Subject: cpumask: Disable CONFIG_CPUMASK_OFFSTACK for RT From: Thomas Gleixner Date: Wed, 14 Dec 2011 01:03:49 +0100 We can't deal with the cpumask allocations which happen in atomic context (see arch/x86/kernel/apic/io_apic.c) on RT right now. Signed-off-by: Thomas Gleixner --- arch/x86/Kconfig | 2 +- lib/Kconfig | 1 + 2 files changed, 2 insertions(+), 1 deletion(-) Index: linux-stable/arch/x86/Kconfig =================================================================== --- linux-stable.orig/arch/x86/Kconfig +++ linux-stable/arch/x86/Kconfig @@ -757,7 +757,7 @@ config IOMMU_HELPER config MAXSMP bool "Enable Maximum number of SMP Processors and NUMA Nodes" depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL - select CPUMASK_OFFSTACK + select CPUMASK_OFFSTACK if !PREEMPT_RT_FULL ---help--- Enable maximum number of CPUS and NUMA Nodes for this architecture. If unsure, say N. Index: linux-stable/lib/Kconfig =================================================================== --- linux-stable.orig/lib/Kconfig +++ linux-stable/lib/Kconfig @@ -312,6 +312,7 @@ config CHECK_SIGNATURE config CPUMASK_OFFSTACK bool "Force CPU masks off stack" if DEBUG_PER_CPU_MAPS + depends on !PREEMPT_RT_FULL help Use dynamic allocation for cpumask_var_t, instead of putting them on the stack. This is a bit more expensive, but avoids