[PATCHv3 1/3] x86/tdx: Fix early #VE handling

From: Kirill A. Shutemov
Date: Tue May 24 2022 - 18:10:49 EST


Move RIP in tdx_early_handle_ve() after handling the exception. Failure
to do that leads to infinite loop of exceptions.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Fixes: 32e72854fa5f ("x86/tdx: Port I/O: Add early boot support")
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx>
---
arch/x86/coco/tdx/tdx.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/arch/x86/coco/tdx/tdx.c b/arch/x86/coco/tdx/tdx.c
index 03deb4d6920d..faae53f8d559 100644
--- a/arch/x86/coco/tdx/tdx.c
+++ b/arch/x86/coco/tdx/tdx.c
@@ -447,13 +447,17 @@ static bool handle_io(struct pt_regs *regs, u32 exit_qual)
__init bool tdx_early_handle_ve(struct pt_regs *regs)
{
struct ve_info ve;
+ bool ret;

tdx_get_ve_info(&ve);

if (ve.exit_reason != EXIT_REASON_IO_INSTRUCTION)
return false;

- return handle_io(regs, ve.exit_qual);
+ ret = handle_io(regs, ve.exit_qual);
+ if (ret)
+ regs->ip += ve.instr_len;
+ return ret;
}

void tdx_get_ve_info(struct ve_info *ve)
--
2.35.1