* [PATCH v13 1/9] x86: add multiboot2 protocol support
2017-01-25 22:11 [PATCH v13 0/9] x86: multiboot2 protocol support Daniel Kiper
@ 2017-01-25 22:11 ` Daniel Kiper
2017-01-25 22:11 ` [PATCH v13 2/9] efi: build xen.gz with EFI code Daniel Kiper
` (7 subsequent siblings)
8 siblings, 0 replies; 15+ messages in thread
From: Daniel Kiper @ 2017-01-25 22:11 UTC (permalink / raw)
To: xen-devel
Cc: jgross, sstabellini, andrew.cooper3, cardoe, pgnet.dev, ning.sun,
julien.grall, jbeulich, qiaowei.ren, gang.wei, fu.wei
Add multiboot2 protocol support. Alter min memory limit handling as we
now may not find it from either multiboot (v1) or multiboot2.
This way we are laying the foundation for EFI + GRUB2 + Xen development.
Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Doug Goldstein <cardoe@cardoe.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Tested-by: Doug Goldstein <cardoe@cardoe.com>
---
v13 - suggestions/fixes:
- add Emacs file-local variables
(suggested by Andrew Cooper).
v12 - suggestions/fixes:
- replace TABs with spaces in xen/include/xen/multiboot2.h
(suggested by Doug Goldstein).
v9 - suggestions/fixes:
- use .L label instead of numeric one in multiboot2 data scanning loop;
I hope that this change does not invalidate Jan's Reviewed-by
(suggested by Jan Beulich).
v8 - suggestions/fixes:
- use sizeof(<var>/<expr>) instead of sizeof(<type>)
if it is possible
(suggested by Jan Beulich).
v7 - suggestions/fixes:
- rename mbi_mbi/mbi2_mbi to mbi_reloc/mbi2_reloc respectively
(suggested by Jan Beulich),
- initialize mbi_out->flags using "|=" instead of "="
(suggested by Jan Beulich),
- use sizeof(*mmap_dst) instead of sizeof(memory_map_t)
if it makes sense
(suggested by Jan Beulich).
v6 - suggestions/fixes:
- properly index multiboot2_tag_mmap_t.entries[]
(suggested by Jan Beulich),
- do not index mbi_out_mods[] beyond its end
(suggested by Andrew Cooper),
- reduce number of casts
(suggested by Andrew Cooper and Jan Beulich),
- add braces to increase code readability
(suggested by Andrew Cooper).
v5 - suggestions/fixes:
- check multiboot2_tag_mmap_t.entry_size before
multiboot2_tag_mmap_t.entries[] use
(suggested by Jan Beulich),
- properly index multiboot2_tag_mmap_t.entries[]
(suggested by Jan Beulich),
- use "type name[]" instad of "type name[0]"
in xen/include/xen/multiboot2.h
(suggested by Jan Beulich),
- remove unneeded comment
(suggested by Jan Beulich).
v4 - suggestions/fixes:
- avoid assembly usage in xen/arch/x86/boot/reloc.c,
- fix boundary check issue and optimize
for() loops in mbi2_mbi(),
- move to stdcall calling convention,
- remove unneeded typeof() from ALIGN_UP() macro
(suggested by Jan Beulich),
- add and use NULL definition in xen/arch/x86/boot/reloc.c
(suggested by Jan Beulich),
- do not read data beyond the end of multiboot2
information in xen/arch/x86/boot/head.S
(suggested by Jan Beulich),
- add :req to some .macro arguments
(suggested by Jan Beulich),
- use cmovcc if possible,
- add .L to multiboot2_header_end label
(suggested by Jan Beulich),
- add .L to multiboot2_proto label
(suggested by Jan Beulich),
- improve label names
(suggested by Jan Beulich).
v3 - suggestions/fixes:
- reorder reloc() arguments
(suggested by Jan Beulich),
- remove .L from multiboot2 header labels
(suggested by Andrew Cooper, Jan Beulich and Konrad Rzeszutek Wilk),
- take into account alignment when skipping multiboot2 fixed part
(suggested by Konrad Rzeszutek Wilk),
- create modules data if modules count != 0
(suggested by Jan Beulich),
- improve macros
(suggested by Jan Beulich),
- reduce number of casts
(suggested by Jan Beulich),
- use const if possible
(suggested by Jan Beulich),
- drop static and __used__ attribute from reloc()
(suggested by Jan Beulich),
- remove isolated/stray __packed attribute from
multiboot2_memory_map_t type definition
(suggested by Jan Beulich),
- reformat xen/include/xen/multiboot2.h
(suggested by Konrad Rzeszutek Wilk),
- improve comments
(suggested by Konrad Rzeszutek Wilk),
- remove hard tabs
(suggested by Jan Beulich and Konrad Rzeszutek Wilk).
v2 - suggestions/fixes:
- generate multiboot2 header using macros
(suggested by Jan Beulich),
- improve comments
(suggested by Jan Beulich),
- simplify assembly in xen/arch/x86/boot/head.S
(suggested by Jan Beulich),
- do not include include/xen/compiler.h
in xen/arch/x86/boot/reloc.c
(suggested by Jan Beulich),
- do not read data beyond the end of multiboot2 information
(suggested by Jan Beulich).
v2 - not fixed yet:
- dynamic dependency generation for xen/arch/x86/boot/reloc.S;
this requires more work; I am not sure that it pays because
potential patch requires more changes than addition of just
multiboot2.h to Makefile
(suggested by Jan Beulich),
- isolated/stray __packed attribute usage for multiboot2_memory_map_t
(suggested by Jan Beulich).
---
xen/arch/x86/boot/Makefile | 3 +-
xen/arch/x86/boot/head.S | 107 ++++++++++++++++++++++-
xen/arch/x86/boot/reloc.c | 154 +++++++++++++++++++++++++++++++--
xen/arch/x86/x86_64/asm-offsets.c | 9 ++
xen/include/xen/multiboot2.h | 169 +++++++++++++++++++++++++++++++++++++
5 files changed, 432 insertions(+), 10 deletions(-)
create mode 100644 xen/include/xen/multiboot2.h
diff --git a/xen/arch/x86/boot/Makefile b/xen/arch/x86/boot/Makefile
index 6d20646..c6246c8 100644
--- a/xen/arch/x86/boot/Makefile
+++ b/xen/arch/x86/boot/Makefile
@@ -4,7 +4,8 @@ DEFS_H_DEPS = defs.h $(BASEDIR)/include/xen/stdbool.h
CMDLINE_DEPS = $(DEFS_H_DEPS) video.h
-RELOC_DEPS = $(DEFS_H_DEPS) $(BASEDIR)/include/xen/multiboot.h
+RELOC_DEPS = $(DEFS_H_DEPS) $(BASEDIR)/include/xen/multiboot.h \
+ $(BASEDIR)/include/xen/multiboot2.h
head.o: cmdline.S reloc.S
diff --git a/xen/arch/x86/boot/head.S b/xen/arch/x86/boot/head.S
index 126e2e2..84cf44d 100644
--- a/xen/arch/x86/boot/head.S
+++ b/xen/arch/x86/boot/head.S
@@ -1,5 +1,6 @@
#include <xen/config.h>
#include <xen/multiboot.h>
+#include <xen/multiboot2.h>
#include <public/xen.h>
#include <asm/asm_defns.h>
#include <asm/desc.h>
@@ -19,6 +20,28 @@
#define BOOT_PSEUDORM_CS 0x0020
#define BOOT_PSEUDORM_DS 0x0028
+#define MB2_HT(name) (MULTIBOOT2_HEADER_TAG_##name)
+#define MB2_TT(name) (MULTIBOOT2_TAG_TYPE_##name)
+
+ .macro mb2ht_args arg:req, args:vararg
+ .long \arg
+ .ifnb \args
+ mb2ht_args \args
+ .endif
+ .endm
+
+ .macro mb2ht_init type:req, req:req, args:vararg
+ .align MULTIBOOT2_TAG_ALIGN
+.Lmb2ht_init_start\@:
+ .short \type
+ .short \req
+ .long .Lmb2ht_init_end\@ - .Lmb2ht_init_start\@
+ .ifnb \args
+ mb2ht_args \args
+ .endif
+.Lmb2ht_init_end\@:
+ .endm
+
ENTRY(start)
jmp __start
@@ -34,6 +57,42 @@ multiboot1_header_start: /*** MULTIBOOT1 HEADER ****/
.long -(MULTIBOOT_HEADER_MAGIC + MULTIBOOT_HEADER_FLAGS)
multiboot1_header_end:
+/*** MULTIBOOT2 HEADER ****/
+/* Some ideas are taken from grub-2.00/grub-core/tests/boot/kernel-i386.S file. */
+ .align MULTIBOOT2_HEADER_ALIGN
+
+multiboot2_header_start:
+ /* Magic number indicating a Multiboot2 header. */
+ .long MULTIBOOT2_HEADER_MAGIC
+ /* Architecture: i386. */
+ .long MULTIBOOT2_ARCHITECTURE_I386
+ /* Multiboot2 header length. */
+ .long .Lmultiboot2_header_end - multiboot2_header_start
+ /* Multiboot2 header checksum. */
+ .long -(MULTIBOOT2_HEADER_MAGIC + MULTIBOOT2_ARCHITECTURE_I386 + \
+ (.Lmultiboot2_header_end - multiboot2_header_start))
+
+ /* Multiboot2 information request tag. */
+ mb2ht_init MB2_HT(INFORMATION_REQUEST), MB2_HT(REQUIRED), \
+ MB2_TT(BASIC_MEMINFO), MB2_TT(MMAP)
+
+ /* Align modules at page boundry. */
+ mb2ht_init MB2_HT(MODULE_ALIGN), MB2_HT(REQUIRED)
+
+ /* Console flags tag. */
+ mb2ht_init MB2_HT(CONSOLE_FLAGS), MB2_HT(OPTIONAL), \
+ MULTIBOOT2_CONSOLE_FLAGS_EGA_TEXT_SUPPORTED
+
+ /* Framebuffer tag. */
+ mb2ht_init MB2_HT(FRAMEBUFFER), MB2_HT(OPTIONAL), \
+ 0, /* Number of the columns - no preference. */ \
+ 0, /* Number of the lines - no preference. */ \
+ 0 /* Number of bits per pixel - no preference. */
+
+ /* Multiboot2 header end tag. */
+ mb2ht_init MB2_HT(END), MB2_HT(REQUIRED)
+.Lmultiboot2_header_end:
+
.section .init.rodata, "a", @progbits
.align 4
@@ -82,10 +141,52 @@ __start:
mov %ecx,%es
mov %ecx,%ss
- /* Check for Multiboot bootloader */
+ /* Bootloaders may set multiboot{1,2}.mem_lower to a nonzero value. */
+ xor %edx,%edx
+
+ /* Check for Multiboot2 bootloader. */
+ cmp $MULTIBOOT2_BOOTLOADER_MAGIC,%eax
+ je .Lmultiboot2_proto
+
+ /* Check for Multiboot bootloader. */
cmp $MULTIBOOT_BOOTLOADER_MAGIC,%eax
jne not_multiboot
+ /* Get mem_lower from Multiboot information. */
+ testb $MBI_MEMLIMITS,MB_flags(%ebx)
+
+ /* Not available? BDA value will be fine. */
+ cmovnz MB_mem_lower(%ebx),%edx
+ jmp trampoline_setup
+
+.Lmultiboot2_proto:
+ /* Skip Multiboot2 information fixed part. */
+ lea (MB2_fixed_sizeof+MULTIBOOT2_TAG_ALIGN-1)(%ebx),%ecx
+ and $~(MULTIBOOT2_TAG_ALIGN-1),%ecx
+
+.Lmb2_tsize:
+ /* Check Multiboot2 information total size. */
+ mov %ecx,%edi
+ sub %ebx,%edi
+ cmp %edi,MB2_fixed_total_size(%ebx)
+ jbe trampoline_setup
+
+ /* Get mem_lower from Multiboot2 information. */
+ cmpl $MULTIBOOT2_TAG_TYPE_BASIC_MEMINFO,MB2_tag_type(%ecx)
+ cmove MB2_mem_lower(%ecx),%edx
+ je trampoline_setup
+
+ /* Is it the end of Multiboot2 information? */
+ cmpl $MULTIBOOT2_TAG_TYPE_END,MB2_tag_type(%ecx)
+ je trampoline_setup
+
+ /* Go to next Multiboot2 information tag. */
+ add MB2_tag_size(%ecx),%ecx
+ add $(MULTIBOOT2_TAG_ALIGN-1),%ecx
+ and $~(MULTIBOOT2_TAG_ALIGN-1),%ecx
+ jmp .Lmb2_tsize
+
+trampoline_setup:
/* Set up trampoline segment 64k below EBDA */
movzwl 0x40e,%ecx /* EBDA segment */
cmp $0xa000,%ecx /* sanity check (high) */
@@ -100,9 +201,6 @@ __start:
* Compare the value in the BDA with the information from the
* multiboot structure (if available) and use the smallest.
*/
- testb $MBI_MEMLIMITS,(%ebx)
- jz 2f /* not available? BDA value will be fine */
- mov MB_mem_lower(%ebx),%edx
cmp $0x100,%edx /* is the multiboot value too small? */
jb 2f /* if so, do not use it */
shl $10-4,%edx
@@ -121,6 +219,7 @@ __start:
mov $sym_phys(cpu0_stack)+1024,%esp
push %ecx /* Boot trampoline address. */
push %ebx /* Multiboot information address. */
+ push %eax /* Multiboot magic. */
call reloc
mov %eax,sym_phys(multiboot_ptr)
diff --git a/xen/arch/x86/boot/reloc.c b/xen/arch/x86/boot/reloc.c
index 91405e9..91fab9d 100644
--- a/xen/arch/x86/boot/reloc.c
+++ b/xen/arch/x86/boot/reloc.c
@@ -5,15 +5,18 @@
* and modules. This is most easily done early with paging disabled.
*
* Copyright (c) 2009, Citrix Systems, Inc.
+ * Copyright (c) 2013-2016 Oracle and/or its affiliates. All rights reserved.
*
* Authors:
* Keir Fraser <keir@xen.org>
+ * Daniel Kiper <daniel.kiper@oracle.com>
*/
/*
* This entry point is entered from xen/arch/x86/boot/head.S with:
- * - 0x4(%esp) = MULTIBOOT_INFORMATION_ADDRESS,
- * - 0x8(%esp) = BOOT_TRAMPOLINE_ADDRESS.
+ * - 0x4(%esp) = MULTIBOOT_MAGIC,
+ * - 0x8(%esp) = MULTIBOOT_INFORMATION_ADDRESS,
+ * - 0xc(%esp) = BOOT_TRAMPOLINE_ADDRESS.
*/
asm (
" .text \n"
@@ -24,6 +27,10 @@ asm (
#include "defs.h"
#include "../../../include/xen/multiboot.h"
+#include "../../../include/xen/multiboot2.h"
+
+#define get_mb2_data(tag, type, member) (((multiboot2_tag_##type##_t *)(tag))->member)
+#define get_mb2_string(tag, type, member) ((u32)get_mb2_data(tag, type, member))
static u32 alloc;
@@ -32,6 +39,12 @@ static u32 alloc_mem(u32 bytes)
return alloc -= ALIGN_UP(bytes, 16);
}
+static void zero_mem(u32 s, u32 bytes)
+{
+ while ( bytes-- )
+ *(char *)s++ = 0;
+}
+
static u32 copy_mem(u32 src, u32 bytes)
{
u32 dst, dst_ret;
@@ -58,13 +71,11 @@ static u32 copy_string(u32 src)
return copy_mem(src, p - src + 1);
}
-multiboot_info_t __stdcall *reloc(u32 mbi_in, u32 trampoline)
+static multiboot_info_t *mbi_reloc(u32 mbi_in)
{
int i;
multiboot_info_t *mbi_out;
- alloc = trampoline;
-
mbi_out = _p(copy_mem(mbi_in, sizeof(*mbi_out)));
if ( mbi_out->flags & MBI_CMDLINE )
@@ -101,3 +112,136 @@ multiboot_info_t __stdcall *reloc(u32 mbi_in, u32 trampoline)
return mbi_out;
}
+
+static multiboot_info_t *mbi2_reloc(u32 mbi_in)
+{
+ const multiboot2_fixed_t *mbi_fix = _p(mbi_in);
+ const multiboot2_memory_map_t *mmap_src;
+ const multiboot2_tag_t *tag;
+ module_t *mbi_out_mods = NULL;
+ memory_map_t *mmap_dst;
+ multiboot_info_t *mbi_out;
+ u32 ptr;
+ unsigned int i, mod_idx = 0;
+
+ ptr = alloc_mem(sizeof(*mbi_out));
+ mbi_out = _p(ptr);
+ zero_mem(ptr, sizeof(*mbi_out));
+
+ /* Skip Multiboot2 information fixed part. */
+ ptr = ALIGN_UP(mbi_in + sizeof(*mbi_fix), MULTIBOOT2_TAG_ALIGN);
+
+ /* Get the number of modules. */
+ for ( tag = _p(ptr); (u32)tag - mbi_in < mbi_fix->total_size;
+ tag = _p(ALIGN_UP((u32)tag + tag->size, MULTIBOOT2_TAG_ALIGN)) )
+ {
+ if ( tag->type == MULTIBOOT2_TAG_TYPE_MODULE )
+ ++mbi_out->mods_count;
+ else if ( tag->type == MULTIBOOT2_TAG_TYPE_END )
+ break;
+ }
+
+ if ( mbi_out->mods_count )
+ {
+ mbi_out->flags |= MBI_MODULES;
+ mbi_out->mods_addr = alloc_mem(mbi_out->mods_count * sizeof(*mbi_out_mods));
+ mbi_out_mods = _p(mbi_out->mods_addr);
+ }
+
+ /* Skip Multiboot2 information fixed part. */
+ ptr = ALIGN_UP(mbi_in + sizeof(*mbi_fix), MULTIBOOT2_TAG_ALIGN);
+
+ /* Put all needed data into mbi_out. */
+ for ( tag = _p(ptr); (u32)tag - mbi_in < mbi_fix->total_size;
+ tag = _p(ALIGN_UP((u32)tag + tag->size, MULTIBOOT2_TAG_ALIGN)) )
+ switch ( tag->type )
+ {
+ case MULTIBOOT2_TAG_TYPE_BOOT_LOADER_NAME:
+ mbi_out->flags |= MBI_LOADERNAME;
+ ptr = get_mb2_string(tag, string, string);
+ mbi_out->boot_loader_name = copy_string(ptr);
+ break;
+
+ case MULTIBOOT2_TAG_TYPE_CMDLINE:
+ mbi_out->flags |= MBI_CMDLINE;
+ ptr = get_mb2_string(tag, string, string);
+ mbi_out->cmdline = copy_string(ptr);
+ break;
+
+ case MULTIBOOT2_TAG_TYPE_BASIC_MEMINFO:
+ mbi_out->flags |= MBI_MEMLIMITS;
+ mbi_out->mem_lower = get_mb2_data(tag, basic_meminfo, mem_lower);
+ mbi_out->mem_upper = get_mb2_data(tag, basic_meminfo, mem_upper);
+ break;
+
+ case MULTIBOOT2_TAG_TYPE_MMAP:
+ if ( get_mb2_data(tag, mmap, entry_size) < sizeof(*mmap_src) )
+ break;
+
+ mbi_out->flags |= MBI_MEMMAP;
+ mbi_out->mmap_length = get_mb2_data(tag, mmap, size);
+ mbi_out->mmap_length -= sizeof(multiboot2_tag_mmap_t);
+ mbi_out->mmap_length /= get_mb2_data(tag, mmap, entry_size);
+ mbi_out->mmap_length *= sizeof(*mmap_dst);
+
+ mbi_out->mmap_addr = alloc_mem(mbi_out->mmap_length);
+
+ mmap_src = get_mb2_data(tag, mmap, entries);
+ mmap_dst = _p(mbi_out->mmap_addr);
+
+ for ( i = 0; i < mbi_out->mmap_length / sizeof(*mmap_dst); i++ )
+ {
+ /* Init size member properly. */
+ mmap_dst[i].size = sizeof(*mmap_dst);
+ mmap_dst[i].size -= sizeof(mmap_dst[i].size);
+ /* Now copy a given region data. */
+ mmap_dst[i].base_addr_low = (u32)mmap_src->addr;
+ mmap_dst[i].base_addr_high = (u32)(mmap_src->addr >> 32);
+ mmap_dst[i].length_low = (u32)mmap_src->len;
+ mmap_dst[i].length_high = (u32)(mmap_src->len >> 32);
+ mmap_dst[i].type = mmap_src->type;
+ mmap_src = _p(mmap_src) + get_mb2_data(tag, mmap, entry_size);
+ }
+ break;
+
+ case MULTIBOOT2_TAG_TYPE_MODULE:
+ if ( mod_idx >= mbi_out->mods_count )
+ break;
+
+ mbi_out_mods[mod_idx].mod_start = get_mb2_data(tag, module, mod_start);
+ mbi_out_mods[mod_idx].mod_end = get_mb2_data(tag, module, mod_end);
+ ptr = get_mb2_string(tag, module, cmdline);
+ mbi_out_mods[mod_idx].string = copy_string(ptr);
+ mbi_out_mods[mod_idx].reserved = 0;
+ ++mod_idx;
+ break;
+
+ case MULTIBOOT2_TAG_TYPE_END:
+ return mbi_out;
+
+ default:
+ break;
+ }
+
+ return mbi_out;
+}
+
+multiboot_info_t __stdcall *reloc(u32 mb_magic, u32 mbi_in, u32 trampoline)
+{
+ alloc = trampoline;
+
+ if ( mb_magic == MULTIBOOT2_BOOTLOADER_MAGIC )
+ return mbi2_reloc(mbi_in);
+ else
+ return mbi_reloc(mbi_in);
+}
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
diff --git a/xen/arch/x86/x86_64/asm-offsets.c b/xen/arch/x86/x86_64/asm-offsets.c
index 0e1f09d..92f5d81 100644
--- a/xen/arch/x86/x86_64/asm-offsets.c
+++ b/xen/arch/x86/x86_64/asm-offsets.c
@@ -13,6 +13,7 @@
#include <asm/fixmap.h>
#include <asm/hardirq.h>
#include <xen/multiboot.h>
+#include <xen/multiboot2.h>
#define DEFINE(_sym, _val) \
asm volatile ("\n.ascii\"==>#define " #_sym " %0 /* " #_val " */<==\"" \
@@ -167,6 +168,14 @@ void __dummy__(void)
OFFSET(MB_flags, multiboot_info_t, flags);
OFFSET(MB_cmdline, multiboot_info_t, cmdline);
OFFSET(MB_mem_lower, multiboot_info_t, mem_lower);
+ BLANK();
+
+ DEFINE(MB2_fixed_sizeof, sizeof(multiboot2_fixed_t));
+ OFFSET(MB2_fixed_total_size, multiboot2_fixed_t, total_size);
+ OFFSET(MB2_tag_type, multiboot2_tag_t, type);
+ OFFSET(MB2_tag_size, multiboot2_tag_t, size);
+ OFFSET(MB2_mem_lower, multiboot2_tag_basic_meminfo_t, mem_lower);
+ BLANK();
OFFSET(DOMAIN_vm_assist, struct domain, vm_assist);
}
diff --git a/xen/include/xen/multiboot2.h b/xen/include/xen/multiboot2.h
new file mode 100644
index 0000000..a3e3119
--- /dev/null
+++ b/xen/include/xen/multiboot2.h
@@ -0,0 +1,169 @@
+/*
+ * Copyright (C) 1999,2003,2007,2008,2009,2010 Free Software Foundation, Inc.
