- Fixup comment typo
- Prevent unexpected #VE's from:
- Hosts removing perfectly good guest mappings (SEPT_VE_DISABLE
- Excessive #VE notifications (NOTIFY_ENABLES) which are
delivered via a #VE.
-----BEGIN PGP SIGNATURE-----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=UpyL
-----END PGP SIGNATURE-----
Merge tag 'x86_tdx_for_6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull Intel Trust Domain Extensions (TDX) updates from Dave Hansen:
"Other than a minor fixup, the content here is to ensure that TDX
guests never see virtualization exceptions (#VE's) that might be
induced by the untrusted VMM.
This is a highly desirable property. Without it, #VE exception
handling would fall somewhere between NMIs, machine checks and total
insanity. With it, #VE handling remains pretty mundane.
Summary:
- Fixup comment typo
- Prevent unexpected #VE's from:
- Hosts removing perfectly good guest mappings (SEPT_VE_DISABLE)
- Excessive #VE notifications (NOTIFY_ENABLES) which are delivered
via a #VE"
* tag 'x86_tdx_for_6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/tdx: Do not corrupt frame-pointer in __tdx_hypercall()
x86/tdx: Disable NOTIFY_ENABLES
x86/tdx: Relax SEPT_VE_DISABLE check for debug TD
x86/tdx: Use ReportFatalError to report missing SEPT_VE_DISABLE
x86/tdx: Expand __tdx_hypercall() to handle more arguments
x86/tdx: Refactor __tdx_hypercall() to allow pass down more arguments
x86/tdx: Add more registers to struct tdx_hypercall_args
x86/tdx: Fix typo in comment in __tdx_hypercall()
This commit is contained in:
Linus Torvalds
commit
d8e473182a
@ -13,6 +13,12 @@
|
||||
/*
|
||||
* Bitmasks of exposed registers (with VMM).
|
||||
*/
|
||||
#define TDX_RDX BIT(2)
|
||||
#define TDX_RBX BIT(3)
|
||||
#define TDX_RSI BIT(6)
|
||||
#define TDX_RDI BIT(7)
|
||||
#define TDX_R8 BIT(8)
|
||||
#define TDX_R9 BIT(9)
|
||||
#define TDX_R10 BIT(10)
|
||||
#define TDX_R11 BIT(11)
|
||||
#define TDX_R12 BIT(12)
|
||||
@ -27,9 +33,9 @@
|
||||
* details can be found in TDX GHCI specification, section
|
||||
* titled "TDCALL [TDG.VP.VMCALL] leaf".
|
||||
*/
|
||||
#define TDVMCALL_EXPOSE_REGS_MASK ( TDX_R10 | TDX_R11 | \
|
||||
TDX_R12 | TDX_R13 | \
|
||||
TDX_R14 | TDX_R15 )
|
||||
#define TDVMCALL_EXPOSE_REGS_MASK \
|
||||
( TDX_RDX | TDX_RBX | TDX_RSI | TDX_RDI | TDX_R8 | TDX_R9 | \
|
||||
TDX_R10 | TDX_R11 | TDX_R12 | TDX_R13 | TDX_R14 | TDX_R15 )
|
||||
|
||||
.section .noinstr.text, "ax"
|
||||
|
||||
@ -126,25 +132,38 @@ SYM_FUNC_START(__tdx_hypercall)
|
||||
push %r14
|
||||
push %r13
|
||||
push %r12
|
||||
push %rbx
|
||||
|
||||
/* Free RDI and RSI to be used as TDVMCALL arguments */
|
||||
movq %rdi, %rax
|
||||
push %rsi
|
||||
|
||||
/* Copy hypercall registers from arg struct: */
|
||||
movq TDX_HYPERCALL_r8(%rax), %r8
|
||||
movq TDX_HYPERCALL_r9(%rax), %r9
|
||||
movq TDX_HYPERCALL_r10(%rax), %r10
|
||||
