summaryrefslogtreecommitdiff
path: root/arch/x86/kernel/cpu/microcode
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/kernel/cpu/microcode')
-rw-r--r--arch/x86/kernel/cpu/microcode/amd.c113
-rw-r--r--arch/x86/kernel/cpu/microcode/core.c13
-rw-r--r--arch/x86/kernel/cpu/microcode/intel.c362
-rw-r--r--arch/x86/kernel/cpu/microcode/internal.h4
4 files changed, 449 insertions, 43 deletions
diff --git a/arch/x86/kernel/cpu/microcode/amd.c b/arch/x86/kernel/cpu/microcode/amd.c
index a881bf4c2011..3821a985f4ff 100644
--- a/arch/x86/kernel/cpu/microcode/amd.c
+++ b/arch/x86/kernel/cpu/microcode/amd.c
@@ -186,50 +186,61 @@ static u32 cpuid_to_ucode_rev(unsigned int val)
return p.ucode_rev;
}
+static u32 get_cutoff_revision(u32 rev)
+{
+ switch (rev >> 8) {
+ case 0x80012: return 0x8001277; break;
+ case 0x80082: return 0x800820f; break;
+ case 0x83010: return 0x830107c; break;
+ case 0x86001: return 0x860010e; break;
+ case 0x86081: return 0x8608108; break;
+ case 0x87010: return 0x8701034; break;
+ case 0x8a000: return 0x8a0000a; break;
+ case 0xa0010: return 0xa00107a; break;
+ case 0xa0011: return 0xa0011da; break;
+ case 0xa0012: return 0xa001243; break;
+ case 0xa0082: return 0xa00820e; break;
+ case 0xa1011: return 0xa101153; break;
+ case 0xa1012: return 0xa10124e; break;
+ case 0xa1081: return 0xa108109; break;
+ case 0xa2010: return 0xa20102f; break;
+ case 0xa2012: return 0xa201212; break;
+ case 0xa4041: return 0xa404109; break;
+ case 0xa5000: return 0xa500013; break;
+ case 0xa6012: return 0xa60120a; break;
+ case 0xa7041: return 0xa704109; break;
+ case 0xa7052: return 0xa705208; break;
+ case 0xa7080: return 0xa708009; break;
+ case 0xa70c0: return 0xa70C009; break;
+ case 0xaa001: return 0xaa00116; break;
+ case 0xaa002: return 0xaa00218; break;
+ case 0xb0021: return 0xb002146; break;
+ case 0xb0081: return 0xb008111; break;
+ case 0xb1010: return 0xb101046; break;
+ case 0xb2040: return 0xb204031; break;
+ case 0xb4040: return 0xb404031; break;
+ case 0xb4041: return 0xb404101; break;
+ case 0xb6000: return 0xb600031; break;
+ case 0xb6080: return 0xb608031; break;
+ case 0xb7000: return 0xb700031; break;
+ default: break;
+
+ }
+ return 0;
+}
+
static bool need_sha_check(u32 cur_rev)
{
+ u32 cutoff;
+
if (!cur_rev) {
cur_rev = cpuid_to_ucode_rev(bsp_cpuid_1_eax);
pr_info_once("No current revision, generating the lowest one: 0x%x\n", cur_rev);
}
- switch (cur_rev >> 8) {
- case 0x80012: return cur_rev <= 0x8001277; break;
- case 0x80082: return cur_rev <= 0x800820f; break;
- case 0x83010: return cur_rev <= 0x830107c; break;
- case 0x86001: return cur_rev <= 0x860010e; break;
- case 0x86081: return cur_rev <= 0x8608108; break;
- case 0x87010: return cur_rev <= 0x8701034; break;
- case 0x8a000: return cur_rev <= 0x8a0000a; break;
- case 0xa0010: return cur_rev <= 0xa00107a; break;
- case 0xa0011: return cur_rev <= 0xa0011da; break;
- case 0xa0012: return cur_rev <= 0xa001243; break;
- case 0xa0082: return cur_rev <= 0xa00820e; break;
- case 0xa1011: return cur_rev <= 0xa101153; break;
- case 0xa1012: return cur_rev <= 0xa10124e; break;
- case 0xa1081: return cur_rev <= 0xa108109; break;
- case 0xa2010: return cur_rev <= 0xa20102f; break;
- case 0xa2012: return cur_rev <= 0xa201212; break;
