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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /arch/x86/kernel/cpu/microcode/core.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip
Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
Diffstat (limited to 'arch/x86/kernel/cpu/microcode/core.c')
-rw-r--r--arch/x86/kernel/cpu/microcode/core.c680
1 files changed, 680 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/microcode/core.c b/arch/x86/kernel/cpu/microcode/core.c
new file mode 100644
index 000000000..7a329e561
--- /dev/null
+++ b/arch/x86/kernel/cpu/microcode/core.c
@@ -0,0 +1,680 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * CPU Microcode Update Driver for Linux
+ *
+ * Copyright (C) 2000-2006 Tigran Aivazian <aivazian.tigran@gmail.com>
+ * 2006 Shaohua Li <shaohua.li@intel.com>
+ * 2013-2016 Borislav Petkov <bp@alien8.de>
+ *
+ * X86 CPU microcode early update for Linux:
+ *
+ * Copyright (C) 2012 Fenghua Yu <fenghua.yu@intel.com>
+ * H Peter Anvin" <hpa@zytor.com>
+ * (C) 2015 Borislav Petkov <bp@alien8.de>
+ *
+ * This driver allows to upgrade microcode on x86 processors.
+ */
+
+#define pr_fmt(fmt) "microcode: " fmt
+
+#include <linux/platform_device.h>
+#include <linux/stop_machine.h>
+#include <linux/syscore_ops.h>
+#include <linux/miscdevice.h>
+#include <linux/capability.h>
+#include <linux/firmware.h>
+#include <linux/kernel.h>
+#include <linux/delay.h>
+#include <linux/mutex.h>
+#include <linux/cpu.h>
+#include <linux/nmi.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+
+#include <asm/microcode_intel.h>
+#include <asm/cpu_device_id.h>
+#include <asm/microcode_amd.h>
+#include <asm/perf_event.h>
+#include <asm/microcode.h>
+#include <asm/processor.h>
+#include <asm/cmdline.h>
+#include <asm/setup.h>
+
+#define DRIVER_VERSION "2.2"
+
+static struct microcode_ops *microcode_ops;
+static bool dis_ucode_ldr = true;
+
+bool initrd_gone;
+
+LIST_HEAD(microcode_cache);
+
+/*
+ * Synchronization.
+ *
+ * All non cpu-hotplug-callback call sites use:
+ *
+ * - microcode_mutex to synchronize with each other;
+ * - cpus_read_lock/unlock() to synchronize with
+ * the cpu-hotplug-callback call sites.
+ *
+ * We guarantee that only a single cpu is being
+ * updated at any particular moment of time.
+ */
+static DEFINE_MUTEX(microcode_mutex);
+
+struct ucode_cpu_info ucode_cpu_info[NR_CPUS];
+
+struct cpu_info_ctx {
+ struct cpu_signature *cpu_sig;
+ int err;
+};
+
+/*
+ * Those patch levels cannot be updated to newer ones and thus should be final.
+ */
+static u32 final_levels[] = {
+ 0x01000098,
+ 0x0100009f,
+ 0x010000af,
+ 0, /* T-101 terminator */
+};
+
+/*
+ * Check the current patch level on this CPU.
+ *
+ * Returns:
+ * - true: if update should stop
+ * - false: otherwise
+ */
+static bool amd_check_current_patch_level(void)
+{
+ u32 lvl, dummy, i;
+ u32 *levels;
+
+ native_rdmsr(MSR_AMD64_PATCH_LEVEL, lvl, dummy);
+
+ if (IS_ENABLED(CONFIG_X86_32))
+ levels = (u32 *)__pa_nodebug(&final_levels);
+ else
+ levels = final_levels;
+
+ for (i = 0; levels[i]; i++) {
+ if (lvl == levels[i])
+ return true;
+ }
+ return false;
+}
+
+static bool __init check_loader_disabled_bsp(void)
+{
+ static const char *__dis_opt_str = "dis_ucode_ldr";
+
+#ifdef CONFIG_X86_32
+ const char *cmdline = (const char *)__pa_nodebug(boot_command_line);
+ const char *option = (const char *)__pa_nodebug(__dis_opt_str);
+ bool *res = (bool *)__pa_nodebug(&dis_ucode_ldr);
+
+#else /* CONFIG_X86_64 */
+ const char *cmdline = boot_command_line;
+ const char *option = __dis_opt_str;
+ bool *res = &dis_ucode_ldr;
+#endif
+
+ /*
+ * CPUID(1).ECX[31]: reserved for hypervisor use. This is still not
+ * completely accurate as xen pv guests don't see that CPUID bit set but
+ * that's good enough as they don't land on the BSP path anyway.