+ *
+ * multiboot2.h - Multiboot 2 header file.
+ *
+ * Based on grub-2.00/include/multiboot2.h file.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL ANY
+ * DEVELOPER OR DISTRIBUTOR BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
+ * IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#ifndef __MULTIBOOT2_H__
+#define __MULTIBOOT2_H__
+
+/* The magic field should contain this. */
+#define MULTIBOOT2_HEADER_MAGIC 0xe85250d6
+
+/* This should be in %eax on x86 architecture. */
+#define MULTIBOOT2_BOOTLOADER_MAGIC 0x36d76289
+
+/* How many bytes from the start of the file we search for the header. */
+#define MULTIBOOT2_SEARCH 32768
+
+/* Multiboot 2 header alignment. */
+#define MULTIBOOT2_HEADER_ALIGN 8
+
+/* Alignment of multiboot 2 modules. */
+#define MULTIBOOT2_MOD_ALIGN 0x00001000
+
+/* Alignment of the multiboot 2 info structure. */
+#define MULTIBOOT2_INFO_ALIGN 0x00000008
+
+/* Multiboot 2 architectures. */
+#define MULTIBOOT2_ARCHITECTURE_I386 0
+#define MULTIBOOT2_ARCHITECTURE_MIPS32 4
+
+/* Header tag types. */
+#define MULTIBOOT2_HEADER_TAG_END 0
+#define MULTIBOOT2_HEADER_TAG_INFORMATION_REQUEST 1
+#define MULTIBOOT2_HEADER_TAG_ADDRESS 2
+#define MULTIBOOT2_HEADER_TAG_ENTRY_ADDRESS 3
+#define MULTIBOOT2_HEADER_TAG_CONSOLE_FLAGS 4
+#define MULTIBOOT2_HEADER_TAG_FRAMEBUFFER 5
+#define MULTIBOOT2_HEADER_TAG_MODULE_ALIGN 6
+#define MULTIBOOT2_HEADER_TAG_EFI_BS 7
+#define MULTIBOOT2_HEADER_TAG_ENTRY_ADDRESS_EFI32 8
+#define MULTIBOOT2_HEADER_TAG_ENTRY_ADDRESS_EFI64 9
+
+/* Header tag flags. */
+#define MULTIBOOT2_HEADER_TAG_REQUIRED 0
+#define MULTIBOOT2_HEADER_TAG_OPTIONAL 1
+
+/* Header console tag console_flags. */
+#define MULTIBOOT2_CONSOLE_FLAGS_CONSOLE_REQUIRED 1
+#define MULTIBOOT2_CONSOLE_FLAGS_EGA_TEXT_SUPPORTED 2
+
+/* Flags set in the 'flags' member of the multiboot header. */
+#define MULTIBOOT2_TAG_TYPE_END 0
+#define MULTIBOOT2_TAG_TYPE_CMDLINE 1
+#define MULTIBOOT2_TAG_TYPE_BOOT_LOADER_NAME 2
+#define MULTIBOOT2_TAG_TYPE_MODULE 3
+#define MULTIBOOT2_TAG_TYPE_BASIC_MEMINFO 4
+#define MULTIBOOT2_TAG_TYPE_BOOTDEV 5
+#define MULTIBOOT2_TAG_TYPE_MMAP 6
+#define MULTIBOOT2_TAG_TYPE_VBE 7
+#define MULTIBOOT2_TAG_TYPE_FRAMEBUFFER 8
+#define MULTIBOOT2_TAG_TYPE_ELF_SECTIONS 9
+#define MULTIBOOT2_TAG_TYPE_APM 10
+#define MULTIBOOT2_TAG_TYPE_EFI32 11
+#define MULTIBOOT2_TAG_TYPE_EFI64 12
+#define MULTIBOOT2_TAG_TYPE_SMBIOS 13
+#define MULTIBOOT2_TAG_TYPE_ACPI_OLD 14
+#define MULTIBOOT2_TAG_TYPE_ACPI_NEW 15
+#define MULTIBOOT2_TAG_TYPE_NETWORK 16
+#define MULTIBOOT2_TAG_TYPE_EFI_MMAP 17
+#define MULTIBOOT2_TAG_TYPE_EFI_BS 18
+#define MULTIBOOT2_TAG_TYPE_EFI32_IH 19
+#define MULTIBOOT2_TAG_TYPE_EFI64_IH 20
+
+/* Multiboot 2 tag alignment. */
+#define MULTIBOOT2_TAG_ALIGN 8
+
+/* Memory types. */
+#define MULTIBOOT2_MEMORY_AVAILABLE 1
+#define MULTIBOOT2_MEMORY_RESERVED 2
+#define MULTIBOOT2_MEMORY_ACPI_RECLAIMABLE 3
+#define MULTIBOOT2_MEMORY_NVS 4
+#define MULTIBOOT2_MEMORY_BADRAM 5
+
+/* Framebuffer types. */
+#define MULTIBOOT2_FRAMEBUFFER_TYPE_INDEXED 0
+#define MULTIBOOT2_FRAMEBUFFER_TYPE_RGB 1
+#define MULTIBOOT2_FRAMEBUFFER_TYPE_EGA_TEXT 2
+
+#ifndef __ASSEMBLY__
+typedef struct {
+ u32 total_size;
+ u32 reserved;
+} multiboot2_fixed_t;
+
+typedef struct {
+ u32 type;
+ u32 size;
+} multiboot2_tag_t;
+
+typedef struct {
+ u32 type;
+ u32 size;
+ char string[];
+} multiboot2_tag_string_t;
+
+typedef struct {
+ u32 type;
+ u32 size;
+ u32 mem_lower;
+ u32 mem_upper;
+} multiboot2_tag_basic_meminfo_t;
+
+typedef struct {
+ u64 addr;
+ u64 len;
+ u32 type;
+ u32 zero;
+} multiboot2_memory_map_t;
+
+typedef struct {
+ u32 type;
+ u32 size;
+ u32 entry_size;
+ u32 entry_version;
+ multiboot2_memory_map_t entries[];
+} multiboot2_tag_mmap_t;
+
+typedef struct {
+ u32 type;
+ u32 size;
+ u64 pointer;
+} multiboot2_tag_efi64_t;
+
+typedef struct {
+ u32 type;
+ u32 size;
+ u64 pointer;
+} multiboot2_tag_efi64_ih_t;
+
+typedef struct {
+ u32 type;
+ u32 size;
+ u32 mod_start;
+ u32 mod_end;
+ char cmdline[];
+} multiboot2_tag_module_t;
+#endif /* __ASSEMBLY__ */
+
+#endif /* __MULTIBOOT2_H__ */
--
1.7.10.4
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply related [flat|nested] 15+ messages in thread* [PATCH v13 2/9] efi: build xen.gz with EFI code
2017-01-25 22:11 [PATCH v13 0/9] x86: multiboot2 protocol support Daniel Kiper
2017-01-25 22:11 ` [PATCH v13 1/9] x86: add " Daniel Kiper
@ 2017-01-25 22:11 ` Daniel Kiper
2017-01-25 22:11 ` [PATCH v13 3/9] efi: create new early memory allocator Daniel Kiper
` (6 subsequent siblings)
8 siblings, 0 replies; 15+ messages in thread
From: Daniel Kiper @ 2017-01-25 22:11 UTC (permalink / raw)
To: xen-devel
Cc: jgross, sstabellini, andrew.cooper3, cardoe, pgnet.dev, ning.sun,
julien.grall, jbeulich, qiaowei.ren, gang.wei, fu.wei
Build xen.gz with EFI code. We need this to support multiboot2
protocol on EFI platforms.
If we wish to load non-ELF file using multiboot (v1) or multiboot2 then
it must contain "linear" (or "flat") representation of code and data.
This is requirement of both boot protocols. Currently, PE file contains
many sections which are not "linear" (one after another without any holes)
or even do not have representation in a file (e.g. BSS). From EFI point
of view everything is OK and works. However, this file layout cannot be
properly interpreted by multiboot protocols family. In theory there is
a chance that we could build proper PE file (from multiboot protocols POV)
using current build system. However, it means that xen.efi further diverge
from Xen ELF file (in terms of contents and build method). On the other
hand ELF has all needed properties. So, it means that this is good starting
point for further development. Additionally, I think that this is also good
starting point for further xen.efi code and build optimizations. It looks
that there is a chance that finally we can generate xen.efi directly from
Xen ELF using just simple objcopy or other tool. This way we will have one
Xen binary which can be loaded by three boot protocols: EFI native loader,
multiboot (v1) and multiboot2.
Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Doug Goldstein <cardoe@cardoe.com>
Tested-by: Doug Goldstein <cardoe@cardoe.com>
---
v6 - suggestions/fixes:
- improve efi_enabled() checks in efi_runtime_call()
(suggested by Jan Beulich).
v5 - suggestions/fixes:
- properly calculate efi symbol address in
xen/arch/x86/xen.lds.S (I hope that this
change does not invalidate Jan's ACK).
v4 - suggestions/fixes:
- functions should return -ENOSYS instead
of -EOPNOTSUPP if EFI runtime services
are not available
(suggested by Jan Beulich),
- remove stale bits from xen/arch/x86/Makefile
(suggested by Jan Beulich).
v3 - suggestions/fixes:
- check for EFI platform in EFI code
(suggested by Jan Beulich),
- fix Makefiles
(suggested by Jan Beulich),
- improve commit message
(suggested by Jan Beulich).
v2 - suggestions/fixes:
- build EFI code only if it is supported in a given build environment
(suggested by Jan Beulich).
---
xen/arch/x86/Makefile | 2 +-
xen/arch/x86/efi/Makefile | 12 ++++--------
xen/arch/x86/xen.lds.S | 4 ++--
xen/common/efi/boot.c | 3 +++
xen/common/efi/runtime.c | 9 +++++++++
5 files changed, 19 insertions(+), 11 deletions(-)
diff --git a/xen/arch/x86/Makefile b/xen/arch/x86/Makefile
index 007dced..08e9f7b 100644
--- a/xen/arch/x86/Makefile
+++ b/xen/arch/x86/Makefile
@@ -219,6 +219,6 @@ efi/mkreloc: efi/mkreloc.c
clean::
rm -f asm-offsets.s *.lds boot/*.o boot/*~ boot/core boot/mkelf32
rm -f $(BASEDIR)/.xen-syms.[0-9]* boot/.*.d
- rm -f $(BASEDIR)/.xen.efi.[0-9]* efi/*.o efi/.*.d efi/*.efi efi/disabled efi/mkreloc
+ rm -f $(BASEDIR)/.xen.efi.[0-9]* efi/*.efi efi/disabled efi/mkreloc
rm -f boot/cmdline.S boot/reloc.S boot/*.lnk boot/*.bin
rm -f note.o
diff --git a/xen/arch/x86/efi/Makefile b/xen/arch/x86/efi/Makefile
index ad3fdf7..442f3fc 100644
--- a/xen/arch/x86/efi/Makefile
+++ b/xen/arch/x86/efi/Makefile
@@ -1,18 +1,14 @@
CFLAGS += -fshort-wchar
-obj-y += stub.o
-
-create = test -e $(1) || touch -t 199901010000 $(1)
-
efi := y$(shell rm -f disabled)
efi := $(if $(efi),$(shell $(CC) $(filter-out $(CFLAGS-y) .%.d,$(CFLAGS)) -c check.c 2>disabled && echo y))
efi := $(if $(efi),$(shell $(LD) -mi386pep --subsystem=10 -o check.efi check.o 2>disabled && echo y))
-efi := $(if $(efi),$(shell rm disabled)y,$(shell $(call create,boot.init.o); $(call create,runtime.o)))
-
-extra-$(efi) += boot.init.o relocs-dummy.o runtime.o compat.o buildid.o
+efi := $(if $(efi),$(shell rm disabled)y)
%.o: %.ihex
$(OBJCOPY) -I ihex -O binary $< $@
-stub.o: $(extra-y)
+obj-y := stub.o
+obj-$(efi) := boot.init.o compat.o relocs-dummy.o runtime.o
+extra-$(efi) += buildid.o
nogcov-$(efi) += stub.o
diff --git a/xen/arch/x86/xen.lds.S b/xen/arch/x86/xen.lds.S
index 7676de9..b0b1c9b 100644
--- a/xen/arch/x86/xen.lds.S
+++ b/xen/arch/x86/xen.lds.S
@@ -270,10 +270,10 @@ SECTIONS
.pad : {
. = ALIGN(MB(16));
} :text
-#else
- efi = .;
#endif
+ efi = DEFINED(efi) ? efi : .;
+
/* Sections to be discarded */
/DISCARD/ : {
*(.exit.text)
diff --git a/xen/common/efi/boot.c b/xen/common/efi/boot.c
index 3e5e4ab..df8c702 100644
--- a/xen/common/efi/boot.c
+++ b/xen/common/efi/boot.c
@@ -1251,6 +1251,9 @@ void __init efi_init_memory(void)
} *extra, *extra_head = NULL;
#endif
+ if ( !efi_enabled(EFI_BOOT) )
+ return;
+
printk(XENLOG_INFO "EFI memory map:%s\n",
map_bs ? " (mapping BootServices)" : "");
for ( i = 0; i < efi_memmap_size; i += efi_mdesc_size )
diff --git a/xen/common/efi/runtime.c b/xen/common/efi/runtime.c
index 8c44835..25323de 100644
--- a/xen/common/efi/runtime.c
+++ b/xen/common/efi/runtime.c
@@ -196,6 +196,9 @@ int efi_get_info(uint32_t idx, union xenpf_efi_info *info)
{
unsigned int i, n;
+ if ( !efi_enabled(EFI_BOOT) )
+ return -ENOSYS;
+
switch ( idx )
{
case XEN_FW_EFI_VERSION:
@@ -331,6 +334,12 @@ int efi_runtime_call(struct xenpf_efi_runtime_call *op)
EFI_STATUS status = EFI_NOT_STARTED;
int rc = 0;
+ if ( !efi_enabled(EFI_BOOT) )
+ return -ENOSYS;
+
+ if ( !efi_enabled(EFI_RS) )
+ return -EOPNOTSUPP;
+
switch ( op->function )
{
case XEN_EFI_get_time:
--
1.7.10.4
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply related [flat|nested] 15+ messages in thread* [PATCH v13 3/9] efi: create new early memory allocator
2017-01-25 22:11 [PATCH v13 0/9] x86: multiboot2 protocol support Daniel Kiper
2017-01-25 22:11 ` [PATCH v13 1/9] x86: add " Daniel Kiper
2017-01-25 22:11 ` [PATCH v13 2/9] efi: build xen.gz with EFI code Daniel Kiper
@ 2017-01-25 22:11 ` Daniel Kiper
2017-01-25 22:11 ` [PATCH v13 4/9] x86: add multiboot2 protocol support for EFI platforms Daniel Kiper
` (5 subsequent siblings)
8 siblings, 0 replies; 15+ messages in thread
From: Daniel Kiper @ 2017-01-25 22:11 UTC (permalink / raw)
To: xen-devel
Cc: jgross, sstabellini, andrew.cooper3, cardoe, pgnet.dev, ning.sun,
julien.grall, jbeulich, qiaowei.ren, gang.wei, fu.wei
There is a problem with place_string() which is used as early memory
allocator. It gets memory chunks starting from start symbol and goes
down. Sadly this does not work when Xen is loaded using multiboot2
protocol because then the start lives on 1 MiB address and we should
not allocate a memory from below of it. So, I tried to use mem_lower
address calculated by GRUB2. However, this solution works only on some
machines. There are machines in the wild (e.g. Dell PowerEdge R820)
which uses first ~640 KiB for boot services code or data... :-(((
Hence, we need new memory allocator for Xen EFI boot code which is
quite simple and generic and could be used by place_string() and
efi_arch_allocate_mmap_buffer(). I think about following solutions:
1) We could use native EFI allocation functions (e.g. AllocatePool()
or AllocatePages()) to get memory chunk. However, later (somewhere
in __start_xen()) we must copy its contents to safe place or reserve
it in e820 memory map and map it in Xen virtual address space. This
means that the code referring to Xen command line, loaded modules and
EFI memory map, mostly in __start_xen(), will be further complicated
and diverge from legacy BIOS cases. Additionally, both former things
have to be placed below 4 GiB because their addresses are stored in
multiboot_info_t structure which has 32-bit relevant members.
2) We may allocate memory area statically somewhere in Xen code which
could be used as memory pool for early dynamic allocations. Looks
quite simple. Additionally, it would not depend on EFI at all and
could be used on legacy BIOS platforms if we need it. However, we
must carefully choose size of this pool. We do not want increase Xen
binary size too much and waste too much memory but also we must fit
at least memory map on x86 EFI platforms. As I saw on small machine,
e.g. IBM System x3550 M2 with 8 GiB RAM, memory map may contain more
than 200 entries. Every entry on x86-64 platform is 40 bytes in size.
So, it means that we need more than 8 KiB for EFI memory map only.
Additionally, if we use this memory pool for Xen and modules command
line storage (it would be used when xen.efi is executed as EFI application)
then we should add, I think, about 1 KiB. In this case, to be on safe
side, we should assume at least 64 KiB pool for early memory allocations.
Which is about 4 times of our earlier calculations. However, during
discussion on Xen-devel Jan Beulich suggested that just in case we should
use 1 MiB memory pool like it is in original place_string() implementation.
So, let's use 1 MiB as it was proposed. If we think that we should not
waste unallocated memory in the pool on running system then we can mark
this region as __initdata and move all required data to dynamically
allocated places somewhere in __start_xen().
2a) We could put memory pool into .bss.page_aligned section. Then allocate
memory chunks starting from the lowest address. After init phase we can
free unused portion of the memory pool as in case of .init.text or .init.data
sections. This way we do not need to allocate any space in image file and
freeing of unused area in the memory pool is very simple.
Now #2a solution is implemented because it is quite simple and requires
limited number of changes, especially in __start_xen().
New allocator is quite generic and can be used on ARM platforms too.
Though it is not enabled on ARM yet due to lack of some prereq.
List of them is placed before ebmalloc code.
Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Doug Goldstein <cardoe@cardoe.com>
Tested-by: Doug Goldstein <cardoe@cardoe.com>
---
v11 - suggestions/fixes:
- #ifdef only EBMALLOC_SIZE from ebmalloc machinery
(suggested by Jan Beulich).
v10 - suggestions/fixes:
- remove unneeded ARM free_ebmalloc_unused_mem() stub.
v9 - suggestions/fixes:
- call free_ebmalloc_unused_mem() from efi_init_memory()
instead of xen/arch/arm/setup.c:init_done()
(suggested by Jan Beulich),
- improve comments.
v8 - suggestions/fixes:
- disable whole ebmalloc machinery on ARM platforms,
- add comment saying what should be done before
enabling ebmalloc on ARM,
(suggested by Julien Grall),
- move ebmalloc code before efi-boot.h inclusion and
remove unneeded forward declaration
(suggested by Jan Beulich),
- remove free_ebmalloc_unused_mem() call from
xen/arch/arm/setup.c:init_done()
(suggested by Julien Grall),
- improve commit message.
v7 - suggestions/fixes:
- enable most of ebmalloc machinery on ARM platforms
(suggested by Jan Beulich),
- remove unneeded cast
(suggested by Jan Beulich),
- wrap long line
(suggested by Jan Beulich),
- improve commit message.
v6 - suggestions/fixes:
- optimize ebmalloc allocator,
- move ebmalloc machinery to xen/common/efi/boot.c
(suggested by Jan Beulich),
- enforce PAGE_SIZE ebmalloc_mem alignment
(suggested by Jan Beulich),
- ebmalloc() must allocate properly
aligned memory regions
(suggested by Jan Beulich),
- printk() should use XENLOG_INFO
(suggested by Jan Beulich).
v4 - suggestions/fixes:
- move from #2 solution to #2a solution,
- improve commit message.
