I'm using Debian GNU/Linux on hppa, in a virtual machine emulated by QEMU 8.0.2. Kernel: Linux 6.3.0-2-parisc parisc
PA-RISC Linux kernels starting from 6.2 up until 6.7-rc1 have been lightly tested because I was mostly busy with enabling 64-bit hppa CPU support in qemu. On Debian we currently use kernel 6.1-stable series which works fine with your testcase: "/bin/echo `seq 913`". Starting with Linux kernel 6.7-rc2 the test works OK too, and there is a whole bunch of kernel patches (in 6.7-rc2) currently scheduled to be backported. I suggest you test again in 1-2 weeks (when the patches have been incorporated in the stable series kernels), or try a 6.1-stable or 6.7-rc2 kernel for now. Helge