/*
* 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)
* 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 )
/*
* __tdx_module_call() - Used by TDX guests to request services from
push %r14
push %r13
push %r12
+ push %rbx
push %rbp
/* Free RDI and RSI to be used as TDVMCALL arguments */
movq %rsi, %rbp
/* 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
testq $TDX_HCALL_HAS_OUTPUT, %rbp
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
/*
* 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 %rsi, %rsi
+ xor %rdx, %rdx
/* Restore callee-saved GPRs as mandated by the x86_64 ABI */
pop %rbp
+ pop %rbx
pop %r12
pop %r13
pop %r14