(In reply to Daniel P. Berrange from comment #3) > (In reply to Ahzo from comment #2) > > To check for the availability of the syscall, one can try it in a child > > process and see if the child is terminated by a signal, e.g. like this: > > Afraid not, QEMU's seccomp filter blocks use of fork() too :-)
Maybe it should, at least when using the spawn=deny option, but currently it doesn't. That option only blocks the fork, vfork and execve syscalls, but glibc's fork() function uses the clone syscall, and thus continues to work. However, that behavior might be different when using other C library implementations, so it wouldn't be correct to rely on this. One could use clone() instead of fork(), but future versions of qemu might block the clone syscall, as well. Unfortunately, I'm not aware of a proper solution for this bug short of adding a new API to the kernel. -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1815889 Title: qemu-system-x86_64 crashed with signal 31 in __pthread_setaffinity_new() Status in Mesa: Confirmed Status in QEMU: New Status in mesa package in Ubuntu: New Status in qemu package in Ubuntu: Triaged Bug description: Unable to launch Default Fedora 29 images in gnome-boxes ProblemType: Crash DistroRelease: Ubuntu 19.04 Package: qemu-system-x86 1:3.1+dfsg-2ubuntu1 ProcVersionSignature: Ubuntu 4.19.0-12.13-generic 4.19.18 Uname: Linux 4.19.0-12-generic x86_64 ApportVersion: 2.20.10-0ubuntu20 Architecture: amd64 Date: Thu Feb 14 11:00:45 2019 ExecutablePath: /usr/bin/qemu-system-x86_64 KvmCmdLine: COMMAND STAT EUID RUID PID PPID %CPU COMMAND MachineType: Dell Inc. Precision T3610 ProcEnviron: PATH=(custom, user) ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.19.0-12-generic root=UUID=939b509b-d627-4642-a655-979b44972d17 ro splash quiet vt.handoff=1 Signal: 31 SourcePackage: qemu StacktraceTop: __pthread_setaffinity_new (th=<optimized out>, cpusetsize=128, cpuset=0x7f5771fbf680) at ../sysdeps/unix/sysv/linux/pthread_setaffinity.c:34 () at /usr/lib/x86_64-linux-gnu/dri/radeonsi_dri.so () at /usr/lib/x86_64-linux-gnu/dri/radeonsi_dri.so start_thread (arg=<optimized out>) at pthread_create.c:486 clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95 Title: qemu-system-x86_64 crashed with signal 31 in __pthread_setaffinity_new() UpgradeStatus: Upgraded to disco on 2018-11-14 (91 days ago) UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo video dmi.bios.date: 11/14/2018 dmi.bios.vendor: Dell Inc. dmi.bios.version: A18 dmi.board.name: 09M8Y8 dmi.board.vendor: Dell Inc. dmi.board.version: A01 dmi.chassis.type: 7 dmi.chassis.vendor: Dell Inc. dmi.modalias: dmi:bvnDellInc.:bvrA18:bd11/14/2018:svnDellInc.:pnPrecisionT3610:pvr00:rvnDellInc.:rn09M8Y8:rvrA01:cvnDellInc.:ct7:cvr: dmi.product.name: Precision T3610 dmi.product.sku: 05D2 dmi.product.version: 00 dmi.sys.vendor: Dell Inc. To manage notifications about this bug go to: https://bugs.launchpad.net/mesa/+bug/1815889/+subscriptions
