From d4f99f98cc9d68fc2ee2c9659dc112b3c05fa08a Mon Sep 17 00:00:00 2001
From: Peter Jung <admin@ptr1337.dev>
Date: Sun, 20 Apr 2025 15:32:39 +0200
Subject: [PATCH 7/9] fixes

Signed-off-by: Peter Jung <admin@ptr1337.dev>
---
 .../ABI/testing/sysfs-devices-system-cpu      |   1 +
 .../admin-guide/hw-vuln/old_microcode.rst     |  21 +++
 arch/Kconfig                                  |   4 +-
 arch/x86/include/asm/cpufeatures.h            |   2 +
 arch/x86/kernel/cpu/bugs.c                    |  16 ++
 arch/x86/kernel/cpu/common.c                  |  42 +++++
 .../kernel/cpu/microcode/intel-ucode-defs.h   | 150 ++++++++++++++++++
 arch/x86/tools/insn_decoder_test.c            |   3 +-
 crypto/crc32c_generic.c                       |   1 +
 drivers/base/cpu.c                            |   3 +
 drivers/gpu/drm/i915/display/intel_dsb.c      |   4 +
 include/linux/cpu.h                           |   2 +
 lib/Kconfig.debug                             |   9 ++
 lib/Makefile                                  |   2 +
 lib/longest_symbol_kunit.c                    |  82 ++++++++++
 scripts/package/PKGBUILD                      |   5 +
 16 files changed, 344 insertions(+), 3 deletions(-)
 create mode 100644 Documentation/admin-guide/hw-vuln/old_microcode.rst
 create mode 100644 arch/x86/kernel/cpu/microcode/intel-ucode-defs.h
 create mode 100644 lib/longest_symbol_kunit.c

diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu
index 206079d3bd5b..766a9747b154 100644
--- a/Documentation/ABI/testing/sysfs-devices-system-cpu
+++ b/Documentation/ABI/testing/sysfs-devices-system-cpu
@@ -516,6 +516,7 @@ What:		/sys/devices/system/cpu/vulnerabilities
 		/sys/devices/system/cpu/vulnerabilities/mds
 		/sys/devices/system/cpu/vulnerabilities/meltdown
 		/sys/devices/system/cpu/vulnerabilities/mmio_stale_data
+		/sys/devices/system/cpu/vulnerabilities/old_microcode
 		/sys/devices/system/cpu/vulnerabilities/reg_file_data_sampling
 		/sys/devices/system/cpu/vulnerabilities/retbleed
 		/sys/devices/system/cpu/vulnerabilities/spec_store_bypass
diff --git a/Documentation/admin-guide/hw-vuln/old_microcode.rst b/Documentation/admin-guide/hw-vuln/old_microcode.rst
new file mode 100644
index 000000000000..6ded8f86b8d0
--- /dev/null
+++ b/Documentation/admin-guide/hw-vuln/old_microcode.rst
@@ -0,0 +1,21 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+=============
+Old Microcode
+=============
+
+The kernel keeps a table of released microcode. Systems that had
+microcode older than this at boot will say "Vulnerable".  This means
+that the system was vulnerable to some known CPU issue. It could be
+security or functional, the kernel does not know or care.
+
+You should update the CPU microcode to mitigate any exposure. This is
+usually accomplished by updating the files in
+/lib/firmware/intel-ucode/ via normal distribution updates. Intel also
+distributes these files in a github repo:
+
+	https://github.com/intel/Intel-Linux-Processor-Microcode-Data-Files.git
+
+Just like all the other hardware vulnerabilities, exposure is
+determined at boot. Runtime microcode updates do not change the status
+of this vulnerability.
diff --git a/arch/Kconfig b/arch/Kconfig
index b8a4ff365582..9b087f9bb413 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -1137,7 +1137,7 @@ config ARCH_MMAP_RND_BITS
 	int "Number of bits to use for ASLR of mmap base address" if EXPERT
 	range ARCH_MMAP_RND_BITS_MIN ARCH_MMAP_RND_BITS_MAX
 	default ARCH_MMAP_RND_BITS_DEFAULT if ARCH_MMAP_RND_BITS_DEFAULT
-	default ARCH_MMAP_RND_BITS_MIN
+	default ARCH_MMAP_RND_BITS_MAX
 	depends on HAVE_ARCH_MMAP_RND_BITS
 	help
 	  This value can be used to select the number of bits to use to
@@ -1171,7 +1171,7 @@ config ARCH_MMAP_RND_COMPAT_BITS
 	int "Number of bits to use for ASLR of mmap base address for compatible applications" if EXPERT
 	range ARCH_MMAP_RND_COMPAT_BITS_MIN ARCH_MMAP_RND_COMPAT_BITS_MAX
 	default ARCH_MMAP_RND_COMPAT_BITS_DEFAULT if ARCH_MMAP_RND_COMPAT_BITS_DEFAULT
-	default ARCH_MMAP_RND_COMPAT_BITS_MIN
+	default ARCH_MMAP_RND_COMPAT_BITS_MAX
 	depends on HAVE_ARCH_MMAP_RND_COMPAT_BITS
 	help
 	  This value can be used to select the number of bits to use to
diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h
index 8c77b9337ca3..969322503927 100644
--- a/arch/x86/include/asm/cpufeatures.h
+++ b/arch/x86/include/asm/cpufeatures.h
@@ -536,4 +536,6 @@
 #define X86_BUG_RFDS			X86_BUG(1*32 + 2) /* "rfds" CPU is vulnerable to Register File Data Sampling */
 #define X86_BUG_BHI			X86_BUG(1*32 + 3) /* "bhi" CPU is affected by Branch History Injection */
 #define X86_BUG_IBPB_NO_RET	   	X86_BUG(1*32 + 4) /* "ibpb_no_ret" IBPB omits return target predictions */
+#define X86_BUG_SPECTRE_V2_USER		X86_BUG(1*32 + 5) /* "spectre_v2_user" CPU is affected by Spectre variant 2 attack between user processes */
+#define X86_BUG_OLD_MICROCODE		X86_BUG(1*32 + 6) /* "old_microcode" CPU has old microcode, it is surely vulnerable to something */
 #endif /* _ASM_X86_CPUFEATURES_H */
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index a5d0998d7604..c04a01b05157 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -2806,6 +2806,14 @@ static ssize_t rfds_show_state(char *buf)
 	return sysfs_emit(buf, "%s\n", rfds_strings[rfds_mitigation]);
 }
 
+static ssize_t old_microcode_show_state(char *buf)
+{
+	if (boot_cpu_has(X86_FEATURE_HYPERVISOR))
+		return sysfs_emit(buf, "Unknown: running under hypervisor");
+
+	return sysfs_emit(buf, "Vulnerable\n");
+}
+
 static char *stibp_state(void)
 {
 	if (spectre_v2_in_eibrs_mode(spectre_v2_enabled) &&
@@ -2988,6 +2996,9 @@ static ssize_t cpu_show_common(struct device *dev, struct device_attribute *attr
 	case X86_BUG_RFDS:
 		return rfds_show_state(buf);
 
+	case X86_BUG_OLD_MICROCODE:
+		return old_microcode_show_state(buf);
+
 	default:
 		break;
 	}
@@ -3067,6 +3078,11 @@ ssize_t cpu_show_reg_file_data_sampling(struct device *dev, struct device_attrib
 {
 	return cpu_show_common(dev, attr, buf, X86_BUG_RFDS);
 }
+
+ssize_t cpu_show_old_microcode(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	return cpu_show_common(dev, attr, buf, X86_BUG_OLD_MICROCODE);
+}
 #endif
 
 void __warn_thunk(void)
diff --git a/arch/x86/kernel/cpu/common.c b/arch/x86/kernel/cpu/common.c
index 7cce91b19fb2..8d21887d6666 100644
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -1317,10 +1317,52 @@ static bool __init vulnerable_to_rfds(u64 x86_arch_cap_msr)
 	return cpu_matches(cpu_vuln_blacklist, RFDS);
 }
 
+static struct x86_cpu_id cpu_latest_microcode[] = {
+#include "microcode/intel-ucode-defs.h"
+	{}
+};
+
+static bool __init cpu_has_old_microcode(void)
+{
+	const struct x86_cpu_id *m = x86_match_cpu(cpu_latest_microcode);
+
+	/* Give unknown CPUs a pass: */
+	if (!m) {
+		/* Intel CPUs should be in the list. Warn if not: */
+		if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)
+			pr_info("x86/CPU: Model not found in latest microcode list\n");
+		return false;
+	}
+
+	/*
+	 * Hosts usually lie to guests with a super high microcode
+	 * version. Just ignore what hosts tell guests:
+	 */
+	if (boot_cpu_has(X86_FEATURE_HYPERVISOR))
+		return false;
+
+	/* Consider all debug microcode to be old: */
+	if (boot_cpu_data.microcode & BIT(31))
+		return true;
+
+	/* Give new microocode a pass: */
+	if (boot_cpu_data.microcode >= m->driver_data)
+		return false;
+
+	/* Uh oh, too old: */
+	return true;
+}
+
 static void __init cpu_set_bug_bits(struct cpuinfo_x86 *c)
 {
 	u64 x86_arch_cap_msr = x86_read_arch_cap_msr();
 
+	if (cpu_has_old_microcode()) {
+		pr_warn("x86/CPU: Running old microcode\n");
+		setup_force_cpu_bug(X86_BUG_OLD_MICROCODE);
+		add_taint(TAINT_CPU_OUT_OF_SPEC, LOCKDEP_STILL_OK);
+	}
+
 	/* Set ITLB_MULTIHIT bug if cpu is not in the whitelist and not mitigated */
 	if (!cpu_matches(cpu_vuln_whitelist, NO_ITLB_MULTIHIT) &&
 	    !(x86_arch_cap_msr & ARCH_CAP_PSCHANGE_MC_NO))
diff --git a/arch/x86/kernel/cpu/microcode/intel-ucode-defs.h b/arch/x86/kernel/cpu/microcode/intel-ucode-defs.h
new file mode 100644
index 000000000000..cb6e601701ab
--- /dev/null
+++ b/arch/x86/kernel/cpu/microcode/intel-ucode-defs.h
@@ -0,0 +1,150 @@
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x03, .steppings = 0x0004, .driver_data = 0x2 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x05, .steppings = 0x0001, .driver_data = 0x45 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x05, .steppings = 0x0002, .driver_data = 0x40 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x05, .steppings = 0x0004, .driver_data = 0x2c },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x05, .steppings = 0x0008, .driver_data = 0x10 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x06, .steppings = 0x0001, .driver_data = 0xa },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x06, .steppings = 0x0020, .driver_data = 0x3 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x06, .steppings = 0x0400, .driver_data = 0xd },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x06, .steppings = 0x2000, .driver_data = 0x7 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x07, .steppings = 0x0002, .driver_data = 0x14 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x07, .steppings = 0x0004, .driver_data = 0x38 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x07, .steppings = 0x0008, .driver_data = 0x2e },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x08, .steppings = 0x0002, .driver_data = 0x11 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x08, .steppings = 0x0008, .driver_data = 0x8 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x08, .steppings = 0x0040, .driver_data = 0xc },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x08, .steppings = 0x0400, .driver_data = 0x5 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x09, .steppings = 0x0020, .driver_data = 0x47 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x0a, .steppings = 0x0001, .driver_data = 0x3 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x0a, .steppings = 0x0002, .driver_data = 0x1 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x0b, .steppings = 0x0002, .driver_data = 0x1d },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x0b, .steppings = 0x0010, .driver_data = 0x2 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x0d, .steppings = 0x0040, .driver_data = 0x18 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x0e, .steppings = 0x0100, .driver_data = 0x39 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x0e, .steppings = 0x1000, .driver_data = 0x59 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x0f, .steppings = 0x0004, .driver_data = 0x5d },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x0f, .steppings = 0x0040, .driver_data = 0xd2 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x0f, .steppings = 0x0080, .driver_data = 0x6b },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x0f, .steppings = 0x0400, .driver_data = 0x95 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x0f, .steppings = 0x0800, .driver_data = 0xbc },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x0f, .steppings = 0x2000, .driver_data = 0xa4 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x16, .steppings = 0x0002, .driver_data = 0x44 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x17, .steppings = 0x0040, .driver_data = 0x60f },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x17, .steppings = 0x0080, .driver_data = 0x70a },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x17, .steppings = 0x0400, .driver_data = 0xa0b },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x1a, .steppings = 0x0010, .driver_data = 0x12 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x1a, .steppings = 0x0020, .driver_data = 0x1d },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x1c, .steppings = 0x0004, .driver_data = 0x219 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x1c, .steppings = 0x0400, .driver_data = 0x107 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x1d, .steppings = 0x0002, .driver_data = 0x29 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x1e, .steppings = 0x0020, .driver_data = 0xa },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x25, .steppings = 0x0004, .driver_data = 0x11 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x25, .steppings = 0x0020, .driver_data = 0x7 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x26, .steppings = 0x0002, .driver_data = 0x105 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x2a, .steppings = 0x0080, .driver_data = 0x2f },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x2c, .steppings = 0x0004, .driver_data = 0x1f },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x2d, .steppings = 0x0040, .driver_data = 0x621 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x2d, .steppings = 0x0080, .driver_data = 0x71a },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x2e, .steppings = 0x0040, .driver_data = 0xd },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x2f, .steppings = 0x0004, .driver_data = 0x3b },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x37, .steppings = 0x0100, .driver_data = 0x838 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x37, .steppings = 0x0200, .driver_data = 0x90d },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x3a, .steppings = 0x0200, .driver_data = 0x21 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x3c, .steppings = 0x0008, .driver_data = 0x28 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x3d, .steppings = 0x0010, .driver_data = 0x2f },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x3e, .steppings = 0x0010, .driver_data = 0x42e },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x3e, .steppings = 0x0040, .driver_data = 0x600 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x3e, .steppings = 0x0080, .driver_data = 0x715 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x3f, .steppings = 0x0004, .driver_data = 0x49 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x3f, .steppings = 0x0010, .driver_data = 0x1a },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x45, .steppings = 0x0002, .driver_data = 0x26 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x46, .steppings = 0x0002, .driver_data = 0x1c },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x47, .steppings = 0x0002, .driver_data = 0x22 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x4c, .steppings = 0x0008, .driver_data = 0x368 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x4c, .steppings = 0x0010, .driver_data = 0x411 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x4d, .steppings = 0x0100, .driver_data = 0x12d },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x4e, .steppings = 0x0008, .driver_data = 0xf0 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x55, .steppings = 0x0008, .driver_data = 0x1000191 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x55, .steppings = 0x0010, .driver_data = 0x2007006 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x55, .steppings = 0x0020, .driver_data = 0x3000010 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x55, .steppings = 0x0040, .driver_data = 0x4003605 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x55, .steppings = 0x0080, .driver_data = 0x5003707 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x55, .steppings = 0x0800, .driver_data = 0x7002904 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x56, .steppings = 0x0004, .driver_data = 0x1c },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x56, .steppings = 0x0008, .driver_data = 0x700001c },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x56, .steppings = 0x0010, .driver_data = 0xf00001a },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x56, .steppings = 0x0020, .driver_data = 0xe000015 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x5c, .steppings = 0x0004, .driver_data = 0x14 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x5c, .steppings = 0x0200, .driver_data = 0x48 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x5c, .steppings = 0x0400, .driver_data = 0x28 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x5e, .steppings = 0x0008, .driver_data = 0xf0 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x5f, .steppings = 0x0002, .driver_data = 0x3e },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x66, .steppings = 0x0008, .driver_data = 0x2a },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x6a, .steppings = 0x0020, .driver_data = 0xc0002f0 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x6a, .steppings = 0x0040, .driver_data = 0xd0003e7 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x6c, .steppings = 0x0002, .driver_data = 0x10002b0 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x7a, .steppings = 0x0002, .driver_data = 0x42 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x7a, .steppings = 0x0100, .driver_data = 0x24 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x7e, .steppings = 0x0020, .driver_data = 0xc6 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x8a, .steppings = 0x0002, .driver_data = 0x33 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x8c, .steppings = 0x0002, .driver_data = 0xb8 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x8c, .steppings = 0x0004, .driver_data = 0x38 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x8d, .steppings = 0x0002, .driver_data = 0x52 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x8e, .steppings = 0x0200, .driver_data = 0xf6 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x8e, .steppings = 0x0400, .driver_data = 0xf6 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x8e, .steppings = 0x0800, .driver_data = 0xf6 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x8e, .steppings = 0x1000, .driver_data = 0xfc },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x8f, .steppings = 0x0100, .driver_data = 0x2c000390 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x8f, .steppings = 0x0080, .driver_data = 0x2b000603 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x8f, .steppings = 0x0040, .driver_data = 0x2c000390 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x8f, .steppings = 0x0020, .driver_data = 0x2c000390 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x8f, .steppings = 0x0010, .driver_data = 0x2c000390 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x96, .steppings = 0x0002, .driver_data = 0x1a },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x97, .steppings = 0x0004, .driver_data = 0x37 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x97, .steppings = 0x0020, .driver_data = 0x37 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0xbf, .steppings = 0x0004, .driver_data = 0x37 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0xbf, .steppings = 0x0020, .driver_data = 0x37 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x9a, .steppings = 0x0008, .driver_data = 0x435 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x9a, .steppings = 0x0010, .driver_data = 0x435 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x9c, .steppings = 0x0001, .driver_data = 0x24000026 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x9e, .steppings = 0x0200, .driver_data = 0xf8 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x9e, .steppings = 0x0400, .driver_data = 0xf8 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x9e, .steppings = 0x0800, .driver_data = 0xf6 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x9e, .steppings = 0x1000, .driver_data = 0xf8 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0x9e, .steppings = 0x2000, .driver_data = 0x100 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0xa5, .steppings = 0x0004, .driver_data = 0xfc },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0xa5, .steppings = 0x0008, .driver_data = 0xfc },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0xa5, .steppings = 0x0020, .driver_data = 0xfc },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0xa6, .steppings = 0x0001, .driver_data = 0xfe },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0xa6, .steppings = 0x0002, .driver_data = 0xfc },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0xa7, .steppings = 0x0002, .driver_data = 0x62 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0xaa, .steppings = 0x0010, .driver_data = 0x20 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0xb7, .steppings = 0x0002, .driver_data = 0x12b },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0xba, .steppings = 0x0004, .driver_data = 0x4123 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0xba, .steppings = 0x0008, .driver_data = 0x4123 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0xba, .steppings = 0x0100, .driver_data = 0x4123 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0xbe, .steppings = 0x0001, .driver_data = 0x1a },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0xcf, .steppings = 0x0004, .driver_data = 0x21000283 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0x6,  .model = 0xcf, .steppings = 0x0002, .driver_data = 0x21000283 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0xf,  .model = 0x00, .steppings = 0x0080, .driver_data = 0x12 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0xf,  .model = 0x00, .steppings = 0x0400, .driver_data = 0x15 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0xf,  .model = 0x01, .steppings = 0x0004, .driver_data = 0x2e },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0xf,  .model = 0x02, .steppings = 0x0010, .driver_data = 0x21 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0xf,  .model = 0x02, .steppings = 0x0020, .driver_data = 0x2c },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0xf,  .model = 0x02, .steppings = 0x0040, .driver_data = 0x10 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0xf,  .model = 0x02, .steppings = 0x0080, .driver_data = 0x39 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0xf,  .model = 0x02, .steppings = 0x0200, .driver_data = 0x2f },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0xf,  .model = 0x03, .steppings = 0x0004, .driver_data = 0xa },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0xf,  .model = 0x03, .steppings = 0x0008, .driver_data = 0xc },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0xf,  .model = 0x03, .steppings = 0x0010, .driver_data = 0x17 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0xf,  .model = 0x04, .steppings = 0x0002, .driver_data = 0x17 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0xf,  .model = 0x04, .steppings = 0x0008, .driver_data = 0x5 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0xf,  .model = 0x04, .steppings = 0x0010, .driver_data = 0x6 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0xf,  .model = 0x04, .steppings = 0x0080, .driver_data = 0x3 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0xf,  .model = 0x04, .steppings = 0x0100, .driver_data = 0xe },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0xf,  .model = 0x04, .steppings = 0x0200, .driver_data = 0x3 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0xf,  .model = 0x04, .steppings = 0x0400, .driver_data = 0x4 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0xf,  .model = 0x06, .steppings = 0x0004, .driver_data = 0xf },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0xf,  .model = 0x06, .steppings = 0x0010, .driver_data = 0x4 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0xf,  .model = 0x06, .steppings = 0x0020, .driver_data = 0x8 },
+{ .flags = X86_CPU_ID_FLAG_ENTRY_VALID, .vendor = X86_VENDOR_INTEL, .family = 0xf,  .model = 0x06, .steppings = 0x0100, .driver_data = 0x9 },
diff --git a/arch/x86/tools/insn_decoder_test.c b/arch/x86/tools/insn_decoder_test.c
index 472540aeabc2..6c2986d2ad11 100644
--- a/arch/x86/tools/insn_decoder_test.c
+++ b/arch/x86/tools/insn_decoder_test.c
@@ -10,6 +10,7 @@
 #include <assert.h>
 #include <unistd.h>
 #include <stdarg.h>
+#include <linux/kallsyms.h>
 
 #define unlikely(cond) (cond)
 
@@ -106,7 +107,7 @@ static void parse_args(int argc, char **argv)
 	}
 }
 
-#define BUFSIZE 256
+#define BUFSIZE (256 + KSYM_NAME_LEN)
 
 int main(int argc, char **argv)
 {
diff --git a/crypto/crc32c_generic.c b/crypto/crc32c_generic.c
index 985da981d6e2..99713d0c77c0 100644
--- a/crypto/crc32c_generic.c
+++ b/crypto/crc32c_generic.c
@@ -220,3 +220,4 @@ MODULE_DESCRIPTION("CRC32c (Castagnoli) calculations wrapper for lib/crc32c");
 MODULE_LICENSE("GPL");
 MODULE_ALIAS_CRYPTO("crc32c");
 MODULE_ALIAS_CRYPTO("crc32c-generic");
+MODULE_ALIAS_CRYPTO("crc32c-intel");
diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c
index a7e511849875..1c4359366cd7 100644
--- a/drivers/base/cpu.c
+++ b/drivers/base/cpu.c
@@ -600,6 +600,7 @@ CPU_SHOW_VULN_FALLBACK(spec_rstack_overflow);
 CPU_SHOW_VULN_FALLBACK(gds);
 CPU_SHOW_VULN_FALLBACK(reg_file_data_sampling);
 CPU_SHOW_VULN_FALLBACK(ghostwrite);
+CPU_SHOW_VULN_FALLBACK(old_microcode);
 
 static DEVICE_ATTR(meltdown, 0444, cpu_show_meltdown, NULL);
 static DEVICE_ATTR(spectre_v1, 0444, cpu_show_spectre_v1, NULL);
@@ -616,6 +617,7 @@ static DEVICE_ATTR(spec_rstack_overflow, 0444, cpu_show_spec_rstack_overflow, NU
 static DEVICE_ATTR(gather_data_sampling, 0444, cpu_show_gds, NULL);
 static DEVICE_ATTR(reg_file_data_sampling, 0444, cpu_show_reg_file_data_sampling, NULL);
 static DEVICE_ATTR(ghostwrite, 0444, cpu_show_ghostwrite, NULL);
+static DEVICE_ATTR(old_microcode, 0444, cpu_show_old_microcode, NULL);
 
 static struct attribute *cpu_root_vulnerabilities_attrs[] = {
 	&dev_attr_meltdown.attr,
@@ -633,6 +635,7 @@ static struct attribute *cpu_root_vulnerabilities_attrs[] = {
 	&dev_attr_gather_data_sampling.attr,
 	&dev_attr_reg_file_data_sampling.attr,
 	&dev_attr_ghostwrite.attr,
+	&dev_attr_old_microcode.attr,
 	NULL
 };
 
diff --git a/drivers/gpu/drm/i915/display/intel_dsb.c b/drivers/gpu/drm/i915/display/intel_dsb.c
index e6f8fc743fb4..73f6febfb6c4 100644
--- a/drivers/gpu/drm/i915/display/intel_dsb.c
+++ b/drivers/gpu/drm/i915/display/intel_dsb.c
@@ -763,6 +763,10 @@ struct intel_dsb *intel_dsb_prepare(struct intel_atomic_state *state,
 	if (!i915->display.params.enable_dsb)
 		return NULL;
 
+	/* TODO: DSB is broken in Xe KMD, so disabling it until fixed */
+	if (!IS_ENABLED(I915))
+		return NULL;
+
 	dsb = kzalloc(sizeof(*dsb), GFP_KERNEL);
 	if (!dsb)
 		goto out;
diff --git a/include/linux/cpu.h b/include/linux/cpu.h
index 6a0a8f1c7c90..9532f7039780 100644
--- a/include/linux/cpu.h
+++ b/include/linux/cpu.h
@@ -78,6 +78,8 @@ extern ssize_t cpu_show_gds(struct device *dev,
 extern ssize_t cpu_show_reg_file_data_sampling(struct device *dev,
 					       struct device_attribute *attr, char *buf);
 extern ssize_t cpu_show_ghostwrite(struct device *dev, struct device_attribute *attr, char *buf);
+extern ssize_t cpu_show_old_microcode(struct device *dev,
+				      struct device_attribute *attr, char *buf);
 
 extern __printf(4, 5)
 struct device *cpu_device_create(struct device *parent, void *drvdata,
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 35796c290ca3..a6da7f4411f4 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -2838,6 +2838,15 @@ config FORTIFY_KUNIT_TEST
 	  by the str*() and mem*() family of functions. For testing runtime
 	  traps of FORTIFY_SOURCE, see LKDTM's "FORTIFY_*" tests.
 
+config LONGEST_SYM_KUNIT_TEST
+	tristate "Test the longest symbol possible" if !KUNIT_ALL_TESTS
+	depends on KUNIT && KPROBES
+	default KUNIT_ALL_TESTS
+	help
+	  Tests the longest symbol possible
+
+	  If unsure, say N.
+
 config HW_BREAKPOINT_KUNIT_TEST
 	bool "Test hw_breakpoint constraints accounting" if !KUNIT_ALL_TESTS
 	depends on HAVE_HW_BREAKPOINT
diff --git a/lib/Makefile b/lib/Makefile
index 4f3d00a2fd65..9a54526008d0 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -398,6 +398,8 @@ obj-$(CONFIG_FORTIFY_KUNIT_TEST) += fortify_kunit.o
 obj-$(CONFIG_CRC_KUNIT_TEST) += crc_kunit.o
 obj-$(CONFIG_SIPHASH_KUNIT_TEST) += siphash_kunit.o
 obj-$(CONFIG_USERCOPY_KUNIT_TEST) += usercopy_kunit.o
+obj-$(CONFIG_LONGEST_SYM_KUNIT_TEST) += longest_symbol_kunit.o
+CFLAGS_longest_symbol_kunit.o += $(call cc-disable-warning, missing-prototypes)
 
 obj-$(CONFIG_GENERIC_LIB_DEVMEM_IS_ALLOWED) += devmem_is_allowed.o
 
diff --git a/lib/longest_symbol_kunit.c b/lib/longest_symbol_kunit.c
new file mode 100644
index 000000000000..e3c28ff1807f
--- /dev/null
+++ b/lib/longest_symbol_kunit.c
@@ -0,0 +1,82 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Test the longest symbol length. Execute with:
+ *  ./tools/testing/kunit/kunit.py run longest-symbol
+ *  --arch=x86_64 --kconfig_add CONFIG_KPROBES=y --kconfig_add CONFIG_MODULES=y
+ *  --kconfig_add CONFIG_RETPOLINE=n --kconfig_add CONFIG_CFI_CLANG=n
+ *  --kconfig_add CONFIG_MITIGATION_RETPOLINE=n
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <kunit/test.h>
+#include <linux/stringify.h>
+#include <linux/kprobes.h>
+#include <linux/kallsyms.h>
+
+#define DI(name) s##name##name
+#define DDI(name) DI(n##name##name)
+#define DDDI(name) DDI(n##name##name)
+#define DDDDI(name) DDDI(n##name##name)
+#define DDDDDI(name) DDDDI(n##name##name)
+
+/*Generate a symbol whose name length is 511 */
+#define LONGEST_SYM_NAME  DDDDDI(g1h2i3j4k5l6m7n)
+
+#define RETURN_LONGEST_SYM 0xAAAAA
+
+noinline int LONGEST_SYM_NAME(void);
+noinline int LONGEST_SYM_NAME(void)
+{
+	return RETURN_LONGEST_SYM;
+}
+
+_Static_assert(sizeof(__stringify(LONGEST_SYM_NAME)) == KSYM_NAME_LEN,
+"Incorrect symbol length found. Expected KSYM_NAME_LEN: "
+__stringify(KSYM_NAME_LEN) ", but found: "
+__stringify(sizeof(LONGEST_SYM_NAME)));
+
+static void test_longest_symbol(struct kunit *test)
+{
+	KUNIT_EXPECT_EQ(test, RETURN_LONGEST_SYM, LONGEST_SYM_NAME());
+};
+
+static void test_longest_symbol_kallsyms(struct kunit *test)
+{
+	unsigned long (*kallsyms_lookup_name)(const char *name);
+	static int (*longest_sym)(void);
+
+	struct kprobe kp = {
+		.symbol_name = "kallsyms_lookup_name",
+	};
+
+	if (register_kprobe(&kp) < 0) {
+		pr_info("%s: kprobe not registered", __func__);
+		KUNIT_FAIL(test, "test_longest_symbol kallsyms: kprobe not registered\n");
+		return;
+	}
+
+	kunit_warn(test, "test_longest_symbol kallsyms: kprobe registered\n");
+	kallsyms_lookup_name = (unsigned long (*)(const char *name))kp.addr;
+	unregister_kprobe(&kp);
+
+	longest_sym =
+		(void *) kallsyms_lookup_name(__stringify(LONGEST_SYM_NAME));
+	KUNIT_EXPECT_EQ(test, RETURN_LONGEST_SYM, longest_sym());
+};
+
+static struct kunit_case longest_symbol_test_cases[] = {
+	KUNIT_CASE(test_longest_symbol),
+	KUNIT_CASE(test_longest_symbol_kallsyms),
+	{}
+};
+
+static struct kunit_suite longest_symbol_test_suite = {
+	.name = "longest-symbol",
+	.test_cases = longest_symbol_test_cases,
+};
+kunit_test_suite(longest_symbol_test_suite);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Test the longest symbol length");
+MODULE_AUTHOR("Sergio González Collado");
diff --git a/scripts/package/PKGBUILD b/scripts/package/PKGBUILD
index 0cf3a55b05e1..a27d4344a4e8 100644
--- a/scripts/package/PKGBUILD
+++ b/scripts/package/PKGBUILD
@@ -90,6 +90,11 @@ _package-headers() {
 		"${srctree}/scripts/package/install-extmod-build" "${builddir}"
 	fi
 
+	# required when DEBUG_INFO_BTF_MODULES is enabled
+	if [ -f tools/bpf/resolve_btfids/resolve_btfids ]; then
+		install -Dt "$builddir/tools/bpf/resolve_btfids" tools/bpf/resolve_btfids/resolve_btfids
+	fi
+
 	echo "Installing System.map and config..."
 	mkdir -p "${builddir}"
 	cp System.map "${builddir}/System.map"
-- 
2.49.0.391.g4bbb303af6