From 47226ad4f4cfd1e91ded7f2ec42f83ff1c624663 Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Wed, 3 Sep 2014 21:50:07 -0700 Subject: x86/efi: Only load initrd above 4g on second try MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Mantas found that after commit 4bf7111f5016 ("x86/efi: Support initrd loaded above 4G"), the kernel freezes at the earliest possible moment when trying to boot via UEFI on Asus laptop. Revert to old way to load initrd under 4G on first try, second try will use above 4G buffer when initrd is too big and does not fit under 4G. [ The cause of the freeze appears to be a firmware bug when reading file data into buffers above 4GB, though the exact reason is unknown. Mantas reports that the hang can be avoid if the file size is a multiple of 512 bytes, but I've seen some ASUS firmware simply corrupting the file data rather than freezing. Laszlo fixed an issue in the upstream EDK2 DiskIO code in Aug 2013 which may possibly be related, commit 4e39b75e ("MdeModulePkg/DiskIoDxe: fix source/destination pointer of overrun transfer"). Whatever the cause, it's unlikely that a fix will be forthcoming from the vendor, hence the workaround - Matt ] Cc: Laszlo Ersek Reported-by: Mantas Mikulėnas Reported-by: Harald Hoyer Tested-by: Anders Darander Tested-by: Calvin Walton Signed-off-by: Yinghai Lu Signed-off-by: Matt Fleming --- arch/x86/boot/compressed/eboot.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) (limited to 'arch/x86') diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c index f277184e2ac1..dca9842d8f91 100644 --- a/arch/x86/boot/compressed/eboot.c +++ b/arch/x86/boot/compressed/eboot.c @@ -1032,7 +1032,6 @@ struct boot_params *make_boot_params(struct efi_config *c) int i; unsigned long ramdisk_addr; unsigned long ramdisk_size; - unsigned long initrd_addr_max; efi_early = c; sys_table = (efi_system_table_t *)(unsigned long)efi_early->table; @@ -1095,15 +1094,20 @@ struct boot_params *make_boot_params(struct efi_config *c) memset(sdt, 0, sizeof(*sdt)); - if (hdr->xloadflags & XLF_CAN_BE_LOADED_ABOVE_4G) - initrd_addr_max = -1UL; - else - initrd_addr_max = hdr->initrd_addr_max; - status = handle_cmdline_files(sys_table, image, (char *)(unsigned long)hdr->cmd_line_ptr, - "initrd=", initrd_addr_max, + "initrd=", hdr->initrd_addr_max, &ramdisk_addr, &ramdisk_size); + + if (status != EFI_SUCCESS && + hdr->xloadflags & XLF_CAN_BE_LOADED_ABOVE_4G) { + efi_printk(sys_table, "Trying to load files to higher address\n"); + status = handle_cmdline_files(sys_table, image, + (char *)(unsigned long)hdr->cmd_line_ptr, + "initrd=", -1UL, + &ramdisk_addr, &ramdisk_size); + } + if (status != EFI_SUCCESS) goto fail2; hdr->ramdisk_image = ramdisk_addr & 0xffffffff; -- cgit v1.2.2 From 9cb0e394234d244fe5a97e743ec9dd7ddff7e64b Mon Sep 17 00:00:00 2001 From: Matt Fleming Date: Fri, 5 Sep 2014 14:52:26 +0100 Subject: x86/efi: Fixup GOT in all boot code paths Maarten reported that his Macbook pro 8.2 stopped booting after commit f23cf8bd5c1f49 ("efi/x86: efistub: Move shared dependencies to "), the main feature of which is changing the visibility of symbol 'efi_early' from local to global. By making 'efi_early' global we end up requiring an entry in the Global Offset Table. Unfortunately, while we do include code to fixup GOT entries in the early boot code, it's only called after we've executed the EFI boot stub. What this amounts to is that references to 'efi_early' in the EFI boot stub don't point to the correct place. Since we've got multiple boot entry points we need to be prepared to fixup the GOT in multiple places, while ensuring that we never do it more than once, otherwise the GOT entries will