This is a note to let you know that I've just added the patch titled arm64: Fix incorrect per-cpu usage for boot CPU to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: arm64-fix-incorrect-per-cpu-usage-for-boot-cpu.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 9113c2aa05e9848cd4f1154abee17d4f265f012d Mon Sep 17 00:00:00 2001 From: Suzuki K Poulose <suzuki.poulose@xxxxxxx> Date: Thu, 21 Jul 2016 11:12:55 +0100 Subject: arm64: Fix incorrect per-cpu usage for boot CPU From: Suzuki K Poulose <suzuki.poulose@xxxxxxx> commit 9113c2aa05e9848cd4f1154abee17d4f265f012d upstream. In smp_prepare_boot_cpu(), we invoke cpuinfo_store_boot_cpu to store the cpuinfo in a per-cpu ptr, before initialising the per-cpu offset for the boot CPU. This patch reorders the sequence to make sure we initialise the per-cpu offset before accessing the per-cpu area. Commit 4b998ff1885eec ("arm64: Delay cpuinfo_store_boot_cpu") fixed the issue where we modified the per-cpu area even before the kernel initialises the per-cpu areas, but failed to wait until the boot cpu updated it's offset. Fixes: 4b998ff1885e ("arm64: Delay cpuinfo_store_boot_cpu") Cc: <stable@xxxxxxxxxxxxxxx> # 4.4+ Cc: Will Deacon <will.deacon@xxxxxxx> Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx> Acked-by: Mark Rutland <mark.rutland@xxxxxxx> Signed-off-by: Catalin Marinas <catalin.marinas@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/arm64/kernel/smp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -333,8 +333,8 @@ void __init smp_cpus_done(unsigned int m void __init smp_prepare_boot_cpu(void) { - cpuinfo_store_boot_cpu(); set_my_cpu_offset(per_cpu_offset(smp_processor_id())); + cpuinfo_store_boot_cpu(); } static u64 __init of_get_cpu_mpidr(struct device_node *dn) Patches currently in stable-queue which might be from suzuki.poulose@xxxxxxx are queue-4.4/arm64-fix-incorrect-per-cpu-usage-for-boot-cpu.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html