+ */
+ if (native_cpuid_ecx(1) & BIT(31))
+ return *res;
+
+ if (x86_cpuid_vendor() == X86_VENDOR_AMD) {
+ if (amd_check_current_patch_level())
+ return *res;
+ }
+
+ if (cmdline_find_option_bool(cmdline, option) <= 0)
+ *res = false;
+
+ return *res;
+}
+
+void __init load_ucode_bsp(void)
+{
+ unsigned int cpuid_1_eax;
+ bool intel = true;
+
+ if (!have_cpuid_p())
+ return;
+
+ cpuid_1_eax = native_cpuid_eax(1);
+
+ switch (x86_cpuid_vendor()) {
+ case X86_VENDOR_INTEL:
+ if (x86_family(cpuid_1_eax) < 6)
+ return;
+ break;
+
+ case X86_VENDOR_AMD:
+ if (x86_family(cpuid_1_eax) < 0x10)
+ return;
+ intel = false;
+ break;
+
+ default:
+ return;
+ }
+
+ if (check_loader_disabled_bsp())
+ return;
+
+ if (intel)
+ load_ucode_intel_bsp();
+ else
+ load_ucode_amd_bsp(cpuid_1_eax);
+}
+
+static bool check_loader_disabled_ap(void)
+{
+#ifdef CONFIG_X86_32
+ return *((bool *)__pa_nodebug(&dis_ucode_ldr));
+#else
+ return dis_ucode_ldr;
+#endif
+}
+
+void load_ucode_ap(void)
+{
+ unsigned int cpuid_1_eax;
+
+ if (check_loader_disabled_ap())
+ return;
+
+ cpuid_1_eax = native_cpuid_eax(1);
+
+ switch (x86_cpuid_vendor()) {
+ case X86_VENDOR_INTEL:
+ if (x86_family(cpuid_1_eax) >= 6)
+ load_ucode_intel_ap();
+ break;
+ case X86_VENDOR_AMD:
+ if (x86_family(cpuid_1_eax) >= 0x10)
+ load_ucode_amd_ap(cpuid_1_eax);
+ break;
+ default:
+ break;
+ }
+}
+
+static int __init save_microcode_in_initrd(void)
+{
+ struct cpuinfo_x86 *c = &boot_cpu_data;
+ int ret = -EINVAL;
+
+ switch (c->x86_vendor) {
+ case X86_VENDOR_INTEL:
+ if (c->x86 >= 6)
+ ret = save_microcode_in_initrd_intel();
+ break;
+ case X86_VENDOR_AMD:
+ if (c->x86 >= 0x10)
+ ret = save_microcode_in_initrd_amd(cpuid_eax(1));
+ break;
+ default:
+ break;
+ }
+
+ initrd_gone = true;
+
+ return ret;
+}
+
+struct cpio_data find_microcode_in_initrd(const char *path, bool use_pa)
+{
+#ifdef CONFIG_BLK_DEV_INITRD
+ unsigned long start = 0;
+ size_t size;
+
+#ifdef CONFIG_X86_32
+ struct boot_params *params;
+
+ if (use_pa)
+ params = (struct boot_params *)__pa_nodebug(&boot_params);
+ else
+ params = &boot_params;
+
+ size = params->hdr.ramdisk_size;
+
+ /*
+ * Set start only if we have an initrd image. We cannot use initrd_start
+ * because it is not set that early yet.
+ */
+ if (size)
+ start = params->hdr.ramdisk_image;
+
+# else /* CONFIG_X86_64 */
+ size = (unsigned long)boot_params.ext_ramdisk_size << 32;
+ size |= boot_params.hdr.ramdisk_size;
+
+ if (size) {
+ start = (unsigned long)boot_params.ext_ramdisk_image << 32;
+ start |= boot_params.hdr.ramdisk_image;
+
+ start += PAGE_OFFSET;
+ }
+# endif
+
+ /*
+ * Fixup the start address: after reserve_initrd() runs, initrd_start
+ * has the virtual address of the beginning of the initrd. It also
+ * possibly relocates the ramdisk. In either case, initrd_start contains
+ * the updated address so use that instead.
