diff options
Diffstat (limited to 'arch/x86/coco/tdx')
| -rw-r--r-- | arch/x86/coco/tdx/tdcall.S | 15 | ||||
| -rw-r--r-- | arch/x86/coco/tdx/tdx.c | 25 |
2 files changed, 9 insertions, 31 deletions
diff --git a/arch/x86/coco/tdx/tdcall.S b/arch/x86/coco/tdx/tdcall.S index 2bd436a4790d..6a255e6809bc 100644 --- a/arch/x86/coco/tdx/tdcall.S +++ b/arch/x86/coco/tdx/tdcall.S @@ -37,6 +37,8 @@ ( TDX_RDX | TDX_RBX | TDX_RSI | TDX_RDI | TDX_R8 | TDX_R9 | \ TDX_R10 | TDX_R11 | TDX_R12 | TDX_R13 | TDX_R14 | TDX_R15 ) +.section .noinstr.text, "ax" + /* * __tdx_module_call() - Used by TDX guests to request services from * the TDX module (does not include VMM services) using TDCALL instruction. @@ -158,19 +160,6 @@ 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, 8(%rsp) - jz .Lskip_sti - sti -.Lskip_sti: tdcall /* diff --git a/arch/x86/coco/tdx/tdx.c b/arch/x86/coco/tdx/tdx.c index b593009b30ab..055300e08fb3 100644 --- a/arch/x86/coco/tdx/tdx.c +++ b/arch/x86/coco/tdx/tdx.c @@ -70,8 +70,9 @@ static inline u64 _tdx_hypercall(u64 fn, u64 r12, u64 r13, u64 r14, u64 r15) } /* Called from __tdx_hypercall() for unrecoverable failure */ -void __tdx_hypercall_failed(void) +noinstr void __tdx_hypercall_failed(void) { + instrumentation_begin(); panic("TDVMCALL failed. TDX module bug?"); } @@ -81,7 +82,7 @@ void __tdx_hypercall_failed(void) * Reusing the KVM EXIT_REASON macros makes it easier to connect the host and * guest sides of these calls. */ -static u64 hcall_func(u64 exit_reason) +static __always_inline u64 hcall_func(u64 exit_reason) { return exit_reason; } @@ -268,7 +269,7 @@ 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, @@ -288,20 +289,14 @@ 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); @@ -309,18 +304,12 @@ 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"); } |