Merge tag 'x86_cc_for_v6.11_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 confidential computing updates from Borislav Petkov:
 "Unrelated x86/cc changes queued here to avoid ugly cross-merges and
  conflicts:

   - Carve out CPU hotplug function declarations into a separate header
     with the goal to be able to use the lockdep assertions in a more
     flexible manner

   - As a result, refactor cacheinfo code after carving out a function
     to return the cache ID associated with a given cache level

   - Cleanups

  Add support to be able to kexec TDX guests:

   - Expand ACPI MADT CPU offlining support

   - Add machinery to prepare CoCo guests memory before kexec-ing into a
     new kernel

   - Cleanup, readjust and massage related code"

* tag 'x86_cc_for_v6.11_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
  ACPI: tables: Print MULTIPROC_WAKEUP when MADT is parsed
  x86/acpi: Add support for CPU offlining for ACPI MADT wakeup method
  x86/mm: Introduce kernel_ident_mapping_free()
  x86/smp: Add smp_ops.stop_this_cpu() callback
  x86/acpi: Do not attempt to bring up secondary CPUs in the kexec case
  x86/acpi: Rename fields in the acpi_madt_multiproc_wakeup structure
  x86/mm: Do not zap page table entries mapping unaccepted memory table during kdump
  x86/mm: Make e820__end_ram_pfn() cover E820_TYPE_ACPI ranges
  x86/tdx: Convert shared memory back to private on kexec
  x86/mm: Add callbacks to prepare encrypted memory for kexec
  x86/tdx: Account shared memory
  x86/mm: Return correct level from lookup_address() if pte is none
  x86/mm: Make x86_platform.guest.enc_status_change_*() return an error
  x86/kexec: Keep CR4.MCE set during kexec for TDX guest
  x86/relocate_kernel: Use named labels for less confusion
  cpu/hotplug, x86/acpi: Disable CPU offlining for ACPI MADT wakeup
  cpu/hotplug: Add support for declaring CPU offlining not supported
  x86/apic: Mark acpi_mp_wake_* variables as __ro_after_init
  x86/acpi: Extract ACPI MADT wakeup code into a separate file
  x86/kexec: Remove spurious unconditional JMP from from identity_mapped()
  ...

5 files changed, 86 insertions, 50 deletions

diff --git a/include/acpi/actbl2.h b/include/acpi/actbl2.h
index ae747c89d92c..e27958ef8264 100644
--- a/include/acpi/actbl2.h
+++ b/include/acpi/actbl2.h
@@ -1194,11 +1194,23 @@ struct acpi_madt_generic_translator {
 
 struct acpi_madt_multiproc_wakeup {
 	struct acpi_subtable_header header;
-	u16 mailbox_version;
+	u16 version;
 	u32 reserved;		/* reserved - must be zero */
-	u64 base_address;
+	u64 mailbox_address;
+	u64 reset_vector;
 };
 
+/* Values for Version field above */
+
+enum acpi_madt_multiproc_wakeup_version {
+	ACPI_MADT_MP_WAKEUP_VERSION_NONE = 0,
+	ACPI_MADT_MP_WAKEUP_VERSION_V1 = 1,
+	ACPI_MADT_MP_WAKEUP_VERSION_RESERVED = 2, /* 2 and greater are reserved */
+};
+
+#define ACPI_MADT_MP_WAKEUP_SIZE_V0	16
+#define ACPI_MADT_MP_WAKEUP_SIZE_V1	24
+
 #define ACPI_MULTIPROC_WAKEUP_MB_OS_SIZE        2032
 #define ACPI_MULTIPROC_WAKEUP_MB_FIRMWARE_SIZE  2048
 
@@ -1211,7 +1223,8 @@ struct acpi_madt_multiproc_wakeup_mailbox {
 	u8 reserved_firmware[ACPI_MULTIPROC_WAKEUP_MB_FIRMWARE_SIZE];	/* reserved for firmware use */
 };
 