movq TDX_HYPERCALL_r11(%rax), %r11
|
||||
movq TDX_HYPERCALL_r12(%rax), %r12
|
||||
movq TDX_HYPERCALL_r13(%rax), %r13
|
||||
movq TDX_HYPERCALL_r14(%rax), %r14
|
||||
movq TDX_HYPERCALL_r15(%rax), %r15
|
||||
movq TDX_HYPERCALL_rdi(%rax), %rdi
|
||||
movq TDX_HYPERCALL_rsi(%rax), %rsi
|
||||
movq TDX_HYPERCALL_rbx(%rax), %rbx
|
||||
movq TDX_HYPERCALL_rdx(%rax), %rdx
|
||||
|
||||
push %rax
|
||||
|
||||
/* Mangle function call ABI into TDCALL ABI: */
|
||||
/* Set TDCALL leaf ID (TDVMCALL (0)) in RAX */
|
||||
xor %eax, %eax
|
||||
|
||||
/* Copy hypercall registers from arg struct: */
|
||||
movq TDX_HYPERCALL_r10(%rdi), %r10
|
||||
movq TDX_HYPERCALL_r11(%rdi), %r11
|
||||
movq TDX_HYPERCALL_r12(%rdi), %r12
|
||||
movq TDX_HYPERCALL_r13(%rdi), %r13
|
||||
movq TDX_HYPERCALL_r14(%rdi), %r14
|
||||
movq TDX_HYPERCALL_r15(%rdi), %r15
|
||||
|
||||
movl $TDVMCALL_EXPOSE_REGS_MASK, %ecx
|
||||
|
||||
tdcall
|
||||
|
||||
/*
|
||||
* RAX==0 indicates a failure of the TDVMCALL mechanism itself and that
|
||||
* RAX!=0 indicates a failure of the TDVMCALL mechanism itself and that
|
||||
* something has gone horribly wrong with the TDX module.
|
||||
*
|
||||
* The return status of the hypercall operation is in a separate
|
||||
@ -154,30 +173,46 @@ SYM_FUNC_START(__tdx_hypercall)
|
||||
testq %rax, %rax
|
||||
jne .Lpanic
|
||||
|
||||
pop %rax
|
||||
|
||||
/* Copy hypercall result registers to arg struct if needed */
|
||||
testq $TDX_HCALL_HAS_OUTPUT, (%rsp)
|
||||
jz .Lout
|
||||
|
||||
movq %r8, TDX_HYPERCALL_r8(%rax)
|
||||
movq %r9, TDX_HYPERCALL_r9(%rax)
|
||||
movq %r10, TDX_HYPERCALL_r10(%rax)
|
||||
movq %r11, TDX_HYPERCALL_r11(%rax)
|
||||
movq %r12, TDX_HYPERCALL_r12(%rax)
|
||||
movq %r13, TDX_HYPERCALL_r13(%rax)
|
||||
movq %r14, TDX_HYPERCALL_r14(%rax)
|
||||
movq %r15, TDX_HYPERCALL_r15(%rax)
|
||||
movq %rdi, TDX_HYPERCALL_rdi(%rax)
|
||||
movq %rsi, TDX_HYPERCALL_rsi(%rax)
|
||||
movq %rbx, TDX_HYPERCALL_rbx(%rax)
|
||||
movq %rdx, TDX_HYPERCALL_rdx(%rax)
|
||||
.Lout:
|
||||
/* TDVMCALL leaf return code is in R10 */
|
||||
movq %r10, %rax
|
||||
|
||||
/* Copy hypercall result registers to arg struct if needed */
|
||||
testq $TDX_HCALL_HAS_OUTPUT, %rsi
|
||||
jz .Lout
|
||||
|
||||
movq %r10, TDX_HYPERCALL_r10(%rdi)
|
||||
movq %r11, TDX_HYPERCALL_r11(%rdi)
|
||||
movq %r12, TDX_HYPERCALL_r12(%rdi)
|
||||
movq %r13, TDX_HYPERCALL_r13(%rdi)
|
||||
movq %r14, TDX_HYPERCALL_r14(%rdi)
|
||||
movq %r15, TDX_HYPERCALL_r15(%rdi)
|
||||
.Lout:
|
||||
/*
|
||||
* Zero out registers exposed to the VMM to avoid speculative execution
|
||||
* with VMM-controlled values. This needs to include all registers
|
||||
* present in TDVMCALL_EXPOSE_REGS_MASK (except R12-R15). R12-R15
|
||||
* context will be restored.
|
||||
* present in TDVMCALL_EXPOSE_REGS_MASK, except RBX, and R12-R15 which
|
||||
* will be restored.
