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authorKirill A. Shutemov <kirill.shutemov@linux.intel.com>2023-01-30 16:53:54 +0300
committerDave Hansen <dave.hansen@linux.intel.com>2023-02-03 03:31:25 +0300
commit1e70c680375aa33cca97bff0bca68c0f82f5023c (patch)
treed73e781b56e3cf66517d1ad079257aa4b1d9a628 /arch/x86/coco
parent8de62af018cc9262649d7688f7eb1409b2d8f594 (diff)
downloadlinux-1e70c680375aa33cca97bff0bca68c0f82f5023c.tar.xz
x86/tdx: Do not corrupt frame-pointer in __tdx_hypercall()
If compiled with CONFIG_FRAME_POINTER=y, objtool is not happy that __tdx_hypercall() messes up RBP: objtool: __tdx_hypercall+0x7f: return with modified stack frame Rework the function to store TDX_HCALL_ flags on stack instead of RBP. [ dhansen: minor changelog tweaks ] Fixes: c30c4b2555ba ("x86/tdx: Refactor __tdx_hypercall() to allow pass down more arguments") Reported-by: kernel test robot <lkp@intel.com> 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/202301290255.buUBs99R-lkp@intel.com Link: https://lore.kernel.org/all/20230130135354.27674-1-kirill.shutemov%40linux.intel.com
Diffstat (limited to 'arch/x86/coco')
-rw-r--r--arch/x86/coco/tdx/tdcall.S12
1 files changed, 6 insertions, 6 deletions
diff --git a/arch/x86/coco/tdx/tdcall.S b/arch/x86/coco/tdx/tdcall.S
index 5da06d1a9ba3..2bd436a4790d 100644
--- a/arch/x86/coco/tdx/tdcall.S
+++ b/arch/x86/coco/tdx/tdcall.S
@@ -131,11 +131,10 @@ SYM_FUNC_START(__tdx_hypercall)
push %r13
push %r12
push %rbx
- push %rbp
/* Free RDI and RSI to be used as TDVMCALL arguments */
movq %rdi, %rax
- movq %rsi, %rbp
+ push %rsi
/* Copy hypercall registers from arg struct: */
movq TDX_HYPERCALL_r8(%rax), %r8
@@ -168,7 +167,7 @@ SYM_FUNC_START(__tdx_hypercall)
* HLT operation indefinitely. Since this is the not the desired
* result, conditionally call STI before TDCALL.
*/
- testq $TDX_HCALL_ISSUE_STI, %rbp
+ testq $TDX_HCALL_ISSUE_STI, 8(%rsp)
jz .Lskip_sti
sti
.Lskip_sti:
@@ -188,7 +187,7 @@ SYM_FUNC_START(__tdx_hypercall)
pop %rax
/* Copy hypercall result registers to arg struct if needed */
- testq $TDX_HCALL_HAS_OUTPUT, %rbp
+ testq $TDX_HCALL_HAS_OUTPUT, (%rsp)
jz .Lout
movq %r8, TDX_HYPERCALL_r8(%rax)
@@ -218,11 +217,12 @@ SYM_FUNC_START(__tdx_hypercall)
xor %r10d, %r10d
xor %r11d, %r11d
xor %rdi, %rdi
- xor %rsi, %rsi
xor %rdx, %rdx
+ /* Remove TDX_HCALL_* flags from the stack */
+ pop %rsi
+
/* Restore callee-saved GPRs as mandated by the x86_64 ABI */
- pop %rbp
pop %rbx
pop %r12
pop %r13