---
xen/arch/x86/efi/efi-boot.h | 11 +++-------
xen/arch/x86/setup.c | 3 +--
xen/common/efi/boot.c | 50 +++++++++++++++++++++++++++++++++++++++++++
3 files changed, 54 insertions(+), 10 deletions(-)
diff --git a/xen/arch/x86/efi/efi-boot.h b/xen/arch/x86/efi/efi-boot.h
index 388c4ea..62c010e 100644
--- a/xen/arch/x86/efi/efi-boot.h
+++ b/xen/arch/x86/efi/efi-boot.h
@@ -114,7 +114,7 @@ static void __init relocate_trampoline(unsigned long phys)
static void __init place_string(u32 *addr, const char *s)
{
- static char *__initdata alloc = start;
+ char *alloc = NULL;
if ( s && *s )
{
@@ -122,7 +122,7 @@ static void __init place_string(u32 *addr, const char *s)
const char *old = (char *)(long)*addr;
size_t len2 = *addr ? strlen(old) + 1 : 0;
- alloc -= len1 + len2;
+ alloc = ebmalloc(len1 + len2);
/*
* Insert new string before already existing one. This is needed
* for options passed on the command line to override options from
@@ -205,12 +205,7 @@ static void __init efi_arch_process_memory_map(EFI_SYSTEM_TABLE *SystemTable,
static void *__init efi_arch_allocate_mmap_buffer(UINTN map_size)
{
- place_string(&mbi.mem_upper, NULL);
- mbi.mem_upper -= map_size;
- mbi.mem_upper &= -__alignof__(EFI_MEMORY_DESCRIPTOR);
- if ( mbi.mem_upper < xen_phys_start )
- return NULL;
- return (void *)(long)mbi.mem_upper;
+ return ebmalloc(map_size);
}
static void __init efi_arch_pre_exit_boot(void)
diff --git a/xen/arch/x86/setup.c b/xen/arch/x86/setup.c
index 0ccef1d..d4b7d25 100644
--- a/xen/arch/x86/setup.c
+++ b/xen/arch/x86/setup.c
@@ -1124,8 +1124,7 @@ void __init noreturn __start_xen(unsigned long mbi_p)
if ( !xen_phys_start )
panic("Not enough memory to relocate Xen.");
- reserve_e820_ram(&boot_e820, efi_enabled(EFI_LOADER) ? mbi->mem_upper : __pa(&_start),
- __pa(&_end));
+ reserve_e820_ram(&boot_e820, __pa(&_start), __pa(&_end));
/* Late kexec reservation (dynamic start address). */
kexec_reserve_area(&boot_e820);
diff --git a/xen/common/efi/boot.c b/xen/common/efi/boot.c
index df8c702..36dbb71 100644
--- a/xen/common/efi/boot.c
+++ b/xen/common/efi/boot.c
@@ -98,6 +98,54 @@ static CHAR16 __initdata newline[] = L"\r\n";
#define PrintStr(s) StdOut->OutputString(StdOut, s)
#define PrintErr(s) StdErr->OutputString(StdErr, s)
+#ifdef CONFIG_ARM
+/*
+ * TODO: Enable EFI boot allocator on ARM.
+ * This code can be common for x86 and ARM.
+ * Things TODO on ARM before enabling ebmalloc:
+ * - estimate required EBMALLOC_SIZE value,
+ * - where (in which section) ebmalloc_mem[] should live; if in
+ * .bss.page_aligned, as it is right now, then whole BSS zeroing
+ * have to be disabled in xen/arch/arm/arm64/head.S; though BSS
+ * should be initialized somehow before use of variables living there,
+ * - use ebmalloc() in ARM/common EFI boot code,
+ * - call free_ebmalloc_unused_mem() somewhere in init code.
+ */
+#define EBMALLOC_SIZE MB(0)
+#else
+#define EBMALLOC_SIZE MB(1)
+#endif
+
+static char __section(".bss.page_aligned") __aligned(PAGE_SIZE)
+ ebmalloc_mem[EBMALLOC_SIZE];
+static unsigned long __initdata ebmalloc_allocated;
+
+/* EFI boot allocator. */
+static void __init __maybe_unused *ebmalloc(size_t size)
+{
+ void *ptr = ebmalloc_mem + ebmalloc_allocated;
+
+ ebmalloc_allocated += (size + sizeof(void *) - 1) & ~(sizeof(void *) - 1);
+
+ if ( ebmalloc_allocated > sizeof(ebmalloc_mem) )
+ blexit(L"Out of static memory\r\n");
+
+ return ptr;
+}
+
+static void __init __maybe_unused free_ebmalloc_unused_mem(void)
+{
+ unsigned long start, end;
+
+ start = (unsigned long)ebmalloc_mem + PAGE_ALIGN(ebmalloc_allocated);
+ end = (unsigned long)ebmalloc_mem + sizeof(ebmalloc_mem);
+
+ destroy_xen_mappings(start, end);
+ init_xenheap_pages(__pa(start), __pa(end));
+
+ printk(XENLOG_INFO "Freed %lukB unused BSS memory\n", (end - start) >> 10);
+}
+
/*
* Include architecture specific implementation here, which references the
* static globals defined above.
@@ -1251,6 +1299,8 @@ void __init efi_init_memory(void)
} *extra, *extra_head = NULL;
#endif
+ free_ebmalloc_unused_mem();
+
if ( !efi_enabled(EFI_BOOT) )
return;
--
1.7.10.4
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply related [flat|nested] 15+ messages in thread* [PATCH v13 4/9] x86: add multiboot2 protocol support for EFI platforms
2017-01-25 22:11 [PATCH v13 0/9] x86: multiboot2 protocol support Daniel Kiper
` (2 preceding siblings ...)
2017-01-25 22:11 ` [PATCH v13 3/9] efi: create new early memory allocator Daniel Kiper
@ 2017-01-25 22:11 ` Daniel Kiper
2017-01-25 22:20 ` Doug Goldstein
2017-01-25 22:11 ` [PATCH v13 5/9] x86: change default load address from 1 MiB to 2 MiB Daniel Kiper
` (4 subsequent siblings)
8 siblings, 1 reply; 15+ messages in thread
From: Daniel Kiper @ 2017-01-25 22:11 UTC (permalink / raw)
To: xen-devel
Cc: jgross, sstabellini, andrew.cooper3, cardoe, pgnet.dev, ning.sun,
julien.grall, jbeulich, qiaowei.ren, gang.wei, fu.wei
This way Xen can be loaded on EFI platforms using GRUB2 and
other boot loaders which support multiboot2 protocol.
Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
---
v13 - suggestions/fixes:
- move vga_text_buffer and efi_platform to .init.data section
(suggested by Jan Beulich),
- reduce number of error branches in EFI code in xen/arch/x86/boot/head.S
(suggested by Jan Beulich),
- rename run_bs label to .Lrun_bs
(suggested by Jan Beulich),
- align the stack as UEFI spec requires
(suggested by Jan Beulich),
- change trampoline region memory layout
(suggested by Jan Beulich),
- revert changes in efi_arch_pre_exit_boot()
(suggested by Jan Beulich),
- relocate_trampoline() must set trampoline_phys for all bootloaders;
otherwise fallback allocator is always used if Xen was loaded with
Multiboot2 protocol,
- change err type in efi_multiboot2() to "static const CHAR16 __initconst"
(suggested by Jan Beulich),
- change asm "g" constraint to "rm" in efi_multiboot2()
(suggested by Jan Beulich),
- improve comments
(suggested by Jan Beulich and Doug Goldstein).
v12 - suggestions/fixes:
- rename __efi64_start to __efi64_mb2_start
(suggested by Andrew Cooper),
- use efi_arch_memory_setup() machinery as trampoline
et consortes main memory allocator
(suggested by Doug Goldstein),
- allocate space for mbi struct in efi_arch_memory_setup() too;
this thing was not taken into account in earlier releases,
- revert trampoline et consortes fallback memory allocator code
in efi_arch_process_memory_map() to current upstream state
(suggested by Doug Goldstein),
- further simplify efi_arch_pre_exit_boot() code,
- call efi_arch_memory_setup() from efi_multiboot2()
(suggested by Doug Goldstein),
- fix asembly call argument in xen/arch/x86/efi/stub.c
(suggested by Andrew Cooper),
- add ASSERT() for trampoline size
(suggested by Doug Goldstein),
- add KB() macro
(suggested by Doug Goldstein),
- improve comments
(suggested by Andrew Cooper and Doug Goldstein).
v10 - suggestions/fixes:
- replace ljmpl with lretq
(suggested by Andrew Cooper),
- introduce efi_platform to increase code readability
(suggested by Andrew Cooper).
v9 - suggestions/fixes:
- use .L labels instead of numeric ones in multiboot2 data scanning loops
(suggested by Jan Beulich).
v8 - suggestions/fixes:
- use __bss_start(%rip)/__bss_end(%rip) instead of
of .startof.(.bss)(%rip)/$.sizeof.(.bss) because
latter is not tested extensively in different
built environments yet
(suggested by Andrew Cooper),
- fix multiboot2 data scanning loop in x86_32 code
(suggested by Jan Beulich),
- add check for extra mem for mbi data if Xen is loaded
via multiboot2 protocol on EFI platform
(suggested by Jan Beulich),
- improve comments
(suggested by Jan Beulich).
v7 - suggestions/fixes:
- do not allocate twice memory for trampoline if we were
loaded via multiboot2 protocol on EFI platform,
- wrap long line
(suggested by Jan Beulich),
- improve comments
(suggested by Jan Beulich).
v6 - suggestions/fixes:
- improve label names in assembly
error printing code
(suggested by Jan Beulich),
- improve comments
(suggested by Jan Beulich),
- various minor cleanups and fixes
(suggested by Jan Beulich).
v4 - suggestions/fixes:
- remove redundant BSS alignment,
- update BSS alignment check,
- use __set_bit() instead of set_bit() if possible
(suggested by Jan Beulich),
- call efi_arch_cpu() from efi_multiboot2()
even if the same work is done later in
other place right now
(suggested by Jan Beulich),
- xen/arch/x86/efi/stub.c:efi_multiboot2()
fail properly on EFI platforms,
- do not read data beyond the end of multiboot2
information in xen/arch/x86/boot/head.S
(suggested by Jan Beulich),
- use 32-bit registers in x86_64 code if possible
(suggested by Jan Beulich),
- multiboot2 information address is 64-bit
in x86_64 code, so, treat it is as is
(suggested by Jan Beulich),
- use cmovcc if possible,
- leave only one space between rep and stosq
(suggested by Jan Beulich),
- improve error handling,
- improve early error messages,
(suggested by Jan Beulich),
- improve early error messages printing code,
- improve label names
(suggested by Jan Beulich),
- improve comments
(suggested by Jan Beulich),
- various minor cleanups.
v3 - suggestions/fixes:
- take into account alignment when skipping multiboot2 fixed part
(suggested by Konrad Rzeszutek Wilk),
- improve segment registers initialization
(suggested by Jan Beulich),
- improve comments
(suggested by Jan Beulich and Konrad Rzeszutek Wilk),
- improve commit message
(suggested by Jan Beulich).
v2 - suggestions/fixes:
- generate multiboot2 header using macros
(suggested by Jan Beulich),
- switch CPU to x86_32 mode before
jumping to 32-bit code
(suggested by Andrew Cooper),
- reduce code changes to increase patch readability
(suggested by Jan Beulich),
- improve comments
(suggested by Jan Beulich),
- ignore MULTIBOOT2_TAG_TYPE_BASIC_MEMINFO tag on EFI platform
and find on my own multiboot2.mem_lower value,
- stop execution if EFI platform is detected
in legacy BIOS path.
---
xen/arch/x86/boot/head.S | 297 ++++++++++++++++++++++++++++++++++---
xen/arch/x86/boot/reloc.c | 2 +-
xen/arch/x86/efi/efi-boot.h | 52 ++++++-
xen/arch/x86/efi/stub.c | 39 +++++
xen/arch/x86/x86_64/asm-offsets.c | 2 +
xen/arch/x86/xen.lds.S | 7 +-
xen/common/efi/boot.c | 11 ++
xen/include/asm-x86/config.h | 3 +
xen/include/xen/config.h | 1 +
9 files changed, 391 insertions(+), 23 deletions(-)
diff --git a/xen/arch/x86/boot/head.S b/xen/arch/x86/boot/head.S
index 84cf44d..2ecdcb3 100644
--- a/xen/arch/x86/boot/head.S
+++ b/xen/arch/x86/boot/head.S
@@ -89,6 +89,13 @@ multiboot2_header_start:
0, /* Number of the lines - no preference. */ \
0 /* Number of bits per pixel - no preference. */
+ /* Request that ExitBootServices() not be called. */
+ mb2ht_init MB2_HT(EFI_BS), MB2_HT(OPTIONAL)
+
+ /* EFI64 Multiboot2 entry point. */
+ mb2ht_init MB2_HT(ENTRY_ADDRESS_EFI64), MB2_HT(OPTIONAL), \
+ sym_phys(__efi64_mb2_start)
+
/* Multiboot2 header end tag. */
mb2ht_init MB2_HT(END), MB2_HT(REQUIRED)
.Lmultiboot2_header_end:
@@ -100,20 +107,50 @@ multiboot2_header_start:
gdt_boot_descr:
.word 6*8-1
.long sym_phys(trampoline_gdt)
+ .long 0 /* Needed for 64-bit lgdt */
.Lbad_cpu_msg: .asciz "ERR: Not a 64-bit CPU!"
.Lbad_ldr_msg: .asciz "ERR: Not a Multiboot bootloader!"
+.Lbad_ldr_nbs: .asciz "ERR: Bootloader shutdown EFI x64 boot services!"
+.Lbad_ldr_nst: .asciz "ERR: EFI SystemTable is not provided by bootloader!"
+.Lbad_ldr_nih: .asciz "ERR: EFI ImageHandle is not provided by bootloader!"
+.Lbad_efi_msg: .asciz "ERR: EFI IA-32 platforms are not supported!"
+
+ .section .init.data, "a", @progbits
+ .align 4
+
+vga_text_buffer:
+ .long 0xb8000
+
+efi_platform:
+ .byte 0
.section .init.text, "ax", @progbits
bad_cpu:
mov $(sym_phys(.Lbad_cpu_msg)),%esi # Error message
- jmp print_err
+ jmp .Lget_vtb
not_multiboot:
mov $(sym_phys(.Lbad_ldr_msg)),%esi # Error message
-print_err:
- mov $0xB8000,%edi # VGA framebuffer
-1: mov (%esi),%bl
+ jmp .Lget_vtb
+.Lmb2_no_st:
+ mov $(sym_phys(.Lbad_ldr_nst)),%esi # Error message
+ jmp .Lget_vtb
+.Lmb2_no_ih:
+ mov $(sym_phys(.Lbad_ldr_nih)),%esi # Error message
+ jmp .Lget_vtb
+.Lmb2_no_bs:
+ mov $(sym_phys(.Lbad_ldr_nbs)),%esi # Error message
+ xor %edi,%edi # No VGA text buffer
+ jmp .Lsend_chr
+.Lmb2_efi_ia_32:
+ mov $(sym_phys(.Lbad_efi_msg)),%esi # Error message
+ xor %edi,%edi # No VGA text buffer
+ jmp .Lsend_chr
+.Lget_vtb:
+ mov sym_phys(vga_text_buffer),%edi
+.Lsend_chr:
+ mov (%esi),%bl
test %bl,%bl # Terminate on '\0' sentinel
je .Lhalt
mov $0x3f8+5,%dx # UART Line Status Register
@@ -123,13 +160,193 @@ print_err:
mov $0x3f8+0,%dx # UART Transmit Holding Register
mov %bl,%al
out %al,%dx # Send a character over the serial line
- movsb # Write a character to the VGA framebuffer
+ test %edi,%edi # Is the VGA text buffer available?
+ jz .Lsend_chr
+ movsb # Write a character to the VGA text buffer
mov $7,%al
- stosb # Write an attribute to the VGA framebuffer
- jmp 1b
+ stosb # Write an attribute to the VGA text buffer
+ jmp .Lsend_chr
.Lhalt: hlt
jmp .Lhalt
+ .code64
+
+__efi64_mb2_start:
+ /*
+ * Multiboot2 spec says that here CPU is in 64-bit mode. However, there
+ * is also guarantee that all code and data is always put by the bootloader
+ * below 4 GiB. Hence, we can safely use in most cases 32-bit addressing.
+ */
+
+ cld
+
+ /* VGA is not available on EFI platforms. */
+ movl $0,vga_text_buffer(%rip)
+
+ /* Check for Multiboot2 bootloader. */
+ cmp $MULTIBOOT2_BOOTLOADER_MAGIC,%eax
+ je .Lefi_multiboot2_proto
+
+ /* Jump to not_multiboot after switching CPU to x86_32 mode. */
+ lea not_multiboot(%rip),%r15d
+ jmp x86_32_switch
+
+.Lefi_multiboot2_proto:
+ /* Zero EFI SystemTable and EFI ImageHandle addresses. */
+ xor %esi,%esi
+ xor %edi,%edi
+
+ /* Skip Multiboot2 information fixed part. */
+ lea (MB2_fixed_sizeof+MULTIBOOT2_TAG_ALIGN-1)(%rbx),%ecx
+ and $~(MULTIBOOT2_TAG_ALIGN-1),%ecx
+
+.Lefi_mb2_tsize:
+ /* Check Multiboot2 information total size. */
+ mov %ecx,%r8d
+ sub %ebx,%r8d
+ cmp %r8d,MB2_fixed_total_size(%rbx)
+ jbe .Lrun_bs
+
+ /* Are EFI boot services available? */
+ cmpl $MULTIBOOT2_TAG_TYPE_EFI_BS,MB2_tag_type(%rcx)
+ jne .Lefi_mb2_st
+
+ /* We are on EFI platform and EFI boot services are available. */
+ incb efi_platform(%rip)
+
+ /*
+ * Disable real mode and other legacy stuff which should not
+ * be run on EFI platforms.
+ */
+ incb skip_realmode(%rip)
+ jmp .Lefi_mb2_next_tag
+
+.Lefi_mb2_st:
+ /* Get EFI SystemTable address from Multiboot2 information. */
+ cmpl $MULTIBOOT2_TAG_TYPE_EFI64,MB2_tag_type(%rcx)
+ cmove MB2_efi64_st(%rcx),%rsi
+ je .Lefi_mb2_next_tag
+
+ /* Get EFI ImageHandle address from Multiboot2 information. */
+ cmpl $MULTIBOOT2_TAG_TYPE_EFI64_IH,MB2_tag_type(%rcx)
+ cmove MB2_efi64_ih(%rcx),%rdi
+ je .Lefi_mb2_next_tag
+
+ /* Is it the end of Multiboot2 information? */
+ cmpl $MULTIBOOT2_TAG_TYPE_END,MB2_tag_type(%rcx)
+ je .Lrun_bs
+
+.Lefi_mb2_next_tag:
+ /* Go to next Multiboot2 information tag. */
+ add MB2_tag_size(%rcx),%ecx
+ add $(MULTIBOOT2_TAG_ALIGN-1),%ecx
+ and $~(MULTIBOOT2_TAG_ALIGN-1),%ecx
+ jmp .Lefi_mb2_tsize
+
+.Lrun_bs:
+ /* Are EFI boot services available? */
+ cmpb $0,efi_platform(%rip)
+
+ /* Jump to .Lmb2_no_bs after switching CPU to x86_32 mode. */
+ lea .Lmb2_no_bs(%rip),%r15d
+ jz x86_32_switch
+
+ /* Is EFI SystemTable address provided by boot loader? */
+ test %rsi,%rsi
+
+ /* Jump to .Lmb2_no_st after switching CPU to x86_32 mode. */
+ lea .Lmb2_no_st(%rip),%r15d
+ jz x86_32_switch
+
+ /* Is EFI ImageHandle address provided by boot loader? */
+ test %rdi,%rdi
+
+ /* Jump to .Lmb2_no_ih after switching CPU to x86_32 mode. */
+ lea .Lmb2_no_ih(%rip),%r15d
+ jz x86_32_switch
+
+ /* Align the stack as UEFI spec requires. */
+ add $15,%rsp
+ and $~15,%rsp
+
+ push %rax
+ push %rdi
+
+ /*
+ * Initialize BSS (no nasty surprises!).
+ * It must be done earlier than in BIOS case
+ * because efi_multiboot2() touches it.
+ */
+ lea __bss_start(%rip),%edi
+ lea __bss_end(%rip),%ecx
+ sub %edi,%ecx
+ shr $3,%ecx
+ xor %eax,%eax
+ rep stosq
+
+ pop %rdi
+
+ /* Align the stack as UEFI spec requires. */
+ push %rdi
+
+ /*
+ * efi_multiboot2() is called according to System V AMD64 ABI:
+ * - IN: %rdi - EFI ImageHandle, %rsi - EFI SystemTable,
+ * - OUT: %rax - trampoline address.
+ *
+ * MULTIBOOT2_TAG_TYPE_BASIC_MEMINFO tag is not provided
+ * on EFI platforms. Hence, it could not be used like
+ * on legacy BIOS platforms.
