Fixes a bug whereby ‘processes’ would include kernel threads, thereby
leading the ‘stop’ method of ‘user-processes’ to wait indefinitely for a
kernel thread. Code taken from the Shepherd.
Fixes <https://issues.guix.gnu.org/68800>.
* guix/build/syscalls.scm (kernel?): Remove.
(linux-process-flags, linux-kernel-thread?, pseudo-process?): New
procedures.
(PF_KTHREAD): New variable.
(processes): Use ‘pseudo-process?’ instead of ‘kernel?’.
Reported-by: Tomas Volf <~@wolfsden.cz>
Change-Id: I8c439cdaf868a8f899de7fe500ce8bf10e5fc290