diff options
| author | Kirill A. Shutemov <kirill.shutemov@linux.intel.com> | 2023-01-26 23:11:56 +0100 |
|---|---|---|
| committer | Dave Hansen <dave.hansen@linux.intel.com> | 2023-01-27 18:42:09 +0100 |
| commit | 752d13305c78b2f0f0d783132f94acc9ce93d38e (patch) | |
| tree | 586bc7ec7459f1c37de288299e4be7b0e7591b2c /arch/x86/coco | |
| parent | x86/tdx: Refactor __tdx_hypercall() to allow pass down more arguments (diff) | |
| download | linux-752d13305c78b2f0f0d783132f94acc9ce93d38e.tar.xz linux-752d13305c78b2f0f0d783132f94acc9ce93d38e.zip | |
x86/tdx: Expand __tdx_hypercall() to handle more arguments
So far __tdx_hypercall() only handles six arguments for VMCALL.
Expanding it to six more register would allow to cover more use-cases
like ReportFatalError() and Hyper-V hypercalls.
With all preparations in place, the expansion is pretty straight
forward.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lore.kernel.org/all/20230126221159.8635-5-kirill.shutemov%40linux.intel.com
Diffstat (limited to 'arch/x86/coco')
| -rw-r--r-- | arch/x86/coco/tdx/tdcall.S | 35 |
1 files changed, 30 insertions, 5 deletions
diff --git a/arch/x86/coco/tdx/tdcall.S b/arch/x86/coco/tdx/tdcall.S index a9bb4cbb8197..5da06d1a9ba3 100644 --- a/arch/x86/coco/tdx/tdcall.S +++ b/arch/x86/coco/tdx/tdcall.S @@ -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 ) /* * __tdx_module_call() - Used by TDX guests to request services from @@ -124,6 +130,7 @@ SYM_FUNC_START(__tdx_hypercall) push %r14 push %r13 push %r12 + push %rbx push %rbp /* Free RDI and RSI to be used as TDVMCALL arguments */ @@ -131,12 +138,18 @@ SYM_FUNC_START(__tdx_hypercall) 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 @@ -178,12 +191,18 @@ SYM_FUNC_START(__tdx_hypercall) 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 @@ -191,14 +210,20 @@ SYM_FUNC_START(__tdx_hypercall) /* * 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 |