+ */
+ call efi_multiboot2
+
+ /* Convert memory address to bytes/16 and store it in safe place. */
+ shr $4,%eax
+ mov %eax,%ecx
+
+ pop %rdi
+ pop %rax
+
+ /* Jump to trampoline_setup after switching CPU to x86_32 mode. */
+ lea trampoline_setup(%rip),%r15d
+
+x86_32_switch:
+ mov %r15d,%edi
+
+ cli
+
+ /* Initialize GDTR. */
+ lgdt gdt_boot_descr(%rip)
+
+ /* Reload code selector. */
+ pushq $BOOT_CS32
+ lea cs32_switch(%rip),%edx
+ push %rdx
+ lretq
+
+ .code32
+
+cs32_switch:
+ /* Initialize basic data segments. */
+ mov $BOOT_DS,%edx
+ mov %edx,%ds
+ mov %edx,%es
+ mov %edx,%ss
+ /* %esp is initialized later. */
+
+ /* Load null descriptor to unused segment registers. */
+ xor %edx,%edx
+ mov %edx,%fs
+ mov %edx,%gs
+
+ /* Disable paging. */
+ mov %cr0,%edx
+ and $(~X86_CR0_PG),%edx
+ mov %edx,%cr0
+
+ /* Jump to earlier loaded address. */
+ jmp *%edi
+
__start:
cld
cli
@@ -157,7 +374,7 @@ __start:
/* Not available? BDA value will be fine. */
cmovnz MB_mem_lower(%ebx),%edx
- jmp trampoline_setup
+ jmp trampoline_bios_setup
.Lmultiboot2_proto:
/* Skip Multiboot2 information fixed part. */
@@ -169,24 +386,33 @@ __start:
mov %ecx,%edi
sub %ebx,%edi
cmp %edi,MB2_fixed_total_size(%ebx)
- jbe trampoline_setup
+ jbe trampoline_bios_setup
/* Get mem_lower from Multiboot2 information. */
cmpl $MULTIBOOT2_TAG_TYPE_BASIC_MEMINFO,MB2_tag_type(%ecx)
cmove MB2_mem_lower(%ecx),%edx
- je trampoline_setup
+ je .Lmb2_next_tag
+
+ /* EFI IA-32 platforms are not supported. */
+ cmpl $MULTIBOOT2_TAG_TYPE_EFI32,MB2_tag_type(%ecx)
+ je .Lmb2_efi_ia_32
+
+ /* Bootloader shutdown EFI x64 boot services. */
+ cmpl $MULTIBOOT2_TAG_TYPE_EFI64,MB2_tag_type(%ecx)
+ je .Lmb2_no_bs
/* Is it the end of Multiboot2 information? */
cmpl $MULTIBOOT2_TAG_TYPE_END,MB2_tag_type(%ecx)
- je trampoline_setup
+ je trampoline_bios_setup
+.Lmb2_next_tag:
/* Go to next Multiboot2 information tag. */
add MB2_tag_size(%ecx),%ecx
add $(MULTIBOOT2_TAG_ALIGN-1),%ecx
and $~(MULTIBOOT2_TAG_ALIGN-1),%ecx
jmp .Lmb2_tsize
-trampoline_setup:
+trampoline_bios_setup:
/* Set up trampoline segment 64k below EBDA */
movzwl 0x40e,%ecx /* EBDA segment */
cmp $0xa000,%ecx /* sanity check (high) */
@@ -202,28 +428,56 @@ trampoline_setup:
* multiboot structure (if available) and use the smallest.
*/
cmp $0x100,%edx /* is the multiboot value too small? */
- jb 2f /* if so, do not use it */
+ jb trampoline_setup /* if so, do not use it */
shl $10-4,%edx
cmp %ecx,%edx /* compare with BDA value */
cmovb %edx,%ecx /* and use the smaller */
-2: /* Reserve 64kb for the trampoline */
- sub $0x1000,%ecx
+ /* Reserve memory for the trampoline and the low-memory stack. */
+ sub $((TRAMPOLINE_SPACE+TRAMPOLINE_STACK_SPACE)>>4),%ecx
/* From arch/x86/smpboot.c: start_eip had better be page-aligned! */
xor %cl, %cl
+
+trampoline_setup:
shl $4, %ecx
mov %ecx,sym_phys(trampoline_phys)
+ /* Get topmost low-memory stack address. */
+ add $TRAMPOLINE_SPACE,%ecx
+
/* Save the Multiboot info struct (after relocation) for later use. */
mov $sym_phys(cpu0_stack)+1024,%esp
- push %ecx /* Boot trampoline address. */
+ push %ecx /* Topmost low-memory stack address. */
push %ebx /* Multiboot information address. */
push %eax /* Multiboot magic. */
call reloc
mov %eax,sym_phys(multiboot_ptr)
- /* Initialize BSS (no nasty surprises!) */
+ /*
+ * Now trampoline_phys points to the following structure (lowest
+ * address is at the top):
+ *
+ * +------------------------+
+ * | TRAMPOLINE_SPACE |
+ * +- - - - - - - - - - - - +
+ * | mbi struct |
+ * +------------------------+
+ * | TRAMPOLINE_STACK_SPACE |
+ * +------------------------+
+ *
+ * mbi struct lives at the end of TRAMPOLINE_SPACE. The rest of
+ * TRAMPOLINE_SPACE is reserved for trampoline code and data.
+ */
+
+ /*
+ * Do not zero BSS on EFI platform here.
+ * It was initialized earlier.
+ */
+ cmpb $0,sym_phys(efi_platform)
+ jnz 1f
+
+ /* Initialize BSS (no nasty surprises!). */
mov $sym_phys(__bss_start),%edi
mov $sym_phys(__bss_end),%ecx
sub %edi,%ecx
@@ -231,6 +485,7 @@ trampoline_setup:
shr $2,%ecx
rep stosl
+1:
/* Interrogate CPU extended features via CPUID. */
mov $0x80000000,%eax
cpuid
@@ -282,6 +537,10 @@ trampoline_setup:
cmp $sym_phys(__trampoline_seg_stop),%edi
jb 1b
+ /* Do not parse command line on EFI platform here. */
+ cmpb $0,sym_phys(efi_platform)
+ jnz 1f
+
/* Bail if there is no command line to parse. */
mov sym_phys(multiboot_ptr),%ebx
testl $MBI_CMDLINE,MB_flags(%ebx)
@@ -292,9 +551,9 @@ trampoline_setup:
call cmdline_parse_early
1:
- /* Switch to low-memory stack. */
+ /* Switch to low-memory stack which lives at the end of trampoline region. */
mov sym_phys(trampoline_phys),%edi
- lea 0x10000(%edi),%esp
+ lea TRAMPOLINE_SPACE+TRAMPOLINE_STACK_SPACE(%edi),%esp
lea trampoline_boot_cpu_entry-trampoline_start(%edi),%eax
pushl $BOOT_CS32
push %eax
diff --git a/xen/arch/x86/boot/reloc.c b/xen/arch/x86/boot/reloc.c
index 91fab9d..b992678 100644
--- a/xen/arch/x86/boot/reloc.c
+++ b/xen/arch/x86/boot/reloc.c
@@ -16,7 +16,7 @@
* This entry point is entered from xen/arch/x86/boot/head.S with:
* - 0x4(%esp) = MULTIBOOT_MAGIC,
* - 0x8(%esp) = MULTIBOOT_INFORMATION_ADDRESS,
- * - 0xc(%esp) = BOOT_TRAMPOLINE_ADDRESS.
+ * - 0xc(%esp) = TOPMOST_LOW_MEMORY_STACK_ADDRESS.
*/
asm (
" .text \n"
diff --git a/xen/arch/x86/efi/efi-boot.h b/xen/arch/x86/efi/efi-boot.h
index 62c010e..d193847 100644
--- a/xen/arch/x86/efi/efi-boot.h
+++ b/xen/arch/x86/efi/efi-boot.h
@@ -101,6 +101,10 @@ static void __init relocate_trampoline(unsigned long phys)
const s32 *trampoline_ptr;
trampoline_phys = phys;
+
+ if ( !efi_enabled(EFI_LOADER) )
+ return;
+
/* Apply relocations to trampoline. */
for ( trampoline_ptr = __trampoline_rel_start;
trampoline_ptr < __trampoline_rel_stop;
@@ -550,7 +554,12 @@ static void __init efi_arch_memory_setup(void)
/* Allocate space for trampoline (in first Mb). */
cfg.addr = 0x100000;
- cfg.size = trampoline_end - trampoline_start;
+
+ if ( efi_enabled(EFI_LOADER) )
+ cfg.size = trampoline_end - trampoline_start;
+ else
+ cfg.size = TRAMPOLINE_SPACE + TRAMPOLINE_STACK_SPACE;
+
status = efi_bs->AllocatePages(AllocateMaxAddress, EfiLoaderData,
PFN_UP(cfg.size), &cfg.addr);
if ( status == EFI_SUCCESS )
@@ -561,6 +570,9 @@ static void __init efi_arch_memory_setup(void)
PrintStr(L"Trampoline space cannot be allocated; will try fallback.\r\n");
}
+ if ( !efi_enabled(EFI_LOADER) )
+ return;
+
/* Initialise L2 identity-map and boot-map page table entries (16MB). */
for ( i = 0; i < 8; ++i )
{
@@ -653,6 +665,44 @@ static bool_t __init efi_arch_use_config_file(EFI_SYSTEM_TABLE *SystemTable)
static void efi_arch_flush_dcache_area(const void *vaddr, UINTN size) { }
+paddr_t __init efi_multiboot2(EFI_HANDLE ImageHandle, EFI_SYSTEM_TABLE *SystemTable)
+{
+ EFI_GRAPHICS_OUTPUT_PROTOCOL *gop;
+ UINTN cols, gop_mode = ~0, rows;
+
+ __set_bit(EFI_BOOT, &efi_flags);
+ __set_bit(EFI_RS, &efi_flags);
+
+ efi_init(ImageHandle, SystemTable);
+
+ efi_console_set_mode();
+
+ if ( StdOut->QueryMode(StdOut, StdOut->Mode->Mode,
+ &cols, &rows) == EFI_SUCCESS )
+ efi_arch_console_init(cols, rows);
+
+ gop = efi_get_gop();
+
+ if ( gop )
+ gop_mode = efi_find_gop_mode(gop, 0, 0, 0);
+
+ efi_arch_edd();
+ efi_arch_cpu();
+
+ efi_tables();
+ setup_efi_pci();
+ efi_variables();
+ efi_arch_memory_setup();
+
+ if ( gop )
+ efi_set_gop_mode(gop, gop_mode);
+
+ efi_exit_boot(ImageHandle, SystemTable);
+
+ /* Return trampoline address. */
+ return trampoline_phys;
+}
+
/*
* Local variables:
* mode: C
diff --git a/xen/arch/x86/efi/stub.c b/xen/arch/x86/efi/stub.c
index 4158124..8df9ba2 100644
--- a/xen/arch/x86/efi/stub.c
+++ b/xen/arch/x86/efi/stub.c
@@ -3,6 +3,45 @@
#include <xen/init.h>
#include <xen/lib.h>
#include <asm/page.h>
+#include <asm/efibind.h>
+#include <efi/efidef.h>
+#include <efi/eficapsule.h>
+#include <efi/eficon.h>
+#include <efi/efidevp.h>
+#include <efi/efiapi.h>
+
+/*
+ * Here we are in EFI stub. EFI calls are not supported due to lack
+ * of relevant functionality in compiler and/or linker.
+ *
+ * efi_multiboot2() is an exception. Please look below for more details.
+ */
+
+paddr_t __init noreturn efi_multiboot2(EFI_HANDLE ImageHandle,
+ EFI_SYSTEM_TABLE *SystemTable)
+{
+ static const CHAR16 __initconst err[] =
+ L"(XEN) Xen does not have EFI code build in!\r\n(XEN) System halted!\r\n";
+ SIMPLE_TEXT_OUTPUT_INTERFACE *StdErr;
+
+ StdErr = SystemTable->StdErr ? SystemTable->StdErr : SystemTable->ConOut;
+
+ /*
+ * Print error message and halt the system.
+ *
+ * We have to open code MS x64 calling convention
+ * in assembly because here this convention may
+ * not be directly supported by C compiler.
+ */
+ asm volatile(
+ " call *%2 \n"
+ "0: hlt \n"
+ " jmp 0b \n"
+ : "+c" (StdErr), "+d" (err) : "rm" (StdErr->OutputString)
+ : "rax", "r8", "r9", "r10", "r11", "memory");
+
+ unreachable();
+}
bool efi_enabled(unsigned int feature)
{
diff --git a/xen/arch/x86/x86_64/asm-offsets.c b/xen/arch/x86/x86_64/asm-offsets.c
index 92f5d81..f135654 100644
--- a/xen/arch/x86/x86_64/asm-offsets.c
+++ b/xen/arch/x86/x86_64/asm-offsets.c
@@ -175,6 +175,8 @@ void __dummy__(void)
OFFSET(MB2_tag_type, multiboot2_tag_t, type);
OFFSET(MB2_tag_size, multiboot2_tag_t, size);
OFFSET(MB2_mem_lower, multiboot2_tag_basic_meminfo_t, mem_lower);
+ OFFSET(MB2_efi64_st, multiboot2_tag_efi64_t, pointer);
+ OFFSET(MB2_efi64_ih, multiboot2_tag_efi64_ih_t, pointer);
BLANK();
OFFSET(DOMAIN_vm_assist, struct domain, vm_assist);
diff --git a/xen/arch/x86/xen.lds.S b/xen/arch/x86/xen.lds.S
index b0b1c9b..addf2ef 100644
--- a/xen/arch/x86/xen.lds.S
+++ b/xen/arch/x86/xen.lds.S
@@ -331,5 +331,8 @@ ASSERT(IS_ALIGNED(__init_end, PAGE_SIZE), "__init_end misaligned")
ASSERT(IS_ALIGNED(trampoline_start, 4), "trampoline_start misaligned")
ASSERT(IS_ALIGNED(trampoline_end, 4), "trampoline_end misaligned")
-ASSERT(IS_ALIGNED(__bss_start, 4), "__bss_start misaligned")
-ASSERT(IS_ALIGNED(__bss_end, 4), "__bss_end misaligned")
+ASSERT(IS_ALIGNED(__bss_start, 8), "__bss_start misaligned")
+ASSERT(IS_ALIGNED(__bss_end, 8), "__bss_end misaligned")
+
+ASSERT((trampoline_end - trampoline_start) < TRAMPOLINE_SPACE,
+ "not enough room for trampoline")
diff --git a/xen/common/efi/boot.c b/xen/common/efi/boot.c
index 36dbb71..b6cbdad 100644
--- a/xen/common/efi/boot.c
+++ b/xen/common/efi/boot.c
@@ -79,6 +79,17 @@ static size_t wstrlen(const CHAR16 * s);
static int set_color(u32 mask, int bpp, u8 *pos, u8 *sz);
static bool_t match_guid(const EFI_GUID *guid1, const EFI_GUID *guid2);
+static void efi_init(EFI_HANDLE ImageHandle, EFI_SYSTEM_TABLE *SystemTable);
+static void efi_console_set_mode(void);
+static EFI_GRAPHICS_OUTPUT_PROTOCOL *efi_get_gop(void);
+static UINTN efi_find_gop_mode(EFI_GRAPHICS_OUTPUT_PROTOCOL *gop,
+ UINTN cols, UINTN rows, UINTN depth);
+static void efi_tables(void);
+static void setup_efi_pci(void);
+static void efi_variables(void);
+static void efi_set_gop_mode(EFI_GRAPHICS_OUTPUT_PROTOCOL *gop, UINTN gop_mode);
+static void efi_exit_boot(EFI_HANDLE ImageHandle, EFI_SYSTEM_TABLE *SystemTable);
+
static const EFI_BOOT_SERVICES *__initdata efi_bs;
static UINT32 __initdata efi_bs_revision;
static EFI_HANDLE __initdata efi_ih;
diff --git a/xen/include/asm-x86/config.h b/xen/include/asm-x86/config.h
index 6fd84e7..9cd05a2 100644
--- a/xen/include/asm-x86/config.h
+++ b/xen/include/asm-x86/config.h
@@ -73,6 +73,9 @@
#define STACK_ORDER 3
#define STACK_SIZE (PAGE_SIZE << STACK_ORDER)
+#define TRAMPOLINE_STACK_SPACE PAGE_SIZE
+#define TRAMPOLINE_SPACE (KB(64) - TRAMPOLINE_STACK_SPACE)
+
/* Primary stack is restricted to 8kB by guard pages. */
#define PRIMARY_STACK_SIZE 8192
diff --git a/xen/include/xen/config.h b/xen/include/xen/config.h
index 473c5e8..04e4da5 100644
--- a/xen/include/xen/config.h
+++ b/xen/include/xen/config.h
@@ -70,6 +70,7 @@
#define __force
#define __bitwise
+#define KB(_kb) (_AC(_kb, ULL) << 10)
#define MB(_mb) (_AC(_mb, ULL) << 20)
#define GB(_gb) (_AC(_gb, ULL) << 30)
--
1.7.10.4
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply related [flat|nested] 15+ messages in thread* Re: [PATCH v13 4/9] x86: add multiboot2 protocol support for EFI platforms
2017-01-25 22:11 ` [PATCH v13 4/9] x86: add multiboot2 protocol support for EFI platforms Daniel Kiper
@ 2017-01-25 22:20 ` Doug Goldstein
2017-01-25 22:49 ` Daniel Kiper
0 siblings, 1 reply; 15+ messages in thread
From: Doug Goldstein @ 2017-01-25 22:20 UTC (permalink / raw)
To: Daniel Kiper, xen-devel
Cc: jgross, sstabellini, andrew.cooper3, pgnet.dev, ning.sun,
julien.grall, jbeulich, qiaowei.ren, gang.wei, fu.wei
[-- Attachment #1.1.1: Type: text/plain, Size: 1429 bytes --]
On 1/25/17 4:11 PM, Daniel Kiper wrote:
> This way Xen can be loaded on EFI platforms using GRUB2 and
> other boot loaders which support multiboot2 protocol.
>
> Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
> ---
> v13 - suggestions/fixes:
> - move vga_text_buffer and efi_platform to .init.data section
> (suggested by Jan Beulich),
> - reduce number of error branches in EFI code in xen/arch/x86/boot/head.S
> (suggested by Jan Beulich),
> - rename run_bs label to .Lrun_bs
> (suggested by Jan Beulich),
> - align the stack as UEFI spec requires
> (suggested by Jan Beulich),
> - change trampoline region memory layout
> (suggested by Jan Beulich),
> - revert changes in efi_arch_pre_exit_boot()
> (suggested by Jan Beulich),
> - relocate_trampoline() must set trampoline_phys for all bootloaders;
> otherwise fallback allocator is always used if Xen was loaded with
> Multiboot2 protocol,
> - change err type in efi_multiboot2() to "static const CHAR16 __initconst"
> (suggested by Jan Beulich),
> - change asm "g" constraint to "rm" in efi_multiboot2()
> (suggested by Jan Beulich),
> - improve comments
> (suggested by Jan Beulich and Doug Goldstein).
This is a huge change and would really be helpful to have the diff of
what's changed to work from.
--
Doug Goldstein
[-- Attachment #1.2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 959 bytes --]
[-- Attachment #2: Type: text/plain, Size: 127 bytes --]
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply [flat|nested] 15+ messages in thread
* Re: [PATCH v13 4/9] x86: add multiboot2 protocol support for EFI platforms
2017-01-25 22:20 ` Doug Goldstein
@ 2017-01-25 22:49 ` Daniel Kiper
2017-01-31 12:33 ` Jan Beulich
0 siblings, 1 reply; 15+ messages in thread
From: Daniel Kiper @ 2017-01-25 22:49 UTC (permalink / raw)
To: Doug Goldstein
Cc: jgross, sstabellini, andrew.cooper3, pgnet.dev, ning.sun,
julien.grall, jbeulich, xen-devel, qiaowei.ren, gang.wei, fu.wei
On Wed, Jan 25, 2017 at 04:20:30PM -0600, Doug Goldstein wrote:
> On 1/25/17 4:11 PM, Daniel Kiper wrote:
> > This way Xen can be loaded on EFI platforms using GRUB2 and
> > other boot loaders which support multiboot2 protocol.
> >
> > Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
> > ---
> > v13 - suggestions/fixes:
> > - move vga_text_buffer and efi_platform to .init.data section
> > (suggested by Jan Beulich),
> > - reduce number of error branches in EFI code in xen/arch/x86/boot/head.S
> > (suggested by Jan Beulich),
> > - rename run_bs label to .Lrun_bs
> > (suggested by Jan Beulich),
> > - align the stack as UEFI spec requires
> > (suggested by Jan Beulich),
> > - change trampoline region memory layout
> > (suggested by Jan Beulich),
> > - revert changes in efi_arch_pre_exit_boot()
> > (suggested by Jan Beulich),
> > - relocate_trampoline() must set trampoline_phys for all bootloaders;
> > otherwise fallback allocator is always used if Xen was loaded with
> > Multiboot2 protocol,
> > - change err type in efi_multiboot2() to "static const CHAR16 __initconst"
> > (suggested by Jan Beulich),
> > - change asm "g" constraint to "rm" in efi_multiboot2()
> > (suggested by Jan Beulich),
> > - improve comments
> > (suggested by Jan Beulich and Doug Goldstein).
>
> This is a huge change and would really be helpful to have the diff of
> what's changed to work from.
Please look below...
Daniel
diff --git a/xen/arch/x86/boot/head.S b/xen/arch/x86/boot/head.S
index b8f727a..2ecdcb3 100644
--- a/xen/arch/x86/boot/head.S
+++ b/xen/arch/x86/boot/head.S
@@ -109,13 +109,6 @@ gdt_boot_descr:
.long sym_phys(trampoline_gdt)
.long 0 /* Needed for 64-bit lgdt */
- .align 4
-vga_text_buffer:
- .long 0xb8000
-
-efi_platform:
- .byte 0
-
.Lbad_cpu_msg: .asciz "ERR: Not a 64-bit CPU!"
.Lbad_ldr_msg: .asciz "ERR: Not a Multiboot bootloader!"
.Lbad_ldr_nbs: .asciz "ERR: Bootloader shutdown EFI x64 boot services!"
@@ -123,6 +116,15 @@ efi_platform:
.Lbad_ldr_nih: .asciz "ERR: EFI ImageHandle is not provided by bootloader!"
.Lbad_efi_msg: .asciz "ERR: EFI IA-32 platforms are not supported!"
