Bug 2150760

Crash occurs in :

#0  __strrchr_evex () at ../sysdeps/x86_64/multiarch/strrchr-evex.S:85
#1  0x00007fd8d10e0a55 in virFileIsSharedFSType (path=0x0, fstypes=2047) at ../src/util/virfile.c:3435
#2  0x00007fd8c015e2c3 in qemuTPMHasSharedStorage (def=<optimized out>) at ../src/qemu/qemu_tpm.c:1030
#3  0x00007fd8c01108ec in qemuMigrationSrcIsAllowed
#4  0x00007fd8c00d5263 in qemuDomainSaveInternal
#5  0x00007fd8c00d5cb8 in qemuDomainSaveFlags (dom=0x7fd8680a7f80, path=0x7fd8a40024b0 "/root/test.save", dxml=0x0, flags=0)
#6  0x00007fd8d12dca98 in virDomainSave (domain=domain@entry=0x7fd8680a7f80, to=<optimized out>) at ../src/libvirt-domain.c:896


Looks like we don't serialize 'tpm->data.emulator.storagepath' in the status XML thus a restart clears it. Same thing should happen on migration after restart of the daemon.

Another test scenario which have the similar crash:

Description of problem:
Dump guest failed with bzip2_format_dump

Version-Release number of selected component (if applicable):
libvirt-8.10.0-1.el9.x86_64
qemu-kvm-7.1.0-6.el9.x86_64

How reproducible:
100%

Steps to Reproduce:
1. Start a guest.
# virsh domstate avocado-vt-vm1
running

2. Edit the dump_image_format in qemu.cfg.
# vim /etc/libvirt/qemu.conf
......
dump_image_format = "bzip2"
......

3. Restart the virtqemud service.
# systemctl restart virtqemud

4. Dump the guest.
# virsh dump avocado-vt-vm1 /var/tmp/vm.core 
error: error: Failed to core dump domain 'avocado-vt-vm1' to /var/tmp/vm.core
Disconnected from qemu:///system due to end of file

Actual results:
Failed as step 4.

Expected results:
Should dump successfully.

Additional info:
1) It will not fail if we edit the qemu.conf first and then start the guest.
2) Log:
#0  0x00007fa8c983c528 in __strrchr_sse2 () from /lib64/libc.so.6
[Current thread is 1 (Thread 0x7fa8c69fc640 (LWP 140571))]
(gdb) bt
#0  0x00007fa8c983c528 in __strrchr_sse2 () from /lib64/libc.so.6
#1  0x00007fa8c9ee0a55 in virFileIsSharedFSType (path=0x0, fstypes=2047)
    at ../src/util/virfile.c:3435
#2  0x00007fa8c415a2c3 in qemuTPMHasSharedStorage (def=<optimized out>)
    at ../src/qemu/qemu_tpm.c:1030
#3  0x00007fa8c410c8ec in qemuMigrationSrcIsAllowed (driver=0x7fa87c0231e0, 
    vm=0x7fa87c096850, remote=<optimized out>, asyncJob=<optimized out>, 
    flags=<optimized out>) at ../src/qemu/qemu_migration.c:1559
#4  0x00007fa8c40d21f1 in doCoreDump (driver=0x7fa87c0231e0, vm=0x7fa87c096850, 
    path=0x7fa8a8001460 "/var/tmp/vm.core", dump_flags=<optimized out>, dumpformat=0)
    at ../src/qemu/qemu_driver.c:3135
#5  0x00007fa8c40d29e9 in qemuDomainCoreDumpWithFormat (dom=<optimized out>, 
    path=0x7fa8a8001460 "/var/tmp/vm.core", dumpformat=0, flags=0)
    at ../src/qemu/qemu_driver.c:3219
#6  0x00007fa8ca0df756 in virDomainCoreDump (domain=domain@entry=0x7fa87c01fee0, 
    to=<optimized out>, flags=0) at ../src/libvirt-domain.c:1427
#7  0x000055d36cd18fcc in remoteDispatchDomainCoreDump (server=0x55d36e4a7080, 
    msg=0x55d36e4af840, args=0x7fa8a8000b80, rerr=0x7fa8c69fb9a0, 
    client=<optimized out>) at src/remote/remote_daemon_dispatch_stubs.h:4894
#8  remoteDispatchDomainCoreDumpHelper (server=0x55d36e4a7080, 
--Type <RET> for more, q to quit, c to continue without paging--bt
    client=<optimized out>, msg=0x55d36e4af840, rerr=0x7fa8c69fb9a0, 
    args=0x7fa8a8000b80, ret=0x0) at src/remote/remote_daemon_dispatch_stubs.h:4873
#9  0x00007fa8c9ff112c in virNetServerProgramDispatchCall (msg=0x55d36e4af840, 
    client=0x55d36e4b50b0, server=0x55d36e4a7080, prog=0x55d36e4a8410)
    at ../src/rpc/virnetserverprogram.c:428
#10 virNetServerProgramDispatch (prog=0x55d36e4a8410, server=0x55d36e4a7080, 
    client=0x55d36e4b50b0, msg=0x55d36e4af840)
    at ../src/rpc/virnetserverprogram.c:302
#11 0x00007fa8c9ff6e78 in virNetServerProcessMsg (msg=<optimized out>, 
    prog=<optimized out>, client=<optimized out>, srv=0x55d36e4a7080)
    at ../src/rpc/virnetserver.c:135
#12 virNetServerHandleJob (jobOpaque=0x55d36e4a2750, opaque=0x55d36e4a7080)
    at ../src/rpc/virnetserver.c:155
#13 0x00007fa8c9f31cf3 in virThreadPoolWorker (opaque=<optimized out>)
    at ../src/util/virthreadpool.c:164
#14 0x00007fa8c9f312a9 in virThreadHelper (data=<optimized out>)
    at ../src/util/virthread.c:256
#15 0x00007fa8c989f802 in start_thread () from /lib64/libc.so.6
#16 0x00007fa8c983f450 in clone3 () from /lib64/libc.so.6

