@linux.microsoft.com \
    --cc=jgg@nvidia.com \
    --cc=jgg@ziepe.ca \
    --cc=jrhilke@google.com \
    --cc=julianr@linux.ibm.com \
    --cc=kees@kernel.org \
    --cc=kevin.tian@intel.com \
    --cc=kexec@lists.infradead.org \
    --cc=kvm@vger.kernel.org \
    --cc=leon@kernel.org \
    --cc=leonro@nvidia.com \
    --cc=linux-doc@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-kselftest@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=lukas@wunner.de \
    --cc=mattev@meta.com \
    --cc=michal.winiarski@intel.com \
    --cc=parav@nvidia.com \
    --cc=pasha.tatashin@soleen.com \
    --cc=praan@google.com \
    --cc=pratyush@kernel.org \
    --cc=rananta@google.com \
    --cc=rientjes@google.com \
    --cc=rodrigo.vivi@intel.com \
    --cc=rppt@kernel.org \
    --cc=saeedm@nvidia.com \
    --cc=schnelle@linux.ibm.com \
    --cc=skhan@linuxfoundation.org \
    --cc=skhawaja@google.com \
    --cc=vipinsh@google.com \
    --cc=vivek.kasireddy@intel.com \
    --cc=witu@nvidia.com \
    --cc=yi.l.liu@intel.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox