| Message ID | 1489414630-21609-1-git-send-email-ard.biesheuvel@linaro.org |
|---|---|
| State | Superseded |
| Headers | show |
On 13 March 2017 at 14:17, Ard Biesheuvel <ard.biesheuvel@linaro.org> wrote: > The arm64 boot protocol stipulates that the kernel must be loaded > TEXT_OFFSET bytes beyond a 2 MB aligned base address, where TEXT_OFFSET > could be any 4 KB multiple between 0 and 2 MB, and whose value can be > found in the header of the Image file. > > So after attempts to load the arm64 kernel image as an ELF file or as a > U-Boot image have failed (both of which have their own way of specifying > the load offset), try to determine the TEXT_OFFSET from the image after > loading it but before mapping it as a ROM mapping into the guest address > space. > > Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> > --- > v2: split off AArch64 specific loader logic regarding gzipped/raw and variable > load offset into a separate helper function, which removes the need for > loading the image twice Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Since we're due to tag rc1 tomorrow and this is kind of on the border between bugfix and new feature, I think I'd rather defer it to 2.10, unless you have a strong view that it should go into 2.9. thanks -- PMM
On 20 March 2017 at 11:13, Peter Maydell <peter.maydell@linaro.org> wrote: > On 13 March 2017 at 14:17, Ard Biesheuvel <ard.biesheuvel@linaro.org> wrote: >> The arm64 boot protocol stipulates that the kernel must be loaded >> TEXT_OFFSET bytes beyond a 2 MB aligned base address, where TEXT_OFFSET >> could be any 4 KB multiple between 0 and 2 MB, and whose value can be >> found in the header of the Image file. >> >> So after attempts to load the arm64 kernel image as an ELF file or as a >> U-Boot image have failed (both of which have their own way of specifying >> the load offset), try to determine the TEXT_OFFSET from the image after >> loading it but before mapping it as a ROM mapping into the guest address >> space. >> >> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> >> --- >> v2: split off AArch64 specific loader logic regarding gzipped/raw and variable >> load offset into a separate helper function, which removes the need for >> loading the image twice > > Reviewed-by: Peter Maydell <peter.maydell@linaro.org> > Thanks > Since we're due to tag rc1 tomorrow and this is kind of on the > border between bugfix and new feature, I think I'd rather > defer it to 2.10, unless you have a strong view that it should > go into 2.9. > I will leave that to you to decide, I don't feel strongly either way
On 20 March 2017 at 11:13, Peter Maydell <peter.maydell@linaro.org> wrote: > On 13 March 2017 at 14:17, Ard Biesheuvel <ard.biesheuvel@linaro.org> wrote: >> The arm64 boot protocol stipulates that the kernel must be loaded >> TEXT_OFFSET bytes beyond a 2 MB aligned base address, where TEXT_OFFSET >> could be any 4 KB multiple between 0 and 2 MB, and whose value can be >> found in the header of the Image file. >> >> So after attempts to load the arm64 kernel image as an ELF file or as a >> U-Boot image have failed (both of which have their own way of specifying >> the load offset), try to determine the TEXT_OFFSET from the image after >> loading it but before mapping it as a ROM mapping into the guest address >> space. >> >> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> >> --- >> v2: split off AArch64 specific loader logic regarding gzipped/raw and variable >> load offset into a separate helper function, which removes the need for >> loading the image twice > > Reviewed-by: Peter Maydell <peter.maydell@linaro.org> > > Since we're due to tag rc1 tomorrow and this is kind of on the > border between bugfix and new feature, I think I'd rather > defer it to 2.10, unless you have a strong view that it should > go into 2.9. Since we're now at rc3 and I don't expect to need to do another arm pull request before 2.9, I've put this patch into target-arm.next for 2.10. thanks -- PMM