+ *
+ * initrd_gone is for the hotplug case where we've thrown out initrd
+ * already.
+ */
+ if (!use_pa) {
+ if (initrd_gone)
+ return (struct cpio_data){ NULL, 0, "" };
+ if (initrd_start)
+ start = initrd_start;
+ } else {
+ /*
+ * The picture with physical addresses is a bit different: we
+ * need to get the *physical* address to which the ramdisk was
+ * relocated, i.e., relocated_ramdisk (not initrd_start) and
+ * since we're running from physical addresses, we need to access
+ * relocated_ramdisk through its *physical* address too.
+ */
+ u64 *rr = (u64 *)__pa_nodebug(&relocated_ramdisk);
+ if (*rr)
+ start = *rr;
+ }
+
+ return find_cpio_data(path, (void *)start, size, NULL);
+#else /* !CONFIG_BLK_DEV_INITRD */
+ return (struct cpio_data){ NULL, 0, "" };
+#endif
+}
+
+void reload_early_microcode(unsigned int cpu)
+{
+ int vendor, family;
+
+ vendor = x86_cpuid_vendor();
+ family = x86_cpuid_family();
+
+ switch (vendor) {
+ case X86_VENDOR_INTEL:
+ if (family >= 6)
+ reload_ucode_intel();
+ break;
+ case X86_VENDOR_AMD:
+ if (family >= 0x10)
+ reload_ucode_amd(cpu);
+ break;
+ default:
+ break;
+ }
+}
+
+/* fake device for request_firmware */
+static struct platform_device *microcode_pdev;
+
+#ifdef CONFIG_MICROCODE_LATE_LOADING
+/*
+ * Late loading dance. Why the heavy-handed stomp_machine effort?
+ *
+ * - HT siblings must be idle and not execute other code while the other sibling
+ * is loading microcode in order to avoid any negative interactions caused by
+ * the loading.
+ *
+ * - In addition, microcode update on the cores must be serialized until this
+ * requirement can be relaxed in the future. Right now, this is conservative
+ * and good.
+ */
+#define SPINUNIT 100 /* 100 nsec */
+
+static int check_online_cpus(void)
+{
+ unsigned int cpu;
+
+ /*
+ * Make sure all CPUs are online. It's fine for SMT to be disabled if
+ * all the primary threads are still online.
+ */
+ for_each_present_cpu(cpu) {
+ if (topology_is_primary_thread(cpu) && !cpu_online(cpu)) {
+ pr_err("Not all CPUs online, aborting microcode update.\n");
+ return -EINVAL;
+ }
+ }
+
+ return 0;
+}
+
+static atomic_t late_cpus_in;
+static atomic_t late_cpus_out;
+
+static int __wait_for_cpus(atomic_t *t, long long timeout)
+{
+ int all_cpus = num_online_cpus();
+
+ atomic_inc(t);
+
+ while (atomic_read(t) < all_cpus) {
+ if (timeout < SPINUNIT) {
+ pr_err("Timeout while waiting for CPUs rendezvous, remaining: %d\n",
+ all_cpus - atomic_read(t));
+ return 1;
+ }
+
+ ndelay(SPINUNIT);
+ timeout -= SPINUNIT;
+
+ touch_nmi_watchdog();
+ }
+ return 0;
+}
+
+/*
+ * Returns:
+ * < 0 - on error
+ * 0 - success (no update done or microcode was updated)
+ */
+static int __reload_late(void *info)
+{
+ int cpu = smp_processor_id();
+ enum ucode_state err;
+ int ret = 0;
+
+ /*
+ * Wait for all CPUs to arrive. A load will not be attempted unless all
+ * CPUs show up.
+ * */
+ if (__wait_for_cpus(&late_cpus_in, NSEC_PER_SEC))
+ return -1;
+
+ /*
+ * On an SMT system, it suffices to load the microcode on one sibling of
+ * the core because the microcode engine is shared between the threads.
