diff options
Diffstat (limited to 'arch/x86/kernel/entry_32.S')
| -rw-r--r-- | arch/x86/kernel/entry_32.S | 52 |
1 files changed, 27 insertions, 25 deletions
diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S index 4b87c32..2a609dc 100644 --- a/arch/x86/kernel/entry_32.S +++ b/arch/x86/kernel/entry_32.S @@ -1,5 +1,4 @@ /* - * linux/arch/i386/entry.S * * Copyright (C) 1991, 1992 Linus Torvalds */ @@ -51,6 +50,7 @@ #include <asm/desc.h> #include <asm/percpu.h> #include <asm/dwarf2.h> +#include <asm/processor-flags.h> #include "irq_vectors.h" /* @@ -68,13 +68,6 @@ #define nr_syscalls ((syscall_table_size)/4) -CF_MASK = 0x00000001 -TF_MASK = 0x00000100 -IF_MASK = 0x00000200 -DF_MASK = 0x00000400 -NT_MASK = 0x00004000 -VM_MASK = 0x00020000 - #ifdef CONFIG_PREEMPT #define preempt_stop(clobbers) DISABLE_INTERRUPTS(clobbers); TRACE_IRQS_OFF #else @@ -84,7 +77,7 @@ VM_MASK = 0x00020000 .macro TRACE_IRQS_IRET #ifdef CONFIG_TRACE_IRQFLAGS - testl $IF_MASK,PT_EFLAGS(%esp) # interrupts off? + testl $X86_EFLAGS_IF,PT_EFLAGS(%esp) # interrupts off? jz 1f TRACE_IRQS_ON 1: @@ -246,7 +239,7 @@ ret_from_intr: check_userspace: movl PT_EFLAGS(%esp), %eax # mix EFLAGS and CS movb PT_CS(%esp), %al - andl $(VM_MASK | SEGMENT_RPL_MASK), %eax + andl $(X86_EFLAGS_VM | SEGMENT_RPL_MASK), %eax cmpl $USER_RPL, %eax jb resume_kernel # not returning to v8086 or userspace @@ -271,7 +264,7 @@ need_resched: movl TI_flags(%ebp), %ecx # need_resched set ? testb $_TIF_NEED_RESCHED, %cl jz restore_all - testl $IF_MASK,PT_EFLAGS(%esp) # interrupts off (exception path) ? + testl $X86_EFLAGS_IF,PT_EFLAGS(%esp) # interrupts off (exception path) ? jz restore_all call preempt_schedule_irq jmp need_resched @@ -291,10 +284,10 @@ ENTRY(ia32_sysenter_target) movl TSS_sysenter_sp0(%esp),%esp sysenter_past_esp: /* - * No need to follow this irqs on/off section: the syscall - * disabled irqs and here we enable it straight after entry: + * Interrupts are disabled here, but we can't trace it until + * enough kernel state to call TRACE_IRQS_OFF can be called - but + * we immediately enable interrupts at that point anyway. */ - ENABLE_INTERRUPTS(CLBR_NONE) pushl $(__USER_DS) CFI_ADJUST_CFA_OFFSET 4 /*CFI_REL_OFFSET ss, 0*/ @@ -302,6 +295,7 @@ sysenter_past_esp: CFI_ADJUST_CFA_OFFSET 4 CFI_REL_OFFSET esp, 0 pushfl + orl $X86_EFLAGS_IF, (%esp) CFI_ADJUST_CFA_OFFSET 4 pushl $(__USER_CS) CFI_ADJUST_CFA_OFFSET 4 @@ -315,6 +309,11 @@ sysenter_past_esp: CFI_ADJUST_CFA_OFFSET 4 CFI_REL_OFFSET eip, 0 + pushl %eax + CFI_ADJUST_CFA_OFFSET 4 + SAVE_ALL + ENABLE_INTERRUPTS(CLBR_NONE) + /* * Load the potential sixth argument from user stack. * Careful about security. @@ -322,14 +321,12 @@ sysenter_past_esp: cmpl $__PAGE_OFFSET-3,%ebp jae syscall_fault 1: movl (%ebp),%ebp + movl %ebp,PT_EBP(%esp) .section __ex_table,"a" .align 4 .long 1b,syscall_fault .previous - pushl %eax - CFI_ADJUST_CFA_OFFSET 4 - SAVE_ALL GET_THREAD_INFO(%ebp) /* Note, _TIF_SECCOMP is bit number 8, and so it needs testw and not testb */ @@ -384,7 +381,7 @@ syscall_exit: # setting need_resched or sigpending # between sampling and the iret TRACE_IRQS_OFF - testl $TF_MASK,PT_EFLAGS(%esp) # If tracing set singlestep flag on exit + testl $X86_EFLAGS_TF,PT_EFLAGS(%esp) # If tracing set singlestep flag on exit jz no_singlestep orl $_TIF_SINGLESTEP,TI_flags(%ebp) no_singlestep: @@ -399,7 +396,7 @@ restore_all: # See comments in process.c:copy_thread() for details. movb PT_OLDSS(%esp), %ah movb PT_CS(%esp), %al - andl $(VM_MASK | (SEGMENT_TI_MASK << 8) | SEGMENT_RPL_MASK), %eax + andl $(X86_EFLAGS_VM | (SEGMENT_TI_MASK << 8) | SEGMENT_RPL_MASK), %eax cmpl $((SEGMENT_LDT << 8) | USER_RPL), %eax CFI_REMEMBER_STATE je ldt_ss # returning to user-space with LDT SS @@ -412,7 +409,7 @@ restore_nocheck_notrace: irq_return: INTERRUPT_RETURN .section .fixup,"ax" -iret_exc: +ENTRY(iret_exc) pushl $0 # no error code pushl $do_iret_error jmp error_code @@ -486,7 +483,7 @@ work_resched: work_notifysig: # deal with pending signals and # notify-resume requests #ifdef CONFIG_VM86 - testl $VM_MASK, PT_EFLAGS(%esp) + testl $X86_EFLAGS_VM, PT_EFLAGS(%esp) movl %esp, %eax jne work_notifysig_v86 # returning to kernel-space or # vm86-space @@ -543,9 +540,6 @@ END(syscall_exit_work) RING0_INT_FRAME # can't unwind into user space anyway syscall_fault: - pushl %eax # save orig_eax - CFI_ADJUST_CFA_OFFSET 4 - SAVE_ALL GET_THREAD_INFO(%ebp) movl $-EFAULT,PT_EAX(%esp) jmp resume_userspace @@ -1023,6 +1017,13 @@ ENTRY(kernel_thread_helper) ENDPROC(kernel_thread_helper) #ifdef CONFIG_XEN +/* Xen doesn't set %esp to be precisely what the normal sysenter + entrypoint expects, so fix it up before using the normal path. */ +ENTRY(xen_sysenter_target) + RING0_INT_FRAME + addl $5*4, %esp /* remove xen-provided frame */ + jmp sysenter_past_esp + ENTRY(xen_hypervisor_callback) CFI_STARTPROC pushl $0 @@ -1041,8 +1042,9 @@ ENTRY(xen_hypervisor_callback) cmpl $xen_iret_end_crit,%eax jae 1f - call xen_iret_crit_fixup + jmp xen_iret_crit_fixup +ENTRY(xen_do_upcall) 1: mov %esp, %eax call xen_evtchn_do_upcall jmp ret_from_intr |