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Message-ID: <c22a4697cfe90ab4e1de18d27aa48ea2152dbcfa.1689151537.git.kai.huang@intel.com>
Date: Wed, 12 Jul 2023 20:55:22 +1200
From: Kai Huang <kai.huang@...el.com>
To: peterz@...radead.org, kirill.shutemov@...ux.intel.com,
linux-kernel@...r.kernel.org
Cc: dave.hansen@...el.com, tglx@...utronix.de, bp@...en8.de,
mingo@...hat.com, hpa@...or.com, x86@...nel.org, seanjc@...gle.com,
pbonzini@...hat.com, kvm@...r.kernel.org, isaku.yamahata@...el.com,
sathyanarayanan.kuppuswamy@...ux.intel.com, kai.huang@...el.com
Subject: [PATCH 08/10] x86/tdx: Unify TDX_HYPERCALL and TDX_MODULE_CALL assembly
Now TDX_HYPERCALL macro shares very similar code pattern with the
TDX_MODULE_CALL macro, except that TDX_HYPERCALL handles below
additional things:
1) Sets RAX to 0 (TDG.VP.VMCALL leaf) internally;
2) Sets RCX to the (fixed) bitmap of shared registers;
3) Panics internally if the TDCALL return code is not zero;
4) After TDCALL, moves R10 to RAX for returning the return code of the
TDVMCALL itself, regardless the "\ret" parameter;
5) Clears shared registers to prevent speculative use of VMM's values.
Using the TDX_MODULE_CALL macro, 1) - 3) can be moved out to the C code.
4) can be done by always turning on the TDX_MODULE_CALL macro's "\ret"
parameter, and moving it to the C function. 5) is already covered by
the TDH.VP.ENTER in the TDX_MODULE_CALL.
In other words, the TDX_HYPERCALL macro is redundant now and should be
removed to use TDX_MODULE_CALL macro instead.
TDVMCALL always uses the extra "callee-saved" registers. Replace the
existing __tdx_hypercall{_ret}() assembly functions with a new
__tdcall_saved_ret(), as mentioned above TDVMCALL relies on saving R10
to the register structure so that the caller (C function) can use it as
the return code of the TDVMCALL itself.
As a result, reimplement the existing __tdx_hypercall() using the
__tdcall_saved_ret() function. __tdx_hypercall_ret() isn't necessary
anymore because __tdx_hypercall() always turns on the "\ret" parameter.
Also remove the 'struct tdx_hypercall_args', which has the exact members
as the 'struct tdx_module_args' (except the RCX which isn't used as
shared register). It's not worth to keep the structure just for one
member.
With this change, the __tdx_hypercall() variants are not implemented in
tdcall.S anymore thus not available to the compressed code. Implement
the __tdx_hypercall() variants in the compressed code directly using the
__tdcall_saved_ret().
Opportunistically fix a checkpatch error complaining using space around
parenthesis '(' and ')' while moving the bitmap of shared registers to
<asm/shared/tdx.h>.
Cc: Kirill A. Shutemov <kirill.shutemov@...ux.intel.com>
Cc: Dave Hansen <dave.hansen@...ux.intel.com>
Cc: Peter Zijlstra <peterz@...radead.org>
Suggested-by: Peter Zijlstra <peterz@...radead.org>
Signed-off-by: Kai Huang <kai.huang@...el.com>
---
arch/x86/boot/compressed/tdx.c | 26 +++-
arch/x86/coco/tdx/tdcall.S | 194 ++++--------------------------
arch/x86/coco/tdx/tdx.c | 62 ++++++----
arch/x86/include/asm/shared/tdx.h | 48 ++++++--
arch/x86/include/asm/tdx.h | 25 ----
arch/x86/kernel/asm-offsets.c | 14 ---
arch/x86/virt/vmx/tdx/tdxcall.S | 10 +-
7 files changed, 127 insertions(+), 252 deletions(-)
diff --git a/arch/x86/boot/compressed/tdx.c b/arch/x86/boot/compressed/tdx.c
index 8841b945a1e2..4df2259f9f7f 100644
--- a/arch/x86/boot/compressed/tdx.c
+++ b/arch/x86/boot/compressed/tdx.c
@@ -11,14 +11,32 @@
#include <asm/shared/tdx.h>
/* Called from __tdx_hypercall() for unrecoverable failure */
-void __tdx_hypercall_failed(void)
+static inline void __tdx_hypercall_failed(void)
{
error("TDVMCALL failed. TDX module bug?");
}
+static inline u64 __tdx_hypercall(struct tdx_module_args *args)
+{
+ u64 ret;
+
+ args->rcx = TDVMCALL_EXPOSE_REGS_MASK;
+ ret = __tdcall_saved_ret(TDG_VP_VMCALL, args);
+
+ /*
+ * RAX!=0 indicates a failure of the TDVMCALL mechanism itself and that
+ * something has gone horribly wrong with the TDX module.
+ */
+ if (ret)
+ __tdx_hypercall_failed();
+
+ /* The return status of the hypercall itself is in R10. */
+ return args->r10;
+}
+
static inline unsigned int tdx_io_in(int size, u16 port)
{
- struct tdx_hypercall_args args = {
+ struct tdx_module_args args = {
.r10 = TDX_HYPERCALL_STANDARD,
.r11 = hcall_func(EXIT_REASON_IO_INSTRUCTION),
.r12 = size,
@@ -26,7 +44,7 @@ static inline unsigned int tdx_io_in(int size, u16 port)
.r14 = port,
};
- if (__tdx_hypercall_ret(&args))
+ if (__tdx_hypercall(&args))
return UINT_MAX;
return args.r11;
@@ -34,7 +52,7 @@ static inline unsigned int tdx_io_in(int size, u16 port)
static inline void tdx_io_out(int size, u16 port, u32 value)
{
- struct tdx_hypercall_args args = {
+ struct tdx_module_args args = {
.r10 = TDX_HYPERCALL_STANDARD,
.r11 = hcall_func(EXIT_REASON_IO_INSTRUCTION),
.r12 = size,
diff --git a/arch/x86/coco/tdx/tdcall.S b/arch/x86/coco/tdx/tdcall.S
index d5693330ee9b..6f3c9028577b 100644
--- a/arch/x86/coco/tdx/tdcall.S
+++ b/arch/x86/coco/tdx/tdcall.S
@@ -10,38 +10,11 @@
#include "../../virt/vmx/tdx/tdxcall.S"
-/*
- * 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)
-#define TDX_R13 BIT(13)
-#define TDX_R14 BIT(14)
-#define TDX_R15 BIT(15)
-
-/*
- * These registers are clobbered to hold arguments for each
- * TDVMCALL. They are safe to expose to the VMM.
- * Each bit in this mask represents a register ID. Bit field
- * details can be found in TDX GHCI specification, section
- * titled "TDCALL [TDG.VP.VMCALL] leaf".
- */
-#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"
/*
* __tdcall() - Used by TDX guests to request services from the TDX
- * module (does not include VMM services) using TDCALL instruction.
+ * module using TDCALL instruction.
*
* __tdcall() function ABI:
*
@@ -56,7 +29,7 @@ SYM_FUNC_END(__tdcall)
/*
* __tdcall_ret() - Used by TDX guests to request services from the TDX
- * module (does not include VMM services) using TDCALL instruction.
+ * module using TDCALL instruction.
*
* __tdcall_ret() function ABI:
*
@@ -70,156 +43,33 @@ SYM_FUNC_START(__tdcall_ret)
SYM_FUNC_END(__tdcall_ret)
/*
- * TDX_HYPERCALL - Make hypercalls to a TDX VMM using TDVMCALL leaf of TDCALL
- * instruction
+ * __tdcall_saved() - Used by the TDX guests to request services from the
+ * TDX module using TDCALL instruction with additional callee-saved
+ * registers as input.
*
- * Transforms values in function call argument struct tdx_hypercall_args @args
- * into the TDCALL register ABI. After TDCALL operation, VMM output is saved
- * back in @args, if \ret is 1.