- case 0xa4041: return cur_rev <= 0xa404109; break;
- case 0xa5000: return cur_rev <= 0xa500013; break;
- case 0xa6012: return cur_rev <= 0xa60120a; break;
- case 0xa7041: return cur_rev <= 0xa704109; break;
- case 0xa7052: return cur_rev <= 0xa705208; break;
- case 0xa7080: return cur_rev <= 0xa708009; break;
- case 0xa70c0: return cur_rev <= 0xa70C009; break;
- case 0xaa001: return cur_rev <= 0xaa00116; break;
- case 0xaa002: return cur_rev <= 0xaa00218; break;
- case 0xb0021: return cur_rev <= 0xb002146; break;
- case 0xb0081: return cur_rev <= 0xb008111; break;
- case 0xb1010: return cur_rev <= 0xb101046; break;
- case 0xb2040: return cur_rev <= 0xb204031; break;
- case 0xb4040: return cur_rev <= 0xb404031; break;
- case 0xb4041: return cur_rev <= 0xb404101; break;
- case 0xb6000: return cur_rev <= 0xb600031; break;
- case 0xb6080: return cur_rev <= 0xb608031; break;
- case 0xb7000: return cur_rev <= 0xb700031; break;
- default: break;
- }
+ cutoff = get_cutoff_revision(cur_rev);
+ if (cutoff)
+ return cur_rev <= cutoff;
pr_info("You should not be seeing this. Please send the following couple of lines to x86-<at>-kernel.org\n");
pr_info("CPUID(1).EAX: 0x%x, current revision: 0x%x\n", bsp_cpuid_1_eax, cur_rev);
@@ -494,6 +505,7 @@ static int verify_patch(const u8 *buf, size_t buf_size, u32 *patch_size)
{
u8 family = x86_family(bsp_cpuid_1_eax);
struct microcode_header_amd *mc_hdr;
+ u32 cur_rev, cutoff, patch_rev;
u32 sh_psize;
u16 proc_id;
u8 patch_fam;
@@ -533,11 +545,32 @@ static int verify_patch(const u8 *buf, size_t buf_size, u32 *patch_size)
proc_id = mc_hdr->processor_rev_id;
patch_fam = 0xf + (proc_id >> 12);
- ucode_dbg("Patch-ID 0x%08x: family: 0x%x\n", mc_hdr->patch_id, patch_fam);
-
if (patch_fam != family)
return 1;
+ cur_rev = get_patch_level();
+
+ /* No cutoff revision means old/unaffected by signing algorithm weakness => matches */
+ cutoff = get_cutoff_revision(cur_rev);
+ if (!cutoff)
+ goto ok;
+
+ patch_rev = mc_hdr->patch_id;
+
+ ucode_dbg("cur_rev: 0x%x, cutoff: 0x%x, patch_rev: 0x%x\n",
+ cur_rev, cutoff, patch_rev);
+
+ if (cur_rev <= cutoff && patch_rev <= cutoff)
+ goto ok;
+
+ if (cur_rev > cutoff && patch_rev > cutoff)
+ goto ok;
+
+ return 1;
+
+ok:
+ ucode_dbg("Patch-ID 0x%08x: family: 0x%x\n", mc_hdr->patch_id, patch_fam);
+
return 0;
}
@@ -606,8 +639,6 @@ static size_t parse_container(u8 *ucode, size_t size, struct cont_desc *desc)
mc = (struct microcode_amd *)(buf + SECTION_HDR_SIZE);
- ucode_dbg("patch_id: 0x%x\n", mc->hdr.patch_id);
-
if (mc_patch_matches(mc, eq_id)) {
desc->psize = patch_size;
desc->mc = mc;
diff --git a/arch/x86/kernel/cpu/microcode/core.c b/arch/x86/kernel/cpu/microcode/core.c
index f75c140906d0..ccc83b0bf63c 100644
--- a/arch/x86/kernel/cpu/microcode/core.c
+++ b/arch/x86/kernel/cpu/microcode/core.c
@@ -136,7 +136,7 @@ bool __init microcode_loader_disabled(void)
return dis_ucode_ldr;
}
-static void early_parse_cmdline(void)
+static void __init early_parse_cmdline(void)
{
char cmd_buf[64] = {};
char *s, *p = cmd_buf;
@@ -589,6 +589,17 @@ static int load_late_stop_cpus(bool is_safe)
pr_err("You should switch to early loading, if possible.\n");
}
+ /*
+ * Pre-load the microcode image into a staging device. This
+ * process is preemptible and does not require stopping CPUs.
