| From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 |
| From: Peter Jones <pjones@redhat.com> |
| Date: Tue, 14 Feb 2017 16:18:54 -0500 |
| Subject: [PATCH] Handle multi-arch (64-on-32) boot in linuxefi loader. |
| |
| Allow booting 64-bit kernels on 32-bit EFI on x86. |
| |
| Signed-off-by: Peter Jones <pjones@redhat.com> |
| |
| grub-core/loader/efi/linux.c | 9 +++- |
| grub-core/loader/i386/efi/linux.c | 110 ++++++++++++++++++++++++++------------ |
| include/grub/i386/linux.h | 7 ++- |
| 3 files changed, 89 insertions(+), 37 deletions(-) |
| |
| diff --git a/grub-core/loader/efi/linux.c b/grub-core/loader/efi/linux.c |
| index c8ecce6dfd0..0622dfa48d4 100644 |
| |
| |
| @@ -69,12 +69,17 @@ grub_linuxefi_secure_validate (void *data, grub_uint32_t size) |
| typedef void (*handover_func) (void *, grub_efi_system_table_t *, void *); |
| |
| grub_err_t |
| -grub_efi_linux_boot (void *kernel_addr, grub_off_t offset, |
| +grub_efi_linux_boot (void *kernel_addr, grub_off_t handover_offset, |
| void *kernel_params) |
| { |
| handover_func hf; |
| + int offset = 0; |
| |
| - hf = (handover_func)((char *)kernel_addr + offset); |
| +#ifdef __x86_64__ |
| + offset = 512; |
| +#endif |
| + |
| + hf = (handover_func)((char *)kernel_addr + handover_offset + offset); |
| hf (grub_efi_image_handle, grub_efi_system_table, kernel_params); |
| |
| return GRUB_ERR_BUG; |
| diff --git a/grub-core/loader/i386/efi/linux.c b/grub-core/loader/i386/efi/linux.c |
| index 8db228c5bf5..800c3e54022 100644 |
| |
| |
| @@ -44,14 +44,10 @@ static char *linux_cmdline; |
| static grub_err_t |
| grub_linuxefi_boot (void) |
| { |
| - int offset = 0; |
| - |
| -#ifdef __x86_64__ |
| - offset = 512; |
| -#endif |
| asm volatile ("cli"); |
| |
| - return grub_efi_linux_boot ((char *)kernel_mem, handover_offset + offset, |
| + return grub_efi_linux_boot ((char *)kernel_mem, |
| + handover_offset, |
| params); |
| } |
| |
| @@ -154,14 +150,20 @@ grub_cmd_initrd (grub_command_t cmd __attribute__ ((unused)), |
| return grub_errno; |
| } |
| |
| +#define MIN(a, b) \ |
| + ({ typeof (a) _a = (a); \ |
| + typeof (b) _b = (b); \ |
| + _a < _b ? _a : _b; }) |
| + |
| static grub_err_t |
| grub_cmd_linux (grub_command_t cmd __attribute__ ((unused)), |
| int argc, char *argv[]) |
| { |
| grub_file_t file = 0; |
| - struct linux_kernel_header lh; |
| - grub_ssize_t len, start, filelen; |
| + struct linux_i386_kernel_header *lh = NULL; |
| + grub_ssize_t start, filelen; |
| void *kernel = NULL; |
| + int setup_header_end_offset; |
| int rc; |
| |
| grub_dl_ref (my_mod); |
| @@ -201,48 +203,79 @@ grub_cmd_linux (grub_command_t cmd __attribute__ ((unused)), |
| goto fail; |
| } |
| |
| - params = grub_efi_allocate_pages_max (0x3fffffff, BYTES_TO_PAGES(16384)); |
| - |
| + params = grub_efi_allocate_pages_max (0x3fffffff, |
| + BYTES_TO_PAGES(sizeof(*params))); |
| if (! params) |
| { |
| grub_error (GRUB_ERR_OUT_OF_MEMORY, "cannot allocate kernel parameters"); |
| goto fail; |
| } |
| |
| - grub_dprintf ("linux", "params = %lx\n", (unsigned long) params); |
