From 9d77db3c730780c8ef5ccd4b66403ff5675cfe4e Mon Sep 17 00:00:00 2001 From: hc <hc@nodka.com> Date: Mon, 13 May 2024 10:30:14 +0000 Subject: [PATCH] modify sin led gpio --- kernel/arch/x86/boot/compressed/head_32.S | 236 ++++++++++++++++++++++------------------------------------ 1 files changed, 89 insertions(+), 147 deletions(-) diff --git a/kernel/arch/x86/boot/compressed/head_32.S b/kernel/arch/x86/boot/compressed/head_32.S index c6c4b87..659fad5 100644 --- a/kernel/arch/x86/boot/compressed/head_32.S +++ b/kernel/arch/x86/boot/compressed/head_32.S @@ -33,52 +33,19 @@ #include <asm/bootparam.h> /* - * The 32-bit x86 assembler in binutils 2.26 will generate R_386_GOT32X - * relocation to get the symbol address in PIC. When the compressed x86 - * kernel isn't built as PIC, the linker optimizes R_386_GOT32X - * relocations to their fixed symbol addresses. However, when the - * compressed x86 kernel is loaded at a different address, it leads - * to the following load failure: - * - * Failed to allocate space for phdrs - * - * during the decompression stage. - * - * If the compressed x86 kernel is relocatable at run-time, it should be - * compiled with -fPIE, instead of -fPIC, if possible and should be built as - * Position Independent Executable (PIE) so that linker won't optimize - * R_386_GOT32X relocation to its fixed symbol address. Older - * linkers generate R_386_32 relocations against locally defined symbols, - * _bss, _ebss, _got, _egot and _end, in PIE. It isn't wrong, just less - * optimal than R_386_RELATIVE. But the x86 kernel fails to properly handle - * R_386_32 relocations when relocating the kernel. To generate - * R_386_RELATIVE relocations, we mark _bss, _ebss, _got, _egot and _end as - * hidden: + * These symbols needed to be marked as .hidden to prevent the BFD linker from + * generating R_386_32 (rather than R_386_RELATIVE) relocations for them when + * the 32-bit compressed kernel is linked as PIE. This is no longer necessary, + * but it doesn't hurt to keep them .hidden. */ .hidden _bss .hidden _ebss - .hidden _got - .hidden _egot .hidden _end __HEAD -ENTRY(startup_32) +SYM_FUNC_START(startup_32) cld - /* - * Test KEEP_SEGMENTS flag to see if the bootloader is asking - * us to not reload segments - */ - testb $KEEP_SEGMENTS, BP_loadflags(%esi) - jnz 1f - cli - movl $__BOOT_DS, %eax - movl %eax, %ds - movl %eax, %es - movl %eax, %fs - movl %eax, %gs - movl %eax, %ss -1: /* * Calculate the delta between where we were compiled to run @@ -90,17 +57,46 @@ */ leal (BP_scratch+4)(%esi), %esp call 1f -1: popl %ebp - subl $1b, %ebp +1: popl %edx + addl $_GLOBAL_OFFSET_TABLE_+(.-1b), %edx + + /* Load new GDT */ + leal gdt@GOTOFF(%edx), %eax + movl %eax, 2(%eax) + lgdt (%eax) + + /* Load segment registers with our descriptors */ + movl $__BOOT_DS, %eax + movl %eax, %ds + movl %eax, %es + movl %eax, %fs + movl %eax, %gs + movl %eax, %ss /* - * %ebp contains the address we are loaded at by the boot loader and %ebx - * contains the address where we should move the kernel image temporarily - * for safe in-place decompression. + * %edx contains the address we are loaded at by the boot loader (plus the + * offset to the GOT). The below code calculates %ebx to be the address where + * we should move the kernel image temporarily for safe in-place decompression + * (again, plus the offset to the GOT). + * + * %ebp is calculated to be the address that the kernel will be decompressed to. */ #ifdef CONFIG_RELOCATABLE - movl %ebp, %ebx + leal startup_32@GOTOFF(%edx), %ebx + +#ifdef CONFIG_EFI_STUB +/* + * If we were loaded via the EFI LoadImage service, startup_32() will be at an + * offset to the start of the space allocated for the image. efi_pe_entry() will + * set up image_offset to tell us where the image actually starts, so that we + * can use the full available buffer. + * image_offset = startup_32 - image_base + * Otherwise image_offset will be zero and has no effect on the calculations. + */ + subl image_offset@GOTOFF(%edx), %ebx +#endif + movl BP_kernel_alignment(%esi), %eax decl %eax addl %eax, %ebx @@ -112,13 +108,13 @@ movl $LOAD_PHYSICAL_ADDR, %ebx 1: + movl %ebx, %ebp // Save the output address for later /* Target address to relocate to for decompression */ - movl BP_init_size(%esi), %eax - subl $_end, %eax - addl %eax, %ebx + addl BP_init_size(%esi), %ebx + subl $_end@GOTOFF, %ebx /* Set up the stack */ - leal boot_stack_end(%ebx), %esp + leal boot_stack_end@GOTOFF(%ebx), %esp /* Zero EFLAGS */ pushl $0 @@ -129,8 +125,8 @@ * where decompression in place becomes safe. */ pushl %esi - leal (_bss-4)(%ebp), %esi - leal (_bss-4)(%ebx), %edi + leal (_bss@GOTOFF-4)(%edx), %esi + leal (_bss@GOTOFF-4)(%ebx), %edi movl $(_bss - startup_32), %ecx shrl $2, %ecx std @@ -138,122 +134,61 @@ cld popl %esi + /* + * The GDT may get overwritten either during the copy we just did or + * during extract_kernel below. To avoid any issues, repoint the GDTR + * to the new copy of the GDT. + */ + leal gdt@GOTOFF(%ebx), %eax + movl %eax, 2(%eax) + lgdt (%eax) + /* * Jump to the relocated address. */ - leal relocated(%ebx), %eax + leal .Lrelocated@GOTOFF(%ebx), %eax jmp *%eax -ENDPROC(startup_32) +SYM_FUNC_END(startup_32) #ifdef CONFIG_EFI_STUB -/* - * We don't need the return address, so set up the stack so efi_main() can find - * its arguments. - */ -ENTRY(efi_pe_entry) +SYM_FUNC_START(efi32_stub_entry) +SYM_FUNC_START_ALIAS(efi_stub_entry) add $0x4, %esp - - call 1f -1: popl %esi - subl $1b, %esi - - popl %ecx - movl %ecx, efi32_config(%esi) /* Handle */ - popl %ecx - movl %ecx, efi32_config+8(%esi) /* EFI System table pointer */ - - /* Relocate efi_config->call() */ - leal efi32_config(%esi), %eax - add %esi, 40(%eax) - pushl %eax - - call make_boot_params - cmpl $0, %eax - je fail - movl %esi, BP_code32_start(%eax) - popl %ecx - pushl %eax - pushl %ecx - jmp 2f /* Skip efi_config initialization */ -ENDPROC(efi_pe_entry) - -ENTRY(efi32_stub_entry) - add $0x4, %esp - popl %ecx - popl %edx - - call 1f -1: popl %esi - subl $1b, %esi - - movl %ecx, efi32_config(%esi) /* Handle */ - movl %edx, efi32_config+8(%esi) /* EFI System table pointer */ - - /* Relocate efi_config->call() */ - leal efi32_config(%esi), %eax - add %esi, 40(%eax) - pushl %eax -2: + movl 8(%esp), %esi /* save boot_params pointer */ call efi_main - cmpl $0, %eax - movl %eax, %esi - jne 2f -fail: - /* EFI init failed, so hang. */ - hlt - jmp fail -2: - movl BP_code32_start(%esi), %eax - leal startup_32(%eax), %eax + /* efi_main returns the possibly relocated address of startup_32 */ jmp *%eax -ENDPROC(efi32_stub_entry) +SYM_FUNC_END(efi32_stub_entry) +SYM_FUNC_END_ALIAS(efi_stub_entry) #endif .text -relocated: +SYM_FUNC_START_LOCAL_NOALIGN(.Lrelocated) /* * Clear BSS (stack is currently empty) */ xorl %eax, %eax - leal _bss(%ebx), %edi - leal _ebss(%ebx), %ecx + leal _bss@GOTOFF(%ebx), %edi + leal _ebss@GOTOFF(%ebx), %ecx subl %edi, %ecx shrl $2, %ecx rep stosl /* - * Adjust our own GOT - */ - leal _got(%ebx), %edx - leal _egot(%ebx), %ecx -1: - cmpl %ecx, %edx - jae 2f - addl %ebx, (%edx) - addl $4, %edx - jmp 1b -2: - -/* * Do the extraction, and jump to the new kernel.. */ - /* push arguments for extract_kernel: */ - pushl $z_output_len /* decompressed length, end of relocs */ + /* push arguments for extract_kernel: */ - movl BP_init_size(%esi), %eax - subl $_end, %eax - movl %ebx, %ebp - subl %eax, %ebp - pushl %ebp /* output address */ - - pushl $z_input_len /* input_len */ - leal input_data(%ebx), %eax - pushl %eax /* input_data */ - leal boot_heap(%ebx), %eax - pushl %eax /* heap area */ - pushl %esi /* real mode pointer */ - call extract_kernel /* returns kernel location in %eax */ + pushl output_len@GOTOFF(%ebx) /* decompressed length, end of relocs */ + pushl %ebp /* output address */ + pushl input_len@GOTOFF(%ebx) /* input_len */ + leal input_data@GOTOFF(%ebx), %eax + pushl %eax /* input_data */ + leal boot_heap@GOTOFF(%ebx), %eax + pushl %eax /* heap area */ + pushl %esi /* real mode pointer */ + call extract_kernel /* returns kernel location in %eax */ addl $24, %esp /* @@ -261,14 +196,21 @@ */ xorl %ebx, %ebx jmp *%eax +SYM_FUNC_END(.Lrelocated) + + .data + .balign 8 +SYM_DATA_START_LOCAL(gdt) + .word gdt_end - gdt - 1 + .long 0 + .word 0 + .quad 0x0000000000000000 /* Reserved */ + .quad 0x00cf9a000000ffff /* __KERNEL_CS */ + .quad 0x00cf92000000ffff /* __KERNEL_DS */ +SYM_DATA_END_LABEL(gdt, SYM_L_LOCAL, gdt_end) #ifdef CONFIG_EFI_STUB - .data -efi32_config: - .fill 5,8,0 - .long efi_call_phys - .long 0 - .byte 0 +SYM_DATA(image_offset, .long 0) #endif /* -- Gitblit v1.6.2