+ * Successful staging simplifies the subsequent late-loading
+ * process, reducing rendezvous time.
+ *
+ * Even if the transfer fails, the update will proceed as usual.
+ */
+ if (microcode_ops->use_staging)
+ microcode_ops->stage_microcode();
+
atomic_set(&late_cpus_in, num_online_cpus());
atomic_set(&offline_in_nmi, 0);
loops_per_usec = loops_per_jiffy / (TICK_NSEC / 1000);
diff --git a/arch/x86/kernel/cpu/microcode/intel.c b/arch/x86/kernel/cpu/microcode/intel.c
index 371ca6eac00e..8744f3adc2a0 100644
--- a/arch/x86/kernel/cpu/microcode/intel.c
+++ b/arch/x86/kernel/cpu/microcode/intel.c
@@ -13,12 +13,15 @@
#define pr_fmt(fmt) "microcode: " fmt
#include <linux/earlycpio.h>
#include <linux/firmware.h>
+#include <linux/pci_ids.h>
#include <linux/uaccess.h>
#include <linux/initrd.h>
#include <linux/kernel.h>
+#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/cpu.h>
#include <linux/uio.h>
+#include <linux/io.h>
#include <linux/mm.h>
#include <asm/cpu_device_id.h>
@@ -33,6 +36,38 @@ static const char ucode_path[] = "kernel/x86/microcode/GenuineIntel.bin";
#define UCODE_BSP_LOADED ((struct microcode_intel *)0x1UL)
+/* Defines for the microcode staging mailbox interface */
+#define MBOX_REG_NUM 4
+#define MBOX_REG_SIZE sizeof(u32)
+
+#define MBOX_CONTROL_OFFSET 0x0
+#define MBOX_STATUS_OFFSET 0x4
+#define MBOX_WRDATA_OFFSET 0x8
+#define MBOX_RDDATA_OFFSET 0xc
+
+#define MASK_MBOX_CTRL_ABORT BIT(0)
+#define MASK_MBOX_CTRL_GO BIT(31)
+
+#define MASK_MBOX_STATUS_ERROR BIT(2)
+#define MASK_MBOX_STATUS_READY BIT(31)
+
+#define MASK_MBOX_RESP_SUCCESS BIT(0)
+#define MASK_MBOX_RESP_PROGRESS BIT(1)
+#define MASK_MBOX_RESP_ERROR BIT(2)
+
+#define MBOX_CMD_LOAD 0x3
+#define MBOX_OBJ_STAGING 0xb
+#define MBOX_HEADER(size) ((PCI_VENDOR_ID_INTEL) | \
+ (MBOX_OBJ_STAGING << 16) | \
+ ((u64)((size) / sizeof(u32)) << 32))
+
+/* The size of each mailbox header */
+#define MBOX_HEADER_SIZE sizeof(u64)
+/* The size of staging hardware response */
+#define MBOX_RESPONSE_SIZE sizeof(u64)
+
+#define MBOX_XACTION_TIMEOUT_MS (10 * MSEC_PER_SEC)
+
/* Current microcode patch used in early patching on the APs. */
static struct microcode_intel *ucode_patch_va __read_mostly;
static struct microcode_intel *ucode_patch_late __read_mostly;
@@ -54,6 +89,23 @@ struct extended_sigtable {
struct extended_signature sigs[];
};
+/**
+ * struct staging_state - Track the current staging process state
+ *
+ * @mmio_base: MMIO base address for staging
+ * @ucode_len: Total size of the microcode image
+ * @chunk_size: Size of each data piece
+ * @bytes_sent: Total bytes transmitted so far
+ * @offset: Current offset in the microcode image
+ */
+struct staging_state {
+ void __iomem *mmio_base;
+ unsigned int ucode_len;
+ unsigned int chunk_size;
+ unsigned int bytes_sent;
+ unsigned int offset;
+};
+
#define DEFAULT_UCODE_TOTALSIZE (DEFAULT_UCODE_DATASIZE + MC_HEADER_SIZE)
#define EXT_HEADER_SIZE (sizeof(struct extended_sigtable))
#define EXT_SIGNATURE_SIZE (sizeof(struct extended_signature))
@@ -299,6 +351,298 @@ static __init struct microcode_intel *scan_microcode(void *data, size_t size,
return size ? NULL : patch;
}
+static inline u32 read_mbox_dword(void __iomem *mmio_base)
+{
