Minor cleanups found while fixing a bug involving double mapping of low

memory:

Load the kernel eflags less magically, as in locore.  The magic increased
when I removed eflags from the pcb in r305899.

Remove a jump to low memory that became garbage when the i386 version was
mostly replaced by the amd64 version in r235622.

The amd64 version is very similar.  It still loads the flags magically,
but is not missing comments about using the special page table.

Reviewed by:	kib
This commit is contained in:
Bruce Evans 2017-12-15 03:05:14 +00:00
parent f1db5ef7aa
commit c93ea91c54
Notes: svn2git 2020-12-20 02:59:44 +00:00
svn path=/head/; revision=326867

View File

@ -50,17 +50,19 @@
.code16
wakeup_start:
/*
* Set up segment registers for real mode, a small stack for
* any calls we make, and clear any flags.
* Set up segment registers for real mode and a small stack for
* any calls we make. Set up full 32-bit bootstrap kernel flags
* since resumectx() doesn't restore flags. PSL_KERNEL gives
* bootstrap kernel flags (with interrupts disabled), not normal
* kernel flags.
*/
cli /* make sure no interrupts */
mov %cs, %ax /* copy %cs to %ds. Remember these */
mov %ax, %ds /* are offsets rather than selectors */
mov %ax, %ss
movw $PAGE_SIZE, %sp
xorw %ax, %ax
pushw %ax
popfw
pushl $PSL_KERNEL
popfl
/* To debug resume hangs, beep the speaker if the user requested. */
testb $~0, resume_beep - wakeup_start
@ -156,8 +158,6 @@ wakeup_32:
orl $CR0_PG, %eax
mov %eax, %cr0
jmp 1f
1:
/* Jump to return address. */
jmp *%edx