diff --git a/hw/arm/boot.c b/hw/arm/boot.c index ff621e4b6a4b..c2720c80460f 100644 --- a/hw/arm/boot.c +++ b/hw/arm/boot.c @@ -31,6 +31,9 @@ #define KERNEL_LOAD_ADDR 0x00010000 #define KERNEL64_LOAD_ADDR 0x00080000 +#define ARM64_TEXT_OFFSET_OFFSET 8 +#define ARM64_MAGIC_OFFSET 56 + typedef enum { FIXUP_NONE = 0, /* do nothing */ FIXUP_TERMINATOR, /* end of insns */ @@ -768,6 +771,49 @@ static uint64_t arm_load_elf(struct arm_boot_info *info, uint64_t *pentry, return ret; } +static uint64_t load_aarch64_image(const char *filename, hwaddr mem_base, + hwaddr *entry) +{ + hwaddr kernel_load_offset = KERNEL64_LOAD_ADDR; + uint8_t *buffer; + int size; + + /* On aarch64, it's the bootloader's job to uncompress the kernel. */ + size = load_image_gzipped_buffer(filename, LOAD_IMAGE_MAX_GUNZIP_BYTES, + &buffer); + + if (size < 0) { + gsize len; + + /* Load as raw file otherwise */ + if (!g_file_get_contents(filename, (char **)&buffer, &len, NULL)) { + return -1; + } + size = len; + } + + /* check the arm64 magic header value -- very old kernels may not have it */ + if (memcmp(buffer + ARM64_MAGIC_OFFSET, "ARM\x64", 4) == 0) { + uint64_t hdrvals[2]; + + /* The arm64 Image header has text_offset and image_size fields at 8 and + * 16 bytes into the Image header, respectively. The text_offset field + * is only valid if the image_size is non-zero. + */ + memcpy(&hdrvals, buffer + ARM64_TEXT_OFFSET_OFFSET, sizeof(hdrvals)); + if (hdrvals[1] != 0) { + kernel_load_offset = le64_to_cpu(hdrvals[0]); + } + } + + *entry = mem_base + kernel_load_offset; + rom_add_blob_fixed(filename, buffer, size, *entry); + + g_free(buffer); + + return size; +} + static void arm_load_kernel_notify(Notifier *notifier, void *data) { CPUState *cs; @@ -776,7 +822,7 @@ static void arm_load_kernel_notify(Notifier *notifier, void *data) int is_linux = 0; uint64_t elf_entry, elf_low_addr, elf_high_addr; int elf_machine; - hwaddr entry, kernel_load_offset; + hwaddr entry; static const ARMInsnFixup *primary_loader; ArmLoadKernelNotifier *n = DO_UPCAST(ArmLoadKernelNotifier, notifier, notifier); @@ -841,14 +887,12 @@ static void arm_load_kernel_notify(Notifier *notifier, void *data) if (arm_feature(&cpu->env, ARM_FEATURE_AARCH64)) { primary_loader = bootloader_aarch64; - kernel_load_offset = KERNEL64_LOAD_ADDR; elf_machine = EM_AARCH64; } else { primary_loader = bootloader; if (!info->write_board_setup) { primary_loader += BOOTLOADER_NO_BOARD_SETUP_OFFSET; } - kernel_load_offset = KERNEL_LOAD_ADDR; elf_machine = EM_ARM; } @@ -900,17 +944,15 @@ static void arm_load_kernel_notify(Notifier *notifier, void *data) kernel_size = load_uimage(info->kernel_filename, &entry, NULL, &is_linux, NULL, NULL); } - /* On aarch64, it's the bootloader's job to uncompress the kernel. */ if (arm_feature(&cpu->env, ARM_FEATURE_AARCH64) && kernel_size < 0) { - entry = info->loader_start + kernel_load_offset; - kernel_size = load_image_gzipped(info->kernel_filename, entry, - info->ram_size - kernel_load_offset); + kernel_size = load_aarch64_image(info->kernel_filename, + info->loader_start, &entry); is_linux = 1; - } - if (kernel_size < 0) { - entry = info->loader_start + kernel_load_offset; + } else if (kernel_size < 0) { + /* 32-bit ARM */ + entry = info->loader_start + KERNEL_LOAD_ADDR; kernel_size = load_image_targphys(info->kernel_filename, entry, - info->ram_size - kernel_load_offset); + info->ram_size - KERNEL_LOAD_ADDR); is_linux = 1; } if (kernel_size < 0) {
The arm64 boot protocol stipulates that the kernel must be loaded TEXT_OFFSET bytes beyond a 2 MB aligned base address, where TEXT_OFFSET could be any 4 KB multiple between 0 and 2 MB, and whose value can be found in the header of the Image file. So after attempts to load the arm64 kernel image as an ELF file or as a U-Boot image have failed (both of which have their own way of specifying the load offset), try to determine the TEXT_OFFSET from the image after loading it but before mapping it as a ROM mapping into the guest address space. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> --- v2: split off AArch64 specific loader logic regarding gzipped/raw and variable load offset into a separate helper function, which removes the need for loading the image twice hw/arm/boot.c | 64 ++++++++++++++++---- 1 file changed, 53 insertions(+), 11 deletions(-) -- 2.7.4