+ * __tdcall_saved() function ABI:
*
- *-------------------------------------------------------------------------
- * TD VMCALL ABI:
- *-------------------------------------------------------------------------
+ * @fn (RDI) - TDCALL leaf ID, moved to RAX
+ * @args (RSI) - struct 'struct tdx_module_args' for input
*
- * Input Registers:
- *
- * RAX - TDCALL instruction leaf number (0 - TDG.VP.VMCALL)
- * RCX - BITMAP which controls which part of TD Guest GPR
- * is passed as-is to the VMM and back.
- * R10 - Set 0 to indicate TDCALL follows standard TDX ABI
- * specification. Non zero value indicates vendor
- * specific ABI.
- * R11 - VMCALL sub function number
- * RBX, RDX, RDI, RSI - Used to pass VMCALL sub function specific arguments.
- * R8-R9, R12-R15 - Same as above.
- *
- * Output Registers:
- *
- * RAX - TDCALL instruction status (Not related to hypercall
- * output).
- * RBX, RDX, RDI, RSI - Hypercall sub function specific output values.
- * R8-R15 - Same as above.
- *
- */
-.macro TDX_HYPERCALL ret:req
- FRAME_BEGIN
-
- /* Save callee-saved GPRs as mandated by the x86_64 ABI */
- push %r15
- push %r14
- push %r13
- push %r12
- push %rbx
-
- /* Free RDI to be used as TDVMCALL arguments */
- movq %rdi, %rax
-
- /* 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
-
- movl $TDVMCALL_EXPOSE_REGS_MASK, %ecx
-
- tdcall
-
- /*
- * 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
- * register (in R10). Hypercall errors are a part of normal operation
- * and are handled by callers.
- */
- testq %rax, %rax
- jne .Lpanic\@
-
- pop %rax
-
- .if \ret
- 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)
- .endif
-
- /* TDVMCALL leaf return code is in R10 */
- movq %r10, %rax
-
- /*
- * 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 RBX, and R12-R15 which
- * will be restored.
- */
- xor %r8d, %r8d
- xor %r9d, %r9d
- xor %r10d, %r10d
- xor %r11d, %r11d
- xor %rdi, %rdi
- xor %rsi, %rsi
- xor %rdx, %rdx
-
- /* Restore callee-saved GPRs as mandated by the x86_64 ABI */
- pop %rbx
- pop %r12
- pop %r13
- pop %r14
- pop %r15
-
- FRAME_END
-
- RET
-.Lpanic\@:
- call __tdx_hypercall_failed
- /* __tdx_hypercall_failed never returns */
- REACHABLE
- jmp .Lpanic\@
-.endm
-
-/*
- *
- * __tdx_hypercall() function ABI:
- *
- * @args (RDI) - struct tdx_hypercall_args for input
- *
- * On successful completion, return the hypercall error code.
+ * Return the TDCALL return code (RAX)
*/
-SYM_FUNC_START(__tdx_hypercall)
- TDX_HYPERCALL ret=0
-SYM_FUNC_END(__tdx_hypercall)
+SYM_FUNC_START(__tdcall_saved)
+ TDX_MODULE_CALL host=0 ret=0 saved=1
+SYM_FUNC_END(__tdcall_saved)
/*
+ * __tdcall_saved_ret() - Used by the TDX guests to request services from the
+ * TDX module using TDCALL instruction with additional callee-saved registers
+ * as input/output.
*
- * __tdx_hypercall_ret() function ABI:
+ * __tdcall_saved_ret() function ABI:
*
- * @args (RDI) - struct tdx_hypercall_args for input and output
+ * @fn (RDI) - TDCALL leaf ID, moved to RAX
+ * @args (RDI) - struct 'struct tdx_module_args' for input and output
*
- * On successful completion, return the hypercall error code.
