diff options
Diffstat (limited to 'arch/x86/entry/entry_64.S')
| -rw-r--r-- | arch/x86/entry/entry_64.S | 76 |
1 files changed, 40 insertions, 36 deletions
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S index 42a4b652469d..d5c7f18f79ac 100644 --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -538,17 +538,48 @@ END(irq_entries_start) .endm /* - * Switch to the thread stack. This is called with the IRET frame and - * orig_ax on the stack. (That is, RDI..R12 are not on the stack and - * space has not been allocated for them.) + * Interrupt entry helper function. + * + * Entry runs with interrupts off. Stack layout at entry: + * +----------------------------------------------------+ + * | regs->ss | + * | regs->rsp | + * | regs->eflags | + * | regs->cs | + * | regs->ip | + * +----------------------------------------------------+ + * | regs->orig_ax = ~(interrupt number) | + * +----------------------------------------------------+ + * | return address | + * +----------------------------------------------------+ */ -.macro DO_SWITCH_TO_THREAD_STACK +ENTRY(interrupt_entry) + UNWIND_HINT_FUNC + ASM_CLAC + cld + + testb $3, CS-ORIG_RAX+8(%rsp) + jz 1f + SWAPGS + + /* + * Switch to the thread stack. The IRET frame and orig_ax are + * on the stack, as well as the return address. RDI..R12 are + * not (yet) on the stack and space has not (yet) been + * allocated for them. + */ pushq %rdi + /* Need to switch before accessing the thread stack. */ SWITCH_TO_KERNEL_CR3 scratch_reg=%rdi movq %rsp, %rdi movq PER_CPU_VAR(cpu_current_top_of_stack), %rsp - UNWIND_HINT sp_offset=16 sp_reg=ORC_REG_DI + + /* + * We have RDI, return address, and orig_ax on the stack on + * top of the IRET frame. That means offset=24 + */ + UNWIND_HINT_IRET_REGS base=%rdi offset=24 pushq 7*8(%rdi) /* regs->ss */ pushq 6*8(%rdi) /* regs->rsp */ @@ -560,25 +591,6 @@ END(irq_entries_start) UNWIND_HINT_FUNC movq (%rdi), %rdi -.endm - -/* - * Interrupt entry/exit. - * - * Interrupt entry points save only callee clobbered registers in fast path. - * - * Entry runs with interrupts off. - */ -/* 8(%rsp): ~(interrupt number) */ -ENTRY(interrupt_entry) - UNWIND_HINT_FUNC - ASM_CLAC - cld - - testb $3, CS-ORIG_RAX+8(%rsp) - jz 1f - SWAPGS - DO_SWITCH_TO_THREAD_STACK 1: PUSH_AND_CLEAR_REGS save_ret=1 @@ -592,7 +604,7 @@ ENTRY(interrupt_entry) * * We need to tell lockdep that IRQs are off. We can't do this until * we fix gsbase, and we should do it before enter_from_user_mode - * (which can take locks). Since TRACE_IRQS_OFF idempotent, + * (which can take locks). Since TRACE_IRQS_OFF is idempotent, * the simplest way to handle it is to just call it twice if * we enter from user mode. There's no reason to optimize this since * TRACE_IRQS_OFF is a no-op if lockdep is off. @@ -609,6 +621,9 @@ ENTRY(interrupt_entry) ret END(interrupt_entry) + +/* Interrupt entry/exit. */ + /* * The interrupt stubs push (~vector+0x80) onto the stack and * then jump to common_interrupt. @@ -878,17 +893,6 @@ apicinterrupt IRQ_WORK_VECTOR irq_work_interrupt smp_irq_work_interrupt */ #define CPU_TSS_IST(x) PER_CPU_VAR(cpu_tss_rw) + (TSS_ist + ((x) - 1) * 8) -#if defined(CONFIG_IA32_EMULATION) -/* entry_64_compat.S::entry_INT80_compat expects this to be an ASM function */ -ENTRY(switch_to_thread_stack) - UNWIND_HINT_FUNC - - DO_SWITCH_TO_THREAD_STACK - - ret -END(switch_to_thread_stack) -#endif - .macro idtentry sym do_sym has_error_code:req paranoid=0 shift_ist=-1 ENTRY(\sym) UNWIND_HINT_IRET_REGS offset=\has_error_code*8 |