On 14/06/17 10:19, Marc Gonzalez wrote: > On 14/06/2017 11:00, Marc Gonzalez wrote: > >> The MSI controller in Tango supports 256 message-signaled interrupts, >> and a single doorbell address. >> >> Signed-off-by: Marc Gonzalez <marc_gonzalez@xxxxxxxxxxxxxxxx> >> --- >> Changes from v6 to v7 >> o Call spin_lock() not spin_lock_irqsave() in the ISR >> --- >> drivers/pci/host/pcie-tango.c | 225 ++++++++++++++++++++++++++++++++++++++++++ >> 1 file changed, 225 insertions(+) > > Someone on IRC suggested testing the driver with LOCKDEP. > > If I understand the warning below correctly, I am not supposed > to call irq_domain_set_info() while holding used_msi_lock? Indeed. This creates an AB/BA situation, which will eventually deadlock. Once again, lockdep saves the day. > NB: in probe, my driver calls > > add_taint(TAINT_FIRMWARE_WORKAROUND, LOCKDEP_STILL_OK); > > This should not break LOCKDEP analysis, right? It doesn't. The code is provably wrong, and lockdep proved that it is wrong. M. -- Jazz is not dead. It just smells funny...