|
||||
*/
|
||||
xor %r8d, %r8d
|
||||
xor %r9d, %r9d
|
||||
xor %r10d, %r10d
|
||||
xor %r11d, %r11d
|
||||
xor %rdi, %rdi
|
||||
xor %rdx, %rdx
|
||||
|
||||
/* Remove TDX_HCALL_* flags from the stack */
|
||||
pop %rsi
|
||||
|
||||
/* Restore callee-saved GPRs as mandated by the x86_64 ABI */
|
||||
pop %rbx
|
||||
pop %r12
|
||||
pop %r13
|
||||
pop %r14
|
||||
|
||||
@ -19,9 +19,14 @@
|
||||
#define TDX_GET_VEINFO 3
|
||||
#define TDX_GET_REPORT 4
|
||||
#define TDX_ACCEPT_PAGE 6
|
||||
#define TDX_WR 8
|
||||
|
||||
/* TDCS fields. To be used by TDG.VM.WR and TDG.VM.RD module calls */
|
||||
#define TDCS_NOTIFY_ENABLES 0x9100000000000010
|
||||
|
||||
/* TDX hypercall Leaf IDs */
|
||||
#define TDVMCALL_MAP_GPA 0x10001
|
||||
#define TDVMCALL_REPORT_FATAL_ERROR 0x10003
|
||||
|
||||
/* MMIO direction */
|
||||
#define EPT_READ 0
|
||||
@ -37,6 +42,7 @@
|
||||
#define VE_GET_PORT_NUM(e) ((e) >> 16)
|
||||
#define VE_IS_IO_STRING(e) ((e) & BIT(4))
|
||||
|
||||
#define ATTR_DEBUG BIT(0)
|
||||
#define ATTR_SEPT_VE_DISABLE BIT(28)
|
||||
|
||||
/* TDX Module call error codes */
|
||||
@ -141,6 +147,41 @@ int tdx_mcall_get_report0(u8 *reportdata, u8 *tdreport)
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(tdx_mcall_get_report0);
|
||||
|
||||
static void __noreturn tdx_panic(const char *msg)
|
||||
{
|
||||
struct tdx_hypercall_args args = {
|
||||
.r10 = TDX_HYPERCALL_STANDARD,
|
||||
.r11 = TDVMCALL_REPORT_FATAL_ERROR,
|
||||
.r12 = 0, /* Error code: 0 is Panic */
|
||||
};
|
||||
union {
|
||||
/* Define register order according to the GHCI */
|
||||
struct { u64 r14, r15, rbx, rdi, rsi, r8, r9, rdx; };
|
||||
|
||||
char str[64];
|
||||
} message;
|
||||
|
||||
/* VMM assumes '\0' in byte 65, if the message took all 64 bytes */
|
||||
strncpy(message.str, msg, 64);
|
||||
|
||||
args.r8 = message.r8;
|
||||
args.r9 = message.r9;
|
||||
args.r14 = message.r14;
|
||||
args.r15 = message.r15;
|
||||
args.rdi = message.rdi;
|
||||
args.rsi = message.rsi;
|
||||
args.rbx = message.rbx;
|
||||
args.rdx = message.rdx;
|
||||
|
||||
/*
|
||||
* This hypercall should never return and it is not safe
|
||||
* to keep the guest running. Call it forever if it
|
||||
* happens to return.
|
||||
*/
|
||||
while (1)
|
||||
__tdx_hypercall(&args, 0);
|
||||
}
|
||||
|
||||
static void tdx_parse_tdinfo(u64 *cc_mask)
|
||||
{
|
||||
struct tdx_module_output out;
|
||||
@ -172,8 +213,15 @@ static void tdx_parse_tdinfo(u64 *cc_mask)
|
||||
* TD-private memory. Only VMM-shared memory (MMIO) will #VE.
