Bug 1984721
| Summary: | Unclear error message while hotplugging the same chardev | |||
|---|---|---|---|---|
| Product: | Red Hat Enterprise Linux 8 | Reporter: | liunana <nanliu> | |
| Component: | qemu-kvm | Assignee: | Marc-Andre Lureau <marcandre.lureau> | |
| qemu-kvm sub component: | General | QA Contact: | liunana <nanliu> | |
| Status: | CLOSED ERRATA | Docs Contact: | ||
| Severity: | medium | |||
| Priority: | medium | CC: | chayang, ddepaula, jinzhao, juzhang, marcandre.lureau, mdeng, virt-maint, yfu | |
| Version: | 8.5 | Keywords: | Regression, Triaged | |
| Target Milestone: | rc | |||
| Target Release: | 8.6 | |||
| Hardware: | x86_64 | |||
| OS: | Linux | |||
| Whiteboard: | ||||
| Fixed In Version: | qemu-kvm-6.1.0-2.module+el8.6.0+12861+13975d62 | Doc Type: | If docs needed, set a value | |
| Doc Text: | Story Points: | --- | ||
| Clone Of: | ||||
| : | 2001316 (view as bug list) | Environment: | ||
| Last Closed: | 2022-05-10 13:20:14 UTC | Type: | --- | |
| Regression: | --- | Mount Type: | --- | |
| Documentation: | --- | CRM: | ||
| Verified Versions: | Category: | --- | ||
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | ||
| Cloudforms Team: | --- | Target Upstream Version: | ||
| Embargoed: | ||||
| Bug Depends On: | 1997410 | |||
| Bug Blocks: | 2001316 | |||
Slow train has no such issue:
qemu-kvm-4.2.0-53.module+el8.5.0+11673+72138537.x86_64
{"execute":"chardev-add","arguments":{"id":"char2","backend":{"type":"socket","data":{"addr":{"type":"unix", "data": {"path": "/home/mm"}}}}}}
{"return": {}}
{"execute":"chardev-add","arguments":{"id":"char2","backend":{"type":"socket","data":{"addr":{"type":"unix", "data": {"path": "/home/mm"}}}}}}
{"error": {"class": "GenericError", "desc": "attempt to add duplicate property 'char2' to object (type 'container')"}}
Would this be good enough?
{"error": {"class": "GenericError", "desc": "Failed to open chardev 'char2': duplicate yank instance"}}
> {"error": {"class": "GenericError", "desc": "attempt to add duplicate property 'char2' to object (type 'container')"}}
wasn't very friendly either..
(In reply to Marc-Andre Lureau from comment #2) > Would this be good enough? > > {"error": {"class": "GenericError", "desc": "Failed to open chardev 'char2': > duplicate yank instance"}} > Hi, It's good to contain the duplicate chardev id, thanks. But seems 'open chardev' is not a match error log for duplicate hotplugging the same chardev. How about: {"error": {"class": "GenericError", "desc": "Failed to add chardev 'char2': duplicate yank instance"}} Besides, would you please help to explain more about what's the 'yank' function in the error log? Thanks. > > > {"error": {"class": "GenericError", "desc": "attempt to add duplicate property 'char2' to object (type 'container')"}} > > wasn't very friendly either. Seems clearer than "duplicate yank instance". Best regards Liu Nana Moving this to 8.6, in POST, and setting DTM=5 since this can be tested/validated using the weekly rebase as the fix has gone into qemu-6.1. Decision was to not backport for AV 8.5 since it's really an error path for newer code (yank functionality) that isn't necessarily reachable via libvirt or other means at this point. Neither RHV nor OSP will use 8.5. Move to RHEL since RHEL-AV will only be a rebuild of RHEL starting w/ 8.6.0 Added the RHEL rebase bz to depends on list Set 'Verified:Tested,SanityOnly' as gating test with qemu-kvm-6.1.0-2.module+el8.6.0+12861+13975d62 pass. Verified this bug with qemu-kvm-6.1.0-2.module+el8.6.0+12861+13975d62.
