freebsd-dev/sys/pc98
Attilio Rao be1057174e MFC r196196:
* Completely remove the option STOP_NMI from the kernel.  This option
  has proven to have a good effect when entering KDB by using a NMI,
  but it completely violates all the good rules about interrupts
  disabled while holding a spinlock in other occasions.  This can be the
  cause of deadlocks on events where a normal IPI_STOP is expected.
* Add an new IPI called IPI_STOP_HARD on all the supported architectures.
  This IPI is responsible for sending a stop message among CPUs using a
  privileged channel when disponible. In other cases it just does match a
  normal IPI_STOP.
  Right now the IPI_STOP_HARD functionality uses a NMI on ia32 and amd64
  architectures, while on the other has a normal IPI_STOP effect. It is
  responsibility of maintainers to eventually implement an hard stop
  when necessary and possible.
* Use the new IPI facility in order to implement a new userend SMP kernel
  function called stop_cpus_hard(). That is specular to stop_cpu() but
  it does use the privileged channel for the stopping facility.
* Let KDB use the newly introduced function stop_cpus_hard() and leave
  stop_cpus() for all the other cases
* Disable interrupts on CPU0 when starting the process of APs suspension.
* Style cleanup and comments adding

This patch should fix the reboot/shutdown deadlocks many users are
constantly reporting on mailing lists.

Please don't forget to update your config file with the STOP_NMI
option removal

Reviewed by:  jhb
Tested by:    pho, bz, rink
Approved by:  re (kib)
2009-08-13 17:54:11 +00:00
..
apm Rename from apm_bioscall.s to apm_bioscall.S for removing a special rule 2005-04-20 12:28:20 +00:00
cbus Make the newbus subsystem Giant free by adding the new newbus sxlock. 2009-08-02 14:28:40 +00:00
compile
conf MFC r196196: 2009-08-13 17:54:11 +00:00
include Add stub vm.h for pc98. 2009-06-27 02:20:31 +00:00
linux Add reach-over include files to read i386/foo.h. In time, the pc98 2005-04-01 23:19:43 +00:00
pc98 Implement a facility for dynamic per-cpu variables. 2009-06-23 22:42:39 +00:00