+ * Return the TDCALL return code (RAX)
*/
-SYM_FUNC_START(__tdx_hypercall_ret)
- TDX_HYPERCALL ret=1
-SYM_FUNC_END(__tdx_hypercall_ret)
+SYM_FUNC_START(__tdcall_saved_ret)
+ TDX_MODULE_CALL host=0 ret=1 saved=1
+SYM_FUNC_END(__tdcall_saved_ret)
diff --git a/arch/x86/coco/tdx/tdx.c b/arch/x86/coco/tdx/tdx.c
index 0f16ba52ae62..a5e77893b2c0 100644
--- a/arch/x86/coco/tdx/tdx.c
+++ b/arch/x86/coco/tdx/tdx.c
@@ -51,13 +51,38 @@
#define TDREPORT_SUBTYPE_0 0
+/* Called from __tdx_hypercall() for unrecoverable failure */
+static noinstr void __tdx_hypercall_failed(void)
+{
+ instrumentation_begin();
+ panic("TDVMCALL failed. TDX module bug?");
+}
+
+static inline u64 __tdx_hypercall(struct tdx_module_args *args)
+{
+ u64 ret;
+
+ args->rcx = TDVMCALL_EXPOSE_REGS_MASK;
+ ret = __tdcall_saved_ret(TDG_VP_VMCALL, args);
+
+ /*
+ * RAX!=0 indicates a failure of the TDVMCALL mechanism itself and that
+ * something has gone horribly wrong with the TDX module.
+ */
+ if (ret)
+ __tdx_hypercall_failed();
+
+ /* The return status of the hypercall itself is in R10. */
+ return args->r10;
+}
+
/*
- * Wrapper for standard use of __tdx_hypercall with no output aside from
- * return code.
+ * Wrapper for standard use of __tdx_hypercall() w/o needing any output
+ * register except the return code.
*/
static inline u64 _tdx_hypercall(u64 fn, u64 r12, u64 r13, u64 r14, u64 r15)
{
- struct tdx_hypercall_args args = {
+ struct tdx_module_args args = {
.r10 = TDX_HYPERCALL_STANDARD,
.r11 = fn,
.r12 = r12,
@@ -69,18 +94,11 @@ static inline u64 _tdx_hypercall(u64 fn, u64 r12, u64 r13, u64 r14, u64 r15)
return __tdx_hypercall(&args);
}
-/* Called from __tdx_hypercall() for unrecoverable failure */
-noinstr void __tdx_hypercall_failed(void)
-{
- instrumentation_begin();
- panic("TDVMCALL failed. TDX module bug?");
-}
-
#ifdef CONFIG_KVM_GUEST
long tdx_kvm_hypercall(unsigned int nr, unsigned long p1, unsigned long p2,
unsigned long p3, unsigned long p4)
{
- struct tdx_hypercall_args args = {
+ struct tdx_module_args args = {
.r10 = nr,
.r11 = p1,
.r12 = p2,
@@ -140,7 +158,7 @@ EXPORT_SYMBOL_GPL(tdx_mcall_get_report0);
static void __noreturn tdx_panic(const char *msg)
{
- struct tdx_hypercall_args args = {
+ struct tdx_module_args args = {
.r10 = TDX_HYPERCALL_STANDARD,
.r11 = TDVMCALL_REPORT_FATAL_ERROR,
.r12 = 0, /* Error code: 0 is Panic */
@@ -262,7 +280,7 @@ static int ve_instr_len(struct ve_info *ve)
static u64 __cpuidle __halt(const bool irq_disabled)
{
- struct tdx_hypercall_args args = {
+ struct tdx_module_args args = {
.r10 = TDX_HYPERCALL_STANDARD,
.r11 = hcall_func(EXIT_REASON_HLT),
.r12 = irq_disabled,
@@ -306,7 +324,7 @@ void __cpuidle tdx_safe_halt(void)
static int read_msr(struct pt_regs *regs, struct ve_info *ve)
{
- struct tdx_hypercall_args args = {
+ struct tdx_module_args args = {
.r10 = TDX_HYPERCALL_STANDARD,
.r11 = hcall_func(EXIT_REASON_MSR_READ),
.r12 = regs->cx,
@@ -317,7 +335,7 @@ static int read_msr(struct pt_regs *regs, struct ve_info *ve)
* can be found in TDX Guest-Host-Communication Interface
* (GHCI), section titled "TDG.VP.VMCALL<Instruction.RDMSR>".
