Bug 841176
| Summary: | cpu_set a new cpu online will cause QEMU core dump | ||
|---|---|---|---|
| Product: | Red Hat Enterprise Linux 7 | Reporter: | Sibiao Luo <sluo> |
| Component: | qemu-kvm | Assignee: | Igor Mammedov <imammedo> |
| Status: | CLOSED WONTFIX | QA Contact: | Virtualization Bugs <virt-bugs> |
| Severity: | unspecified | Docs Contact: | |
| Priority: | unspecified | ||
| Version: | 7.0 | CC: | chayang, juzhang, knoel, michen, qzhang, shu, xfu |
| Target Milestone: | rc | ||
| Target Release: | --- | ||
| Hardware: | x86_64 | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | Bug Fix | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2012-08-01 10:08:19 UTC | Type: | Bug |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
upstream qemu (not qemu-kvm) doesn't/won't have cpu_set command and upstream qemu-kvm hotplug is known to be broken. My understanding is that rhel7 qemu will be based on upstream qemu (qemu-kvm) so all effort is directed there now and rhel7 should inherit CPU hotlug from there. Interface to add/remove vCPU is not defined yet for sure, it might be device_add/del. |
Description of problem: boot a rhel7 guest with "-smp 2,sockets=2,cores=1,threads=1,maxcpus=6", check the infos for each CPU after it boot up successfully, and then cpu_set a new cpu online via HMP monitor, QEMU core dump will occur. Version-Release number of selected component (if applicable): host info: # uname -r && rpm -q qemu-kvm 3.3.0-0.20.el7.x86_64 qemu-kvm-1.0-17.1.el7.x86_64 guest info: RHEL-7.0-x86_64 How reproducible: 100% Steps to Reproduce: 1.boot rhel7 guest with "-smp 2,sockets=2,cores=1,threads=1,maxcpus=6". eg:# /usr/bin/qemu-kvm -enable-kvm -smp 2,sockets=2,cores=1,threads=1,maxcpus=6 -m 2G -usb -device usb-tablet,id=input0 -name sluo-test -drive file=/home/RHEL-7.0-20120521.n.2_x86_64.qcow2,if=none,id=drive-virtio-disk-0,format=qcow2,cache=none,werror=stop,rerror=stop -device virtio-blk-pci,drive=drive-virtio-disk-0,id=virtio0,bootindex=1 -netdev tap,script=/etc/qemu-ifup,id=netdev0 -device virtio-net-pci,netdev=netdev0,id=device-net0 -vnc :1 -monitor stdio -boot menu=on 2.check the infos for each CPU. (qemu) info cpus * CPU #0: pc=0x00000000000fefc6 (halted) thread_id=24624 CPU #1: pc=0x00000000000ff0a2 (halted) thread_id=24626 3.cpu_set a new cpu online. (qemu) cpu_set 2 online Actual results: after the step 3, the QEMU core dump. (qemu) cpu_set 2 online qemu-kvm: /builddir/build/BUILD/qemu-kvm-1.0/hw/qdev.c:96: qdev_create_from_info: Assertion `bus->allow_hotplug' failed. Program received signal SIGABRT, Aborted. 0x00007ffff2fcf965 in raise () from /lib64/libc.so.6 (gdb) bt #0 0x00007ffff2fcf965 in raise () from /lib64/libc.so.6 #1 0x00007ffff2fd1118 in abort () from /lib64/libc.so.6 #2 0x00007ffff2fc86e2 in __assert_fail_base () from /lib64/libc.so.6 #3 0x00007ffff2fc8792 in __assert_fail () from /lib64/libc.so.6 #4 0x000055555569eca5 in qdev_create_from_info (bus=0x55555649a180, info=0x555555b8f300) at /usr/src/debug/qemu-kvm-1.0/hw/qdev.c:96 #5 0x000055555569fc39 in qdev_create (bus=bus@entry=0x0, name=name@entry=0x55555582babe "apic") at /usr/src/debug/qemu-kvm-1.0/hw/qdev.c:112 #6 0x0000555555782d72 in apic_init (apic_id=2 '\002', env=0x555556e1fcc0) at /usr/src/debug/qemu-kvm-1.0/hw/pc.c:886 #7 pc_new_cpu (cpu_model=<optimized out>) at /usr/src/debug/qemu-kvm-1.0/hw/pc.c:952 #8 0x00005555556f6937 in qemu_system_cpu_hot_add (cpu=2, state=<optimized out>) at /usr/src/debug/qemu-kvm-1.0/hw/acpi_piix4.c:592 #9 0x0000555555759779 in handle_user_command (mon=mon@entry=0x55555652ca20, cmdline=<optimized out>) at /usr/src/debug/qemu-kvm-1.0/monitor.c:4161 #10 0x0000555555759a9e in monitor_command_cb (mon=0x55555652ca20, cmdline=<optimized out>, opaque=<optimized out>) at /usr/src/debug/qemu-kvm-1.0/monitor.c:4777 #11 0x00005555556b138b in readline_handle_byte (rs=0x55555652ce90, ch=<optimized out>) at readline.c:370 #12 0x0000555555759847 in monitor_read (opaque=<optimized out>, buf=<optimized out>, size=<optimized out>) at /usr/src/debug/qemu-kvm-1.0/monitor.c:4763 #13 0x00005555556a3aba in qemu_chr_be_write (len=<optimized out>, buf=0x7fffffffcc70 "\r", s=0x5555563b37d0) at qemu-char.c:179 #14 fd_chr_read (opaque=0x5555563b37d0) at qemu-char.c:673 #15 0x000055555561d677 in qemu_iohandler_poll (readfds=readfds@entry=0x7fffffffdd20, writefds=writefds@entry=0x7fffffffdda0, xfds=xfds@entry=0x7fffffffde20, ret=ret@entry=1) at iohandler.c:156 #16 0x0000555555686961 in main_loop_wait (nonblocking=<optimized out>) at main-loop.c:463 #17 0x00005555555c8e49 in main_loop () at /usr/src/debug/qemu-kvm-1.0/vl.c:1482 #18 main (argc=<optimized out>, argv=<optimized out>, envp=<optimized out>) at /usr/src/debug/qemu-kvm-1.0/vl.c:3528 (gdb) q Expected results: should cpu_set a new cpu online successfully without any problem and the guest can work well. Additional info: BTW, I also have tried the latest qemu-kvm version '1.1.50 (qemu-kvm-devel)' from upstream, still hit this issue.