+ * Synchronization still needs to take place so that no concurrent
+ * loading attempts happen on multiple threads of an SMT core. See
+ * below.
+ */
+ if (cpumask_first(topology_sibling_cpumask(cpu)) == cpu)
+ err = microcode_ops->apply_microcode(cpu);
+ else
+ goto wait_for_siblings;
+
+ if (err >= UCODE_NFOUND) {
+ if (err == UCODE_ERROR) {
+ pr_warn("Error reloading microcode on CPU %d\n", cpu);
+ ret = -1;
+ }
+ }
+
+wait_for_siblings:
+ if (__wait_for_cpus(&late_cpus_out, NSEC_PER_SEC))
+ panic("Timeout during microcode update!\n");
+
+ /*
+ * At least one thread has completed update on each core.
+ * For others, simply call the update to make sure the
+ * per-cpu cpuinfo can be updated with right microcode
+ * revision.
+ */
+ if (cpumask_first(topology_sibling_cpumask(cpu)) != cpu)
+ err = microcode_ops->apply_microcode(cpu);
+
+ return ret;
+}
+
+/*
+ * Reload microcode late on all CPUs. Wait for a sec until they
+ * all gather together.
+ */
+static int microcode_reload_late(void)
+{
+ int old = boot_cpu_data.microcode, ret;
+ struct cpuinfo_x86 prev_info;
+
+ pr_err("Attempting late microcode loading - it is dangerous and taints the kernel.\n");
+ pr_err("You should switch to early loading, if possible.\n");
+
+ atomic_set(&late_cpus_in, 0);
+ atomic_set(&late_cpus_out, 0);
+
+ /*
+ * Take a snapshot before the microcode update in order to compare and
+ * check whether any bits changed after an update.
+ */
+ store_cpu_caps(&prev_info);
+
+ ret = stop_machine_cpuslocked(__reload_late, NULL, cpu_online_mask);
+ if (!ret) {
+ pr_info("Reload succeeded, microcode revision: 0x%x -> 0x%x\n",
+ old, boot_cpu_data.microcode);
+ microcode_check(&prev_info);
+ } else {
+ pr_info("Reload failed, current microcode revision: 0x%x\n",
+ boot_cpu_data.microcode);
+ }
+
+ return ret;
+}
+
+static ssize_t reload_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ enum ucode_state tmp_ret = UCODE_OK;
+ int bsp = boot_cpu_data.cpu_index;
+ unsigned long val;
+ ssize_t ret = 0;
+
+ ret = kstrtoul(buf, 0, &val);
+ if (ret || val != 1)
+ return -EINVAL;
+
+ cpus_read_lock();
+
+ ret = check_online_cpus();
+ if (ret)
+ goto put;
+
+ tmp_ret = microcode_ops->request_microcode_fw(bsp, &microcode_pdev->dev);
+ if (tmp_ret != UCODE_NEW)
+ goto put;
+
+ mutex_lock(&microcode_mutex);
+ ret = microcode_reload_late();
+ mutex_unlock(&microcode_mutex);
+
+put:
+ cpus_read_unlock();
+
+ if (ret == 0)
+ ret = size;
+
+ add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK);
+
+ return ret;
+}
+
+static DEVICE_ATTR_WO(reload);
+#endif
+
+static ssize_t version_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct ucode_cpu_info *uci = ucode_cpu_info + dev->id;
+
+ return sprintf(buf, "0x%x\n", uci->cpu_sig.rev);
+}
+
+static ssize_t processor_flags_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct ucode_cpu_info *uci = ucode_cpu_info + dev->id;
+
+ return sprintf(buf, "0x%x\n", uci->cpu_sig.pf);
+}
+
+static DEVICE_ATTR_RO(version);
+static DEVICE_ATTR_RO(processor_flags);
+
+static struct attribute *mc_default_attrs[] = {
+ &dev_attr_version.attr,
+ &dev_attr_processor_flags.attr,
+ NULL
+};
+
+static const struct attribute_group mc_attr_group = {
+ .attrs = mc_default_attrs,
+ .name = "microcode",
+};
+
+static void microcode_fini_cpu(int cpu)
+{
+ if (microcode_ops->microcode_fini_cpu)
+ microcode_ops->microcode_fini_cpu(cpu);
+}
+
+static enum ucode_state microcode_init_cpu(int cpu)
+{
+ struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
+
+ memset(uci, 0, sizeof(*uci));
+
+ microcode_ops->collect_cpu_info(cpu, &uci->cpu_sig);
+
+ return microcode_ops->apply_microcode(cpu);
+}
+
+/**
+ * microcode_bsp_resume - Update boot CPU microcode during resume.
