The patchset adds bits and pieces to get kexec (and crashkernel) work on TDX guest.
The last patch implements CPU offlining according to the approved ACPI spec change poposal[1]. It unlocks kexec with all CPUs visible in the target kernel. It requires BIOS-side enabling. If it missing we fallback to booting 2nd kernel with single CPU. Please review. I would be glad for any feedback. [1] https://lore.kernel.org/all/13356251.uLZWGnKmhe@kreacher v12: - Drop 'crash' argument from x86_guest::enc_kexec_begin(); - Rework CR4 setting in identity_mapped(); - Fix comments and commit message. - Add review tags; v11: - Rebased onto current tip/master; - Rename CONFIG_X86_ACPI_MADT_WAKEUP to CONFIG_ACPI_MADT_WAKEUP; - Drop CC_ATTR_GUEST_MEM_ENCRYPT checks around x86_platform.guest.enc_kexec_* callbacks; - Rename x86_platform.guest.enc_kexec_* callbacks; - Report error code in case of vmm call fail in __set_memory_enc_pgtable(); - Update commit messages and comments; - Add Reviewed-bys; v10: - Rebased to current tip/master; - Preserve CR4.MCE instead of setting it unconditionally; - Fix build error in Hyper-V code after rebase; - Include Ashish's patch for real; v9: - Rebased; - Keep page tables that maps E820_TYPE_ACPI (Ashish); - Ack/Reviewed/Tested-bys from Sathya, Kai, Tao; - Minor printk() message adjustments; v8: - Rework serialization of around conversion memory back to private; - Print ACPI_MADT_TYPE_MULTIPROC_WAKEUP in acpi_table_print_madt_entry(); - Drop debugfs interface to dump info on shared memory; - Adjust comments and commit messages; - Reviewed-bys by Baoquan, Dave and Thomas; v7: - Call enc_kexec_stop_conversion() and enc_kexec_unshare_mem() after shutting down IO-APIC, lapic and hpet. It meets AMD requirements. - Minor style changes; - Add Acked/Reviewed-bys; v6: - Rebased to v6.8-rc1; - Provide default noop callbacks from .enc_kexec_stop_conversion and .enc_kexec_unshare_mem; - Split off patch that introduces .enc_kexec_* callbacks; - asm_acpi_mp_play_dead(): program CR3 directly from RSI, no MOV to RAX required; - Restructure how smp_ops.stop_this_cpu() hooked up in crash_nmi_callback(); - kvmclock patch got merged via KVM tree; v5: - Rename smp_ops.crash_play_dead to smp_ops.stop_this_cpu and use it in stop_this_cpu(); - Split off enc_kexec_stop_conversion() from enc_kexec_unshare_mem(); - Introduce kernel_ident_mapping_free(); - Add explicit include for alternatives and stringify. - Add barrier() after setting conversion_allowed to false; - Mark cpu_hotplug_offline_disabled __ro_after_init; - Print error if failed to hand over CPU to BIOS; - Update comments and commit messages; v4: - Fix build for !KEXEC_CORE; - Cleaner ATLERNATIVE use; - Update commit messages and comments; - Add Reviewed-bys; v3: - Rework acpi_mp_crash_stop_other_cpus() to avoid invoking hotplug state machine; - Free page tables if reset vector setup failed; - Change asm_acpi_mp_play_dead() to pass reset vector and PGD as arguments; - Mark acpi_mp_* variables as static and __ro_after_init; - Use u32 for apicid; - Disable CPU offlining if reset vector setup failed; - Rename madt.S -> madt_playdead.S; - Mark tdx_kexec_unshare_mem() as static; - Rebase onto up-to-date tip/master; - Whitespace fixes; - Reorder patches; - Add Reviewed-bys; - Update comments and commit messages; v2: - Rework how unsharing hook ups into kexec codepath; - Rework kvmclock_disable() fix based on Sean's; - s/cpu_hotplug_not_supported()/cpu_hotplug_disable_offlining()/; - use play_dead_common() to implement acpi_mp_play_dead(); - cond_resched() in tdx_shared_memory_show(); - s/target kernel/second kernel/; - Update commit messages and comments; Ashish Kalra (1): x86/mm: Do not zap page table entries mapping unaccepted memory table during kdump. Borislav Petkov (1): x86/relocate_kernel: Use named labels for less confusion Kirill A. Shutemov (17): x86/acpi: Extract ACPI MADT wakeup code into a separate file x86/apic: Mark acpi_mp_wake_* variables as __ro_after_init cpu/hotplug: Add support for declaring CPU offlining not supported cpu/hotplug, x86/acpi: Disable CPU offlining for ACPI MADT wakeup x86/kexec: Keep CR4.MCE set during kexec for TDX guest x86/mm: Make x86_platform.guest.enc_status_change_*() return errno x86/mm: Return correct level from lookup_address() if pte is none x86/tdx: Account shared memory x86/mm: Add callbacks to prepare encrypted memory for kexec x86/tdx: Convert shared memory back to private on kexec x86/mm: Make e820__end_ram_pfn() cover E820_TYPE_ACPI ranges x86/acpi: Rename fields in acpi_madt_multiproc_wakeup structure x86/acpi: Do not attempt to bring up secondary CPUs in kexec case x86/smp: Add smp_ops.stop_this_cpu() callback x86/mm: Introduce kernel_ident_mapping_free() x86/acpi: Add support for CPU offlining for ACPI MADT wakeup method ACPI: tables: Print MULTIPROC_WAKEUP when MADT is parsed arch/x86/Kconfig | 7 + arch/x86/coco/core.c | 1 - arch/x86/coco/tdx/tdx.c | 121 ++++++++++- arch/x86/hyperv/ivm.c | 22 +- arch/x86/include/asm/acpi.h | 7 + arch/x86/include/asm/init.h | 3 + arch/x86/include/asm/pgtable.h | 5 + arch/x86/include/asm/pgtable_types.h | 1 + arch/x86/include/asm/set_memory.h | 3 + arch/x86/include/asm/smp.h | 1 + arch/x86/include/asm/x86_init.h | 14 +- arch/x86/kernel/acpi/Makefile | 1 + arch/x86/kernel/acpi/boot.c | 86 +------- arch/x86/kernel/acpi/madt_playdead.S | 28 +++ arch/x86/kernel/acpi/madt_wakeup.c | 292 +++++++++++++++++++++++++++ arch/x86/kernel/crash.c | 12 ++ arch/x86/kernel/e820.c | 9 +- arch/x86/kernel/process.c | 7 + arch/x86/kernel/reboot.c | 18 ++ arch/x86/kernel/relocate_kernel_64.S | 24 ++- arch/x86/kernel/x86_init.c | 8 +- arch/x86/mm/ident_map.c | 73 +++++++ arch/x86/mm/init_64.c | 16 +- arch/x86/mm/mem_encrypt_amd.c | 8 +- arch/x86/mm/pat/set_memory.c | 75 +++++-- drivers/acpi/tables.c | 14 ++ include/acpi/actbl2.h | 19 +- include/linux/cc_platform.h | 10 - include/linux/cpuhplock.h | 2 + kernel/cpu.c | 12 +- 30 files changed, 733 insertions(+), 166 deletions(-) create mode 100644 arch/x86/kernel/acpi/madt_playdead.S create mode 100644 arch/x86/kernel/acpi/madt_wakeup.c -- 2.43.0