*/
- if (__tdx_hypercall_ret(&args))
+ if (__tdx_hypercall(&args))
return -EIO;
regs->ax = lower_32_bits(args.r11);
@@ -327,7 +345,7 @@ static int read_msr(struct pt_regs *regs, struct ve_info *ve)
static int write_msr(struct pt_regs *regs, struct ve_info *ve)
{
- struct tdx_hypercall_args args = {
+ struct tdx_module_args args = {
.r10 = TDX_HYPERCALL_STANDARD,
.r11 = hcall_func(EXIT_REASON_MSR_WRITE),
.r12 = regs->cx,
@@ -347,7 +365,7 @@ static int write_msr(struct pt_regs *regs, struct ve_info *ve)
static int handle_cpuid(struct pt_regs *regs, struct ve_info *ve)
{
- struct tdx_hypercall_args args = {
+ struct tdx_module_args args = {
.r10 = TDX_HYPERCALL_STANDARD,
.r11 = hcall_func(EXIT_REASON_CPUID),
.r12 = regs->ax,
@@ -371,7 +389,7 @@ static int handle_cpuid(struct pt_regs *regs, struct ve_info *ve)
* ABI can be found in TDX Guest-Host-Communication Interface
* (GHCI), section titled "VP.VMCALL<Instruction.CPUID>".
*/
- if (__tdx_hypercall_ret(&args))
+ if (__tdx_hypercall(&args))
return -EIO;
/*
@@ -389,7 +407,7 @@ static int handle_cpuid(struct pt_regs *regs, struct ve_info *ve)
static bool mmio_read(int size, unsigned long addr, unsigned long *val)
{
- struct tdx_hypercall_args args = {
+ struct tdx_module_args args = {
.r10 = TDX_HYPERCALL_STANDARD,
.r11 = hcall_func(EXIT_REASON_EPT_VIOLATION),
.r12 = size,
@@ -398,7 +416,7 @@ static bool mmio_read(int size, unsigned long addr, unsigned long *val)
.r15 = *val,
};
- if (__tdx_hypercall_ret(&args))
+ if (__tdx_hypercall(&args))
return false;
*val = args.r11;
return true;
@@ -517,7 +535,7 @@ static int handle_mmio(struct pt_regs *regs, struct ve_info *ve)
static bool handle_in(struct pt_regs *regs, int size, int port)
{
- struct tdx_hypercall_args args = {
+ struct tdx_module_args args = {
.r10 = TDX_HYPERCALL_STANDARD,
.r11 = hcall_func(EXIT_REASON_IO_INSTRUCTION),
.r12 = size,
@@ -532,7 +550,7 @@ static bool handle_in(struct pt_regs *regs, int size, int port)
* in TDX Guest-Host-Communication Interface (GHCI) section titled
* "TDG.VP.VMCALL<Instruction.IO>".
*/
- success = !__tdx_hypercall_ret(&args);
+ success = !__tdx_hypercall(&args);
/* Update part of the register affected by the emulated instruction */
regs->ax &= ~mask;
diff --git a/arch/x86/include/asm/shared/tdx.h b/arch/x86/include/asm/shared/tdx.h
index b415a24f0d48..f2a6e76dd773 100644
--- a/arch/x86/include/asm/shared/tdx.h
+++ b/arch/x86/include/asm/shared/tdx.h
@@ -13,32 +13,60 @@
#ifndef __ASSEMBLY__
/*
- * Used in __tdx_hypercall() to pass down and get back registers' values of
- * the TDCALL instruction when requesting services from the VMM.
+ * Used to gather input/output registers of the TDCALL and SEAMCALL
+ * instructions when requesting services from the TDX module.
*
* This is a software only structure and not part of the TDX module/VMM ABI.
