user-level: 0.662
virtual: 0.632
permissions: 0.623
risc-v: 0.613
vnc: 0.611
device: 0.589
TCG: 0.589
register: 0.588
ppc: 0.570
architecture: 0.526
peripherals: 0.519
debug: 0.512
performance: 0.512
hypervisor: 0.507
assembly: 0.493
PID: 0.490
semantic: 0.490
graphic: 0.469
arm: 0.452
VMM: 0.449
KVM: 0.423
files: 0.408
mistranslation: 0.390
kernel: 0.372
socket: 0.367
boot: 0.360
x86: 0.346
network: 0.322
i386: 0.296

Qemu cmdline core dumped with more(8193 or more) cpus

---Debugger---
A debugger is not configured
 
---Steps to Reproduce---
 
---Problem Description---
 Qemu cmdline core dumped with more(8193 or more) cpus
 
---Debugger---
A debugger is not configured
 
---Steps to Reproduce---
 Qemu cmdline core dumped when more number of CPUs were given.


[root@ltcmihawk39 ~]# qemu-system-ppc64 -accel tcg -smp 10,maxcpus=9000
**
ERROR:../tcg/region.c:782:tcg_region_init: assertion failed: (region_size >= 2 * page_size)
Bail out! ERROR:../tcg/region.c:782:tcg_region_init: assertion failed: (region_size >= 2 * page_size)
Aborted (core dumped)

Expected Result:
Warning message like "Number of cpus requested exceeds the cpus supported"

Actual Result:
core dumped

Steps to Reproduce:
--------------------

1. Clone the upstream qemu from https://gitlab.com/qemu-project/qemu.git
2. Compile qemu with below steps.
    cd qemu/
    git submodule init
    git submodule update --recursive
    ./configure --target-list=ppc64-softmmu --prefix=/usr
    make
    make install
3. set maxcpus=8193 or more


[root@ltcmihawk39 ~]# qemu-system-ppc64 --version
QEMU emulator version 8.0.94 (v8.1.0-rc4)
Copyright (c) 2003-2023 Fabrice Bellard and the QEMU Project developers

NOTE: This behavior is observed only when qemu is built without disabling the tcg.
 
Contact Information = <email address hidden> 
 
Machine Type = x 
 
---uname output---
x

Action needed

Our IBM Dev want to include this patch in latest Canonical distro.

Need the distro to review and integrate fixes provided by IBM 

https://github.com/qemu/qemu/commit/c4f91d7b7be76c47015521ab0109c6e998a369b0

Need to include this commit in latest Canonical distro.

FWIW, this bug tracker is not used for qemu for a long time.  See https://gitlab.com/qemu-project/qemu/ instead.

Hi Michael,
as I read it this is just for tracking the integration of the patch which is already upstream to go into Ubuntu - in that case the tracker is correct.

But it was wrong in the beginning, yet Frank fixed it and your comments raced.

@Frank maybe some teaching needed to have bugproxy open it in the right place to begin with?


quilt patch for commit c4f91d7b7be

This bug was fixed in the package qemu - 1:8.2.1+ds-1ubuntu8

---------------
qemu (1:8.2.1+ds-1ubuntu8) noble; urgency=medium

  * d/p/u/lp2012763-maxcpus-too-low.patch: Actually set the max_cpus
    property of the new Mantic machine types. (LP: #2012763)

 -- Sergio Durigan Junior <email address hidden>  Mon, 25 Mar 2024 14:58:39 -0400

------- Comment From <email address hidden> 2024-04-18 11:45 EDT-------
I have verified this bug on latest Ubuntu24.04 Host and the issue is not getting reproduced anymore!

root@ubuntu2404lp2:~# qemu-system-ppc64 -accel tcg -smp 10,maxcpus=9000
qemu-system-ppc64: Invalid SMP CPUs 9000. The max CPUs supported by machine 'pseries-noble' is 4096

root@ubuntu2404lp2:~# qemu-system-ppc64 -accel tcg -smp 10,maxcpus=123456789
qemu-system-ppc64: Invalid SMP CPUs 123456789. The max CPUs supported by machine 'pseries-noble' is 4096

kernel: 6.8.0-22-generic ppc64le ppc64le GNU/Linux
qemu: QEMU emulator version 8.2.2 (Debian 1:8.2.2+ds-0ubuntu1)