diff options
| -rw-r--r-- | arch/x86/coco/tdx/tdcall.S | 13 | ||||
| -rw-r--r-- | arch/x86/coco/tdx/tdx.c | 23 | ||||
| -rw-r--r-- | arch/x86/include/asm/shared/tdx.h | 1 |
3 files changed, 4 insertions, 33 deletions
diff --git a/arch/x86/coco/tdx/tdcall.S b/arch/x86/coco/tdx/tdcall.S index f9eb1134f22d..508c17332e2e 100644 --- a/arch/x86/coco/tdx/tdcall.S +++ b/arch/x86/coco/tdx/tdcall.S @@ -139,19 +139,6 @@ SYM_FUNC_START(__tdx_hypercall) movl $TDVMCALL_EXPOSE_REGS_MASK, %ecx - /* - * For the idle loop STI needs to be called directly before the TDCALL - * that enters idle (EXIT_REASON_HLT case). STI instruction enables - * interrupts only one instruction later. If there is a window between - * STI and the instruction that emulates the HALT state, there is a - * chance for interrupts to happen in this window, which can delay the - * HLT operation indefinitely. Since this is the not the desired - * result, conditionally call STI before TDCALL. - */ - testq $TDX_HCALL_ISSUE_STI, %rsi - jz .Lskip_sti - sti -.Lskip_sti: tdcall /* diff --git a/arch/x86/coco/tdx/tdx.c b/arch/x86/coco/tdx/tdx.c index f4a59c365321..8804174aef1a 100644 --- a/arch/x86/coco/tdx/tdx.c +++ b/arch/x86/coco/tdx/tdx.c @@ -220,7 +220,7 @@ static int ve_instr_len(struct ve_info *ve) } } -static u64 __cpuidle __halt(const bool irq_disabled, const bool do_sti) +static u64 __cpuidle __halt(const bool irq_disabled) { struct tdx_hypercall_args args = { .r10 = TDX_HYPERCALL_STANDARD, @@ -240,20 +240,14 @@ static u64 __cpuidle __halt(const bool irq_disabled, const bool do_sti) * can keep the vCPU in virtual HLT, even if an IRQ is * pending, without hanging/breaking the guest. */ - return __tdx_hypercall(&args, do_sti ? TDX_HCALL_ISSUE_STI : 0); + return __tdx_hypercall(&args, 0); } static int handle_halt(struct ve_info *ve) { - /* - * Since non safe halt is mainly used in CPU offlining - * and the guest will always stay in the halt state, don't - * call the STI instruction (set do_sti as false). - */ const bool irq_disabled = irqs_disabled(); - const bool do_sti = false; - if (__halt(irq_disabled, do_sti)) + if (__halt(irq_disabled)) return -EIO; return ve_instr_len(ve); @@ -261,22 +255,13 @@ static int handle_halt(struct ve_info *ve) void __cpuidle tdx_safe_halt(void) { - /* - * For do_sti=true case, __tdx_hypercall() function enables - * interrupts using the STI instruction before the TDCALL. So - * set irq_disabled as false. - */ const bool irq_disabled = false; - const bool do_sti = true; /* * Use WARN_ONCE() to report the failure. */ - if (__halt(irq_disabled, do_sti)) + if (__halt(irq_disabled)) WARN_ONCE(1, "HLT instruction emulation failed\n"); - - /* XXX I can't make sense of what @do_sti actually does */ - raw_local_irq_disable(); } static int read_msr(struct pt_regs *regs, struct ve_info *ve) diff --git a/arch/x86/include/asm/shared/tdx.h b/arch/x86/include/asm/shared/tdx.h index e53f26228fbb..559176887791 100644 --- a/arch/x86/include/asm/shared/tdx.h +++ b/arch/x86/include/asm/shared/tdx.h @@ -8,7 +8,6 @@ #define TDX_HYPERCALL_STANDARD 0 #define TDX_HCALL_HAS_OUTPUT BIT(0) -#define TDX_HCALL_ISSUE_STI BIT(1) #define TDX_CPUID_LEAF_ID 0x21 #define TDX_IDENT "IntelTDX " |