|
||||
*/
|
||||
td_attr = out.rdx;
|
||||
if (!(td_attr & ATTR_SEPT_VE_DISABLE))
|
||||
panic("TD misconfiguration: SEPT_VE_DISABLE attibute must be set.\n");
|
||||
if (!(td_attr & ATTR_SEPT_VE_DISABLE)) {
|
||||
const char *msg = "TD misconfiguration: SEPT_VE_DISABLE attribute must be set.";
|
||||
|
||||
/* Relax SEPT_VE_DISABLE check for debug TD. */
|
||||
if (td_attr & ATTR_DEBUG)
|
||||
pr_warn("%s\n", msg);
|
||||
else
|
||||
tdx_panic(msg);
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
@ -617,6 +665,11 @@ static int virt_exception_user(struct pt_regs *regs, struct ve_info *ve)
|
||||
}
|
||||
}
|
||||
|
||||
static inline bool is_private_gpa(u64 gpa)
|
||||
{
|
||||
return gpa == cc_mkenc(gpa);
|
||||
}
|
||||
|
||||
/*
|
||||
* Handle the kernel #VE.
|
||||
*
|
||||
@ -635,6 +688,8 @@ static int virt_exception_kernel(struct pt_regs *regs, struct ve_info *ve)
|
||||
case EXIT_REASON_CPUID:
|
||||
return handle_cpuid(regs, ve);
|
||||
case EXIT_REASON_EPT_VIOLATION:
|
||||
if (is_private_gpa(ve->gpa))
|
||||
panic("Unexpected EPT-violation on private memory.");
|
||||
return handle_mmio(regs, ve);
|
||||
case EXIT_REASON_IO_INSTRUCTION:
|
||||
return handle_io(regs, ve);
|
||||
@ -801,6 +856,9 @@ void __init tdx_early_init(void)
|
||||
tdx_parse_tdinfo(&cc_mask);
|
||||
cc_set_mask(cc_mask);
|
||||
|
||||
/* Kernel does not use NOTIFY_ENABLES and does not need random #VEs */
|
||||
tdx_module_call(TDX_WR, 0, TDCS_NOTIFY_ENABLES, 0, -1ULL, NULL);
|
||||
|
||||
/*
|
||||
* All bits above GPA width are reserved and kernel treats shared bit
|
||||
* as flag, not as part of physical address.
|
||||
|
||||
@ -21,12 +21,18 @@
|
||||
* This is a software only structure and not part of the TDX module/VMM ABI.
|
||||
*/
|
||||
struct tdx_hypercall_args {
|
||||
u64 r8;
|
||||
u64 r9;
|
||||
u64 r10;
|
||||
u64 r11;
|
||||
u64 r12;
|
||||
u64 r13;
|
||||
u64 r14;
|
||||
u64 r15;
|
||||
u64 rdi;
|
||||
u64 rsi;
|
||||
u64 rbx;
|
||||
u64 rdx;
|
||||
};
|
||||
|
||||
/* Used to request services from the VMM */
|
||||
|
||||
@ -76,12 +76,18 @@ static void __used common(void)
|
||||
OFFSET(TDX_MODULE_r11, tdx_module_output, r11);
|
||||
|
||||
BLANK();
|
||||
OFFSET(TDX_HYPERCALL_r8, tdx_hypercall_args, r8);
|
||||
OFFSET(TDX_HYPERCALL_r9, tdx_hypercall_args, r9);
|
||||
OFFSET(TDX_HYPERCALL_r10, tdx_hypercall_args, r10);
|
||||
OFFSET(TDX_HYPERCALL_r11, tdx_hypercall_args, r11);
|
||||
OFFSET(TDX_HYPERCALL_r12, tdx_hypercall_args, r12);
|
||||
OFFSET(TDX_HYPERCALL_r13, tdx_hypercall_args, r13);
|
||||
OFFSET(TDX_HYPERCALL_r14, tdx_hypercall_args, r14);
|
||||
OFFSET(TDX_HYPERCALL_r15, tdx_hypercall_args, r15);
|
||||
OFFSET(TDX_HYPERCALL_rdi, tdx_hypercall_args, rdi);
|
||||
OFFSET(TDX_HYPERCALL_rsi, tdx_hypercall_args, rsi);
|
||||
OFFSET(TDX_HYPERCALL_rbx, tdx_hypercall_args, rbx);
|
||||
OFFSET(TDX_HYPERCALL_rdx, tdx_hypercall_args, rdx);
|
||||
|
||||
BLANK();
|
||||
OFFSET(BP_scratch, boot_params, scratch);
|
||||
|
||||
Loading…
Reference in New Issue
Block a user