diff options
Diffstat (limited to 'arch/x86/entry/entry_64.S')
-rw-r--r-- | arch/x86/entry/entry_64.S | 20 |
1 files changed, 4 insertions, 16 deletions
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S index d58d8dcb824531..76c1d85e749bc7 100644 --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -774,7 +774,7 @@ ENTRY(\sym) call \do_sym - jmp error_exit /* %ebx: no swapgs flag */ + jmp error_exit .endif END(\sym) .endm @@ -1043,7 +1043,6 @@ END(paranoid_exit) /* * Save all registers in pt_regs, and switch gs if needed. - * Return: EBX=0: came from user mode; EBX=1: otherwise */ ENTRY(error_entry) cld @@ -1056,7 +1055,6 @@ ENTRY(error_entry) * the kernel CR3 here. */ SWITCH_KERNEL_CR3 - xorl %ebx, %ebx testb $3, CS+8(%rsp) jz .Lerror_kernelspace @@ -1087,7 +1085,6 @@ ENTRY(error_entry) * for these here too. */ .Lerror_kernelspace: - incl %ebx leaq native_irq_return_iret(%rip), %rcx cmpq %rcx, RIP+8(%rsp) je .Lerror_bad_iret @@ -1119,28 +1116,19 @@ ENTRY(error_entry) /* * Pretend that the exception came from user mode: set up pt_regs - * as if we faulted immediately after IRET and clear EBX so that - * error_exit knows that we will be returning to user mode. + * as if we faulted immediately after IRET. */ mov %rsp, %rdi call fixup_bad_iret mov %rax, %rsp - decl %ebx jmp .Lerror_entry_from_usermode_after_swapgs END(error_entry) - -/* - * On entry, EBX is a "return to kernel mode" flag: - * 1: already in kernel mode, don't need SWAPGS - * 0: user gsbase is loaded, we need SWAPGS and standard preparation for return to usermode - */ ENTRY(error_exit) - movl %ebx, %eax DISABLE_INTERRUPTS(CLBR_NONE) TRACE_IRQS_OFF - testl %eax, %eax - jnz retint_kernel + testb $3, CS(%rsp) + jz retint_kernel jmp retint_user END(error_exit) |