still point to the wrong place. Reported-by: Maarten Lankhorst Tested-by: Maarten Lankhorst Cc: Ard Biesheuvel Signed-off-by: Matt Fleming --- arch/x86/boot/compressed/head_32.S | 54 ++++++++++++++++++++++++++---------- arch/x86/boot/compressed/head_64.S | 56 ++++++++++++++++++++++++++++---------- 2 files changed, 81 insertions(+), 29 deletions(-) (limited to 'arch/x86') diff --git a/arch/x86/boot/compressed/head_32.S b/arch/x86/boot/compressed/head_32.S index cbed1407a5cd..d6b8aa4c986c 100644 --- a/arch/x86/boot/compressed/head_32.S +++ b/arch/x86/boot/compressed/head_32.S @@ -30,6 +30,33 @@ #include #include +/* + * Adjust our own GOT + * + * The relocation base must be in %ebx + * + * It is safe to call this macro more than once, because in some of the + * code paths multiple invocations are inevitable, e.g. via the efi* + * entry points. + * + * Relocation is only performed the first time. + */ +.macro FIXUP_GOT + cmpb $1, got_fixed(%ebx) + je 2f + + leal _got(%ebx), %edx + leal _egot(%ebx), %ecx +1: + cmpl %ecx, %edx + jae 2f + addl %ebx, (%edx) + addl $4, %edx + jmp 1b +2: + movb $1, got_fixed(%ebx) +.endm + __HEAD ENTRY(startup_32) #ifdef CONFIG_EFI_STUB @@ -56,6 +83,9 @@ ENTRY(efi_pe_entry) add %esi, 88(%eax) pushl %eax + movl %esi, %ebx + FIXUP_GOT + call make_boot_params cmpl $0, %eax je fail @@ -81,6 +111,10 @@ ENTRY(efi32_stub_entry) leal efi32_config(%esi), %eax add %esi, 88(%eax) pushl %eax + + movl %esi, %ebx + FIXUP_GOT + 2: call efi_main cmpl $0, %eax @@ -190,19 +224,7 @@ relocated: 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: - + FIXUP_GOT /* * Do the decompression, and jump to the new kernel.. */ @@ -225,8 +247,12 @@ relocated: xorl %ebx, %ebx jmp *%eax -#ifdef CONFIG_EFI_STUB .data +/* Have we relocated the GOT? */ +got_fixed: + .byte 0 + +#ifdef CONFIG_EFI_STUB efi32_config: .fill 11,8,0 .long efi_call_phys diff --git a/arch/x86/boot/compressed/head_64.S b/arch/x86/boot/compressed/head_64.S index 2884e0c3e8a5..50f69c7eaaf4 100644 --- a/arch/x86/boot/compressed/head_64.S +++ b/arch/x86/boot/compressed/head_64.S @@ -32,6 +32,33 @@ #include #include +/* + * Adjust our own GOT + * + * The relocation base must be in %rbx + * + * It is safe to call this macro more than once, because in some of the + * code paths multiple invocations are inevitable, e.g. via the efi* + * entry points. + * + * Relocation is only performed the first time. + */ +.macro FIXUP_GOT + cmpb $1, got_fixed(%rip) + je 2f + + leaq _got(%rip), %rdx + leaq _egot(%rip), %rcx +1: + cmpq %rcx, %rdx + jae 2f + addq %rbx, (%rdx) + addq $8, %rdx + jmp 1b +2: + movb $1, got_fixed(%rip) +.endm + __HEAD .code32 ENTRY(startup_32) @@ -252,10 +279,13 @@ ENTRY(efi_pe_entry) subq $1b, %rbp /* - * Relocate efi_config->call(). + * Relocate efi_config->call() and the GOT entries. */ addq %rbp, efi64_config+88(%rip) + movq %rbp, %rbx + FIXUP_GOT + movq %rax, %rdi call make_boot_params cmpq $0,%rax @@ -271,10 +301,13 @@ handover_entry: subq $1b, %rbp /* - * Relocate efi_config->call(). + * Relocate efi_config->call() and the GOT entries. */ movq efi_config(%rip), %rax addq %rbp, 88(%rax) + + movq %rbp, %rbx + FIXUP_GOT 2: movq efi_config(%rip), %rdi call efi_main @@ -385,19 +418,8 @@ relocated: shrq $3, %rcx rep stosq -/* - * Adjust our own GOT - */ - leaq _got(%rip), %rdx - leaq _egot(%rip), %rcx -1: - cmpq %rcx, %rdx - jae 2f - addq %rbx, (%rdx) - addq $8, %rdx - jmp 1b -2: - + FIXUP_GOT + /* * Do the decompression, and jump to the new kernel.. */ @@ -437,6 +459,10 @@ gdt: .quad 0x0000000000000000 /* TS continued */ gdt_end: +/* Have we relocated the GOT? */ +got_fixed: + .byte 0 + #ifdef CONFIG_EFI_STUB efi_config: .quad 0 -- cgit v1.2.2