4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Russell King rmk+kernel@armlinux.org.uk
Commit 26602161b5ba795928a5a719fe1d5d9f2ab5c3ef upstream.
Check for CPU bugs when secondary processors are being brought online, and also when CPUs are resuming from a low power mode. This gives an opportunity to check that processor specific bug workarounds are correctly enabled for all paths that a CPU re-enters the kernel.
Signed-off-by: Russell King rmk+kernel@armlinux.org.uk Reviewed-by: Florian Fainelli f.fainelli@gmail.com Boot-tested-by: Tony Lindgren tony@atomide.com Reviewed-by: Tony Lindgren tony@atomide.com Acked-by: Marc Zyngier marc.zyngier@arm.com Signed-off-by: David A. Long dave.long@linaro.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/arm/include/asm/bugs.h | 2 ++ arch/arm/kernel/bugs.c | 5 +++++ arch/arm/kernel/smp.c | 4 ++++ arch/arm/kernel/suspend.c | 2 ++ 4 files changed, 13 insertions(+)
--- a/arch/arm/include/asm/bugs.h +++ b/arch/arm/include/asm/bugs.h @@ -14,8 +14,10 @@ extern void check_writebuffer_bugs(void)
#ifdef CONFIG_MMU extern void check_bugs(void); +extern void check_other_bugs(void); #else #define check_bugs() do { } while (0) +#define check_other_bugs() do { } while (0) #endif
#endif --- a/arch/arm/kernel/bugs.c +++ b/arch/arm/kernel/bugs.c @@ -3,7 +3,12 @@ #include <asm/bugs.h> #include <asm/proc-fns.h>
+void check_other_bugs(void) +{ +} + void __init check_bugs(void) { check_writebuffer_bugs(); + check_other_bugs(); } --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -29,6 +29,7 @@ #include <linux/irq_work.h>
#include <linux/atomic.h> +#include <asm/bugs.h> #include <asm/smp.h> #include <asm/cacheflush.h> #include <asm/cpu.h> @@ -400,6 +401,9 @@ asmlinkage void secondary_start_kernel(v * before we continue - which happens after __cpu_up returns. */ set_cpu_online(cpu, true); + + check_other_bugs(); + complete(&cpu_running);
local_irq_enable(); --- a/arch/arm/kernel/suspend.c +++ b/arch/arm/kernel/suspend.c @@ -1,6 +1,7 @@ #include <linux/init.h> #include <linux/slab.h>
+#include <asm/bugs.h> #include <asm/cacheflush.h> #include <asm/idmap.h> #include <asm/pgalloc.h> @@ -34,6 +35,7 @@ int cpu_suspend(unsigned long arg, int ( cpu_switch_mm(mm->pgd, mm); local_flush_bp_all(); local_flush_tlb_all(); + check_other_bugs(); }
return ret;