+ u32 dword = readl(mmio_base + MBOX_RDDATA_OFFSET);
+
+ /* Acknowledge read completion to the staging hardware */
+ writel(0, mmio_base + MBOX_RDDATA_OFFSET);
+ return dword;
+}
+
+static inline void write_mbox_dword(void __iomem *mmio_base, u32 dword)
+{
+ writel(dword, mmio_base + MBOX_WRDATA_OFFSET);
+}
+
+static inline u64 read_mbox_header(void __iomem *mmio_base)
+{
+ u32 high, low;
+
+ low = read_mbox_dword(mmio_base);
+ high = read_mbox_dword(mmio_base);
+
+ return ((u64)high << 32) | low;
+}
+
+static inline void write_mbox_header(void __iomem *mmio_base, u64 value)
+{
+ write_mbox_dword(mmio_base, value);
+ write_mbox_dword(mmio_base, value >> 32);
+}
+
+static void write_mbox_data(void __iomem *mmio_base, u32 *chunk, unsigned int chunk_bytes)
+{
+ int i;
+
+ /*
+ * The MMIO space is mapped as Uncached (UC). Each write arrives
+ * at the device as an individual transaction in program order.
+ * The device can then reassemble the sequence accordingly.
+ */
+ for (i = 0; i < chunk_bytes / sizeof(u32); i++)
+ write_mbox_dword(mmio_base, chunk[i]);
+}
+
+/*
+ * Prepare for a new microcode transfer: reset hardware and record the
+ * image size.
+ */
+static void init_stage(struct staging_state *ss)
+{
+ ss->ucode_len = get_totalsize(&ucode_patch_late->hdr);
+
+ /*
+ * Abort any ongoing process, effectively resetting the device.
+ * Unlike regular mailbox data processing requests, this
+ * operation does not require a status check.
+ */
+ writel(MASK_MBOX_CTRL_ABORT, ss->mmio_base + MBOX_CONTROL_OFFSET);
+}
+
+/*
+ * Update the chunk size and decide whether another chunk can be sent.
+ * This accounts for remaining data and retry limits.
+ */
+static bool can_send_next_chunk(struct staging_state *ss, int *err)
+{
+ /* A page size or remaining bytes if this is the final chunk */
+ ss->chunk_size = min(PAGE_SIZE, ss->ucode_len - ss->offset);
+
+ /*
+ * Each microcode image is divided into chunks, each at most
+ * one page size. A 10-chunk image would typically require 10
+ * transactions.
+ *
+ * However, the hardware managing the mailbox has limited
+ * resources and may not cache the entire image, potentially
+ * requesting the same chunk multiple times.
+ *
+ * To tolerate this behavior, allow up to twice the expected
+ * number of transactions (i.e., a 10-chunk image can take up to
+ * 20 attempts).
+ *
+ * If the number of attempts exceeds this limit, treat it as
+ * exceeding the maximum allowed transfer size.
+ */
+ if (ss->bytes_sent + ss->chunk_size > ss->ucode_len * 2) {
+ *err = -EMSGSIZE;
+ return false;
+ }
+
+ *err = 0;
+ return true;
+}
+
+/*
+ * The hardware indicates completion by returning a sentinel end offset.
+ */
+static inline bool is_end_offset(u32 offset)
+{
+ return offset == UINT_MAX;
+}
+
+/*
+ * Determine whether staging is complete: either the hardware signaled
+ * the end offset, or no more transactions are permitted (retry limit
+ * reached).
+ */
+static inline bool staging_is_complete(struct staging_state *ss, int *err)
+{
+ return is_end_offset(ss->offset) || !can_send_next_chunk(ss, err);
+}
+
+/*
+ * Wait for the hardware to complete a transaction.
+ * Return 0 on success, or an error code on failure.
