[PATCHv11 00/19] x86/tdx: Add kexec support
From: Kirill A. Shutemov
Date: Tue May 28 2024 - 05:55:48 EST
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
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 | 96 ++++++++-
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 | 13 +-
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 | 25 ++-
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 | 74 +++++--
drivers/acpi/tables.c | 14 ++
include/acpi/actbl2.h | 19 +-
include/linux/cc_platform.h | 10 -
include/linux/cpu.h | 2 +
kernel/cpu.c | 12 +-
30 files changed, 707 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