在 2026/7/14 8:15, Vipin Sharma 写道:
Add a selftest to exercise preserving a vfio-pci device across a Live
Update. For now the test is extremely simple and just verifies that the
device file can be preserved and retrieved. In the future this test will
be extended to verify more parts about device preservation as they are
implemented.
This test is added to TEST_GEN_PROGS_EXTENDED since it must be run
manually along with a kexec.
To run this test manually:
$ tools/testing/selftests/vfio/scripts/setup.sh 0000:00:04.0
$ tools/testing/selftests/vfio/vfio_pci_liveupdate_kexec_test --stage 1
0000:00:04.0
# ls /dev
autofs disk iommu mem rtc0 tty10 tty21
tty32 tty43 tty54 tty8 ttyS18 ttyS29 uinput vcs6 vcsu4
virtio-ports
block dma_heap kmsg mqueue sg0 tty11 tty22
tty33 tty44 tty55 tty9 ttyS19 ttyS3 urandom vcsa vcsu5
vport2p1
bsg dri kvm net shm tty12 tty23
tty34 tty45 tty56 ttyS0 ttyS2 ttyS30 usbmon0 vcsa1 vcsu6
vsock
btrfs-control fd liveupdate null snapshot tty13 tty24
tty35 tty46 tty57 ttyS1 ttyS20 ttyS31 usbmon1 vcsa2 vda
watchdog
bus full log nvram snd tty14 tty25
tty36 tty47 tty58 ttyS10 ttyS21 ttyS4 usbmon2 vcsa3 vda1
watchdog0
cdrom fuse loop-control port sr0 tty15 tty26
tty37 tty48 tty59 ttyS11 ttyS22 ttyS5 userfaultfd vcsa4 vda2
zero
char hidraw0 lp0 ppp stderr tty16 tty27
tty38 tty49 tty6 ttyS12 ttyS23 ttyS6 vcs vcsa5 vda3 zram0
console hpet lp1 ptmx stdin tty17 tty28
tty39 tty5 tty60 ttyS13 ttyS24 ttyS7 vcs1 vcsa6 vfio
core hugepages lp2 pts stdout tty18 tty29
tty4 tty50 tty61 ttyS14 ttyS25 ttyS8 vcs2 vcsu vga_arbiter
cpu hwrng lp3 random tty tty19 tty3
tty40 tty51 tty62 ttyS15 ttyS26 ttyS9 vcs3 vcsu1 vhci
cpu_dma_latency i2c-0 mapper rfkill tty0 tty2 tty30
tty41 tty52 tty63 ttyS16 ttyS27 udmabuf vcs4 vcsu2 vhost-net
cuse input mcelog rtc tty1 tty20 tty31
tty42 tty53 tty7 ttyS17 ttyS28 uhid vcs5 vcsu3 vhost-vsock
# tools/testing/selftests/vfio/scripts/setup.sh 0000:00:08.0
+ echo "vfio-pci" > /sys/bus/pci/devices/0000:00:08.0/driver_override
+ echo "0000:00:08.0" > /sys/bus/pci/drivers/vfio-pci/bind
tools/testing/selftests/vfio/scripts/lib.sh: line 9: echo: write error:
Invalid argument <--- the error is here.
# lspci -vvv -s 0000:00:08.0
00:08.0 Unclassified device [00ff]: Red Hat, Inc. QEMU PCI Test Device
Subsystem: Red Hat, Inc. QEMU Virtual Machine
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-
Region 0: Memory at fea1f000 (32-bit, non-prefetchable) [size=4K]
Region 1: I/O ports at c000 [size=256]
Hi, Vipin
I worked with QEMU PCI Test Device. But the following error occur.
"tools/testing/selftests/vfio/scripts/lib.sh: line 9: echo: write error:
Invalid argument"
Is this a known problem?
Thanks
Yanjun.Zhu
$ kexec ... # NOTE: Exact method will be distro-dependent
$ tools/testing/selftests/vfio/scripts/setup.sh 0000:00:04.0
$ tools/testing/selftests/vfio/vfio_pci_liveupdate_kexec_test --stage 2
0000:00:04.0
The second call to setup.sh is necessary because preserved devices are
not bound to a driver after Live Update. Such devices must be manually
bound by userspace after Live Update via driver_override.
This test is considered passing if all commands exit with 0.