+ .section .init.data, "a", @progbits
+ .align 4
+
+vga_text_buffer:
+ .long 0xb8000
+
+efi_platform:
+ .byte 0
+
.section .init.text, "ax", @progbits
bad_cpu:
@@ -170,6 +172,12 @@ not_multiboot:
.code64
__efi64_mb2_start:
+ /*
+ * Multiboot2 spec says that here CPU is in 64-bit mode. However, there
+ * is also guarantee that all code and data is always put by the bootloader
+ * below 4 GiB. Hence, we can safely use in most cases 32-bit addressing.
+ */
+
cld
/* VGA is not available on EFI platforms. */
@@ -180,7 +188,7 @@ __efi64_mb2_start:
je .Lefi_multiboot2_proto
/* Jump to not_multiboot after switching CPU to x86_32 mode. */
- lea not_multiboot(%rip),%edi
+ lea not_multiboot(%rip),%r15d
jmp x86_32_switch
.Lefi_multiboot2_proto:
@@ -197,7 +205,7 @@ __efi64_mb2_start:
mov %ecx,%r8d
sub %ebx,%r8d
cmp %r8d,MB2_fixed_total_size(%rbx)
- jbe run_bs
+ jbe .Lrun_bs
/* Are EFI boot services available? */
cmpl $MULTIBOOT2_TAG_TYPE_EFI_BS,MB2_tag_type(%rcx)
@@ -226,7 +234,7 @@ __efi64_mb2_start:
/* Is it the end of Multiboot2 information? */
cmpl $MULTIBOOT2_TAG_TYPE_END,MB2_tag_type(%rcx)
- je run_bs
+ je .Lrun_bs
.Lefi_mb2_next_tag:
/* Go to next Multiboot2 information tag. */
@@ -235,34 +243,32 @@ __efi64_mb2_start:
and $~(MULTIBOOT2_TAG_ALIGN-1),%ecx
jmp .Lefi_mb2_tsize
-run_bs:
+.Lrun_bs:
/* Are EFI boot services available? */
cmpb $0,efi_platform(%rip)
- jnz 0f
/* Jump to .Lmb2_no_bs after switching CPU to x86_32 mode. */
- lea .Lmb2_no_bs(%rip),%edi
- jmp x86_32_switch
+ lea .Lmb2_no_bs(%rip),%r15d
+ jz x86_32_switch
-0:
/* Is EFI SystemTable address provided by boot loader? */
test %rsi,%rsi
- jnz 1f
/* Jump to .Lmb2_no_st after switching CPU to x86_32 mode. */
- lea .Lmb2_no_st(%rip),%edi
- jmp x86_32_switch
+ lea .Lmb2_no_st(%rip),%r15d
+ jz x86_32_switch
-1:
/* Is EFI ImageHandle address provided by boot loader? */
test %rdi,%rdi
- jnz 2f
/* Jump to .Lmb2_no_ih after switching CPU to x86_32 mode. */
- lea .Lmb2_no_ih(%rip),%edi
- jmp x86_32_switch
+ lea .Lmb2_no_ih(%rip),%r15d
+ jz x86_32_switch
+
+ /* Align the stack as UEFI spec requires. */
+ add $15,%rsp
+ and $~15,%rsp
-2:
push %rax
push %rdi
@@ -280,13 +286,13 @@ run_bs:
pop %rdi
+ /* Align the stack as UEFI spec requires. */
+ push %rdi
+
/*
* efi_multiboot2() is called according to System V AMD64 ABI:
- * - IN: %rdi - EFI ImageHandle, %rsi - EFI SystemTable,
- * - OUT: %rax - highest allocated memory address below 1 MiB;
- * memory below this address is used for trampoline
- * stack, trampoline itself and as a storage for
- * mbi struct created in reloc().
+ * - IN: %rdi - EFI ImageHandle, %rsi - EFI SystemTable,
+ * - OUT: %rax - trampoline address.
*
* MULTIBOOT2_TAG_TYPE_BASIC_MEMINFO tag is not provided
* on EFI platforms. Hence, it could not be used like
@@ -298,12 +304,15 @@ run_bs:
shr $4,%eax
mov %eax,%ecx
+ pop %rdi
pop %rax
/* Jump to trampoline_setup after switching CPU to x86_32 mode. */
- lea trampoline_setup(%rip),%edi
+ lea trampoline_setup(%rip),%r15d
x86_32_switch:
+ mov %r15d,%edi
+
cli
/* Initialize GDTR. */
@@ -424,26 +433,44 @@ trampoline_bios_setup:
cmp %ecx,%edx /* compare with BDA value */
cmovb %edx,%ecx /* and use the smaller */
- /* Reserve memory for the trampoline. */
- sub $((MB_TRAMPOLINE_SIZE+MB_TRAMPOLINE_STACK_SIZE)>>4),%ecx
+ /* Reserve memory for the trampoline and the low-memory stack. */
+ sub $((TRAMPOLINE_SPACE+TRAMPOLINE_STACK_SPACE)>>4),%ecx
/* From arch/x86/smpboot.c: start_eip had better be page-aligned! */
xor %cl, %cl
trampoline_setup:
- /* Save trampoline address for later use. */
shl $4, %ecx
mov %ecx,sym_phys(trampoline_phys)
+ /* Get topmost low-memory stack address. */
+ add $TRAMPOLINE_SPACE,%ecx
+
/* Save the Multiboot info struct (after relocation) for later use. */
mov $sym_phys(cpu0_stack)+1024,%esp
- push %ecx /* Boot trampoline address. */
+ push %ecx /* Topmost low-memory stack address. */
push %ebx /* Multiboot information address. */
push %eax /* Multiboot magic. */
call reloc
mov %eax,sym_phys(multiboot_ptr)
/*
+ * Now trampoline_phys points to the following structure (lowest
+ * address is at the top):
+ *
+ * +------------------------+
+ * | TRAMPOLINE_SPACE |
+ * +- - - - - - - - - - - - +
+ * | mbi struct |
+ * +------------------------+
+ * | TRAMPOLINE_STACK_SPACE |
+ * +------------------------+
+ *
+ * mbi struct lives at the end of TRAMPOLINE_SPACE. The rest of
+ * TRAMPOLINE_SPACE is reserved for trampoline code and data.
+ */
+
+ /*
* Do not zero BSS on EFI platform here.
* It was initialized earlier.
*/
@@ -526,7 +553,7 @@ trampoline_setup:
1:
/* Switch to low-memory stack which lives at the end of trampoline region. */
mov sym_phys(trampoline_phys),%edi
- lea MB_TRAMPOLINE_SIZE+MB_TRAMPOLINE_STACK_SIZE(%edi),%esp
+ lea TRAMPOLINE_SPACE+TRAMPOLINE_STACK_SPACE(%edi),%esp
lea trampoline_boot_cpu_entry-trampoline_start(%edi),%eax
pushl $BOOT_CS32
push %eax
diff --git a/xen/arch/x86/boot/reloc.c b/xen/arch/x86/boot/reloc.c
index 0f2e372..b992678 100644
--- a/xen/arch/x86/boot/reloc.c
+++ b/xen/arch/x86/boot/reloc.c
@@ -16,7 +16,7 @@
* This entry point is entered from xen/arch/x86/boot/head.S with:
* - 0x4(%esp) = MULTIBOOT_MAGIC,
* - 0x8(%esp) = MULTIBOOT_INFORMATION_ADDRESS,
- * - 0xc(%esp) = BOOT_TRAMPOLINE_ADDRESS.
+ * - 0xc(%esp) = TOPMOST_LOW_MEMORY_STACK_ADDRESS.
*/
asm (
" .text \n"
@@ -235,3 +235,13 @@ multiboot_info_t __stdcall *reloc(u32 mb_magic, u32 mbi_in, u32 trampoline)
else
return mbi_reloc(mbi_in);
}
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
diff --git a/xen/arch/x86/efi/efi-boot.h b/xen/arch/x86/efi/efi-boot.h
index c1285ad..d193847 100644
--- a/xen/arch/x86/efi/efi-boot.h
+++ b/xen/arch/x86/efi/efi-boot.h
@@ -100,10 +100,11 @@ static void __init relocate_trampoline(unsigned long phys)
{
const s32 *trampoline_ptr;
- if ( !efi_enabled(EFI_LOADER) || trampoline_phys )
+ trampoline_phys = phys;
+
+ if ( !efi_enabled(EFI_LOADER) )
return;
- trampoline_phys = phys;
/* Apply relocations to trampoline. */
for ( trampoline_ptr = __trampoline_rel_start;
trampoline_ptr < __trampoline_rel_stop;
@@ -213,10 +214,12 @@ static void *__init efi_arch_allocate_mmap_buffer(UINTN map_size)
static void __init efi_arch_pre_exit_boot(void)
{
- if ( !cfg.addr )
- blexit(L"No memory for trampoline");
-
- relocate_trampoline(cfg.addr);
+ if ( !trampoline_phys )
+ {
+ if ( !cfg.addr )
+ blexit(L"No memory for trampoline");
+ relocate_trampoline(cfg.addr);
+ }
}
static void __init noreturn efi_arch_post_exit_boot(void)
@@ -555,7 +558,7 @@ static void __init efi_arch_memory_setup(void)
if ( efi_enabled(EFI_LOADER) )
cfg.size = trampoline_end - trampoline_start;
else
- cfg.size = MB_TRAMPOLINE_SIZE + MB_TRAMPOLINE_STACK_SIZE + MBI_SIZE;
+ cfg.size = TRAMPOLINE_SPACE + TRAMPOLINE_STACK_SPACE;
status = efi_bs->AllocatePages(AllocateMaxAddress, EfiLoaderData,
PFN_UP(cfg.size), &cfg.addr);
@@ -696,8 +699,8 @@ paddr_t __init efi_multiboot2(EFI_HANDLE ImageHandle, EFI_SYSTEM_TABLE *SystemTa
efi_exit_boot(ImageHandle, SystemTable);
- /* Return highest allocated memory address below 1 MiB. */
- return cfg.addr + cfg.size;
+ /* Return trampoline address. */
+ return trampoline_phys;
}
/*
diff --git a/xen/arch/x86/efi/stub.c b/xen/arch/x86/efi/stub.c
index b81adc0..8df9ba2 100644
--- a/xen/arch/x86/efi/stub.c
+++ b/xen/arch/x86/efi/stub.c
@@ -20,7 +20,8 @@
paddr_t __init noreturn efi_multiboot2(EFI_HANDLE ImageHandle,
EFI_SYSTEM_TABLE *SystemTable)
{
- CHAR16 *err = L"Xen does not have EFI code build in!!!\r\nSystem halted!!!\r\n";
+ static const CHAR16 __initconst err[] =
+ L"(XEN) Xen does not have EFI code build in!\r\n(XEN) System halted!\r\n";
SIMPLE_TEXT_OUTPUT_INTERFACE *StdErr;
StdErr = SystemTable->StdErr ? SystemTable->StdErr : SystemTable->ConOut;
@@ -36,7 +37,7 @@ paddr_t __init noreturn efi_multiboot2(EFI_HANDLE ImageHandle,
" call *%2 \n"
"0: hlt \n"
" jmp 0b \n"
- : "+c" (StdErr), "+d" (err) : "g" (StdErr->OutputString)
+ : "+c" (StdErr), "+d" (err) : "rm" (StdErr->OutputString)
: "rax", "r8", "r9", "r10", "r11", "memory");
unreachable();
diff --git a/xen/arch/x86/xen.lds.S b/xen/arch/x86/xen.lds.S
index 3a02b2b..addf2ef 100644
--- a/xen/arch/x86/xen.lds.S
+++ b/xen/arch/x86/xen.lds.S
@@ -334,5 +334,5 @@ ASSERT(IS_ALIGNED(trampoline_end, 4), "trampoline_end misaligned")
ASSERT(IS_ALIGNED(__bss_start, 8), "__bss_start misaligned")
ASSERT(IS_ALIGNED(__bss_end, 8), "__bss_end misaligned")
-ASSERT((trampoline_end - trampoline_start) < MB_TRAMPOLINE_SIZE,
+ASSERT((trampoline_end - trampoline_start) < TRAMPOLINE_SPACE,
"not enough room for trampoline")
diff --git a/xen/include/asm-x86/config.h b/xen/include/asm-x86/config.h
index a86ea12..9cd05a2 100644
--- a/xen/include/asm-x86/config.h
+++ b/xen/include/asm-x86/config.h
@@ -73,10 +73,8 @@
#define STACK_ORDER 3
#define STACK_SIZE (PAGE_SIZE << STACK_ORDER)
-#define MB_TRAMPOLINE_STACK_SIZE PAGE_SIZE
-#define MB_TRAMPOLINE_SIZE (KB(64) - MB_TRAMPOLINE_STACK_SIZE)
-
-#define MBI_SIZE (2 * PAGE_SIZE)
+#define TRAMPOLINE_STACK_SPACE PAGE_SIZE
+#define TRAMPOLINE_SPACE (KB(64) - TRAMPOLINE_STACK_SPACE)
/* Primary stack is restricted to 8kB by guard pages. */
#define PRIMARY_STACK_SIZE 8192
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply related [flat|nested] 15+ messages in thread* Re: [PATCH v13 4/9] x86: add multiboot2 protocol support for EFI platforms
2017-01-25 22:49 ` Daniel Kiper
@ 2017-01-31 12:33 ` Jan Beulich
2017-01-31 14:23 ` Daniel Kiper
0 siblings, 1 reply; 15+ messages in thread
From: Jan Beulich @ 2017-01-31 12:33 UTC (permalink / raw)
To: Daniel Kiper
Cc: Juergen Gross, sstabellini, andrew.cooper3, Doug Goldstein,
pgnet.dev, ning.sun, julien.grall, xen-devel, qiaowei.ren,
gang.wei, fu.wei
>>> On 25.01.17 at 23:49, <daniel.kiper@oracle.com> wrote:
> On Wed, Jan 25, 2017 at 04:20:30PM -0600, Doug Goldstein wrote:
>> This is a huge change and would really be helpful to have the diff of
>> what's changed to work from.
>
> Please look below...
Thanks for providing this - I'll comment this rather than the full patch:
> @@ -123,6 +116,15 @@ efi_platform:
> .Lbad_ldr_nih: .asciz "ERR: EFI ImageHandle is not provided by bootloader!"
> .Lbad_efi_msg: .asciz "ERR: EFI IA-32 platforms are not supported!"
>
> + .section .init.data, "a", @progbits
This needs to be a writable section.
> @@ -170,6 +172,12 @@ not_multiboot:
> .code64
>
> __efi64_mb2_start:
> + /*
> + * Multiboot2 spec says that here CPU is in 64-bit mode. However, there
> + * is also guarantee that all code and data is always put by the bootloader
> + * below 4 GiB. Hence, we can safely use in most cases 32-bit addressing.
> + */
"use 32-bit addressing" is misleading: I don't think you use any such,
since - as pointed out during earlier review - this would needlessly
cause 0x67 prefixes to be emitted. Instead what you mean is that
we can safely truncate addresses.
> @@ -180,7 +188,7 @@ __efi64_mb2_start:
> je .Lefi_multiboot2_proto
>
> /* Jump to not_multiboot after switching CPU to x86_32 mode. */
> - lea not_multiboot(%rip),%edi
> + lea not_multiboot(%rip),%r15d
In cases like this, where a REX prefix is needed anyway, please
use the full register unless you strictly need it zero-extended
from 32 bits.
> + /* Align the stack as UEFI spec requires. */
> + add $15,%rsp
> + and $~15,%rsp
How come you _add_ something here first? Simply do the AND and
be done. Also please extend the comment along the lines of what
I had asked for before: To warn of future changes to the number
of items pushed onto the stack below.
> @@ -280,13 +286,13 @@ run_bs:
>
> pop %rdi
>
> + /* Align the stack as UEFI spec requires. */
> + push %rdi
Please combine the two into "mov (%rsp), %rdi" and make the
comment say "Keep the stack aligned; don't pop a single item
off it" or some such.
> @@ -424,26 +433,44 @@ trampoline_bios_setup:
> cmp %ecx,%edx /* compare with BDA value */
> cmovb %edx,%ecx /* and use the smaller */
>
> - /* Reserve memory for the trampoline. */
> - sub $((MB_TRAMPOLINE_SIZE+MB_TRAMPOLINE_STACK_SIZE)>>4),%ecx
> + /* Reserve memory for the trampoline and the low-memory stack. */
> + sub $((TRAMPOLINE_SPACE+TRAMPOLINE_STACK_SPACE)>>4),%ecx
>
> /* From arch/x86/smpboot.c: start_eip had better be page-aligned! */
> xor %cl, %cl
>
> trampoline_setup:
> - /* Save trampoline address for later use. */
> shl $4, %ecx
> mov %ecx,sym_phys(trampoline_phys)
>
> + /* Get topmost low-memory stack address. */
> + add $TRAMPOLINE_SPACE,%ecx
The top-most address of the stack is
%ecx + TRAMPOLINE_SPACE + TRAMPOLINE_STACK_SPACE - 1.
Please don't add misleading comments.
> /* Save the Multiboot info struct (after relocation) for later use. */
> mov $sym_phys(cpu0_stack)+1024,%esp
> - push %ecx /* Boot trampoline address. */
> + push %ecx /* Topmost low-memory stack address. */
> push %ebx /* Multiboot information address. */
> push %eax /* Multiboot magic. */
> call reloc
> mov %eax,sym_phys(multiboot_ptr)
>
> /*
> + * Now trampoline_phys points to the following structure (lowest
> + * address is at the top):
> + *
> + * +------------------------+
> + * | TRAMPOLINE_SPACE |
> + * +- - - - - - - - - - - - +
> + * | mbi struct |
> + * +------------------------+
> + * | TRAMPOLINE_STACK_SPACE |
> + * +------------------------+
> + *
> + * mbi struct lives at the end of TRAMPOLINE_SPACE. The rest of
> + * TRAMPOLINE_SPACE is reserved for trampoline code and data.
> + */
Please can you clarify here that the MBI data grows downwards
from the beginning of the stack to the end of the trampoline?
> @@ -696,8 +699,8 @@ paddr_t __init efi_multiboot2(EFI_HANDLE ImageHandle, EFI_SYSTEM_TABLE *SystemTa
>
> efi_exit_boot(ImageHandle, SystemTable);
>
> - /* Return highest allocated memory address below 1 MiB. */
> - return cfg.addr + cfg.size;
> + /* Return trampoline address. */
> + return trampoline_phys;
> }
With this it would be less confusing if you move the trampoline_setup
label down a few more lines. Perhaps the function here could then
return void.
> --- a/xen/arch/x86/efi/stub.c
> +++ b/xen/arch/x86/efi/stub.c
> @@ -20,7 +20,8 @@
> paddr_t __init noreturn efi_multiboot2(EFI_HANDLE ImageHandle,
> EFI_SYSTEM_TABLE *SystemTable)
> {
> - CHAR16 *err = L"Xen does not have EFI code build in!!!\r\nSystem halted!!!\r\n";
> + static const CHAR16 __initconst err[] =
> + L"(XEN) Xen does not have EFI code build in!\r\n(XEN) System halted!\r\n";
Why did you add these (XEN) prefixes?
> --- a/xen/arch/x86/xen.lds.S
> +++ b/xen/arch/x86/xen.lds.S
> @@ -334,5 +334,5 @@ ASSERT(IS_ALIGNED(trampoline_end, 4), "trampoline_end
> misaligned")
> ASSERT(IS_ALIGNED(__bss_start, 8), "__bss_start misaligned")
> ASSERT(IS_ALIGNED(__bss_end, 8), "__bss_end misaligned")
>
> -ASSERT((trampoline_end - trampoline_start) < MB_TRAMPOLINE_SIZE,
> +ASSERT((trampoline_end - trampoline_start) < TRAMPOLINE_SPACE,
> "not enough room for trampoline")
Didn't you mean to make sure there are at least two pages for
MBI data?
Jan
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply [flat|nested] 15+ messages in thread* Re: [PATCH v13 4/9] x86: add multiboot2 protocol support for EFI platforms
2017-01-31 12:33 ` Jan Beulich
@ 2017-01-31 14:23 ` Daniel Kiper
2017-01-31 15:14 ` Jan Beulich
0 siblings, 1 reply; 15+ messages in thread
From: Daniel Kiper @ 2017-01-31 14:23 UTC (permalink / raw)
To: Jan Beulich
Cc: Juergen Gross, sstabellini, andrew.cooper3, Doug Goldstein,
pgnet.dev, ning.sun, julien.grall, xen-devel, qiaowei.ren,
gang.wei, fu.wei
On Tue, Jan 31, 2017 at 05:33:12AM -0700, Jan Beulich wrote:
> >>> On 25.01.17 at 23:49, <daniel.kiper@oracle.com> wrote:
> > On Wed, Jan 25, 2017 at 04:20:30PM -0600, Doug Goldstein wrote:
> >> This is a huge change and would really be helpful to have the diff of
> >> what's changed to work from.
> >
> > Please look below...
>
> Thanks for providing this - I'll comment this rather than the full patch:
If you wish I can do that next time too.
> > @@ -123,6 +116,15 @@ efi_platform:
> > .Lbad_ldr_nih: .asciz "ERR: EFI ImageHandle is not provided by bootloader!"
> > .Lbad_efi_msg: .asciz "ERR: EFI IA-32 platforms are not supported!"
> >
> > + .section .init.data, "a", @progbits
>
> This needs to be a writable section.
AIUI, it is by default but if you wish I can replace "a" with "aw" here.
> > @@ -170,6 +172,12 @@ not_multiboot:
> > .code64
> >
> > __efi64_mb2_start:
> > + /*
> > + * Multiboot2 spec says that here CPU is in 64-bit mode. However, there
> > + * is also guarantee that all code and data is always put by the bootloader
> > + * below 4 GiB. Hence, we can safely use in most cases 32-bit addressing.