*/
-struct tdx_hypercall_args {
+struct tdx_module_args {
+ /* callee-clobbered */
+ u64 rcx;
+ u64 rdx;
u64 r8;
u64 r9;
+ /* extra callee-clobbered */
u64 r10;
u64 r11;
+ /* callee-saved + rdi/rsi */
u64 r12;
u64 r13;
u64 r14;
u64 r15;
+ u64 rbx;
u64 rdi;
u64 rsi;
- u64 rbx;
- u64 rdx;
};
-/* Used to request services from the VMM */
-u64 __tdx_hypercall(struct tdx_hypercall_args *args);
-u64 __tdx_hypercall_ret(struct tdx_hypercall_args *args);
+#define TDG_VP_VMCALL 0
-/* Called from __tdx_hypercall() for unrecoverable failure */
-void __tdx_hypercall_failed(void);
+/*
+ * 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)
+#define TDX_R13 BIT(13)
+#define TDX_R14 BIT(14)
+#define TDX_R15 BIT(15)
+
+/*
+ * These registers are clobbered to hold arguments for each
+ * TDVMCALL. They are safe to expose to the VMM.
+ * Each bit in this mask represents a register ID. Bit field
+ * details can be found in TDX GHCI specification, section
+ * titled "TDCALL [TDG.VP.VMCALL] leaf".
+ */
+#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)
+
+u64 __tdcall_saved_ret(u64 fn, struct tdx_module_args *args);
/*
* The TDG.VP.VMCALL-Instruction-execution sub-functions are defined
diff --git a/arch/x86/include/asm/tdx.h b/arch/x86/include/asm/tdx.h
index a549bcc77f4f..9b0ad0176e58 100644
--- a/arch/x86/include/asm/tdx.h
+++ b/arch/x86/include/asm/tdx.h
@@ -20,31 +20,6 @@
#ifndef __ASSEMBLY__
-/*
- * Used to gather input/output registers of the TDCALL and SEAMCALL
- * instructions when requesting services from the TDX module.
- *
- * This is a software only structure and not part of the TDX module/VMM ABI.
- */
-struct tdx_module_args {
- /* callee-clobbered */
- u64 rcx;
- u64 rdx;
- u64 r8;
- u64 r9;
- /* extra callee-clobbered */
- u64 r10;
- u64 r11;
- /* callee-saved + rdi/rsi */
- u64 r12;
- u64 r13;
- u64 r14;
- u64 r15;
- u64 rbx;
- u64 rdi;
- u64 rsi;
-};
-
/*
* Used by the #VE exception handler to gather the #VE exception
* info from the TDX module. This is a software only structure
diff --git a/arch/x86/kernel/asm-offsets.c b/arch/x86/kernel/asm-offsets.c
index 1581564a67b7..6913b372ccf7 100644
--- a/arch/x86/kernel/asm-offsets.c
+++ b/arch/x86/kernel/asm-offsets.c
@@ -82,20 +82,6 @@ static void __used common(void)
OFFSET(TDX_MODULE_rdi, tdx_module_args, rdi);
OFFSET(TDX_MODULE_rsi, tdx_module_args, rsi);
- 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);
OFFSET(BP_secure_boot, boot_params, secure_boot);
diff --git a/arch/x86/virt/vmx/tdx/tdxcall.S b/arch/x86/virt/vmx/tdx/tdxcall.S
index 389f4ec5eee8..e4e90ebf5dad 100644
--- a/arch/x86/virt/vmx/tdx/tdxcall.S
+++ b/arch/x86/virt/vmx/tdx/tdxcall.S
@@ -145,11 +145,11 @@
.endif /* \ret */
.if \saved
- .if \ret && \host
+ .if \ret
/*
- * Clear registers shared by guest for VP.ENTER to prevent
- * speculative use of guest's values, including those are
- * restored from the stack.
+ * Clear registers shared by guest for VP.ENTER and VP.VMCALL to
+ * prevent speculative use of values from guest/VMM, including
+ * those are restored from the stack.
*
* See arch/x86/kvm/vmx/vmenter.S:
*
@@ -173,7 +173,7 @@
xorq %r15, %r15
xorq %rbx, %rbx
xorq %rdi, %rdi
- .endif /* \ret && \host */
+ .endif /* \ret */
/* Restore callee-saved GPRs as mandated by the x86_64 ABI */
popq %r15
--
2.41.0
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