1. Boot qemu with cmdline:
/usr/libexec/qemu-kvm -monitor stdio -qmp tcp:0:4445,server=on,wait=off
2. Hotplug the same chardev, we can get the clear error log.
{"execute":"chardev-add","arguments":{"id":"char2","backend":{"type":"socket","data":{"addr":{"type":"unix", "data": {"path": "/home/mm"}}}}}}
{"return": {}}
{"execute":"chardev-add","arguments":{"id":"char2","backend":{"type":"socket","data":{"addr":{"type":"unix", "data": {"path": "/home/mm"}}}}}}
{"error": {"class": "GenericError", "desc": "Chardev with id 'char2' already exists"}}
Test Env:
4.18.0-345.1.el8.x86_64
qemu-kvm-6.1.0-2.module+el8.6.0+12861+13975d62.x86_64
I will move this bug to verified now, thanks.
Besides, seems two chardev backends can use the same path, is that normal?
# /usr/libexec/qemu-kvm -monitor stdio -qmp tcp:0:4445,server=on,wait=off -chardev socket,id=t1,path=/tmp/mm,server=on,wait=off -chardev socket,id=t2,path=/tmp/mm,server=on,wait=off
QEMU 6.1.0 monitor - type 'help' for more information
(qemu) VNC server running on ::1:5900
info chardev
t2: filename=disconnected:unix:/tmp/mm,server=on
t1: filename=disconnected:unix:/tmp/mm,server=on
compat_monitor1: filename=disconnected:tcp:0.0.0.0:4445,server=on
Would you please help to check this? Thanks!
Best regards
Liu Nana
(In reply to liunana from comment #9) > I will move this bug to verified now, thanks. > thanks > Besides, seems two chardev backends can use the same path, is that normal? > > # /usr/libexec/qemu-kvm -monitor stdio -qmp tcp:0:4445,server=on,wait=off > -chardev socket,id=t1,path=/tmp/mm,server=on,wait=off -chardev > socket,id=t2,path=/tmp/mm,server=on,wait=off > QEMU 6.1.0 monitor - type 'help' for more information > (qemu) VNC server running on ::1:5900 > info chardev > t2: filename=disconnected:unix:/tmp/mm,server=on > t1: filename=disconnected:unix:/tmp/mm,server=on > compat_monitor1: filename=disconnected:tcp:0.0.0.0:4445,server=on > > > Would you please help to check this? Thanks! > This expected, qemu has always unlink() the previous path before serving on unix socket. (in general, UNIX paths aren't very robust, management applications should use different sockets) 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 (Moderate: virt:rhel and virt-devel:rhel security, 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/RHSA-2022:1759 |
Description of problem: unclear error message while hotplugging the same chardev Version-Release number of selected component (if applicable): Host: kernel-4.18.0-323.el8.x86_64 qemu-kvm-6.0.0-24.module+el8.5.0+11844+1e3017bd.x86_64 How reproducible: 100% Steps to Reproduce: 1. Boot qemu with cmdline: /usr/libexec/qemu-kvm -monitor stdio -qmp tcp:0:4445,server=on,wait=off 2. Hotplug chardev: {"execute":"chardev-add","arguments":{"id":"char2","backend":{"type":"socket","data":{"addr":{"type":"unix", "data": {"path": "/home/mm"}}}}}} {"return": {}} 3. Hotplug the same chardev again: {"execute":"chardev-add","arguments":{"id":"char2","backend":{"type":"socket","data":{"addr":{"type":"unix", "data": {"path": "/home/mm"}}}}}} {"error": {"class": "GenericError", "desc": "duplicate yank instance"}} Actual results: Can't tell what's the reason that cause the failure of hotplugging. Expected results: We should have reported that the "id" value for the two chardevs is clashing. Additional info: