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-rw-r--r--arch/x86/boot/boot.h18
-rw-r--r--arch/x86/boot/cmdline.c12
-rw-r--r--arch/x86/boot/compressed/cmdline.c12
-rw-r--r--arch/x86/boot/compressed/head_64.S48
-rw-r--r--arch/x86/boot/header.S10
5 files changed, 67 insertions, 33 deletions
diff --git a/arch/x86/boot/boot.h b/arch/x86/boot/boot.h
index 18997e5..5b75319 100644
--- a/arch/x86/boot/boot.h
+++ b/arch/x86/boot/boot.h
@@ -285,16 +285,26 @@ struct biosregs {
void intcall(u8 int_no, const struct biosregs *ireg, struct biosregs *oreg);
/* cmdline.c */
-int __cmdline_find_option(u32 cmdline_ptr, const char *option, char *buffer, int bufsize);
-int __cmdline_find_option_bool(u32 cmdline_ptr, const char *option);
+int __cmdline_find_option(unsigned long cmdline_ptr, const char *option, char *buffer, int bufsize);
+int __cmdline_find_option_bool(unsigned long cmdline_ptr, const char *option);
static inline int cmdline_find_option(const char *option, char *buffer, int bufsize)
{
- return __cmdline_find_option(boot_params.hdr.cmd_line_ptr, option, buffer, bufsize);
+ unsigned long cmd_line_ptr = boot_params.hdr.cmd_line_ptr;
+
+ if (cmd_line_ptr >= 0x100000)
+ return -1; /* inaccessible */
+
+ return __cmdline_find_option(cmd_line_ptr, option, buffer, bufsize);
}
static inline int cmdline_find_option_bool(const char *option)
{
- return __cmdline_find_option_bool(boot_params.hdr.cmd_line_ptr, option);
+ unsigned long cmd_line_ptr = boot_params.hdr.cmd_line_ptr;
+
+ if (cmd_line_ptr >= 0x100000)
+ return -1; /* inaccessible */
+
+ return __cmdline_find_option_bool(cmd_line_ptr, option);
}
diff --git a/arch/x86/boot/cmdline.c b/arch/x86/boot/cmdline.c
index 6b3b6f7..625d21b 100644
--- a/arch/x86/boot/cmdline.c
+++ b/arch/x86/boot/cmdline.c
@@ -27,7 +27,7 @@ static inline int myisspace(u8 c)
* Returns the length of the argument (regardless of if it was
* truncated to fit in the buffer), or -1 on not found.
*/
-int __cmdline_find_option(u32 cmdline_ptr, const char *option, char *buffer, int bufsize)
+int __cmdline_find_option(unsigned long cmdline_ptr, const char *option, char *buffer, int bufsize)
{
addr_t cptr;
char c;
@@ -41,8 +41,8 @@ int __cmdline_find_option(u32 cmdline_ptr, const char *option, char *buffer, int
st_bufcpy /* Copying this to buffer */
} state = st_wordstart;
- if (!cmdline_ptr || cmdline_ptr >= 0x100000)
- return -1; /* No command line, or inaccessible */
+ if (!cmdline_ptr)
+ return -1; /* No command line */
cptr = cmdline_ptr & 0xf;
set_fs(cmdline_ptr >> 4);
@@ -99,7 +99,7 @@ int __cmdline_find_option(u32 cmdline_ptr, const char *option, char *buffer, int
* Returns the position of that option (starts counting with 1)
* or 0 on not found
*/
-int __cmdline_find_option_bool(u32 cmdline_ptr, const char *option)
+int __cmdline_find_option_bool(unsigned long cmdline_ptr, const char *option)
{
addr_t cptr;
char c;
@@ -111,8 +111,8 @@ int __cmdline_find_option_bool(u32 cmdline_ptr, const char *option)
st_wordskip, /* Miscompare, skip */
} state = st_wordstart;
- if (!cmdline_ptr || cmdline_ptr >= 0x100000)
- return -1; /* No command line, or inaccessible */
+ if (!cmdline_ptr)
+ return -1; /* No command line */
cptr = cmdline_ptr & 0xf;
set_fs(cmdline_ptr >> 4);
diff --git a/arch/x86/boot/compressed/cmdline.c b/arch/x86/boot/compressed/cmdline.c
index 10f6b11..bffd73b 100644
--- a/arch/x86/boot/compressed/cmdline.c
+++ b/arch/x86/boot/compressed/cmdline.c
@@ -13,13 +13,21 @@ static inline char rdfs8(addr_t addr)
return *((char *)(fs + addr));
}
#include "../cmdline.c"
+static unsigned long get_cmd_line_ptr(void)
+{
+ unsigned long cmd_line_ptr = real_mode->hdr.cmd_line_ptr;
+
+ cmd_line_ptr |= (u64)real_mode->ext_cmd_line_ptr << 32;
+
+ return cmd_line_ptr;
+}
int cmdline_find_option(const char *option, char *buffer, int bufsize)
{
- return __cmdline_find_option(real_mode->hdr.cmd_line_ptr, option, buffer, bufsize);
+ return __cmdline_find_option(get_cmd_line_ptr(), option, buffer, bufsize);
}
int cmdline_find_option_bool(const char *option)
{
- return __cmdline_find_option_bool(real_mode->hdr.cmd_line_ptr, option);
+ return __cmdline_find_option_bool(get_cmd_line_ptr(), option);
}
#endif
diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S
index f5d1aaa..c1d383d 100644
--- a/arch/x86/boot/compressed/head_64.S
+++ b/arch/x86/boot/compressed/head_64.S
@@ -37,6 +37,12 @@
__HEAD
.code32
ENTRY(startup_32)
+ /*
+ * 32bit entry is 0 and it is ABI so immutable!
