firmware versions which wedge when using the OFW test service,
so given that we don't really depend on SUNW,stop-self just nuke
it altogether instead of risking problems.
- At least Fire V880 have a small hardware glitch which causes the
reception of IDR_NACKs for CPUs we actually haven't tried to send
an IPI to, even not as part of the initial try. According to tests
this apparently can be safely ignored though, so just return if
checking for the individual IDR_NACKs indicates no outstanding
dispatch. Serializing the sending of IPIs between MD and MI code
by the combined usage of smp_ipi_mtx makes no difference to this
phenomenon. [1]
- Provide relevant debugging bits already with the initial panic
in case of problems with the IPI dispatch, which would have
allowed to diagnose the above problem without a specially built
kernel.
- In case of cheetah_ipi_selected() base the delay we wait for
other CPUs which also might want to dispatch IPIs on the total
amount of CPUs instead of just the number of CPUs we let this
CPU send IPIs to because in the worst case all CPUs also want
to IPI us at the same time.
Reported and access for extensive tests provided by: Beat Gaetzi [1]
b477a2c916