> > + */
>
> "use 32-bit addressing" is misleading: I don't think you use any such,
> since - as pointed out during earlier review - this would needlessly
> cause 0x67 prefixes to be emitted. Instead what you mean is that
> we can safely truncate addresses.
OK.
> > @@ -180,7 +188,7 @@ __efi64_mb2_start:
> > je .Lefi_multiboot2_proto
> >
> > /* Jump to not_multiboot after switching CPU to x86_32 mode. */
> > - lea not_multiboot(%rip),%edi
> > + lea not_multiboot(%rip),%r15d
>
> In cases like this, where a REX prefix is needed anyway, please
> use the full register unless you strictly need it zero-extended
> from 32 bits.
OK.
> > + /* Align the stack as UEFI spec requires. */
> > + add $15,%rsp
> > + and $~15,%rsp
>
> How come you _add_ something here first? Simply do the AND and
> be done. Also please extend the comment along the lines of what
Facepalm! Err... Why I forgot here that stack grows downward...
> I had asked for before: To warn of future changes to the number
> of items pushed onto the stack below.
OK.
> > @@ -280,13 +286,13 @@ run_bs:
> >
> > pop %rdi
> >
> > + /* Align the stack as UEFI spec requires. */
> > + push %rdi
>
> Please combine the two into "mov (%rsp), %rdi" and make the
> comment say "Keep the stack aligned; don't pop a single item
> off it" or some such.
OK.
> > @@ -424,26 +433,44 @@ trampoline_bios_setup:
> > cmp %ecx,%edx /* compare with BDA value */
> > cmovb %edx,%ecx /* and use the smaller */
> >
> > - /* Reserve memory for the trampoline. */
> > - sub $((MB_TRAMPOLINE_SIZE+MB_TRAMPOLINE_STACK_SIZE)>>4),%ecx
> > + /* Reserve memory for the trampoline and the low-memory stack. */
> > + sub $((TRAMPOLINE_SPACE+TRAMPOLINE_STACK_SPACE)>>4),%ecx
> >
> > /* From arch/x86/smpboot.c: start_eip had better be page-aligned! */
> > xor %cl, %cl
> >
> > trampoline_setup:
> > - /* Save trampoline address for later use. */
> > shl $4, %ecx
> > mov %ecx,sym_phys(trampoline_phys)
> >
> > + /* Get topmost low-memory stack address. */
> > + add $TRAMPOLINE_SPACE,%ecx
>
> The top-most address of the stack is
> %ecx + TRAMPOLINE_SPACE + TRAMPOLINE_STACK_SPACE - 1.
> Please don't add misleading comments.
Right, it is misleading. Do you think that:
Get the lowest low-memory stack address.
...is better?
> > /* Save the Multiboot info struct (after relocation) for later use. */
> > mov $sym_phys(cpu0_stack)+1024,%esp
> > - push %ecx /* Boot trampoline address. */
> > + push %ecx /* Topmost low-memory stack address. */
> > push %ebx /* Multiboot information address. */
> > push %eax /* Multiboot magic. */
> > call reloc
> > mov %eax,sym_phys(multiboot_ptr)
> >
> > /*
> > + * Now trampoline_phys points to the following structure (lowest
> > + * address is at the top):
> > + *
> > + * +------------------------+
> > + * | TRAMPOLINE_SPACE |
> > + * +- - - - - - - - - - - - +
> > + * | mbi struct |
> > + * +------------------------+
> > + * | TRAMPOLINE_STACK_SPACE |
> > + * +------------------------+
> > + *
> > + * mbi struct lives at the end of TRAMPOLINE_SPACE. The rest of
> > + * TRAMPOLINE_SPACE is reserved for trampoline code and data.
> > + */
>
> Please can you clarify here that the MBI data grows downwards
> from the beginning of the stack to the end of the trampoline?
OK, but I think that "beginning of the stack" should be replaced
with "the end of TRAMPOLINE_SPACE" here.
> > @@ -696,8 +699,8 @@ paddr_t __init efi_multiboot2(EFI_HANDLE ImageHandle, EFI_SYSTEM_TABLE *SystemTa
> >
> > efi_exit_boot(ImageHandle, SystemTable);
> >
> > - /* Return highest allocated memory address below 1 MiB. */
> > - return cfg.addr + cfg.size;
> > + /* Return trampoline address. */
> > + return trampoline_phys;
> > }
>
> With this it would be less confusing if you move the trampoline_setup
> label down a few more lines. Perhaps the function here could then
> return void.
If you wish.
> > --- a/xen/arch/x86/efi/stub.c
> > +++ b/xen/arch/x86/efi/stub.c
> > @@ -20,7 +20,8 @@
> > paddr_t __init noreturn efi_multiboot2(EFI_HANDLE ImageHandle,
> > EFI_SYSTEM_TABLE *SystemTable)
> > {
> > - CHAR16 *err = L"Xen does not have EFI code build in!!!\r\nSystem halted!!!\r\n";
> > + static const CHAR16 __initconst err[] =
> > + L"(XEN) Xen does not have EFI code build in!\r\n(XEN) System halted!\r\n";
>
> Why did you add these (XEN) prefixes?
To align message format with messages printed from most places. And I realized
that it will be nice to do the same thing in head.S and the rest of EFI code.
This way it is much easier to differentiate between a bootloader and Xen messages.
Though it begs another patch series.
> > --- a/xen/arch/x86/xen.lds.S
> > +++ b/xen/arch/x86/xen.lds.S
> > @@ -334,5 +334,5 @@ ASSERT(IS_ALIGNED(trampoline_end, 4), "trampoline_end
> > misaligned")
> > ASSERT(IS_ALIGNED(__bss_start, 8), "__bss_start misaligned")
> > ASSERT(IS_ALIGNED(__bss_end, 8), "__bss_end misaligned")
> >
> > -ASSERT((trampoline_end - trampoline_start) < MB_TRAMPOLINE_SIZE,
> > +ASSERT((trampoline_end - trampoline_start) < TRAMPOLINE_SPACE,
> > "not enough room for trampoline")
>
> Didn't you mean to make sure there are at least two pages for
> MBI data?
Do you wish plain number here or constant like MBI_SIZE defined somewhere.
I think that constant is better thing.
Daniel
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply [flat|nested] 15+ messages in thread* Re: [PATCH v13 4/9] x86: add multiboot2 protocol support for EFI platforms
2017-01-31 14:23 ` Daniel Kiper
@ 2017-01-31 15:14 ` Jan Beulich
0 siblings, 0 replies; 15+ messages in thread
From: Jan Beulich @ 2017-01-31 15:14 UTC (permalink / raw)
To: Daniel Kiper
Cc: Juergen Gross, sstabellini, andrew.cooper3, Doug Goldstein,
pgnet.dev, ning.sun, julien.grall, xen-devel, qiaowei.ren,
gang.wei, fu.wei
>>> On 31.01.17 at 15:23, <daniel.kiper@oracle.com> wrote:
> On Tue, Jan 31, 2017 at 05:33:12AM -0700, Jan Beulich wrote:
>> >>> On 25.01.17 at 23:49, <daniel.kiper@oracle.com> wrote:
>> > On Wed, Jan 25, 2017 at 04:20:30PM -0600, Doug Goldstein wrote:
>> > @@ -123,6 +116,15 @@ efi_platform:
>> > .Lbad_ldr_nih: .asciz "ERR: EFI ImageHandle is not provided by bootloader!"
>> > .Lbad_efi_msg: .asciz "ERR: EFI IA-32 platforms are not supported!"
>> >
>> > + .section .init.data, "a", @progbits
>>
>> This needs to be a writable section.
>
> AIUI, it is by default but if you wish I can replace "a" with "aw" here.
To me it would smell like a binutils bug if any flag was added despite
the explicit setting here. Things would be different if you omitted
those arguments.
>> > + /* Get topmost low-memory stack address. */
>> > + add $TRAMPOLINE_SPACE,%ecx
>>
>> The top-most address of the stack is
>> %ecx + TRAMPOLINE_SPACE + TRAMPOLINE_STACK_SPACE - 1.
>> Please don't add misleading comments.
>
> Right, it is misleading. Do you think that:
>
> Get the lowest low-memory stack address.
>
> ...is better?
That or "bottom-most" (to avoid the double "low").
>> > /*
>> > + * Now trampoline_phys points to the following structure (lowest
>> > + * address is at the top):
>> > + *
>> > + * +------------------------+
>> > + * | TRAMPOLINE_SPACE |
>> > + * +- - - - - - - - - - - - +
>> > + * | mbi struct |
>> > + * +------------------------+
>> > + * | TRAMPOLINE_STACK_SPACE |
>> > + * +------------------------+
>> > + *
>> > + * mbi struct lives at the end of TRAMPOLINE_SPACE. The rest of
>> > + * TRAMPOLINE_SPACE is reserved for trampoline code and data.
>> > + */
>>
>> Please can you clarify here that the MBI data grows downwards
>> from the beginning of the stack to the end of the trampoline?
>
> OK, but I think that "beginning of the stack" should be replaced
> with "the end of TRAMPOLINE_SPACE" here.
That would be in lines with the #define-s, but not with the drawing
above (which btw also applies to the comment that's there above).
>> > --- a/xen/arch/x86/efi/stub.c
>> > +++ b/xen/arch/x86/efi/stub.c
>> > @@ -20,7 +20,8 @@
>> > paddr_t __init noreturn efi_multiboot2(EFI_HANDLE ImageHandle,
>> > EFI_SYSTEM_TABLE *SystemTable)
>> > {
>> > - CHAR16 *err = L"Xen does not have EFI code build in!!!\r\nSystem halted!!!\r\n";
>> > + static const CHAR16 __initconst err[] =
>> > + L"(XEN) Xen does not have EFI code build in!\r\n(XEN) System halted!\r\n";
>>
>> Why did you add these (XEN) prefixes?
>
> To align message format with messages printed from most places. And I realized
> that it will be nice to do the same thing in head.S and the rest of EFI code.
> This way it is much easier to differentiate between a bootloader and Xen messages.
I disagree. Those prefixes should be used only for messages ending
up in Xen's log.
>> > --- a/xen/arch/x86/xen.lds.S
>> > +++ b/xen/arch/x86/xen.lds.S
>> > @@ -334,5 +334,5 @@ ASSERT(IS_ALIGNED(trampoline_end, 4), "trampoline_end
>> > misaligned")
>> > ASSERT(IS_ALIGNED(__bss_start, 8), "__bss_start misaligned")
>> > ASSERT(IS_ALIGNED(__bss_end, 8), "__bss_end misaligned")
>> >
>> > -ASSERT((trampoline_end - trampoline_start) < MB_TRAMPOLINE_SIZE,
>> > +ASSERT((trampoline_end - trampoline_start) < TRAMPOLINE_SPACE,
>> > "not enough room for trampoline")
>>
>> Didn't you mean to make sure there are at least two pages for
>> MBI data?
>
> Do you wish plain number here or constant like MBI_SIZE defined somewhere.
> I think that constant is better thing.
I'd prefer MBI_SPACE_MIN (or whatever else making clear that this
is a bound, not an exact size).
Jan
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply [flat|nested] 15+ messages in thread
* [PATCH v13 5/9] x86: change default load address from 1 MiB to 2 MiB
2017-01-25 22:11 [PATCH v13 0/9] x86: multiboot2 protocol support Daniel Kiper
` (3 preceding siblings ...)
2017-01-25 22:11 ` [PATCH v13 4/9] x86: add multiboot2 protocol support for EFI platforms Daniel Kiper
@ 2017-01-25 22:11 ` Daniel Kiper
2017-01-25 22:11 ` [PATCH v13 6/9] x86/setup: use XEN_IMG_OFFSET instead of Daniel Kiper
` (3 subsequent siblings)
8 siblings, 0 replies; 15+ messages in thread
From: Daniel Kiper @ 2017-01-25 22:11 UTC (permalink / raw)
To: xen-devel
Cc: jgross, sstabellini, andrew.cooper3, cardoe, pgnet.dev, ning.sun,
julien.grall, jbeulich, qiaowei.ren, gang.wei, fu.wei
Subsequent patches introducing relocatable early boot code play with
page tables using 2 MiB huge pages. If load address is not aligned at
2 MiB then code touching such page tables must have special cases for
start and end of Xen image memory region. So, let's make life easier
and move default load address from 1 MiB to 2 MiB. This way page table
code will be nice and easy. Hence, there is a chance that it will be
less error prone too... :-)))
Additionally, drop first 2 MiB mapping from Xen image mapping.
It is no longer needed.
Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Doug Goldstein <cardoe@cardoe.com>
---
v8 - suggestions/fixes:
- drop first 2 MiB mapping from Xen image mapping
(suggested by Jan Beulich),
- improve commit message.
v7 - suggestions/fixes:
- minor cleanups
(suggested by Jan Beulich).
---
xen/arch/x86/Makefile | 2 +-
xen/arch/x86/Rules.mk | 3 +++
xen/arch/x86/boot/head.S | 8 --------
xen/arch/x86/boot/x86_64.S | 5 +++--
xen/arch/x86/setup.c | 3 ++-
xen/arch/x86/xen.lds.S | 2 +-
6 files changed, 10 insertions(+), 13 deletions(-)
diff --git a/xen/arch/x86/Makefile b/xen/arch/x86/Makefile
index 08e9f7b..e5b840e 100644
--- a/xen/arch/x86/Makefile
+++ b/xen/arch/x86/Makefile
@@ -90,7 +90,7 @@ all_symbols =
endif
$(TARGET): $(TARGET)-syms $(efi-y) boot/mkelf32
- ./boot/mkelf32 $(notes_phdrs) $(TARGET)-syms $(TARGET) 0x100000 \
+ ./boot/mkelf32 $(notes_phdrs) $(TARGET)-syms $(TARGET) $(XEN_IMG_OFFSET) \
`$(NM) $(TARGET)-syms | sed -ne 's/^\([^ ]*\) . __2M_rwdata_end$$/0x\1/p'`
ALL_OBJS := $(BASEDIR)/arch/x86/boot/built_in.o $(BASEDIR)/arch/x86/efi/built_in.o $(ALL_OBJS)
diff --git a/xen/arch/x86/Rules.mk b/xen/arch/x86/Rules.mk
index 72be8b2..568657e 100644
--- a/xen/arch/x86/Rules.mk
+++ b/xen/arch/x86/Rules.mk
@@ -1,9 +1,12 @@
########################################
# x86-specific definitions
+XEN_IMG_OFFSET := 0x200000
+
CFLAGS += -I$(BASEDIR)/include
CFLAGS += -I$(BASEDIR)/include/asm-x86/mach-generic
CFLAGS += -I$(BASEDIR)/include/asm-x86/mach-default
+CFLAGS += -DXEN_IMG_OFFSET=$(XEN_IMG_OFFSET)
CFLAGS += '-D__OBJECT_LABEL__=$(subst /,$$,$(subst -,_,$(subst $(BASEDIR)/,,$(CURDIR))/$@))'
# Prevent floating-point variables from creeping into Xen.
diff --git a/xen/arch/x86/boot/head.S b/xen/arch/x86/boot/head.S
index 2ecdcb3..acd47d5 100644
--- a/xen/arch/x86/boot/head.S
+++ b/xen/arch/x86/boot/head.S
@@ -509,14 +509,6 @@ trampoline_setup:
mov %eax,sym_phys(boot_tsc_stamp)
mov %edx,sym_phys(boot_tsc_stamp+4)
- /*
- * During boot, hook 4kB mappings of first 2MB of memory into L2.
- * This avoids mixing cachability for the legacy VGA region, and is
- * corrected when Xen relocates itself.
- */
- mov $sym_phys(l1_identmap)+__PAGE_HYPERVISOR,%edi
- mov %edi,sym_phys(l2_xenmap)
-
/* Apply relocations to bootstrap trampoline. */
mov sym_phys(trampoline_phys),%edx
mov $sym_phys(__trampoline_rel_start),%edi
diff --git a/xen/arch/x86/boot/x86_64.S b/xen/arch/x86/boot/x86_64.S
index 139b2ca..7890374 100644
--- a/xen/arch/x86/boot/x86_64.S
+++ b/xen/arch/x86/boot/x86_64.S
@@ -121,8 +121,9 @@ GLOBAL(l2_identmap)
* page.
*/
GLOBAL(l2_xenmap)
- idx = 0
- .rept 8
+ .quad 0
+ idx = 1
+ .rept 7
.quad sym_phys(__image_base__) + (idx << L2_PAGETABLE_SHIFT) + (PAGE_HYPERVISOR | _PAGE_PSE)
idx = idx + 1
.endr
diff --git a/xen/arch/x86/setup.c b/xen/arch/x86/setup.c
index d4b7d25..e6f6ef1 100644
--- a/xen/arch/x86/setup.c
+++ b/xen/arch/x86/setup.c
@@ -999,7 +999,8 @@ void __init noreturn __start_xen(unsigned long mbi_p)
* Undo the temporary-hooking of the l1_identmap. __2M_text_start
* is contained in this PTE.
*/
- BUG_ON(l2_table_offset((unsigned long)_erodata) ==
+ BUG_ON(using_2M_mapping() &&
+ l2_table_offset((unsigned long)_erodata) ==
l2_table_offset((unsigned long)_stext));
*pl2e++ = l2e_from_pfn(xen_phys_start >> PAGE_SHIFT,
PAGE_HYPERVISOR_RX | _PAGE_PSE);
diff --git a/xen/arch/x86/xen.lds.S b/xen/arch/x86/xen.lds.S
index addf2ef..632a387 100644
--- a/xen/arch/x86/xen.lds.S
+++ b/xen/arch/x86/xen.lds.S
@@ -55,7 +55,7 @@ SECTIONS
__2M_text_start = .; /* Start of 2M superpages, mapped RX. */
#endif
- . = __XEN_VIRT_START + MB(1);
+ . = __XEN_VIRT_START + XEN_IMG_OFFSET;
_start = .;
.text : {
_stext = .; /* Text and read-only data */
--
1.7.10.4
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply related [flat|nested] 15+ messages in thread* [PATCH v13 6/9] x86/setup: use XEN_IMG_OFFSET instead of...
2017-01-25 22:11 [PATCH v13 0/9] x86: multiboot2 protocol support Daniel Kiper
` (4 preceding siblings ...)
2017-01-25 22:11 ` [PATCH v13 5/9] x86: change default load address from 1 MiB to 2 MiB Daniel Kiper
@ 2017-01-25 22:11 ` Daniel Kiper
2017-01-25 22:11 ` [PATCH v13 7/9] x86: make Xen early boot code relocatable Daniel Kiper
` (2 subsequent siblings)
8 siblings, 0 replies; 15+ messages in thread
From: Daniel Kiper @ 2017-01-25 22:11 UTC (permalink / raw)
To: xen-devel
Cc: jgross, sstabellini, andrew.cooper3, cardoe, pgnet.dev, ning.sun,
julien.grall, jbeulich, qiaowei.ren, gang.wei, fu.wei
..calculating its value during runtime.
Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Doug Goldstein <cardoe@cardoe.com>
---
xen/arch/x86/setup.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/xen/arch/x86/setup.c b/xen/arch/x86/setup.c
index e6f6ef1..24b4b23 100644
--- a/xen/arch/x86/setup.c
+++ b/xen/arch/x86/setup.c
@@ -943,7 +943,6 @@ void __init noreturn __start_xen(unsigned long mbi_p)
l4_pgentry_t *pl4e;
l3_pgentry_t *pl3e;
l2_pgentry_t *pl2e;
- uint64_t load_start;
int i, j, k;
/* Select relocation address. */
@@ -957,9 +956,8 @@ void __init noreturn __start_xen(unsigned long mbi_p)
* with a barrier(). After this we must *not* modify static/global
* data until after we have switched to the relocated pagetables!
*/
- load_start = (unsigned long)_start - XEN_VIRT_START;
barrier();
- move_memory(e + load_start, load_start, _end - _start, 1);
+ move_memory(e + XEN_IMG_OFFSET, XEN_IMG_OFFSET, _end - _start, 1);
/* Walk initial pagetables, relocating page directory entries. */
pl4e = __va(__pa(idle_pg_table));
--
1.7.10.4
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply related [flat|nested] 15+ messages in thread* [PATCH v13 7/9] x86: make Xen early boot code relocatable
2017-01-25 22:11 [PATCH v13 0/9] x86: multiboot2 protocol support Daniel Kiper
` (5 preceding siblings ...)
2017-01-25 22:11 ` [PATCH v13 6/9] x86/setup: use XEN_IMG_OFFSET instead of Daniel Kiper
@ 2017-01-25 22:11 ` Daniel Kiper
2017-01-25 22:11 ` [PATCH v13 8/9] x86/boot: rename sym_phys() to sym_offs() Daniel Kiper
2017-01-25 22:11 ` [PATCH v13 9/9] x86: add multiboot2 protocol support for relocatable images Daniel Kiper
8 siblings, 0 replies; 15+ messages in thread
From: Daniel Kiper @ 2017-01-25 22:11 UTC (permalink / raw)
To: xen-devel
Cc: jgross, sstabellini, andrew.cooper3, cardoe, pgnet.dev, ning.sun,
julien.grall, jbeulich, qiaowei.ren, gang.wei, fu.wei
Every multiboot protocol (regardless of version) compatible image must
specify its load address (in ELF or multiboot header). Multiboot protocol
compatible loader have to load image at specified address. However, there
is no guarantee that the requested memory region (in case of Xen it starts
at 2 MiB and ends at ~5 MiB) where image should be loaded initially is a RAM
and it is free (legacy BIOS platforms are merciful for Xen but I found at
least one EFI platform on which Xen load address conflicts with EFI boot
services; it is Dell PowerEdge R820 with latest firmware). To cope with that
problem we must make Xen early boot code relocatable and help boot loader to
relocate image in proper way by suggesting, not requesting specific load
addresses as it is right now, allowed address ranges. This patch does former.