+ */
+static int wait_for_transaction(struct staging_state *ss)
+{
+ u32 timeout, status;
+
+ /* Allow time for hardware to complete the operation: */
+ for (timeout = 0; timeout < MBOX_XACTION_TIMEOUT_MS; timeout++) {
+ msleep(1);
+
+ status = readl(ss->mmio_base + MBOX_STATUS_OFFSET);
+ /* Break out early if the hardware is ready: */
+ if (status & MASK_MBOX_STATUS_READY)
+ break;
+ }
+
+ /* Check for explicit error response */
+ if (status & MASK_MBOX_STATUS_ERROR)
+ return -EIO;
+
+ /*
+ * Hardware has neither responded to the action nor signaled any
+ * error. Treat this as a timeout.
+ */
+ if (!(status & MASK_MBOX_STATUS_READY))
+ return -ETIMEDOUT;
+
+ return 0;
+}
+
+/*
+ * Transmit a chunk of the microcode image to the hardware.
+ * Return 0 on success, or an error code on failure.
+ */
+static int send_data_chunk(struct staging_state *ss, void *ucode_ptr)
+{
+ u32 *src_chunk = ucode_ptr + ss->offset;
+ u16 mbox_size;
+
+ /*
+ * Write a 'request' mailbox object in this order:
+ * 1. Mailbox header includes total size
+ * 2. Command header specifies the load operation
+ * 3. Data section contains a microcode chunk
+ *
+ * Thus, the mailbox size is two headers plus the chunk size.
+ */
+ mbox_size = MBOX_HEADER_SIZE * 2 + ss->chunk_size;
+ write_mbox_header(ss->mmio_base, MBOX_HEADER(mbox_size));
+ write_mbox_header(ss->mmio_base, MBOX_CMD_LOAD);
+ write_mbox_data(ss->mmio_base, src_chunk, ss->chunk_size);
+ ss->bytes_sent += ss->chunk_size;
+
+ /* Notify the hardware that the mailbox is ready for processing. */
+ writel(MASK_MBOX_CTRL_GO, ss->mmio_base + MBOX_CONTROL_OFFSET);
+
+ return wait_for_transaction(ss);
+}
+
+/*
+ * Retrieve the next offset from the hardware response.
+ * Return 0 on success, or an error code on failure.
+ */
+static int fetch_next_offset(struct staging_state *ss)
+{
+ const u64 expected_header = MBOX_HEADER(MBOX_HEADER_SIZE + MBOX_RESPONSE_SIZE);
+ u32 offset, status;
+ u64 header;
+
+ /*
+ * The 'response' mailbox returns three fields, in order:
+ * 1. Header
+ * 2. Next offset in the microcode image
+ * 3. Status flags
+ */
+ header = read_mbox_header(ss->mmio_base);
+ offset = read_mbox_dword(ss->mmio_base);
+ status = read_mbox_dword(ss->mmio_base);
+
+ /* All valid responses must start with the expected header. */
+ if (header != expected_header) {
+ pr_err_once("staging: invalid response header (0x%llx)\n", header);
+ return -EBADR;
+ }
+
+ /*
+ * Verify the offset: If not at the end marker, it must not
+ * exceed the microcode image length.
+ */
+ if (!is_end_offset(offset) && offset > ss->ucode_len) {
+ pr_err_once("staging: invalid offset (%u) past the image end (%u)\n",
+ offset, ss->ucode_len);
+ return -EINVAL;
+ }
+
+ /* Hardware may report errors explicitly in the status field */
+ if (status & MASK_MBOX_RESP_ERROR)
+ return -EPROTO;
+
+ ss->offset = offset;
+ return 0;
+}
+
+/*
+ * Handle the staging process using the mailbox MMIO interface. The
+ * microcode image is transferred in chunks until completion.
+ * Return 0 on success or an error code on failure.
+ */
+static int do_stage(u64 mmio_pa)
+{
+ struct staging_state ss = {};
+ int err;
+
+ ss.mmio_base = ioremap(mmio_pa, MBOX_REG_NUM * MBOX_REG_SIZE);
+ if (WARN_ON_ONCE(!ss.mmio_base))
+ return -EADDRNOTAVAIL;
+
+ init_stage(&ss);
+
+ /* Perform the staging process while within the retry limit */
+ while (!staging_is_complete(&ss, &err)) {
+ /* Send a chunk of microcode each time: */
+ err = send_data_chunk(&ss, ucode_patch_late);
+ if (err)
+ break;
+ /*
+ * Then, ask the hardware which piece of the image it
+ * needs next. The same piece may be sent more than once.