Patches proposed on the list:

https://listman.redhat.com/archives/libvir-list/2022-December/236084.html

Merged upstream as:

7a20341270 qemu: Init ext devices paths on reconnect
3458c3ff8c qemu_extdevice: Expose qemuExtDevicesInitPaths()
f1958a3e5e qemu_extdevice: Init paths in qemuExtDevicesPrepareDomain()
107ebe62f4 qemu_process: Document qemuProcessPrepare{Domain,Host}() order

v8.10.0-69-g7a20341270

Reproduce on:
libvirt-8.10.0-1.el9.x86_64
qemu-kvm-7.1.0-5.el9.x86_64

Steps:
# systemctl restart virtqemud

1.# virsh managedsave avocado-vt-vm1 
error: Disconnected from qemu:///system due to end of file
error: Failed to save domain 'avocado-vt-vm1' state
error: End of file while reading data: Input/output error

2.# virsh dump avocado-vt-vm1 avocado.dump
error: Disconnected from qemu:///system due to end of file
error: Failed to core dump domain 'avocado-vt-vm1' to avocado.dump
error: End of file while reading data: Input/output error

3.# virsh snapshot-create-as avocado-vt-vm1 sp1 --memspec file=/tmp/foo.image
error: Disconnected from qemu:///system due to end of file
error: End of file while reading data: Input/output error

4.# virsh migrate avocado-vt-vm1 --live qemu+ssh://hostB/system --verbose
error: Disconnected from qemu:///system due to end of file
error: End of file while reading data: Input/output error

Verify on:
libvirt-8.10.0-2.el9.x86_64

(# yum upgrade libvirt)

1.# systemctl restart virtqemud
# virsh managedsave avocado-vt-vm1 

Domain 'avocado-vt-vm1' state saved by libvirt

# virsh start avocado-vt-vm1 
Domain 'avocado-vt-vm1' started

2.# systemctl restart virtqemud
# virsh dump avocado-vt-vm1 vm.dump

Domain 'avocado-vt-vm1' dumped to vm.dump

3.# systemctl restart virtqemud
#  virsh snapshot-create-as avocado-vt-vm1 sp1 --memspec file=/tmp/foo.image
Domain snapshot sp1 created

# virsh snapshot-delete avocado-vt-vm1 sp1 --metadata
Domain snapshot sp1 deleted

4. # systemctl restart virtqemud
# virsh migrate avocado-vt-vm1 --live qemu+ssh://hostB/system --verbose
Migration: [100 %]

Verified per comment5.
And other regression tests for vtpm is pass:
https://libvirt-jenkins.rhev-ci-vms.eng.rdu2.redhat.com/job/libvirt-RHEL-9.2-runtest-x86_64-function-tpm_emulator/22/testReport/
libvirt	libvirt-8.10.0-2.el9.x86_64
qemu-kvm	qemu-kvm-7.1.0-6.el9.x86_64
kernel	kernel-5.14.0-205.el9.x86_64

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory (libvirt bug fix and enhancement update), and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHBA-2023:2171