It does not add multiboot2 protocol interface which is done in "x86: add
multiboot2 protocol support for relocatable images" patch.
This patch changes following things:
- %esi register is used as a storage for Xen image load base address;
it is mostly unused in early boot code and preserved during C functions
calls in 32-bit mode,
- %fs is used as base for Xen data relative addressing in 32-bit code
if it is possible; %esi is used for that thing during error printing
because it is not always possible to properly and efficiently
initialize %fs.
Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
---
v13 - suggestions/fixes:
- move gdt_boot_descr to .init.data section
(suggested by Jan Beulich).
v12 - suggestions/fixes:
- store Xen image load base address directly into %esi,
- store Xen image load base address after x86_32_switch
(suggested by Doug Goldstein),
- improve commit message.
v8 - suggestions/fixes:
- use shld instead of mov and shr in BOOT_FS segment
descriptor base address initialization
(suggested by Jan Beulich),
- simplify code updating frame addresses in page tables
(suggested by Jan Beulich),
- print Xen image base addresses using "%#lx" format
(suggested by Jan Beulich),
- improve comments
(suggested by Jan Beulich).
v6 - suggestions/fixes:
- leave static mapping of first
16 MiB in l2_identmap as is
(suggested by Jan Beulich),
- use xen_phys_start instead of xen_img_load_base_addr
(suggested by Daniel Kiper and Jan Beulich),
- simplify BOOT_FS segment descriptor
base address initialization
(suggested by Jan Beulich),
- fix BOOT_FS segment limit
(suggested by Jan Beulich),
- do not rename sym_phys in this patch
(suggested by Jan Beulich),
- rename esi_offset/fs_offset to
sym_esi/sym_fs respectively
(suggested by Jan Beulich),
- use add instead of lea in assembly
error printing code
(suggested by Jan Beulich),
- improve comments
(suggested by Jan Beulich),
- improve commit message
(suggested by Jan Beulich),
- various minor cleanups and fixes
(suggested by Jan Beulich).
v4 - suggestions/fixes:
- do not relocate Xen image if boot loader did work for us
(suggested by Andrew Cooper and Jan Beulich),
- initialize xen_img_load_base_addr in EFI boot code too,
- properly initialize trampoline_xen_phys_start,
- calculate Xen image load base address in
x86_64 code ourselves,
(suggested by Jan Beulich),
- change how and when Xen image base address is printed,
- use %fs instead of %esi for relative addressing
(suggested by Andrew Cooper and Jan Beulich),
- create esi_offset and fs_offset() macros in assembly,
- calculate <final-exec-addr> mkelf32 argument automatically,
- optimize and cleanup code,
- improve comments,
- improve commit message.
v3 - suggestions/fixes:
- improve segment registers initialization
(suggested by Jan Beulich),
- simplify Xen image load base address calculation
(suggested by Jan Beulich),
- use %esi and %r15d instead of %ebp to store
Xen image load base address,
- use %esi instead of %fs for relative addressing;
this way we get shorter and simpler code,
- rename some variables and constants
(suggested by Jan Beulich),
- improve comments
(suggested by Konrad Rzeszutek Wilk),
- improve commit message
(suggested by Jan Beulich).
---
xen/arch/x86/boot/head.S | 168 ++++++++++++++++++++++++++++---------
xen/arch/x86/boot/trampoline.S | 5 ++
xen/arch/x86/boot/x86_64.S | 21 +++--
xen/arch/x86/setup.c | 14 ++--
xen/arch/x86/x86_64/asm-offsets.c | 3 +
xen/include/asm-x86/page.h | 2 +-
6 files changed, 157 insertions(+), 56 deletions(-)
diff --git a/xen/arch/x86/boot/head.S b/xen/arch/x86/boot/head.S
index acd47d5..c1414cf 100644
--- a/xen/arch/x86/boot/head.S
+++ b/xen/arch/x86/boot/head.S
@@ -13,12 +13,15 @@
.code32
#define sym_phys(sym) ((sym) - __XEN_VIRT_START)
+#define sym_esi(sym) sym_phys(sym)(%esi)
+#define sym_fs(sym) %fs:sym_phys(sym)
#define BOOT_CS32 0x0008
#define BOOT_CS64 0x0010
#define BOOT_DS 0x0018
#define BOOT_PSEUDORM_CS 0x0020
#define BOOT_PSEUDORM_DS 0x0028
+#define BOOT_FS 0x0030
#define MB2_HT(name) (MULTIBOOT2_HEADER_TAG_##name)
#define MB2_TT(name) (MULTIBOOT2_TAG_TYPE_##name)
@@ -101,13 +104,6 @@ multiboot2_header_start:
.Lmultiboot2_header_end:
.section .init.rodata, "a", @progbits
- .align 4
-
- .word 0
-gdt_boot_descr:
- .word 6*8-1
- .long sym_phys(trampoline_gdt)
- .long 0 /* Needed for 64-bit lgdt */
.Lbad_cpu_msg: .asciz "ERR: Not a 64-bit CPU!"
.Lbad_ldr_msg: .asciz "ERR: Not a Multiboot bootloader!"
@@ -119,6 +115,13 @@ gdt_boot_descr:
.section .init.data, "a", @progbits
.align 4
+ .word 0
+gdt_boot_descr:
+ .word 7*8-1
+gdt_boot_base:
+ .long sym_phys(trampoline_gdt)
+ .long 0 /* Needed for 64-bit lgdt */
+
vga_text_buffer:
.long 0xb8000
@@ -128,27 +131,27 @@ efi_platform:
.section .init.text, "ax", @progbits
bad_cpu:
- mov $(sym_phys(.Lbad_cpu_msg)),%esi # Error message
+ add $sym_phys(.Lbad_cpu_msg),%esi # Error message
jmp .Lget_vtb
not_multiboot:
- mov $(sym_phys(.Lbad_ldr_msg)),%esi # Error message
+ add $sym_phys(.Lbad_ldr_msg),%esi # Error message
jmp .Lget_vtb
.Lmb2_no_st:
- mov $(sym_phys(.Lbad_ldr_nst)),%esi # Error message
+ add $sym_phys(.Lbad_ldr_nst),%esi # Error message
jmp .Lget_vtb
.Lmb2_no_ih:
- mov $(sym_phys(.Lbad_ldr_nih)),%esi # Error message
+ add $sym_phys(.Lbad_ldr_nih),%esi # Error message
jmp .Lget_vtb
.Lmb2_no_bs:
- mov $(sym_phys(.Lbad_ldr_nbs)),%esi # Error message
+ add $sym_phys(.Lbad_ldr_nbs),%esi # Error message
xor %edi,%edi # No VGA text buffer
jmp .Lsend_chr
.Lmb2_efi_ia_32:
- mov $(sym_phys(.Lbad_efi_msg)),%esi # Error message
+ add $sym_phys(.Lbad_efi_msg),%esi # Error message
xor %edi,%edi # No VGA text buffer
jmp .Lsend_chr
.Lget_vtb:
- mov sym_phys(vga_text_buffer),%edi
+ mov sym_esi(vga_text_buffer),%edi
.Lsend_chr:
mov (%esi),%bl
test %bl,%bl # Terminate on '\0' sentinel
@@ -313,9 +316,13 @@ __efi64_mb2_start:
x86_32_switch:
mov %r15d,%edi
+ /* Store Xen image load base address in place accessible for 32-bit code. */
+ lea __image_base__(%rip),%esi
+
cli
/* Initialize GDTR. */
+ add %esi,gdt_boot_base(%rip)
lgdt gdt_boot_descr(%rip)
/* Reload code selector. */
@@ -351,12 +358,8 @@ __start:
cld
cli
- /* Initialise GDT and basic data segments. */
- lgdt %cs:sym_phys(gdt_boot_descr)
- mov $BOOT_DS,%ecx
- mov %ecx,%ds
- mov %ecx,%es
- mov %ecx,%ss
+ /* Load default Xen image load base address. */
+ mov $sym_phys(__image_base__),%esi
/* Bootloaders may set multiboot{1,2}.mem_lower to a nonzero value. */
xor %edx,%edx
@@ -413,6 +416,25 @@ __start:
jmp .Lmb2_tsize
trampoline_bios_setup:
+ /*
+ * Called on legacy BIOS platforms only.
+ *
+ * Initialize GDTR and basic data segments.
+ */
+ add %esi,sym_esi(gdt_boot_base)
+ lgdt sym_esi(gdt_boot_descr)
+
+ mov $BOOT_DS,%ecx
+ mov %ecx,%ds
+ mov %ecx,%es
+ mov %ecx,%ss
+ /* %esp is initialized later. */
+
+ /* Load null descriptor to unused segment registers. */
+ xor %ecx,%ecx
+ mov %ecx,%fs
+ mov %ecx,%gs
+
/* Set up trampoline segment 64k below EBDA */
movzwl 0x40e,%ecx /* EBDA segment */
cmp $0xa000,%ecx /* sanity check (high) */
@@ -440,19 +462,47 @@ trampoline_bios_setup:
xor %cl, %cl
trampoline_setup:
+ /*
+ * Called on legacy BIOS and EFI platforms.
+ *
+ * Initialize 0-15 bits of BOOT_FS segment descriptor base address.
+ */
+ mov %si,BOOT_FS+2+sym_esi(trampoline_gdt)
+
+ /* Initialize 16-23 bits of BOOT_FS segment descriptor base address. */
+ shld $16,%esi,%edx
+ mov %dl,BOOT_FS+4+sym_esi(trampoline_gdt)
+
+ /* Initialize 24-31 bits of BOOT_FS segment descriptor base address. */
+ mov %dh,BOOT_FS+7+sym_esi(trampoline_gdt)
+
+ /*
+ * Initialize %fs and later use it to access Xen data if possible.
+ * According to Intel 64 and IA-32 Architectures Software Developer's
+ * Manual it is safe to do that without reloading GDTR before.
+ */
+ mov $BOOT_FS,%edx
+ mov %edx,%fs
+
shl $4, %ecx
- mov %ecx,sym_phys(trampoline_phys)
+ mov %ecx,sym_fs(trampoline_phys)
+
+ /* Save Xen image load base address for later use. */
+ mov %esi,sym_fs(xen_phys_start)
+ mov %esi,sym_fs(trampoline_xen_phys_start)
+
+ /* Setup stack. %ss was initialized earlier. */
+ lea 1024+sym_esi(cpu0_stack),%esp
/* Get topmost low-memory stack address. */
add $TRAMPOLINE_SPACE,%ecx
/* Save the Multiboot info struct (after relocation) for later use. */
- mov $sym_phys(cpu0_stack)+1024,%esp
push %ecx /* Topmost low-memory stack address. */
push %ebx /* Multiboot information address. */
push %eax /* Multiboot magic. */
call reloc
- mov %eax,sym_phys(multiboot_ptr)
+ mov %eax,sym_fs(multiboot_ptr)
/*
* Now trampoline_phys points to the following structure (lowest
@@ -474,16 +524,20 @@ trampoline_setup:
* Do not zero BSS on EFI platform here.
* It was initialized earlier.
*/
- cmpb $0,sym_phys(efi_platform)
+ cmpb $0,sym_fs(efi_platform)
jnz 1f
/* Initialize BSS (no nasty surprises!). */
mov $sym_phys(__bss_start),%edi
mov $sym_phys(__bss_end),%ecx
+ push %fs
+ pop %es
sub %edi,%ecx
xor %eax,%eax
shr $2,%ecx
rep stosl
+ push %ds
+ pop %es
1:
/* Interrogate CPU extended features via CPUID. */
@@ -497,8 +551,8 @@ trampoline_setup:
jbe 1f
mov $0x80000001,%eax
cpuid
-1: mov %edx,sym_phys(cpuid_ext_features)
- mov %edx,sym_phys(boot_cpu_data)+CPUINFO_FEATURE_OFFSET(X86_FEATURE_LM)
+1: mov %edx,sym_fs(cpuid_ext_features)
+ mov %edx,sym_fs(boot_cpu_data)+CPUINFO_FEATURE_OFFSET(X86_FEATURE_LM)
/* Check for availability of long mode. */
bt $cpufeat_bit(X86_FEATURE_LM),%edx
@@ -506,15 +560,52 @@ trampoline_setup:
/* Stash TSC to calculate a good approximation of time-since-boot */
rdtsc
- mov %eax,sym_phys(boot_tsc_stamp)
- mov %edx,sym_phys(boot_tsc_stamp+4)
+ mov %eax,sym_fs(boot_tsc_stamp)
+ mov %edx,sym_fs(boot_tsc_stamp)+4
+
+ /*
+ * Update frame addresses in page tables excluding l2_identmap
+ * without its first entry which points to l1_identmap.
+ */
+ mov $((__page_tables_end-__page_tables_start)/8),%ecx
+ mov $(((l2_identmap-__page_tables_start)/8)+1),%edx
+1: cmp $((l2_identmap+l2_identmap_sizeof-__page_tables_start)/8),%ecx
+ cmove %edx,%ecx
+ testl $_PAGE_PRESENT,sym_fs(__page_tables_start)-8(,%ecx,8)
+ jz 2f
+ add %esi,sym_fs(__page_tables_start)-8(,%ecx,8)
+2: loop 1b
+
+ /* Initialize L2 boot-map/direct map page table entries (16MB). */
+ lea sym_esi(start),%ebx
+ lea (1<<L2_PAGETABLE_SHIFT)*7+(PAGE_HYPERVISOR|_PAGE_PSE)(%ebx),%eax
+ shr $(L2_PAGETABLE_SHIFT-3),%ebx
+ mov $8,%ecx
+1: mov %eax,sym_fs(l2_bootmap)-8(%ebx,%ecx,8)
+ mov %eax,sym_fs(l2_identmap)-8(%ebx,%ecx,8)
+ sub $(1<<L2_PAGETABLE_SHIFT),%eax
+ loop 1b
+
+ /* Initialize L3 boot-map page directory entry. */
+ lea __PAGE_HYPERVISOR+(L2_PAGETABLE_ENTRIES*8)*3+sym_esi(l2_bootmap),%eax
+ mov $4,%ecx
+1: mov %eax,sym_fs(l3_bootmap)-8(,%ecx,8)
+ sub $(L2_PAGETABLE_ENTRIES*8),%eax
+ loop 1b
+
+ /*
+ * During boot, hook 4kB mappings of first 2MB of memory into L2.
+ * This avoids mixing cachability for the legacy VGA region.
+ */
+ lea __PAGE_HYPERVISOR+sym_esi(l1_identmap),%edi
+ mov %edi,sym_fs(l2_bootmap)
/* Apply relocations to bootstrap trampoline. */
- mov sym_phys(trampoline_phys),%edx
+ mov sym_fs(trampoline_phys),%edx
mov $sym_phys(__trampoline_rel_start),%edi
1:
- mov (%edi),%eax
- add %edx,(%edi,%eax)
+ mov %fs:(%edi),%eax
+ add %edx,%fs:(%edi,%eax)
add $4,%edi
cmp $sym_phys(__trampoline_rel_stop),%edi
jb 1b
@@ -523,28 +614,29 @@ trampoline_setup:
shr $4,%edx
mov $sym_phys(__trampoline_seg_start),%edi
1:
- mov (%edi),%eax
- mov %dx,(%edi,%eax)
+ mov %fs:(%edi),%eax
+ mov %dx,%fs:(%edi,%eax)
add $4,%edi
cmp $sym_phys(__trampoline_seg_stop),%edi
jb 1b
/* Do not parse command line on EFI platform here. */
- cmpb $0,sym_phys(efi_platform)
+ cmpb $0,sym_fs(efi_platform)
jnz 1f
/* Bail if there is no command line to parse. */
- mov sym_phys(multiboot_ptr),%ebx
+ mov sym_fs(multiboot_ptr),%ebx
testl $MBI_CMDLINE,MB_flags(%ebx)
jz 1f
- pushl $sym_phys(early_boot_opts)
+ lea sym_esi(early_boot_opts),%eax
+ push %eax
pushl MB_cmdline(%ebx)
call cmdline_parse_early
1:
/* Switch to low-memory stack which lives at the end of trampoline region. */
- mov sym_phys(trampoline_phys),%edi
+ mov sym_fs(trampoline_phys),%edi
lea TRAMPOLINE_SPACE+TRAMPOLINE_STACK_SPACE(%edi),%esp
lea trampoline_boot_cpu_entry-trampoline_start(%edi),%eax
pushl $BOOT_CS32
@@ -553,7 +645,7 @@ trampoline_setup:
/* Copy bootstrap trampoline to low memory, below 1MB. */
mov $sym_phys(trampoline_start),%esi
mov $((trampoline_end - trampoline_start) / 4),%ecx
- rep movsl
+ rep movsl %fs:(%esi),%es:(%edi)
/* Jump into the relocated trampoline. */
lret
diff --git a/xen/arch/x86/boot/trampoline.S b/xen/arch/x86/boot/trampoline.S
index 2715d17..64f8efd 100644
--- a/xen/arch/x86/boot/trampoline.S
+++ b/xen/arch/x86/boot/trampoline.S
@@ -54,6 +54,11 @@ trampoline_gdt:
/* 0x0028: real-mode data @ BOOT_TRAMPOLINE */
.long 0x0000ffff
.long 0x00009200
+ /*
+ * 0x0030: ring 0 Xen data, 16 MiB size, base
+ * address is computed during runtime.
+ */
+ .quad 0x00c0920000000fff
.pushsection .trampoline_rel, "a"
.long trampoline_gdt + BOOT_PSEUDORM_CS + 2 - .
diff --git a/xen/arch/x86/boot/x86_64.S b/xen/arch/x86/boot/x86_64.S
index 7890374..7392004 100644
--- a/xen/arch/x86/boot/x86_64.S
+++ b/xen/arch/x86/boot/x86_64.S
@@ -81,7 +81,6 @@ GLOBAL(boot_cpu_compat_gdt_table)
.quad 0x0000910000000000 /* per-CPU entry (limit == cpu) */
.align PAGE_SIZE, 0
-GLOBAL(__page_tables_start)
/*
* Mapping of first 2 megabytes of memory. This is mapped with 4kB mappings
* to avoid type conflicts with fixed-range MTRRs covering the lowest megabyte
@@ -102,6 +101,13 @@ l1_identmap:
.size l1_identmap, . - l1_identmap
/*
+ * __page_tables_start does not cover l1_identmap because it (l1_identmap)
+ * contains 1-1 mappings. This means that frame addresses of these mappings
+ * are static and should not be updated during runtime.
+ */
+GLOBAL(__page_tables_start)
+
+/*
* Space for mapping the first 4GB of memory, with the first 16 megabytes
* actualy mapped (mostly using superpages). Uses 4x 4k pages.
*/
@@ -186,21 +192,14 @@ GLOBAL(idle_pg_table)
GLOBAL(__page_tables_end)
-/* Init pagetables. Enough page directories to map into the bottom 1GB. */
+/* Init pagetables. Enough page directories to map into 4GB. */
.section .init.data, "a", @progbits
.align PAGE_SIZE, 0
GLOBAL(l2_bootmap)
- .quad sym_phys(l1_identmap) + __PAGE_HYPERVISOR
- idx = 1
- .rept 7
- .quad (idx << L2_PAGETABLE_SHIFT) | __PAGE_HYPERVISOR | _PAGE_PSE
- idx = idx + 1
- .endr
- .fill L2_PAGETABLE_ENTRIES - 8, 8, 0
+ .fill 4 * L2_PAGETABLE_ENTRIES, 8, 0
.size l2_bootmap, . - l2_bootmap
GLOBAL(l3_bootmap)
- .quad sym_phys(l2_bootmap) + __PAGE_HYPERVISOR
- .fill L3_PAGETABLE_ENTRIES - 1, 8, 0
+ .fill L3_PAGETABLE_ENTRIES, 8, 0
.size l3_bootmap, . - l3_bootmap
diff --git a/xen/arch/x86/setup.c b/xen/arch/x86/setup.c
index 24b4b23..b75129a 100644
--- a/xen/arch/x86/setup.c
+++ b/xen/arch/x86/setup.c
@@ -330,9 +330,6 @@ static void *__init bootstrap_map(const module_t *mod)
if ( start >= end )
return NULL;
- if ( end <= BOOTSTRAP_MAP_BASE )
- return (void *)(unsigned long)start;
-
ret = (void *)(map_cur + (unsigned long)(start & mask));
start &= ~mask;
end = (end + mask) & ~mask;
@@ -716,6 +713,8 @@ void __init noreturn __start_xen(unsigned long mbi_p)
printk("Command line: %s\n", cmdline);
+ printk("Xen image load base address: %#lx\n", xen_phys_start);
+
printk("Video information:\n");
/* Print VGA display mode information. */
@@ -973,7 +972,7 @@ void __init noreturn __start_xen(unsigned long mbi_p)
/* Not present, 1GB mapping, or already relocated? */
if ( !(l3e_get_flags(*pl3e) & _PAGE_PRESENT) ||
(l3e_get_flags(*pl3e) & _PAGE_PSE) ||
- (l3e_get_pfn(*pl3e) > 0x1000) )
+ (l3e_get_pfn(*pl3e) > PFN_DOWN(xen_phys_start)) )
continue;
*pl3e = l3e_from_intpte(l3e_get_intpte(*pl3e) +
xen_phys_start);
@@ -983,7 +982,7 @@ void __init noreturn __start_xen(unsigned long mbi_p)
/* Not present, PSE, or already relocated? */
if ( !(l2e_get_flags(*pl2e) & _PAGE_PRESENT) ||
(l2e_get_flags(*pl2e) & _PAGE_PSE) ||
- (l2e_get_pfn(*pl2e) > 0x1000) )
+ (l2e_get_pfn(*pl2e) > PFN_DOWN(xen_phys_start)) )
continue;
*pl2e = l2e_from_intpte(l2e_get_intpte(*pl2e) +
xen_phys_start);
@@ -1006,7 +1005,8 @@ void __init noreturn __start_xen(unsigned long mbi_p)
{
unsigned int flags;
- if ( !(l2e_get_flags(*pl2e) & _PAGE_PRESENT) )
+ if ( !(l2e_get_flags(*pl2e) & _PAGE_PRESENT) ||
+ (l2e_get_pfn(*pl2e) > PFN_DOWN(xen_phys_start)) )
continue;
if ( !using_2M_mapping() )
@@ -1060,6 +1060,8 @@ void __init noreturn __start_xen(unsigned long mbi_p)
: "memory" );
bootstrap_map(NULL);
+
+ printk("New Xen image base address: %#lx\n", xen_phys_start);
}
/* Is the region suitable for relocating the multiboot modules? */
diff --git a/xen/arch/x86/x86_64/asm-offsets.c b/xen/arch/x86/x86_64/asm-offsets.c
index f135654..87e573a 100644
--- a/xen/arch/x86/x86_64/asm-offsets.c
+++ b/xen/arch/x86/x86_64/asm-offsets.c
@@ -179,5 +179,8 @@ void __dummy__(void)
OFFSET(MB2_efi64_ih, multiboot2_tag_efi64_ih_t, pointer);
BLANK();
+ DEFINE(l2_identmap_sizeof, sizeof(l2_identmap));
+ BLANK();
+
OFFSET(DOMAIN_vm_assist, struct domain, vm_assist);
}
diff --git a/xen/include/asm-x86/page.h b/xen/include/asm-x86/page.h
index af7d3e8..a54fdd1 100644
--- a/xen/include/asm-x86/page.h
+++ b/xen/include/asm-x86/page.h
@@ -288,7 +288,7 @@ extern root_pgentry_t idle_pg_table[ROOT_PAGETABLE_ENTRIES];
extern l2_pgentry_t *compat_idle_pg_table_l2;
extern unsigned int m2p_compat_vstart;
extern l2_pgentry_t l2_xenmap[L2_PAGETABLE_ENTRIES],
- l2_bootmap[L2_PAGETABLE_ENTRIES];
+ l2_bootmap[4*L2_PAGETABLE_ENTRIES];
extern l3_pgentry_t l3_bootmap[L3_PAGETABLE_ENTRIES];
extern l2_pgentry_t l2_identmap[4*L2_PAGETABLE_ENTRIES];
extern l1_pgentry_t l1_fixmap[L1_PAGETABLE_ENTRIES];
--
1.7.10.4
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply related [flat|nested] 15+ messages in thread* [PATCH v13 8/9] x86/boot: rename sym_phys() to sym_offs()
2017-01-25 22:11 [PATCH v13 0/9] x86: multiboot2 protocol support Daniel Kiper
` (6 preceding siblings ...)
2017-01-25 22:11 ` [PATCH v13 7/9] x86: make Xen early boot code relocatable Daniel Kiper
@ 2017-01-25 22:11 ` Daniel Kiper
2017-01-25 22:11 ` [PATCH v13 9/9] x86: add multiboot2 protocol support for relocatable images Daniel Kiper
8 siblings, 0 replies; 15+ messages in thread
From: Daniel Kiper @ 2017-01-25 22:11 UTC (permalink / raw)
To: xen-devel
Cc: jgross, sstabellini, andrew.cooper3, cardoe, pgnet.dev, ning.sun,
julien.grall, jbeulich, qiaowei.ren, gang.wei, fu.wei
This way macro name better describes its function.
Currently it is used to calculate symbol offset in
relation to the beginning of Xen image mapping.
However, value returned by sym_offs() for a given
symbol is not always equal its physical address.
There is no functional change.
Suggested-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Doug Goldstein <cardoe@cardoe.com>
---
v8 - suggestions/fixes:
- improve commit message
(suggested by Jan Beulich).
---
xen/arch/x86/boot/head.S | 38 +++++++++++++++++++-------------------
xen/arch/x86/boot/trampoline.S | 2 +-
xen/arch/x86/boot/wakeup.S | 4 ++--
xen/arch/x86/boot/x86_64.S | 18 +++++++++---------
4 files changed, 31 insertions(+), 31 deletions(-)
diff --git a/xen/arch/x86/boot/head.S b/xen/arch/x86/boot/head.S
index c1414cf..2d010fc 100644
--- a/xen/arch/x86/boot/head.S
+++ b/xen/arch/x86/boot/head.S
@@ -12,9 +12,9 @@
.text
.code32
-#define sym_phys(sym) ((sym) - __XEN_VIRT_START)
-#define sym_esi(sym) sym_phys(sym)(%esi)
-#define sym_fs(sym) %fs:sym_phys(sym)
+#define sym_offs(sym) ((sym) - __XEN_VIRT_START)
+#define sym_esi(sym) sym_offs(sym)(%esi)
+#define sym_fs(sym) %fs:sym_offs(sym)
#define BOOT_CS32 0x0008
#define BOOT_CS64 0x0010
@@ -97,7 +97,7 @@ multiboot2_header_start:
/* EFI64 Multiboot2 entry point. */
mb2ht_init MB2_HT(ENTRY_ADDRESS_EFI64), MB2_HT(OPTIONAL), \
- sym_phys(__efi64_mb2_start)
+ sym_offs(__efi64_mb2_start)
/* Multiboot2 header end tag. */
mb2ht_init MB2_HT(END), MB2_HT(REQUIRED)
@@ -119,7 +119,7 @@ multiboot2_header_start:
gdt_boot_descr:
.word 7*8-1
gdt_boot_base:
- .long sym_phys(trampoline_gdt)
+ .long sym_offs(trampoline_gdt)
.long 0 /* Needed for 64-bit lgdt */
vga_text_buffer:
@@ -131,23 +131,23 @@ efi_platform:
.section .init.text, "ax", @progbits
bad_cpu:
- add $sym_phys(.Lbad_cpu_msg),%esi # Error message
+ add $sym_offs(.Lbad_cpu_msg),%esi # Error message
jmp .Lget_vtb
not_multiboot:
- add $sym_phys(.Lbad_ldr_msg),%esi # Error message
+ add $sym_offs(.Lbad_ldr_msg),%esi # Error message
jmp .Lget_vtb
.Lmb2_no_st:
- add $sym_phys(.Lbad_ldr_nst),%esi # Error message
+ add $sym_offs(.Lbad_ldr_nst),%esi # Error message
jmp .Lget_vtb
.Lmb2_no_ih:
- add $sym_phys(.Lbad_ldr_nih),%esi # Error message
+ add $sym_offs(.Lbad_ldr_nih),%esi # Error message
jmp .Lget_vtb
.Lmb2_no_bs:
- add $sym_phys(.Lbad_ldr_nbs),%esi # Error message
+ add $sym_offs(.Lbad_ldr_nbs),%esi # Error message
xor %edi,%edi # No VGA text buffer
jmp .Lsend_chr
.Lmb2_efi_ia_32:
- add $sym_phys(.Lbad_efi_msg),%esi # Error message
+ add $sym_offs(.Lbad_efi_msg),%esi # Error message
xor %edi,%edi # No VGA text buffer
jmp .Lsend_chr
.Lget_vtb:
@@ -359,7 +359,7 @@ __start:
cli
/* Load default Xen image load base address. */
- mov $sym_phys(__image_base__),%esi
+ mov $sym_offs(__image_base__),%esi
/* Bootloaders may set multiboot{1,2}.mem_lower to a nonzero value. */
xor %edx,%edx
@@ -528,8 +528,8 @@ trampoline_setup:
jnz 1f
/* Initialize BSS (no nasty surprises!). */
- mov $sym_phys(__bss_start),%edi
- mov $sym_phys(__bss_end),%ecx
+ mov $sym_offs(__bss_start),%edi
+ mov $sym_offs(__bss_end),%ecx
push %fs
pop %es
sub %edi,%ecx
@@ -602,22 +602,22 @@ trampoline_setup:
/* Apply relocations to bootstrap trampoline. */
mov sym_fs(trampoline_phys),%edx
- mov $sym_phys(__trampoline_rel_start),%edi
+ mov $sym_offs(__trampoline_rel_start),%edi
1:
mov %fs:(%edi),%eax
add %edx,%fs:(%edi,%eax)
add $4,%edi
- cmp $sym_phys(__trampoline_rel_stop),%edi
+ cmp $sym_offs(__trampoline_rel_stop),%edi
jb 1b
/* Patch in the trampoline segment. */
shr $4,%edx
- mov $sym_phys(__trampoline_seg_start),%edi
+ mov $sym_offs(__trampoline_seg_start),%edi
1:
mov %fs:(%edi),%eax
mov %dx,%fs:(%edi,%eax)
add $4,%edi
- cmp $sym_phys(__trampoline_seg_stop),%edi
+ cmp $sym_offs(__trampoline_seg_stop),%edi
jb 1b
/* Do not parse command line on EFI platform here. */
@@ -643,7 +643,7 @@ trampoline_setup:
push %eax
/* Copy bootstrap trampoline to low memory, below 1MB. */
- mov $sym_phys(trampoline_start),%esi
+ mov $sym_offs(trampoline_start),%esi
mov $((trampoline_end - trampoline_start) / 4),%ecx
rep movsl %fs:(%esi),%es:(%edi)
diff --git a/xen/arch/x86/boot/trampoline.S b/xen/arch/x86/boot/trampoline.S
index 64f8efd..b96607a 100644
--- a/xen/arch/x86/boot/trampoline.S
+++ b/xen/arch/x86/boot/trampoline.S
@@ -92,7 +92,7 @@ trampoline_protmode_entry:
mov %ecx,%cr4
/* Load pagetable base register. */
- mov $sym_phys(idle_pg_table),%eax
+ mov $sym_offs(idle_pg_table),%eax
add bootsym_rel(trampoline_xen_phys_start,4,%eax)
mov %eax,%cr3
diff --git a/xen/arch/x86/boot/wakeup.S b/xen/arch/x86/boot/wakeup.S
index 08ea9b2..42d57ab 100644
--- a/xen/arch/x86/boot/wakeup.S
+++ b/xen/arch/x86/boot/wakeup.S
@@ -120,7 +120,7 @@ wakeup_32:
mov $bootsym_rel(wakeup_stack, 4, %esp)
# check saved magic again
- mov $sym_phys(saved_magic), %eax
+ mov $sym_offs(saved_magic),%eax
add bootsym_rel(trampoline_xen_phys_start, 4, %eax)
mov (%eax), %eax
cmp $0x9abcdef0, %eax
@@ -133,7 +133,7 @@ wakeup_32:
mov %ecx, %cr4
/* Load pagetable base register */
- mov $sym_phys(idle_pg_table),%eax
+ mov $sym_offs(idle_pg_table),%eax
add bootsym_rel(trampoline_xen_phys_start,4,%eax)
mov %eax,%cr3
diff --git a/xen/arch/x86/boot/x86_64.S b/xen/arch/x86/boot/x86_64.S
index 7392004..86d3775 100644
--- a/xen/arch/x86/boot/x86_64.S
+++ b/xen/arch/x86/boot/x86_64.S
@@ -112,7 +112,7 @@ GLOBAL(__page_tables_start)
* actualy mapped (mostly using superpages). Uses 4x 4k pages.
*/
GLOBAL(l2_identmap)
- .quad sym_phys(l1_identmap) + __PAGE_HYPERVISOR
+ .quad sym_offs(l1_identmap) + __PAGE_HYPERVISOR
idx = 1
.rept 7
.quad (idx << L2_PAGETABLE_SHIFT) | PAGE_HYPERVISOR | _PAGE_PSE
@@ -130,7 +130,7 @@ GLOBAL(l2_xenmap)
.quad 0
idx = 1
.rept 7
- .quad sym_phys(__image_base__) + (idx << L2_PAGETABLE_SHIFT) + (PAGE_HYPERVISOR | _PAGE_PSE)
+ .quad sym_offs(__image_base__) + (idx << L2_PAGETABLE_SHIFT) + (PAGE_HYPERVISOR | _PAGE_PSE)
idx = idx + 1
.endr
.fill L2_PAGETABLE_ENTRIES - 8, 8, 0
@@ -141,7 +141,7 @@ l2_fixmap:
idx = 0
.rept L2_PAGETABLE_ENTRIES
.if idx == l2_table_offset(FIXADDR_TOP - 1)
- .quad sym_phys(l1_fixmap) + __PAGE_HYPERVISOR
+ .quad sym_offs(l1_fixmap) + __PAGE_HYPERVISOR
.else
.quad 0
.endif
@@ -153,7 +153,7 @@ l2_fixmap:
l3_identmap:
idx = 0
.rept 4
- .quad sym_phys(l2_identmap) + (idx << PAGE_SHIFT) + __PAGE_HYPERVISOR
+ .quad sym_offs(l2_identmap) + (idx << PAGE_SHIFT) + __PAGE_HYPERVISOR
idx = idx + 1
.endr
.fill L3_PAGETABLE_ENTRIES - 4, 8, 0
@@ -164,9 +164,9 @@ l3_xenmap:
idx = 0
.rept L3_PAGETABLE_ENTRIES
.if idx == l3_table_offset(XEN_VIRT_START)
- .quad sym_phys(l2_xenmap) + __PAGE_HYPERVISOR
+ .quad sym_offs(l2_xenmap) + __PAGE_HYPERVISOR
.elseif idx == l3_table_offset(FIXADDR_TOP - 1)
- .quad sym_phys(l2_fixmap) + __PAGE_HYPERVISOR
+ .quad sym_offs(l2_fixmap) + __PAGE_HYPERVISOR
.else
.quad 0
.endif
@@ -176,13 +176,13 @@ l3_xenmap:
/* Top-level master (and idle-domain) page directory. */
GLOBAL(idle_pg_table)
- .quad sym_phys(l3_bootmap) + __PAGE_HYPERVISOR
+ .quad sym_offs(l3_bootmap) + __PAGE_HYPERVISOR
idx = 1
.rept L4_PAGETABLE_ENTRIES - 1
.if idx == l4_table_offset(DIRECTMAP_VIRT_START)
- .quad sym_phys(l3_identmap) + __PAGE_HYPERVISOR
+ .quad sym_offs(l3_identmap) + __PAGE_HYPERVISOR
.elseif idx == l4_table_offset(XEN_VIRT_START)
- .quad sym_phys(l3_xenmap) + __PAGE_HYPERVISOR
+ .quad sym_offs(l3_xenmap) + __PAGE_HYPERVISOR
.else
.quad 0
.endif
--
1.7.10.4
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply related [flat|nested] 15+ messages in thread* [PATCH v13 9/9] x86: add multiboot2 protocol support for relocatable images
2017-01-25 22:11 [PATCH v13 0/9] x86: multiboot2 protocol support Daniel Kiper
` (7 preceding siblings ...)
2017-01-25 22:11 ` [PATCH v13 8/9] x86/boot: rename sym_phys() to sym_offs() Daniel Kiper
@ 2017-01-25 22:11 ` Daniel Kiper
8 siblings, 0 replies; 15+ messages in thread
From: Daniel Kiper @ 2017-01-25 22:11 UTC (permalink / raw)
To: xen-devel
Cc: jgross, sstabellini, andrew.cooper3, cardoe, pgnet.dev, ning.sun,
julien.grall, jbeulich, qiaowei.ren, gang.wei, fu.wei
Add multiboot2 protocol support for relocatable images. Only GRUB2 with
"multiboot2: Add support for relocatable images" patch understands
that feature. Older multiboot protocol (regardless of version)
compatible loaders ignore it and everything works as usual.
Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Doug Goldstein <cardoe@cardoe.com>
---
v12 - suggestions/fixes:
- replace TABs with spaces in xen/include/xen/multiboot2.h
(suggested by Doug Goldstein).
v9 - suggestions/fixes:
- use .L labels instead of numeric ones in multiboot2 data scanning loop
(suggested by Jan Beulich).
v4 - suggestions/fixes:
- do not get Xen image load base address from
multiboot2 information in x86_64 code
(suggested by Jan Beulich),
- improve label names
(suggested by Jan Beulich),
- improve comments,
(suggested by Jan Beulich).
v3 - suggestions/fixes:
- use %esi and %r15d instead of %ebp to store
Xen image load base address,
- rename some types and constants,
- reformat xen/include/xen/multiboot2.h
(suggested by Konrad Rzeszutek Wilk),
- improve comments,
- improve commit message
(suggested by Konrad Rzeszutek Wilk).
---
xen/arch/x86/boot/head.S | 16 ++++++++++++++++
xen/arch/x86/x86_64/asm-offsets.c | 1 +
xen/include/xen/multiboot2.h | 13 +++++++++++++
3 files changed, 30 insertions(+)
diff --git a/xen/arch/x86/boot/head.S b/xen/arch/x86/boot/head.S
index 2d010fc..ab0a9d9 100644
--- a/xen/arch/x86/boot/head.S
+++ b/xen/arch/x86/boot/head.S
@@ -82,6 +82,13 @@ multiboot2_header_start:
/* Align modules at page boundry. */
mb2ht_init MB2_HT(MODULE_ALIGN), MB2_HT(REQUIRED)
+ /* Load address preference. */
+ mb2ht_init MB2_HT(RELOCATABLE), MB2_HT(OPTIONAL), \
+ sym_offs(start), /* Min load address. */ \
+ 0xffffffff, /* The end of image max load address (4 GiB - 1). */ \
+ 0x200000, /* Load address alignment (2 MiB). */ \
+ MULTIBOOT2_LOAD_PREFERENCE_HIGH
+
/* Console flags tag. */
mb2ht_init MB2_HT(CONSOLE_FLAGS), MB2_HT(OPTIONAL), \
MULTIBOOT2_CONSOLE_FLAGS_EGA_TEXT_SUPPORTED
@@ -391,6 +398,15 @@ __start:
cmp %edi,MB2_fixed_total_size(%ebx)
jbe trampoline_bios_setup
+ /* Get Xen image load base address from Multiboot2 information. */
+ cmpl $MULTIBOOT2_TAG_TYPE_LOAD_BASE_ADDR,MB2_tag_type(%ecx)
+ jne .Lmb2_mem_lower
+
+ mov MB2_load_base_addr(%ecx),%esi
+ sub $XEN_IMG_OFFSET,%esi
+ jmp .Lmb2_next_tag
+
+.Lmb2_mem_lower:
/* Get mem_lower from Multiboot2 information. */
cmpl $MULTIBOOT2_TAG_TYPE_BASIC_MEMINFO,MB2_tag_type(%ecx)
cmove MB2_mem_lower(%ecx),%edx
diff --git a/xen/arch/x86/x86_64/asm-offsets.c b/xen/arch/x86/x86_64/asm-offsets.c
index 87e573a..85639e4 100644
--- a/xen/arch/x86/x86_64/asm-offsets.c
+++ b/xen/arch/x86/x86_64/asm-offsets.c
@@ -174,6 +174,7 @@ void __dummy__(void)
OFFSET(MB2_fixed_total_size, multiboot2_fixed_t, total_size);
OFFSET(MB2_tag_type, multiboot2_tag_t, type);
OFFSET(MB2_tag_size, multiboot2_tag_t, size);
+ OFFSET(MB2_load_base_addr, multiboot2_tag_load_base_addr_t, load_base_addr);
OFFSET(MB2_mem_lower, multiboot2_tag_basic_meminfo_t, mem_lower);
OFFSET(MB2_efi64_st, multiboot2_tag_efi64_t, pointer);
OFFSET(MB2_efi64_ih, multiboot2_tag_efi64_ih_t, pointer);
diff --git a/xen/include/xen/multiboot2.h b/xen/include/xen/multiboot2.h
index a3e3119..5acd225 100644
--- a/xen/include/xen/multiboot2.h
+++ b/xen/include/xen/multiboot2.h
@@ -59,11 +59,17 @@
#define MULTIBOOT2_HEADER_TAG_EFI_BS 7
#define MULTIBOOT2_HEADER_TAG_ENTRY_ADDRESS_EFI32 8
#define MULTIBOOT2_HEADER_TAG_ENTRY_ADDRESS_EFI64 9
+#define MULTIBOOT2_HEADER_TAG_RELOCATABLE 10
/* Header tag flags. */
#define MULTIBOOT2_HEADER_TAG_REQUIRED 0
#define MULTIBOOT2_HEADER_TAG_OPTIONAL 1
+/* Where image should be loaded (suggestion not requirement). */
+#define MULTIBOOT2_LOAD_PREFERENCE_NONE 0
+#define MULTIBOOT2_LOAD_PREFERENCE_LOW 1
+#define MULTIBOOT2_LOAD_PREFERENCE_HIGH 2
+
/* Header console tag console_flags. */
#define MULTIBOOT2_CONSOLE_FLAGS_CONSOLE_REQUIRED 1
#define MULTIBOOT2_CONSOLE_FLAGS_EGA_TEXT_SUPPORTED 2
@@ -90,6 +96,7 @@
#define MULTIBOOT2_TAG_TYPE_EFI_BS 18
#define MULTIBOOT2_TAG_TYPE_EFI32_IH 19
#define MULTIBOOT2_TAG_TYPE_EFI64_IH 20
+#define MULTIBOOT2_TAG_TYPE_LOAD_BASE_ADDR 21
/* Multiboot 2 tag alignment. */
#define MULTIBOOT2_TAG_ALIGN 8
@@ -120,6 +127,12 @@ typedef struct {
typedef struct {
u32 type;
u32 size;
+ u32 load_base_addr;
+} multiboot2_tag_load_base_addr_t;
+
+typedef struct {
+ u32 type;
+ u32 size;
char string[];
} multiboot2_tag_string_t;
--
1.7.10.4
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply related [flat|nested] 15+ messages in thread