-#define ACPI_MP_WAKE_COMMAND_WAKEUP    1
+#define ACPI_MP_WAKE_COMMAND_WAKEUP	1
+#define ACPI_MP_WAKE_COMMAND_TEST	2
 
 /* 17: CPU Core Interrupt Controller (ACPI 6.5) */
 
diff --git a/include/linux/cacheinfo.h b/include/linux/cacheinfo.h
index 2cb15fe4fe12..3dde175f4108 100644
--- a/include/linux/cacheinfo.h
+++ b/include/linux/cacheinfo.h
@@ -3,6 +3,7 @@
 #define _LINUX_CACHEINFO_H
 
 #include <linux/bitops.h>
+#include <linux/cpuhplock.h>
 #include <linux/cpumask.h>
 #include <linux/smp.h>
 
@@ -113,23 +114,37 @@ int acpi_get_cache_info(unsigned int cpu,
 const struct attribute_group *cache_get_priv_group(struct cacheinfo *this_leaf);
 
 /*
- * Get the id of the cache associated with @cpu at level @level.
+ * Get the cacheinfo structure for the cache associated with @cpu at
+ * level @level.
  * cpuhp lock must be held.
  */
-static inline int get_cpu_cacheinfo_id(int cpu, int level)
+static inline struct cacheinfo *get_cpu_cacheinfo_level(int cpu, int level)
 {
 	struct cpu_cacheinfo *ci = get_cpu_cacheinfo(cpu);
 	int i;
 
+	lockdep_assert_cpus_held();
+
 	for (i = 0; i < ci->num_leaves; i++) {
 		if (ci->info_list[i].level == level) {
 			if (ci->info_list[i].attributes & CACHE_ID)
-				return ci->info_list[i].id;
-			return -1;
+				return &ci->info_list[i];
+			return NULL;
 		}
 	}
 
-	return -1;
+	return NULL;
+}
+
+/*
+ * Get the id of the cache associated with @cpu at level @level.
+ * cpuhp lock must be held.
+ */
+static inline int get_cpu_cacheinfo_id(int cpu, int level)
+{
+	struct cacheinfo *ci = get_cpu_cacheinfo_level(cpu, level);
+
+	return ci ? ci->id : -1;
 }
 
 #ifdef CONFIG_ARM64
diff --git a/include/linux/cc_platform.h b/include/linux/cc_platform.h
index 60693a145894..caa4b4430634 100644
--- a/include/linux/cc_platform.h
+++ b/include/linux/cc_platform.h
@@ -82,16 +82,6 @@ enum cc_attr {
 	CC_ATTR_GUEST_SEV_SNP,
 
 	/**
-	 * @CC_ATTR_HOTPLUG_DISABLED: Hotplug is not supported or disabled.
-	 *
-	 * The platform/OS is running as a guest/virtual machine does not
-	 * support CPU hotplug feature.
-	 *
-	 * Examples include TDX Guest.
-	 */
-	CC_ATTR_HOTPLUG_DISABLED,
-
-	/**
 	 * @CC_ATTR_HOST_SEV_SNP: AMD SNP enabled on the host.
 	 *
 	 * The host kernel is running with the necessary features
diff --git a/include/linux/cpu.h b/include/linux/cpu.h
index 861c3bfc5f17..a8926d0a28cd 100644
--- a/include/linux/cpu.h
+++ b/include/linux/cpu.h
@@ -18,6 +18,7 @@
 #include <linux/compiler.h>
 #include <linux/cpumask.h>
 #include <linux/cpuhotplug.h>
+#include <linux/cpuhplock.h>
 #include <linux/cpu_smt.h>
 
 struct device;
@@ -132,38 +133,6 @@ static inline int add_cpu(unsigned int cpu) { return 0;}
 #endif /* CONFIG_SMP */
 extern const struct bus_type cpu_subsys;
 
-extern int lockdep_is_cpus_held(void);
-
-#ifdef CONFIG_HOTPLUG_CPU
-extern void cpus_write_lock(void);
-extern void cpus_write_unlock(void);
-extern void cpus_read_lock(void);
-extern void cpus_read_unlock(void);
-extern int  cpus_read_trylock(void);
-extern void lockdep_assert_cpus_held(void);
-extern void cpu_hotplug_disable(void);
-extern void cpu_hotplug_enable(void);
-void clear_tasks_mm_cpumask(int cpu);
-int remove_cpu(unsigned int cpu);
-int cpu_device_down(struct device *dev);
-extern void smp_shutdown_nonboot_cpus(unsigned int primary_cpu);
-
-#else /* CONFIG_HOTPLUG_CPU */
-
-static inline void cpus_write_lock(void) { }
-static inline void cpus_write_unlock(void) { }
-static inline void cpus_read_lock(void) { }
-static inline void cpus_read_unlock(void) { }
-static inline int  cpus_read_trylock(void) { return true; }
-static inline void lockdep_assert_cpus_held(void) { }
-static inline void cpu_hotplug_disable(void) { }
-static inline void cpu_hotplug_enable(void) { }
-static inline int remove_cpu(unsigned int cpu) { return -EPERM; }
-static inline void smp_shutdown_nonboot_cpus(unsigned int primary_cpu) { }
-#endif	/* !CONFIG_HOTPLUG_CPU */
-
-DEFINE_LOCK_GUARD_0(cpus_read_lock, cpus_read_lock(), cpus_read_unlock())
-
 #ifdef CONFIG_PM_SLEEP_SMP
 extern int freeze_secondary_cpus(int primary);
 extern void thaw_secondary_cpus(void);
diff --git a/include/linux/cpuhplock.h b/include/linux/cpuhplock.h
new file mode 100644
index 000000000000..f7aa20f62b87
--- /dev/null
+++ b/include/linux/cpuhplock.h
@@ -0,0 +1,49 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * include/linux/cpuhplock.h - CPU hotplug locking
+ *
+ * Locking functions for CPU hotplug.
+ */
+#ifndef _LINUX_CPUHPLOCK_H_
+#define _LINUX_CPUHPLOCK_H_
+
+#include <linux/cleanup.h>
+#include <linux/errno.h>
+
+struct device;
+
+extern int lockdep_is_cpus_held(void);
+
+#ifdef CONFIG_HOTPLUG_CPU
+void cpus_write_lock(void);
+void cpus_write_unlock(void);
+void cpus_read_lock(void);
+void cpus_read_unlock(void);
+int  cpus_read_trylock(void);
+void lockdep_assert_cpus_held(void);
+void cpu_hotplug_disable_offlining(void);
+void cpu_hotplug_disable(void);
+void cpu_hotplug_enable(void);
+void clear_tasks_mm_cpumask(int cpu);
+int remove_cpu(unsigned int cpu);
+int cpu_device_down(struct device *dev);
+void smp_shutdown_nonboot_cpus(unsigned int primary_cpu);
+
+#else /* CONFIG_HOTPLUG_CPU */
+
+static inline void cpus_write_lock(void) { }
+static inline void cpus_write_unlock(void) { }
+static inline void cpus_read_lock(void) { }
+static inline void cpus_read_unlock(void) { }
+static inline int  cpus_read_trylock(void) { return true; }
+static inline void lockdep_assert_cpus_held(void) { }
+static inline void cpu_hotplug_disable_offlining(void) { }
+static inline void cpu_hotplug_disable(void) { }
+static inline void cpu_hotplug_enable(void) { }
+static inline int remove_cpu(unsigned int cpu) { return -EPERM; }
+static inline void smp_shutdown_nonboot_cpus(unsigned int primary_cpu) { }
+#endif	/* !CONFIG_HOTPLUG_CPU */
+
+DEFINE_LOCK_GUARD_0(cpus_read_lock, cpus_read_lock(), cpus_read_unlock())
+
+#endif /* _LINUX_CPUHPLOCK_H_ */