powerpc: select CPUMASK_OFFSTACK if NR_CPUS >= 8192

Some core kernel code starts to go beyond the 2048 byte stack size
warning at NR_CPUS=8192, so select CPUMASK_OFFSTACK in that case.
x86 does similarly for very large NR_CPUS.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211105035042.1398309-2-npiggin@gmail.com

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index dea74d7..bb5e44e 100644 (file)
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -165,6 +165,7 @@ config PPC
        select BINFMT_ELF
        select BUILDTIME_TABLE_SORT
        select CLONE_BACKWARDS
+       select CPUMASK_OFFSTACK                 if NR_CPUS >= 8192
        select DCACHE_WORD_ACCESS               if PPC64 && CPU_LITTLE_ENDIAN
        select DMA_OPS_BYPASS                   if PPC64
        select DMA_OPS                          if PPC64