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Revert "[PATCH] paravirt: Add startup infrastructure for paravirtualization" 

This reverts commit c9ccf30d77.

Entering the kernel at startup_32 without passing our real mode data in
%esi, and without guaranteeing that physical and virtual addresses are
identity mapped makes head.S impossible to maintain.

The only user of this infrastructure is lguest which is not merged so
nothing we currently support will break by removing this over designed
nightmare, and only the pending lguest patches will be affected.  The
pending Xen patches have a different entry point that they use.

We are currently discussing what Xen and lguest need to do to boot the
kernel in a more normal fashion so using startup_32 in this weird manner is
clearly not their long term direction.

So let's remove this code in head.S before it causes brain damage to people
trying to maintain head.S

Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Andi Kleen <ak@suse.de>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Zachary Amsden <zach@vmware.com>
CC: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Eric W. Biederman 2007-05-10 03:15:36 -07:00 committed by Linus Torvalds
parent 0cfe61e1a7
commit 5a18c92aab
4 changed files with 0 additions and 50 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

38
arch/i386/kernel/head.S
View File

@ -71,12 +71,6 @@ INIT_MAP_BEYOND_END = BOOTBITMAP_SIZE + (PAGE_TABLE_SIZE + ALLOCATOR_SLOP)*PAGE_
.section .text.head,"ax",@progbits .section .text.head,"ax",@progbits
ENTRY(startup_32) ENTRY(startup_32)
#ifdef CONFIG_PARAVIRT
movl %cs, %eax
testl $0x3, %eax
jnz startup_paravirt
#endif
/* /*
* Set segments to known values. * Set segments to known values.
*/ */
@ -501,38 +495,6 @@ ignore_int:
iret iret
.section .text .section .text
#ifdef CONFIG_PARAVIRT
startup_paravirt:
cld
movl $(init_thread_union+THREAD_SIZE),%esp
/* We take pains to preserve all the regs. */
pushl %edx
pushl %ecx
pushl %eax
pushl $__start_paravirtprobe
1:
movl 0(%esp), %eax
cmpl $__stop_paravirtprobe, %eax
je unhandled_paravirt
pushl (%eax)
movl 8(%esp), %eax
call *(%esp)
popl %eax
movl 4(%esp), %eax
movl 8(%esp), %ecx
movl 12(%esp), %edx
addl $4, (%esp)
jmp 1b
unhandled_paravirt:
/* Nothing wanted us: we're screwed. */
ud2
#endif
/* /*
* Real beginning of normal "text" segment * Real beginning of normal "text" segment
*/ */

1
arch/i386/kernel/paravirt.c
View File

@ -19,7 +19,6 @@
#include <linux/module.h> #include <linux/module.h>
#include <linux/efi.h> #include <linux/efi.h>
#include <linux/bcd.h> #include <linux/bcd.h>
#include <linux/start_kernel.h>
#include <linux/highmem.h> #include <linux/highmem.h>
#include <asm/bug.h> #include <asm/bug.h>

6
arch/i386/kernel/vmlinux.lds.S
View File

@ -78,12 +78,6 @@ SECTIONS
CONSTRUCTORS CONSTRUCTORS
} :data } :data
.paravirtprobe : AT(ADDR(.paravirtprobe) - LOAD_OFFSET) {
__start_paravirtprobe = .;
*(.paravirtprobe)
__stop_paravirtprobe = .;
}
. = ALIGN(4096); . = ALIGN(4096);
.data_nosave : AT(ADDR(.data_nosave) - LOAD_OFFSET) { .data_nosave : AT(ADDR(.data_nosave) - LOAD_OFFSET) {
__nosave_begin = .; __nosave_begin = .;

5
include/asm-i386/paravirt.h
View File

@ -222,11 +222,6 @@ struct paravirt_ops
void (*iret)(void); void (*iret)(void);
}; };
/* Mark a paravirt probe function. */
#define paravirt_probe(fn) \
static asmlinkage void (*__paravirtprobe_##fn)(void) __attribute_used__ \
__attribute__((__section__(".paravirtprobe"))) = fn
extern struct paravirt_ops paravirt_ops; extern struct paravirt_ops paravirt_ops;
#define PARAVIRT_PATCH(x) \ #define PARAVIRT_PATCH(x) \