Re: [RFC -v9 1/4] Add Kconfig option ARCH_HAVE_NMI_SAFE_CMPXCHG

David Miller
2010-12-23T17:35:19Z

From: Huang Ying <ying.huang@intel.com>
Date: Thu, 23 Dec 2010 13:43:20 +0800

> --- a/arch/sparc/Kconfig
> +++ b/arch/sparc/Kconfig
> @@ -22,6 +22,7 @@ config SPARC
> select RTC_CLASS
> select RTC_DRV_M48T59
> select HAVE_IRQ_WORK
> + select ARCH_HAVE_NMI_SAFE_CMPXCHG
> select HAVE_DMA_ATTRS
> select HAVE_DMA_API_DEBUG
> select HAVE_ARCH_JUMP_LABEL

This should only be set for "SPARC64". SPARC32's cmpxchg uses spinlocks and
IRQ disabling, which is not NMI safe.