On 2018-10-17 21:28, Emilio G. Cota wrote: > On Thu, Oct 11, 2018 at 20:25:08 +0100, Dr. David Alan Gilbert (git) wrote: >> From: Thomas Huth <[email protected]> >> >> We can re-use the s390-ccw bios code to implement a small firmware >> for a s390x guest which prints out the "A" and "B" characters and >> modifies the memory, as required for the migration test. >> >> [quintela: Converted the compile script to Makefile rules] >> Signed-off-by: Juan Quintela <[email protected]> >> Signed-off-by: Thomas Huth <[email protected]> >> Message-Id: <[email protected]> >> Reviewed-by: Philippe Mathieu-Daudé <[email protected]> >> Tested-by: Philippe Mathieu-Daudé <[email protected]> >> Signed-off-by: Dr. David Alan Gilbert <[email protected]> >> Fixed up Makefile since the aarch patch sneaked in first > > I suspect this test is giving me intermittent hangs. I've seen the hangs > in different machines, but when they're lightly loaded the > hang happens more frequently. > > To reproduce: > > $ ./configure --target-list=s390x-softmmu > $ make clean && make > $ for i in $(seq 0 150); do echo $i && make -j check-qtest || break; done > > It usually ends up hanging before 50 runs. When the hang happens, I see > two qemu-system-s390x processes with: > > -serial file:/tmp/migration-test-0FZErQ/dest_serial > > as an argument, among others. That means the migration test is the > one hanging, correct? > > Attaching with gdb just shows the TCG thread waiting for work > in qemu_tcg_rr_wait_io_event. > > Can anyone reproduce this? Otherwise, let me know what other info > I could provide.
I've finally been able to reproduce it - seems like it only happens here when the host is under heavy load. ... not sure whether I've got time to debug this before KVM forum, so if it bugs you, feel free to send a patch to disable the test in tests/Makefile.include for s390x again. Thomas
