mirror of
https://github.com/torvalds/linux.git
synced 2026-04-28 11:32:28 -04:00
69e23faf82
Intel TDX protects guest VM's from malicious host and certain physical attacks. TDX introduces a new operation mode, Secure Arbitration Mode (SEAM) to isolate and protect guest VM's. A TDX guest VM runs in SEAM and, unlike VMX, direct control and interaction with the guest by the host VMM is not possible. Instead, Intel TDX Module, which also runs in SEAM, provides a SEAMCALL API. The SEAMCALL that provides the ability to enter a guest is TDH.VP.ENTER. The TDX Module processes TDH.VP.ENTER, and enters the guest via VMX VMLAUNCH/VMRESUME instructions. When a guest VM-exit requires host VMM interaction, the TDH.VP.ENTER SEAMCALL returns to the host VMM (KVM). Add tdh_vp_enter() to wrap the SEAMCALL invocation of TDH.VP.ENTER; tdh_vp_enter() needs to be noinstr because VM entry in KVM is noinstr as well, which is for two reasons: * marking the area as CT_STATE_GUEST via guest_state_enter_irqoff() and guest_state_exit_irqoff() * IRET must be avoided between VM-exit and NMI handling, in order to avoid prematurely releasing the NMI inhibit. TDH.VP.ENTER is different from other SEAMCALLs in several ways: it uses more arguments, and after it returns some host state may need to be restored. Therefore tdh_vp_enter() uses __seamcall_saved_ret() instead of __seamcall_ret(); since it is the only caller of __seamcall_saved_ret(), it can be made noinstr also. TDH.VP.ENTER arguments are passed through General Purpose Registers (GPRs). For the special case of the TD guest invoking TDG.VP.VMCALL, nearly any GPR can be used, as well as XMM0 to XMM15. Notably, RBP is not used, and Linux mandates the TDX Module feature NO_RBP_MOD, which is enforced elsewhere. Additionally, XMM registers are not required for the existing Guest Hypervisor Communication Interface and are handled by existing KVM code should they be modified by the guest. There are 2 input formats and 5 output formats for TDH.VP.ENTER arguments. Input #1 : Initial entry or following a previous async. TD Exit Input #2 : Following a previous TDCALL(TDG.VP.VMCALL) Output #1 : On Error (No TD Entry) Output #2 : Async. Exits with a VMX Architectural Exit Reason Output #3 : Async. Exits with a non-VMX TD Exit Status Output #4 : Async. Exits with Cross-TD Exit Details Output #5 : On TDCALL(TDG.VP.VMCALL) Currently, to keep things simple, the wrapper function does not attempt to support different formats, and just passes all the GPRs that could be used. The GPR values are held by KVM in the area set aside for guest GPRs. KVM code uses the guest GPR area (vcpu->arch.regs[]) to set up for or process results of tdh_vp_enter(). Therefore changing tdh_vp_enter() to use more complex argument formats would also alter the way KVM code interacts with tdh_vp_enter(). Signed-off-by: Kai Huang <kai.huang@intel.com> Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Message-ID: <20241121201448.36170-2-adrian.hunter@intel.com> Acked-by: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
122 lines
2.9 KiB
C
122 lines
2.9 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef _X86_VIRT_TDX_H
|
|
#define _X86_VIRT_TDX_H
|
|
|
|
#include <linux/bits.h>
|
|
|
|
/*
|
|
* This file contains both macros and data structures defined by the TDX
|
|
* architecture and Linux defined software data structures and functions.
|
|
* The two should not be mixed together for better readability. The
|
|
* architectural definitions come first.