| + grub_dprintf ("linux", "params = %p\n", params); |
| |
| - grub_memset (params, 0, 16384); |
| + grub_memset (params, 0, sizeof(*params)); |
| |
| - grub_memcpy (&lh, kernel, sizeof (lh)); |
| - |
| - if (lh.boot_flag != grub_cpu_to_le16 (0xaa55)) |
| + setup_header_end_offset = *((grub_uint8_t *)kernel + 0x201); |
| + grub_dprintf ("linux", "copying %lu bytes from %p to %p\n", |
| + MIN((grub_size_t)0x202+setup_header_end_offset, |
| + sizeof (*params)) - 0x1f1, |
| + (grub_uint8_t *)kernel + 0x1f1, |
| + (grub_uint8_t *)params + 0x1f1); |
| + grub_memcpy ((grub_uint8_t *)params + 0x1f1, |
| + (grub_uint8_t *)kernel + 0x1f1, |
| + MIN((grub_size_t)0x202+setup_header_end_offset,sizeof (*params)) - 0x1f1); |
| + lh = (struct linux_i386_kernel_header *)params; |
| + grub_dprintf ("linux", "lh is at %p\n", lh); |
| + grub_dprintf ("linux", "checking lh->boot_flag\n"); |
| + if (lh->boot_flag != grub_cpu_to_le16 (0xaa55)) |
| { |
| grub_error (GRUB_ERR_BAD_OS, N_("invalid magic number")); |
| goto fail; |
| } |
| |
| - if (lh.setup_sects > GRUB_LINUX_MAX_SETUP_SECTS) |
| + grub_dprintf ("linux", "checking lh->setup_sects\n"); |
| + if (lh->setup_sects > GRUB_LINUX_MAX_SETUP_SECTS) |
| { |
| grub_error (GRUB_ERR_BAD_OS, N_("too many setup sectors")); |
| goto fail; |
| } |
| |
| - if (lh.version < grub_cpu_to_le16 (0x020b)) |
| + grub_dprintf ("linux", "checking lh->version\n"); |
| + if (lh->version < grub_cpu_to_le16 (0x020b)) |
| { |
| grub_error (GRUB_ERR_BAD_OS, N_("kernel too old")); |
| goto fail; |
| } |
| |
| - if (!lh.handover_offset) |
| + grub_dprintf ("linux", "checking lh->handover_offset\n"); |
| + if (!lh->handover_offset) |
| { |
| grub_error (GRUB_ERR_BAD_OS, N_("kernel doesn't support EFI handover")); |
| goto fail; |
| } |
| |
| +#if defined(__x86_64__) || defined(__aarch64__) |
| + grub_dprintf ("linux", "checking lh->xloadflags\n"); |
| + if (!(lh->xloadflags & LINUX_XLF_KERNEL_64)) |
| + { |
| + grub_error (GRUB_ERR_BAD_OS, N_("kernel doesn't support 64-bit CPUs")); |
| + goto fail; |
| + } |
| +#endif |
| + |
| +#if defined(__i386__) |
| + if ((lh->xloadflags & LINUX_XLF_KERNEL_64) && |
| + !(lh->xloadflags & LINUX_XLF_EFI_HANDOVER_32)) |
| + { |
| + grub_error (GRUB_ERR_BAD_OS, |
| + N_("kernel doesn't support 32-bit handover")); |
| + goto fail; |
| + } |
| +#endif |
| + |
| grub_dprintf ("linux", "setting up cmdline\n"); |
| linux_cmdline = grub_efi_allocate_pages_max(0x3fffffff, |
| - BYTES_TO_PAGES(lh.cmdline_size + 1)); |
| - |
| + BYTES_TO_PAGES(lh->cmdline_size + 1)); |
| if (!linux_cmdline) |
| { |
| grub_error (GRUB_ERR_OUT_OF_MEMORY, N_("can't allocate cmdline")); |
| @@ -255,21 +288,23 @@ grub_cmd_linux (grub_command_t cmd __attribute__ ((unused)), |
| grub_memcpy (linux_cmdline, LINUX_IMAGE, sizeof (LINUX_IMAGE)); |
| grub_create_loader_cmdline (argc, argv, |
| linux_cmdline + sizeof (LINUX_IMAGE) - 1, |
| - lh.cmdline_size - (sizeof (LINUX_IMAGE) - 1)); |
| + lh->cmdline_size - (sizeof (LINUX_IMAGE) - 1)); |
| |
| - lh.cmd_line_ptr = (grub_uint32_t)(grub_addr_t)linux_cmdline; |
