This is a note to let you know that I've just added the patch titled x86/microcode: Request microcode on the BSP to the 4.15-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: x86-microcode-request-microcode-on-the-bsp.patch and it can be found in the queue-4.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From cfb52a5a09c8ae3a1dafb44ce549fde5b69e8117 Mon Sep 17 00:00:00 2001 From: Borislav Petkov <bp@xxxxxxx> Date: Wed, 28 Feb 2018 11:28:45 +0100 Subject: x86/microcode: Request microcode on the BSP From: Borislav Petkov <bp@xxxxxxx> commit cfb52a5a09c8ae3a1dafb44ce549fde5b69e8117 upstream. ... so that any newer version can land in the cache and can later be fished out by the application functions. Do that before grabbing the hotplug lock. Signed-off-by: Borislav Petkov <bp@xxxxxxx> Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Tested-by: Tom Lendacky <thomas.lendacky@xxxxxxx> Tested-by: Ashok Raj <ashok.raj@xxxxxxxxx> Reviewed-by: Tom Lendacky <thomas.lendacky@xxxxxxx> Cc: Arjan Van De Ven <arjan.van.de.ven@xxxxxxxxx> Link: https://lkml.kernel.org/r/20180228102846.13447-7-bp@xxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/x86/kernel/cpu/microcode/core.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) --- a/arch/x86/kernel/cpu/microcode/core.c +++ b/arch/x86/kernel/cpu/microcode/core.c @@ -499,15 +499,10 @@ static int check_online_cpus(void) static enum ucode_state reload_for_cpu(int cpu) { struct ucode_cpu_info *uci = ucode_cpu_info + cpu; - enum ucode_state ustate; if (!uci->valid) return UCODE_OK; - ustate = microcode_ops->request_microcode_fw(cpu, µcode_pdev->dev, true); - if (ustate != UCODE_OK) - return ustate; - return apply_microcode_on_target(cpu); } @@ -515,11 +510,11 @@ static ssize_t reload_store(struct devic struct device_attribute *attr, const char *buf, size_t size) { + int cpu, bsp = boot_cpu_data.cpu_index; enum ucode_state tmp_ret = UCODE_OK; bool do_callback = false; unsigned long val; ssize_t ret = 0; - int cpu; ret = kstrtoul(buf, 0, &val); if (ret) @@ -528,6 +523,10 @@ static ssize_t reload_store(struct devic if (val != 1) return size; + tmp_ret = microcode_ops->request_microcode_fw(bsp, µcode_pdev->dev, true); + if (tmp_ret != UCODE_OK) + return size; + get_online_cpus(); ret = check_online_cpus(); Patches currently in stable-queue which might be from bp@xxxxxxx are queue-4.15/x86-microcode-intel-check-microcode-revision-before-updating-sibling-threads.patch queue-4.15/x86-microcode-attempt-late-loading-only-when-new-microcode-is-present.patch queue-4.15/x86-microcode-propagate-return-value-from-updating-functions.patch queue-4.15/x86-cpu-check-cpu-feature-bits-after-microcode-upgrade.patch queue-4.15/x86-microcode-intel-writeback-and-invalidate-caches-before-updating-microcode.patch queue-4.15/x86-microcode-intel-look-into-the-patch-cache-first.patch queue-4.15/edac-mv64x60-fix-an-error-handling-path.patch queue-4.15/x86-microcode-request-microcode-on-the-bsp.patch queue-4.15/x86-microcode-get-rid-of-struct-apply_microcode_ctx.patch queue-4.15/x86-microcode-fix-cpu-synchronization-routine.patch queue-4.15/x86-microcode-synchronize-late-microcode-loading.patch queue-4.15/x86-microcode-do-not-upload-microcode-if-cpus-are-offline.patch queue-4.15/x86-cpu-add-a-microcode-loader-callback.patch