|
|
*/
|
|
|
|
/*
|
|
* TDX module SEAMCALL leaf functions
|
|
*/
|
|
#define TDH_VP_ENTER 0
|
|
#define TDH_MNG_ADDCX 1
|
|
#define TDH_MEM_PAGE_ADD 2
|
|
#define TDH_MEM_SEPT_ADD 3
|
|
#define TDH_VP_ADDCX 4
|
|
#define TDH_MEM_PAGE_AUG 6
|
|
#define TDH_MEM_RANGE_BLOCK 7
|
|
#define TDH_MNG_KEY_CONFIG 8
|
|
#define TDH_MNG_CREATE 9
|
|
#define TDH_MNG_RD 11
|
|
#define TDH_MR_EXTEND 16
|
|
#define TDH_MR_FINALIZE 17
|
|
#define TDH_VP_FLUSH 18
|
|
#define TDH_MNG_VPFLUSHDONE 19
|
|
#define TDH_VP_CREATE 10
|
|
#define TDH_MNG_KEY_FREEID 20
|
|
#define TDH_MNG_INIT 21
|
|
#define TDH_VP_INIT 22
|
|
#define TDH_PHYMEM_PAGE_RDMD 24
|
|
#define TDH_VP_RD 26
|
|
#define TDH_PHYMEM_PAGE_RECLAIM 28
|
|
#define TDH_MEM_PAGE_REMOVE 29
|
|
#define TDH_SYS_KEY_CONFIG 31
|
|
#define TDH_SYS_INIT 33
|
|
#define TDH_SYS_RD 34
|
|
#define TDH_SYS_LP_INIT 35
|
|
#define TDH_SYS_TDMR_INIT 36
|
|
#define TDH_MEM_TRACK 38
|
|
#define TDH_PHYMEM_CACHE_WB 40
|
|
#define TDH_PHYMEM_PAGE_WBINVD 41
|
|
#define TDH_VP_WR 43
|
|
#define TDH_SYS_CONFIG 45
|
|
|
|
/*
|
|
* SEAMCALL leaf:
|
|
*
|
|
* Bit 15:0 Leaf number
|
|
* Bit 23:16 Version number
|
|
*/
|
|
#define TDX_VERSION_SHIFT 16
|
|
|
|
/* TDX page types */
|
|
#define PT_NDA 0x0
|
|
#define PT_RSVD 0x1
|
|
|
|
struct tdmr_reserved_area {
|
|
u64 offset;
|
|
u64 size;
|
|
} __packed;
|
|
|
|
#define TDMR_INFO_ALIGNMENT 512
|
|
#define TDMR_INFO_PA_ARRAY_ALIGNMENT 512
|
|
|
|
struct tdmr_info {
|
|
u64 base;
|
|
u64 size;
|
|
u64 pamt_1g_base;
|
|
u64 pamt_1g_size;
|
|
u64 pamt_2m_base;
|
|
u64 pamt_2m_size;
|
|
u64 pamt_4k_base;
|
|
u64 pamt_4k_size;
|
|
/*
|
|
* The actual number of reserved areas depends on the value of
|
|
* field MD_FIELD_ID_MAX_RESERVED_PER_TDMR in the TDX module
|
|
* global metadata.
|
|
*/
|
|
DECLARE_FLEX_ARRAY(struct tdmr_reserved_area, reserved_areas);
|
|
} __packed __aligned(TDMR_INFO_ALIGNMENT);
|
|
|
|
/* Bit definitions of TDX_FEATURES0 metadata field */
|
|
#define TDX_FEATURES0_NO_RBP_MOD BIT(18)
|
|
|
|
/*
|
|
* Do not put any hardware-defined TDX structure representations below
|
|
* this comment!
|
|
*/
|
|
|
|
/* Kernel defined TDX module status during module initialization. */
|
|
enum tdx_module_status_t {
|
|
TDX_MODULE_UNINITIALIZED,
|
|
TDX_MODULE_INITIALIZED,
|
|
TDX_MODULE_ERROR
|
|
};
|
|
|
|
struct tdx_memblock {
|
|
struct list_head list;
|
|
unsigned long start_pfn;
|
|
unsigned long end_pfn;
|
|
int nid;
|
|
};
|
|
|
|
/* Warn if kernel has less than TDMR_NR_WARN TDMRs after allocation */
|
|
#define TDMR_NR_WARN 4
|
|
|
|
struct tdmr_info_list {
|
|
void *tdmrs; /* Flexible array to hold 'tdmr_info's */
|
|
int nr_consumed_tdmrs; /* How many 'tdmr_info's are in use */
|
|
|
|
/* Metadata for finding target 'tdmr_info' and freeing @tdmrs */
|
|
int tdmr_sz; /* Size of one 'tdmr_info' */
|
|
int max_tdmrs; /* How many 'tdmr_info's are allocated */
|
|
};
|
|
|
|
#endif
|