| + grub_dprintf ("linux", "cmdline:%s\n", linux_cmdline); |
| + grub_dprintf ("linux", "setting lh->cmd_line_ptr\n"); |
| + lh->cmd_line_ptr = (grub_uint32_t)(grub_addr_t)linux_cmdline; |
| |
| - handover_offset = lh.handover_offset; |
| + grub_dprintf ("linux", "computing handover offset\n"); |
| + handover_offset = lh->handover_offset; |
| |
| - start = (lh.setup_sects + 1) * 512; |
| - len = grub_file_size(file) - start; |
| + start = (lh->setup_sects + 1) * 512; |
| |
| - kernel_mem = grub_efi_allocate_pages_max(lh.pref_address, |
| - BYTES_TO_PAGES(lh.init_size)); |
| + kernel_mem = grub_efi_allocate_pages_max(lh->pref_address, |
| + BYTES_TO_PAGES(lh->init_size)); |
| |
| if (!kernel_mem) |
| kernel_mem = grub_efi_allocate_pages_max(0x3fffffff, |
| - BYTES_TO_PAGES(lh.init_size)); |
| + BYTES_TO_PAGES(lh->init_size)); |
| |
| if (!kernel_mem) |
| { |
| @@ -277,14 +312,21 @@ grub_cmd_linux (grub_command_t cmd __attribute__ ((unused)), |
| goto fail; |
| } |
| |
| - grub_memcpy (kernel_mem, (char *)kernel + start, len); |
| + grub_dprintf ("linux", "kernel_mem = %lx\n", (unsigned long) kernel_mem); |
| + |
| grub_loader_set (grub_linuxefi_boot, grub_linuxefi_unload, 0); |
| loaded=1; |
| + grub_dprintf ("linux", "setting lh->code32_start to %p\n", kernel_mem); |
| + lh->code32_start = (grub_uint32_t)(grub_addr_t) kernel_mem; |
| |
| - lh.code32_start = (grub_uint32_t)(grub_uint64_t) kernel_mem; |
| - grub_memcpy (params, &lh, 2 * 512); |
| + grub_memcpy (kernel_mem, (char *)kernel + start, filelen - start); |
| |
| - params->type_of_loader = 0x21; |
| + grub_dprintf ("linux", "setting lh->type_of_loader\n"); |
| + lh->type_of_loader = 0x6; |
| + |
| + grub_dprintf ("linux", "setting lh->ext_loader_{type,ver}\n"); |
| + params->ext_loader_type = 0; |
| + params->ext_loader_ver = 2; |
| grub_dprintf("linux", "kernel_mem: %p handover_offset: %08x\n", |
| kernel_mem, handover_offset); |
| |
| @@ -301,10 +343,10 @@ grub_cmd_linux (grub_command_t cmd __attribute__ ((unused)), |
| loaded = 0; |
| } |
| |
| - if (linux_cmdline && !loaded) |
| + if (linux_cmdline && lh && !loaded) |
| grub_efi_free_pages ((grub_efi_physical_address_t)(grub_addr_t) |
| linux_cmdline, |
| - BYTES_TO_PAGES(lh.cmdline_size + 1)); |
| + BYTES_TO_PAGES(lh->cmdline_size + 1)); |
| |
| if (kernel_mem && !loaded) |
| grub_efi_free_pages ((grub_efi_physical_address_t)(grub_addr_t)kernel_mem, |
| diff --git a/include/grub/i386/linux.h b/include/grub/i386/linux.h |
| index bb19dbd5a77..8474a857ed2 100644 |
| |
| |
| @@ -133,7 +133,12 @@ struct linux_i386_kernel_header |
| grub_uint32_t kernel_alignment; |
| grub_uint8_t relocatable; |
| grub_uint8_t min_alignment; |
| - grub_uint8_t pad[2]; |
| +#define LINUX_XLF_KERNEL_64 (1<<0) |
| +#define LINUX_XLF_CAN_BE_LOADED_ABOVE_4G (1<<1) |
| +#define LINUX_XLF_EFI_HANDOVER_32 (1<<2) |
| +#define LINUX_XLF_EFI_HANDOVER_64 (1<<3) |
| +#define LINUX_XLF_EFI_KEXEC (1<<4) |
| + grub_uint16_t xloadflags; |
| grub_uint32_t cmdline_size; |
| grub_uint32_t hardware_subarch; |
| grub_uint64_t hardware_subarch_data; |