+ */
+ err = fetch_next_offset(&ss);
+ if (err)
+ break;
+ }
+
+ iounmap(ss.mmio_base);
+
+ return err;
+}
+
+static void stage_microcode(void)
+{
+ unsigned int pkg_id = UINT_MAX;
+ int cpu, err;
+ u64 mmio_pa;
+
+ if (!IS_ALIGNED(get_totalsize(&ucode_patch_late->hdr), sizeof(u32))) {
+ pr_err("Microcode image 32-bit misaligned (0x%x), staging failed.\n",
+ get_totalsize(&ucode_patch_late->hdr));
+ return;
+ }
+
+ lockdep_assert_cpus_held();
+
+ /*
+ * The MMIO address is unique per package, and all the SMT
+ * primary threads are online here. Find each MMIO space by
+ * their package IDs to avoid duplicate staging.
+ */
+ for_each_cpu(cpu, cpu_primary_thread_mask) {
+ if (topology_logical_package_id(cpu) == pkg_id)
+ continue;
+
+ pkg_id = topology_logical_package_id(cpu);
+
+ err = rdmsrq_on_cpu(cpu, MSR_IA32_MCU_STAGING_MBOX_ADDR, &mmio_pa);
+ if (WARN_ON_ONCE(err))
+ return;
+
+ err = do_stage(mmio_pa);
+ if (err) {
+ pr_err("Error: staging failed (%d) for CPU%d at package %u.\n",
+ err, cpu, pkg_id);
+ return;
+ }
+ }
+
+ pr_info("Staging of patch revision 0x%x succeeded.\n", ucode_patch_late->hdr.rev);
+}
+
static enum ucode_state __apply_microcode(struct ucode_cpu_info *uci,
struct microcode_intel *mc,
u32 *cur_rev)
@@ -627,6 +971,7 @@ static struct microcode_ops microcode_intel_ops = {
.collect_cpu_info = collect_cpu_info,
.apply_microcode = apply_microcode_late,
.finalize_late_load = finalize_late_load,
+ .stage_microcode = stage_microcode,
.use_nmi = IS_ENABLED(CONFIG_X86_64),
};
@@ -638,6 +983,18 @@ static __init void calc_llc_size_per_core(struct cpuinfo_x86 *c)
llc_size_per_core = (unsigned int)llc_size;
}
+static __init bool staging_available(void)
+{
+ u64 val;
+
+ val = x86_read_arch_cap_msr();
+ if (!(val & ARCH_CAP_MCU_ENUM))
+ return false;
+
+ rdmsrq(MSR_IA32_MCU_ENUMERATION, val);
+ return !!(val & MCU_STAGING);
+}
+
struct microcode_ops * __init init_intel_microcode(void)
{
struct cpuinfo_x86 *c = &boot_cpu_data;
@@ -648,6 +1005,11 @@ struct microcode_ops * __init init_intel_microcode(void)
return NULL;
}
+ if (staging_available()) {
+ microcode_intel_ops.use_staging = true;
+ pr_info("Enabled staging feature.\n");
+ }
+
calc_llc_size_per_core(c);
return &microcode_intel_ops;
diff --git a/arch/x86/kernel/cpu/microcode/internal.h b/arch/x86/kernel/cpu/microcode/internal.h
index ae8dbc2b908d..a10b547eda1e 100644
--- a/arch/x86/kernel/cpu/microcode/internal.h
+++ b/arch/x86/kernel/cpu/microcode/internal.h
@@ -31,10 +31,12 @@ struct microcode_ops {
* See also the "Synchronization" section in microcode_core.c.
*/
enum ucode_state (*apply_microcode)(int cpu);
+ void (*stage_microcode)(void);
int (*collect_cpu_info)(int cpu, struct cpu_signature *csig);
void (*finalize_late_load)(int result);
unsigned int nmi_safe : 1,
- use_nmi : 1;
+ use_nmi : 1,
+ use_staging : 1;
};
struct early_load_data {