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Reintroduce a workaround for a gas bug (misassembled lgdt instruction)

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Use .code16 for the real mode part of the AP bootstrap trampoline code.
This commit is contained in:
tegge 2000-05-25 21:33:52 +00:00
parent ac80812473
commit 055edbc9e3
2 changed files with 14 additions and 26 deletions
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20
sys/amd64/amd64/mpboot.S
View File

@ -165,20 +165,15 @@ NON_GPROF_ENTRY(wait_ap)
BOOTMP1:
NON_GPROF_ENTRY(bootMP)
.code16
cli
CHECKPOINT(0x34, 1)
/* First guarantee a 'clean slate' */
data32
xorl %eax, %eax
data32
movl %eax, %ebx
data32
movl %eax, %ecx
data32
movl %eax, %edx
data32
movl %eax, %esi
data32
movl %eax, %edi
/* set up data segments */
@ -188,17 +183,18 @@ NON_GPROF_ENTRY(bootMP)
mov %ax, %fs
mov %ax, %gs
mov %ax, %ss
mov $(boot_stk-_bootMP), %sp
mov $(boot_stk-_bootMP), %esp
/* Now load the global descriptor table */
addr32
data32
lgdt MP_GDTptr-_bootMP
/* XXX: sigh: lgdt MP_GDTptr-_bootMP GAS BUG! */
.byte 0x0f, 0x01, 0x15 /* XXX hand assemble! */
.long MP_GDTptr-_bootMP /* XXX hand assemble! */
/* Enable protected mode */
data32
movl %cr0, %eax
data32
orl $CR0_PE, %eax
data32
movl %eax, %cr0
@ -207,13 +203,11 @@ NON_GPROF_ENTRY(bootMP)
* make intrasegment jump to flush the processor pipeline and
* reload CS register
*/
data32
pushl $0x18
data32
pushl $(protmode-_bootMP)
data32
lret
lretl
.code32
protmode:
CHECKPOINT(0x35, 2)

20
sys/i386/i386/mpboot.s
View File

@ -165,20 +165,15 @@ NON_GPROF_ENTRY(wait_ap)
BOOTMP1:
NON_GPROF_ENTRY(bootMP)
.code16
cli
CHECKPOINT(0x34, 1)
/* First guarantee a 'clean slate' */
data32
xorl %eax, %eax
data32
movl %eax, %ebx
data32
movl %eax, %ecx
data32
movl %eax, %edx
data32
movl %eax, %esi
data32
movl %eax, %edi
/* set up data segments */
@ -188,17 +183,18 @@ NON_GPROF_ENTRY(bootMP)
mov %ax, %fs
mov %ax, %gs
mov %ax, %ss
mov $(boot_stk-_bootMP), %sp
mov $(boot_stk-_bootMP), %esp
/* Now load the global descriptor table */
addr32
data32
lgdt MP_GDTptr-_bootMP
/* XXX: sigh: lgdt MP_GDTptr-_bootMP GAS BUG! */
.byte 0x0f, 0x01, 0x15 /* XXX hand assemble! */
.long MP_GDTptr-_bootMP /* XXX hand assemble! */
/* Enable protected mode */
data32
movl %cr0, %eax
data32
orl $CR0_PE, %eax
data32
movl %eax, %cr0
@ -207,13 +203,11 @@ NON_GPROF_ENTRY(bootMP)
* make intrasegment jump to flush the processor pipeline and
* reload CS register
*/
data32
pushl $0x18
data32
pushl $(protmode-_bootMP)
data32
lret
lretl
.code32
protmode:
CHECKPOINT(0x35, 2)