diff --git a/arch/arm/kernel/fiq.c b/arch/arm/kernel/fiq.c index fc7920288a3d90a3f9c3ca38be03ff845f84515a..918875d96d5dc598985c7dce050e0a1785637b49 100644 --- a/arch/arm/kernel/fiq.c +++ b/arch/arm/kernel/fiq.c @@ -89,7 +89,8 @@ void set_fiq_handler(void *start, unsigned int length) memcpy(base + offset, start, length); if (!cache_is_vipt_nonaliasing()) - flush_icache_range(base + offset, offset + length); + flush_icache_range((unsigned long)base + offset, offset + + length); flush_icache_range(0xffff0000 + offset, 0xffff0000 + offset + length); } diff --git a/arch/arm/kernel/machine_kexec.c b/arch/arm/kernel/machine_kexec.c index d7c82df692436df0248fa1a00502cf74b7fca23c..57221e349a7ce0eec03445cd56de2845e5d23358 100644 --- a/arch/arm/kernel/machine_kexec.c +++ b/arch/arm/kernel/machine_kexec.c @@ -82,6 +82,7 @@ void machine_crash_nonpanic_core(void *unused) crash_save_cpu(®s, smp_processor_id()); flush_cache_all(); + set_cpu_online(smp_processor_id(), false); atomic_dec(&waiting_for_crash_ipi); while (1) cpu_relax(); diff --git a/arch/arm/mm/Kconfig b/arch/arm/mm/Kconfig index db5c2cab8fda4251bb636aa5567afafe5cfdb406..cd2c88e7a8f7557bfe299a7a6b364c395a969428 100644 --- a/arch/arm/mm/Kconfig +++ b/arch/arm/mm/Kconfig @@ -809,15 +809,18 @@ config KUSER_HELPERS the CPU type fitted to the system. This permits binaries to be run on ARMv4 through to ARMv7 without modification. + See Documentation/arm/kernel_user_helpers.txt for details. + However, the fixed address nature of these helpers can be used by ROP (return orientated programming) authors when creating exploits. If all of the binaries and libraries which run on your platform are built specifically for your platform, and make no use of - these helpers, then you can turn this option off. However, - when such an binary or library is run, it will receive a SIGILL - signal, which will terminate the program. + these helpers, then you can turn this option off to hinder + such exploits. However, in that case, if a binary or library + relying on those helpers is run, it will receive a SIGILL signal, + which will terminate the program. Say N here only if you are absolutely certain that you do not need these helpers; otherwise, the safe option is to say Y.