From: Marc Zyngier Date: Fri, 18 Dec 2015 10:06:47 +0000 (+0100) Subject: ARM: 8488/1: Make IPI_CPU_BACKTRACE a "non-secure" SGI X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=e7273ff49acf;p=openwrt%2Fstaging%2Fblogic.git ARM: 8488/1: Make IPI_CPU_BACKTRACE a "non-secure" SGI Having IPI_CPU_BACKTRACE as SGI15 may not work if the kernel is running in non-secure mode and that the secure firmware has decided to follow ARM's recommendations that SGI8-15 should be reserved for secure purpose. Now that we are "only" using SGI0-6, change IPI_CPU_BACKTRACE to use SGI7, which makes it more likely to work. Signed-off-by: Marc Zyngier Signed-off-by: Russell King --- diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index d50a77d638d3..37312f6749f3 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -72,7 +72,12 @@ enum ipi_msg_type { IPI_CPU_STOP, IPI_IRQ_WORK, IPI_COMPLETION, - IPI_CPU_BACKTRACE = 15, + IPI_CPU_BACKTRACE, + /* + * SGI8-15 can be reserved by secure firmware, and thus may + * not be usable by the kernel. Please keep the above limited + * to at most 8 entries. + */ }; static DECLARE_COMPLETION(cpu_running);