+ * If we come here directly from a bootloader,
+ * kernel(text+data+bss+brk) ramdisk, zero_page, command line
+ * all need to be under the 4G limit.
+ */
cld
/*
* Test KEEP_SEGMENTS flag to see if the bootloader is asking
@@ -154,6 +160,12 @@ ENTRY(startup_32)
btsl $_EFER_LME, %eax
wrmsr
+ /* After gdt is loaded */
+ xorl %eax, %eax
+ lldt %ax
+ movl $0x20, %eax
+ ltr %ax
+
/*
* Setup for the jump to 64bit mode
*
@@ -176,28 +188,18 @@ ENTRY(startup_32)
lret
ENDPROC(startup_32)
-no_longmode:
- /* This isn't an x86-64 CPU so hang */
-1:
- hlt
- jmp 1b
-
-#include "../../kernel/verify_cpu.S"
-
- /*
- * Be careful here startup_64 needs to be at a predictable
- * address so I can export it in an ELF header. Bootloaders
- * should look at the ELF header to find this address, as
- * it may change in the future.
- */
.code64
.org 0x200
ENTRY(startup_64)
/*
+ * 64bit entry is 0x200 and it is ABI so immutable!
* We come here either from startup_32 or directly from a
- * 64bit bootloader. If we come here from a bootloader we depend on
- * an identity mapped page table being provied that maps our
- * entire text+data+bss and hopefully all of memory.
+ * 64bit bootloader.
+ * If we come here from a bootloader, kernel(text+data+bss+brk),
+ * ramdisk, zero_page, command line could be above 4G.
+ * We depend on an identity mapped page table being provided
+ * that maps our entire kernel(text+data+bss+brk), zero page
+ * and command line.
*/
#ifdef CONFIG_EFI_STUB
/*
@@ -247,9 +249,6 @@ preferred_addr:
movl %eax, %ss
movl %eax, %fs
movl %eax, %gs
- lldt %ax
- movl $0x20, %eax
- ltr %ax
/*
* Compute the decompressed kernel start address. It is where
@@ -349,6 +348,15 @@ relocated:
*/
jmp *%rbp
+ .code32
+no_longmode:
+ /* This isn't an x86-64 CPU so hang */
+1:
+ hlt
+ jmp 1b
+
+#include "../../kernel/verify_cpu.S"
+
.data
gdt:
.word gdt_end - gdt
diff --git a/arch/x86/boot/header.S b/arch/x86/boot/header.S
index 944ce59..9ec06a1 100644
--- a/arch/x86/boot/header.S
+++ b/arch/x86/boot/header.S
@@ -374,6 +374,14 @@ xloadflags:
#else
# define XLF0 0
#endif
+
+#if defined(CONFIG_RELOCATABLE) && defined(CONFIG_X86_64)
+ /* kernel/boot_param/ramdisk could be loaded above 4g */
+# define XLF1 XLF_CAN_BE_LOADED_ABOVE_4G
+#else
+# define XLF1 0
+#endif
+
#ifdef CONFIG_EFI_STUB
# ifdef CONFIG_X86_64
# define XLF23 XLF_EFI_HANDOVER_64 /* 64-bit EFI handover ok */
@@ -383,7 +391,7 @@ xloadflags:
#else
# define XLF23 0
#endif
- .word XLF0 | XLF23
+ .word XLF0 | XLF1 | XLF23
cmdline_size: .long COMMAND_LINE_SIZE-1 #length of the command line,
#added with boot protocol
generated by cgit v0.10.2 at 2024-06-29 04:57:05 (GMT)