Co-developed-by: David Matlack <[email protected]>
Signed-off-by: David Matlack <[email protected]>
Signed-off-by: Vipin Sharma <[email protected]>
---
tools/testing/selftests/vfio/Makefile | 4 +
.../vfio/vfio_pci_liveupdate_kexec_test.c | 89 +++++++++++++++++++
2 files changed, 93 insertions(+)
create mode 100644
tools/testing/selftests/vfio/vfio_pci_liveupdate_kexec_test.c
diff --git a/tools/testing/selftests/vfio/Makefile
b/tools/testing/selftests/vfio/Makefile
index 591f1a52c310..a2f0a459e1f4 100644
--- a/tools/testing/selftests/vfio/Makefile
+++ b/tools/testing/selftests/vfio/Makefile
@@ -15,6 +15,10 @@ TEST_GEN_PROGS += vfio_pci_driver_test
TEST_GEN_PROGS += vfio_pci_sriov_uapi_test
TEST_GEN_PROGS += vfio_pci_liveupdate_uapi_test
+# This test must be run manually since it requires the user/automation to
+# perform a kexec during the test.
+TEST_GEN_PROGS_EXTENDED += vfio_pci_liveupdate_kexec_test
+
TEST_FILES += scripts/cleanup.sh
TEST_FILES += scripts/lib.sh
TEST_FILES += scripts/run.sh
diff --git a/tools/testing/selftests/vfio/vfio_pci_liveupdate_kexec_test.c
b/tools/testing/selftests/vfio/vfio_pci_liveupdate_kexec_test.c
new file mode 100644
index 000000000000..15b3e3af91d1
--- /dev/null
+++ b/tools/testing/selftests/vfio/vfio_pci_liveupdate_kexec_test.c
@@ -0,0 +1,89 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <libliveupdate.h>
+#include <libvfio.h>
+
+static const char *device_bdf;
+
+static char state_session[LIVEUPDATE_SESSION_NAME_LENGTH];
+static char device_session[LIVEUPDATE_SESSION_NAME_LENGTH];
+
+enum {
+ STATE_TOKEN,
+ DEVICE_TOKEN,
+};
+
+static void before_kexec(int luo_fd)
+{
+ struct vfio_pci_device *device;
+ struct iommu *iommu;
+ int session_fd;
+ int ret;
+
+ iommu = iommu_init("iommufd");
+ device = vfio_pci_device_init(device_bdf, iommu);
+
+ create_state_file(luo_fd, state_session, STATE_TOKEN, /*next_stage=*/2);
+
+ session_fd = luo_create_session(luo_fd, device_session);
+ VFIO_ASSERT_GE(session_fd, 0);
+
+ printf("Preserving device in session\n");
+ ret = luo_session_preserve_fd(session_fd, device->fd, DEVICE_TOKEN);
+ VFIO_ASSERT_EQ(ret, 0);
+
+ close(luo_fd);
+ daemonize_and_wait();
+}
+
+static void after_kexec(int luo_fd, int state_session_fd)
+{
+ struct vfio_pci_device *device;
+ struct iommu *iommu;
+ int session_fd;
+ int device_fd;
+ int stage;
+
+ restore_and_read_stage(state_session_fd, STATE_TOKEN, &stage);
+ VFIO_ASSERT_EQ(stage, 2);
+
+ session_fd = luo_retrieve_session(luo_fd, device_session);
+ VFIO_ASSERT_GE(session_fd, 0);
+
+ printf("Finishing the session before retrieving the device (should
fail)\n");
+ VFIO_ASSERT_NE(luo_session_finish(session_fd), 0);
+
+ printf("Retrieving the device FD from LUO\n");
+ device_fd = luo_session_retrieve_fd(session_fd, DEVICE_TOKEN);
+ VFIO_ASSERT_GE(device_fd, 0);
+
+ printf("Finishing the session before binding to iommufd (should
fail)\n");
+ VFIO_ASSERT_NE(luo_session_finish(session_fd), 0);
+
+ printf("Binding the device to an iommufd and setting it up\n");
+ iommu = iommu_init("iommufd");
+
+ /*
+ * This will invoke various ioctls on device_fd such as
+ * VFIO_DEVICE_GET_INFO. So this is a decent sanity test
+ * that LUO actually handed us back a valid VFIO device
+ * file and not something else.
+ */
+ device = __vfio_pci_device_init(device_bdf, iommu, device_fd);
+
+ printf("Finishing the session\n");
+ VFIO_ASSERT_EQ(luo_session_finish(session_fd), 0);
+
+ vfio_pci_device_cleanup(device);
+ iommu_cleanup(iommu);
+}
+
+int main(int argc, char *argv[])
+{
+ device_bdf = vfio_selftests_get_bdf(&argc, argv);
+
+ sprintf(device_session, "device-%s", device_bdf);
+ sprintf(state_session, "state-%s", device_bdf);
+
+ return luo_test(argc, argv, state_session, before_kexec, after_kexec);
+}
--
Best Regards,
Yanjun.Zhu