+ */
+void microcode_bsp_resume(void)
+{
+ int cpu = smp_processor_id();
+ struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
+
+ if (uci->mc)
+ microcode_ops->apply_microcode(cpu);
+ else
+ reload_early_microcode(cpu);
+}
+
+static struct syscore_ops mc_syscore_ops = {
+ .resume = microcode_bsp_resume,
+};
+
+static int mc_cpu_starting(unsigned int cpu)
+{
+ enum ucode_state err = microcode_ops->apply_microcode(cpu);
+
+ pr_debug("%s: CPU%d, err: %d\n", __func__, cpu, err);
+
+ return err == UCODE_ERROR;
+}
+
+static int mc_cpu_online(unsigned int cpu)
+{
+ struct device *dev = get_cpu_device(cpu);
+
+ if (sysfs_create_group(&dev->kobj, &mc_attr_group))
+ pr_err("Failed to create group for CPU%d\n", cpu);
+ return 0;
+}
+
+static int mc_cpu_down_prep(unsigned int cpu)
+{
+ struct device *dev;
+
+ dev = get_cpu_device(cpu);
+
+ microcode_fini_cpu(cpu);
+
+ /* Suspend is in progress, only remove the interface */
+ sysfs_remove_group(&dev->kobj, &mc_attr_group);
+ pr_debug("%s: CPU%d\n", __func__, cpu);
+
+ return 0;
+}
+
+static void setup_online_cpu(struct work_struct *work)
+{
+ int cpu = smp_processor_id();
+ enum ucode_state err;
+
+ err = microcode_init_cpu(cpu);
+ if (err == UCODE_ERROR) {
+ pr_err("Error applying microcode on CPU%d\n", cpu);
+ return;
+ }
+
+ mc_cpu_online(cpu);
+}
+
+static struct attribute *cpu_root_microcode_attrs[] = {
+#ifdef CONFIG_MICROCODE_LATE_LOADING
+ &dev_attr_reload.attr,
+#endif
+ NULL
+};
+
+static const struct attribute_group cpu_root_microcode_group = {
+ .name = "microcode",
+ .attrs = cpu_root_microcode_attrs,
+};
+
+static int __init microcode_init(void)
+{
+ struct cpuinfo_x86 *c = &boot_cpu_data;
+ int error;
+
+ if (dis_ucode_ldr)
+ return -EINVAL;
+
+ if (c->x86_vendor == X86_VENDOR_INTEL)
+ microcode_ops = init_intel_microcode();
+ else if (c->x86_vendor == X86_VENDOR_AMD)
+ microcode_ops = init_amd_microcode();
+ else
+ pr_err("no support for this CPU vendor\n");
+
+ if (!microcode_ops)
+ return -ENODEV;
+
+ microcode_pdev = platform_device_register_simple("microcode", -1, NULL, 0);
+ if (IS_ERR(microcode_pdev))
+ return PTR_ERR(microcode_pdev);
+
+ error = sysfs_create_group(&cpu_subsys.dev_root->kobj, &cpu_root_microcode_group);
+ if (error) {
+ pr_err("Error creating microcode group!\n");
+ goto out_pdev;
+ }
+
+ /* Do per-CPU setup */
+ schedule_on_each_cpu(setup_online_cpu);
+
+ register_syscore_ops(&mc_syscore_ops);
+ cpuhp_setup_state_nocalls(CPUHP_AP_MICROCODE_LOADER, "x86/microcode:starting",
+ mc_cpu_starting, NULL);
+ cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "x86/microcode:online",
+ mc_cpu_online, mc_cpu_down_prep);
+
+ pr_info("Microcode Update Driver: v%s.", DRIVER_VERSION);
+
+ return 0;
+
+ out_pdev:
+ platform_device_unregister(microcode_pdev);
+ return error;
+
+}
+fs_initcall(save_microcode_in_initrd);
+late_initcall(microcode_init);