diff options
Diffstat (limited to 'arch/x86/kernel/entry_64.S')
| -rw-r--r-- | arch/x86/kernel/entry_64.S | 101 |
1 files changed, 59 insertions, 42 deletions
diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S index e70f3881d7e4..bea8474744ff 100644 --- a/arch/x86/kernel/entry_64.S +++ b/arch/x86/kernel/entry_64.S @@ -50,6 +50,7 @@ #include <asm/hw_irq.h> #include <asm/page.h> #include <asm/irqflags.h> +#include <asm/paravirt.h> .code64 @@ -57,6 +58,13 @@ #define retint_kernel retint_restore_args #endif +#ifdef CONFIG_PARAVIRT +ENTRY(native_irq_enable_syscall_ret) + movq %gs:pda_oldrsp,%rsp + swapgs + sysretq +#endif /* CONFIG_PARAVIRT */ + .macro TRACE_IRQS_IRETQ offset=ARGOFFSET #ifdef CONFIG_TRACE_IRQFLAGS @@ -216,14 +224,21 @@ ENTRY(system_call) CFI_DEF_CFA rsp,PDA_STACKOFFSET CFI_REGISTER rip,rcx /*CFI_REGISTER rflags,r11*/ - swapgs + SWAPGS_UNSAFE_STACK + /* + * A hypervisor implementation might want to use a label + * after the swapgs, so that it can do the swapgs + * for the guest and jump here on syscall. + */ +ENTRY(system_call_after_swapgs) + movq %rsp,%gs:pda_oldrsp movq %gs:pda_kernelstack,%rsp /* * No need to follow this irqs off/on section - it's straight * and short: */ - sti + ENABLE_INTERRUPTS(CLBR_NONE) SAVE_ARGS 8,1 movq %rax,ORIG_RAX-ARGOFFSET(%rsp) movq %rcx,RIP-ARGOFFSET(%rsp) @@ -246,7 +261,7 @@ ret_from_sys_call: sysret_check: LOCKDEP_SYS_EXIT GET_THREAD_INFO(%rcx) - cli + DISABLE_INTERRUPTS(CLBR_NONE) TRACE_IRQS_OFF movl threadinfo_flags(%rcx),%edx andl %edi,%edx @@ -260,9 +275,7 @@ sysret_check: CFI_REGISTER rip,rcx RESTORE_ARGS 0,-ARG_SKIP,1 /*CFI_REGISTER rflags,r11*/ - movq %gs:pda_oldrsp,%rsp - swapgs - sysretq + ENABLE_INTERRUPTS_SYSCALL_RET CFI_RESTORE_STATE /* Handle reschedules */ @@ -271,7 +284,7 @@ sysret_careful: bt $TIF_NEED_RESCHED,%edx jnc sysret_signal TRACE_IRQS_ON - sti + ENABLE_INTERRUPTS(CLBR_NONE) pushq %rdi CFI_ADJUST_CFA_OFFSET 8 call schedule @@ -282,7 +295,7 @@ sysret_careful: /* Handle a signal */ sysret_signal: TRACE_IRQS_ON - sti + ENABLE_INTERRUPTS(CLBR_NONE) testl $_TIF_DO_NOTIFY_MASK,%edx jz 1f @@ -295,7 +308,7 @@ sysret_signal: 1: movl $_TIF_NEED_RESCHED,%edi /* Use IRET because user could have changed frame. This works because ptregscall_common has called FIXUP_TOP_OF_STACK. */ - cli + DISABLE_INTERRUPTS(CLBR_NONE) TRACE_IRQS_OFF jmp int_with_check @@ -327,7 +340,7 @@ tracesys: */ .globl int_ret_from_sys_call int_ret_from_sys_call: - cli + DISABLE_INTERRUPTS(CLBR_NONE) TRACE_IRQS_OFF testl $3,CS-ARGOFFSET(%rsp) je retint_restore_args @@ -349,20 +362,20 @@ int_careful: bt $TIF_NEED_RESCHED,%edx jnc int_very_careful TRACE_IRQS_ON - sti + ENABLE_INTERRUPTS(CLBR_NONE) pushq %rdi CFI_ADJUST_CFA_OFFSET 8 call schedule popq %rdi CFI_ADJUST_CFA_OFFSET -8 - cli + DISABLE_INTERRUPTS(CLBR_NONE) TRACE_IRQS_OFF jmp int_with_check /* handle signals and tracing -- both require a full stack frame */ int_very_careful: TRACE_IRQS_ON - sti + ENABLE_INTERRUPTS(CLBR_NONE) SAVE_REST /* Check for syscall exit trace */ testl $(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SINGLESTEP),%edx @@ -385,7 +398,7 @@ int_signal: 1: movl $_TIF_NEED_RESCHED,%edi int_restore_rest: RESTORE_REST - cli + DISABLE_INTERRUPTS(CLBR_NONE) TRACE_IRQS_OFF jmp int_with_check CFI_ENDPROC @@ -506,7 +519,7 @@ END(stub_rt_sigreturn) CFI_DEF_CFA_REGISTER rbp testl $3,CS(%rdi) je 1f - swapgs + SWAPGS /* irqcount is used to check if a CPU is already on an interrupt stack or not. While this is essentially redundant with preempt_count it is a little cheaper to use a separate counter in the PDA @@ -527,7 +540,7 @@ ENTRY(common_interrupt) interrupt do_IRQ /* 0(%rsp): oldrsp-ARGOFFSET */ ret_from_intr: - cli + DISABLE_INTERRUPTS(CLBR_NONE) TRACE_IRQS_OFF decl %gs:pda_irqcount leaveq @@ -556,13 +569,13 @@ retint_swapgs: /* return to user-space */ /* * The iretq could re-enable interrupts: */ - cli + DISABLE_INTERRUPTS(CLBR_ANY) TRACE_IRQS_IRETQ - swapgs + SWAPGS jmp restore_args retint_restore_args: /* return to kernel space */ - cli + DISABLE_INTERRUPTS(CLBR_ANY) /* * The iretq could re-enable interrupts: */ @@ -570,10 +583,14 @@ retint_restore_args: /* return to kernel space */ restore_args: RESTORE_ARGS 0,8,0 iret_label: +#ifdef CONFIG_PARAVIRT + INTERRUPT_RETURN +#endif +ENTRY(native_iret) iretq .section __ex_table,"a" - .quad iret_label,bad_iret + .quad native_iret, bad_iret .previous .section .fixup,"ax" /* force a signal here? this matches i386 behaviour */ @@ -581,24 +598,24 @@ iret_label: bad_iret: movq $11,%rdi /* SIGSEGV */ TRACE_IRQS_ON - sti - jmp do_exit - .previous - + ENABLE_INTERRUPTS(CLBR_ANY | ~(CLBR_RDI)) + jmp do_exit + .previous + /* edi: workmask, edx: work */ retint_careful: CFI_RESTORE_STATE bt $TIF_NEED_RESCHED,%edx jnc retint_signal TRACE_IRQS_ON - sti + ENABLE_INTERRUPTS(CLBR_NONE) pushq %rdi CFI_ADJUST_CFA_OFFSET 8 call schedule popq %rdi CFI_ADJUST_CFA_OFFSET -8 GET_THREAD_INFO(%rcx) - cli + DISABLE_INTERRUPTS(CLBR_NONE) TRACE_IRQS_OFF jmp retint_check @@ -606,14 +623,14 @@ retint_signal: testl $_TIF_DO_NOTIFY_MASK,%edx jz retint_swapgs TRACE_IRQS_ON - sti + ENABLE_INTERRUPTS(CLBR_NONE) SAVE_REST movq $-1,ORIG_RAX(%rsp) xorl %esi,%esi # oldset movq %rsp,%rdi # &pt_regs call do_notify_resume RESTORE_REST - cli + DISABLE_INTERRUPTS(CLBR_NONE) TRACE_IRQS_OFF movl $_TIF_NEED_RESCHED,%edi GET_THREAD_INFO(%rcx) @@ -731,7 +748,7 @@ END(spurious_interrupt) rdmsr testl %edx,%edx js 1f - swapgs + SWAPGS xorl %ebx,%ebx 1: .if \ist @@ -747,7 +764,7 @@ END(spurious_interrupt) .if \ist addq $EXCEPTION_STKSZ, per_cpu__init_tss + TSS_ist + (\ist - 1) * 8(%rbp) .endif - cli + DISABLE_INTERRUPTS(CLBR_NONE) .if \irqtrace TRACE_IRQS_OFF .endif @@ -776,10 +793,10 @@ paranoid_swapgs\trace: .if \trace TRACE_IRQS_IRETQ 0 .endif - swapgs + SWAPGS_UNSAFE_STACK paranoid_restore\trace: RESTORE_ALL 8 - iretq + INTERRUPT_RETURN paranoid_userspace\trace: GET_THREAD_INFO(%rcx) movl threadinfo_flags(%rcx),%ebx @@ -794,11 +811,11 @@ paranoid_userspace\trace: .if \trace TRACE_IRQS_ON .endif - sti + ENABLE_INTERRUPTS(CLBR_NONE) xorl %esi,%esi /* arg2: oldset */ movq %rsp,%rdi /* arg1: &pt_regs */ call do_notify_resume - cli + DISABLE_INTERRUPTS(CLBR_NONE) .if \trace TRACE_IRQS_OFF .endif @@ -807,9 +824,9 @@ paranoid_schedule\trace: .if \trace TRACE_IRQS_ON .endif - sti + ENABLE_INTERRUPTS(CLBR_ANY) call schedule - cli + DISABLE_INTERRUPTS(CLBR_ANY) .if \trace TRACE_IRQS_OFF .endif @@ -862,7 +879,7 @@ KPROBE_ENTRY(error_entry) testl $3,CS(%rsp) je error_kernelspace error_swapgs: - swapgs + SWAPGS error_sti: movq %rdi,RDI(%rsp) CFI_REL_OFFSET rdi,RDI @@ -874,7 +891,7 @@ error_sti: error_exit: movl %ebx,%eax RESTORE_REST - cli + DISABLE_INTERRUPTS(CLBR_NONE) TRACE_IRQS_OFF GET_THREAD_INFO(%rcx) testl %eax,%eax @@ -911,12 +928,12 @@ ENTRY(load_gs_index) CFI_STARTPROC pushf CFI_ADJUST_CFA_OFFSET 8 - cli - swapgs + DISABLE_INTERRUPTS(CLBR_ANY | ~(CLBR_RDI)) + SWAPGS gs_change: movl %edi,%gs 2: mfence /* workaround */ - swapgs + SWAPGS popf CFI_ADJUST_CFA_OFFSET -8 ret @@ -930,7 +947,7 @@ ENDPROC(load_gs_index) .section .fixup,"ax" /* running with kernelgs */ bad_gs: - swapgs /* switch back to user gs */ + SWAPGS /* switch back to user gs */ xorl %eax,%eax movl %eax,%gs jmp 2b |