From: Christoph Lameter Nasty problem with preemption on ia64 related to ia64_is_local_fpu_owner(): Keith Owens wrote: > > The entire fpu load/restore logic on ia64 needs reviewing > for preemption. There is an implicit assumption that the fpu state is > atomically saved and restored on the current cpu, while under the > control of psr->mfh. Preempt has the potential to migrate a task while > it is in the middle of save/restore fpu, breaking that assumption. > Other ia64 register save/restore code might have similar problems. > So let's disable ia64 preempt for 2.6.12. Signed-off-by: Andrew Morton --- arch/ia64/Kconfig | 2 +- 1 files changed, 1 insertion(+), 1 deletion(-) diff -puN arch/ia64/Kconfig~ia64-disable-preempt arch/ia64/Kconfig --- 25/arch/ia64/Kconfig~ia64-disable-preempt 2005-06-06 00:11:52.000000000 -0700 +++ 25-akpm/arch/ia64/Kconfig 2005-06-06 00:11:52.000000000 -0700 @@ -285,7 +285,7 @@ config SCHED_SMT overhead in some places. If unsure say N here. config PREEMPT - bool "Preemptible Kernel" + default n help This option reduces the latency of the kernel when reacting to real-time or interactive events by allowing a low priority process to _