diff mbox

[v7,2/2] aarch64: Allow -kernel option to take a gzip-compressed kernel.

Message ID 1407525459-9181-3-git-send-email-rjones@redhat.com
State New
Headers show

Commit Message

Richard W.M. Jones Aug. 8, 2014, 7:17 p.m. UTC
On aarch64 it is the bootloader's job to uncompress the kernel.  UEFI
and u-boot bootloaders do this automatically when the kernel is
gzip-compressed.

However the qemu -kernel option does not do this.  The following
command does not work:

  qemu-system-aarch64 [...] -kernel /boot/vmlinuz

because it tries to execute the gzip-compressed data.

This commit lets gzip-compressed kernels be uncompressed
transparently.

Currently this is only done when emulating aarch64.

Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
---
 hw/arm/boot.c | 9 +++++++++
 1 file changed, 9 insertions(+)

Comments

Peter Crosthwaite Aug. 12, 2014, 1:50 a.m. UTC | #1
On Sat, Aug 9, 2014 at 5:17 AM, Richard W.M. Jones <rjones@redhat.com> wrote:
> On aarch64 it is the bootloader's job to uncompress the kernel.  UEFI
> and u-boot bootloaders do this automatically when the kernel is
> gzip-compressed.
>
> However the qemu -kernel option does not do this.  The following
> command does not work:
>
>   qemu-system-aarch64 [...] -kernel /boot/vmlinuz
>
> because it tries to execute the gzip-compressed data.
>
> This commit lets gzip-compressed kernels be uncompressed
> transparently.
>
> Currently this is only done when emulating aarch64.
>
> Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
> Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
> ---
>  hw/arm/boot.c | 9 +++++++++
>  1 file changed, 9 insertions(+)
>
> diff --git a/hw/arm/boot.c b/hw/arm/boot.c
> index 1241761..c71c4d5 100644
> --- a/hw/arm/boot.c
> +++ b/hw/arm/boot.c
> @@ -448,6 +448,7 @@ static void do_cpu_reset(void *opaque)
>  void arm_load_kernel(ARMCPU *cpu, struct arm_boot_info *info)
>  {
>      CPUState *cs = CPU(cpu);
> +    int allow_compressed_kernels = 0;

Use a bool. And I think this can be better names is_aarch64 (or just
dropped completely and users use arm_feature(ARM_FEATURE_AARCH64)
inline).

Otherwise:

Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>

>      int kernel_size;
>      int initrd_size;
>      int is_linux = 0;
> @@ -469,6 +470,7 @@ void arm_load_kernel(ARMCPU *cpu, struct arm_boot_info *info)
>          primary_loader = bootloader_aarch64;
>          kernel_load_offset = KERNEL64_LOAD_ADDR;
>          elf_machine = EM_AARCH64;
> +        allow_compressed_kernels = 1;
>      } else {
>          primary_loader = bootloader;
>          kernel_load_offset = KERNEL_LOAD_ADDR;
> @@ -514,6 +516,13 @@ void arm_load_kernel(ARMCPU *cpu, struct arm_boot_info *info)
>          kernel_size = load_uimage(info->kernel_filename, &entry, NULL,
>                                    &is_linux);
>      }
> +    /* On aarch64, it's the bootloader's job to uncompress the kernel. */
> +    if (allow_compressed_kernels && 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);
> +        is_linux = 1;
> +    }
>      if (kernel_size < 0) {
>          entry = info->loader_start + kernel_load_offset;
>          kernel_size = load_image_targphys(info->kernel_filename, entry,
> --
> 2.0.4
>
>
diff mbox

Patch

diff --git a/hw/arm/boot.c b/hw/arm/boot.c
index 1241761..c71c4d5 100644
--- a/hw/arm/boot.c
+++ b/hw/arm/boot.c
@@ -448,6 +448,7 @@  static void do_cpu_reset(void *opaque)
 void arm_load_kernel(ARMCPU *cpu, struct arm_boot_info *info)
 {
     CPUState *cs = CPU(cpu);
+    int allow_compressed_kernels = 0;
     int kernel_size;
     int initrd_size;
     int is_linux = 0;
@@ -469,6 +470,7 @@  void arm_load_kernel(ARMCPU *cpu, struct arm_boot_info *info)
         primary_loader = bootloader_aarch64;
         kernel_load_offset = KERNEL64_LOAD_ADDR;
         elf_machine = EM_AARCH64;
+        allow_compressed_kernels = 1;
     } else {
         primary_loader = bootloader;
         kernel_load_offset = KERNEL_LOAD_ADDR;
@@ -514,6 +516,13 @@  void arm_load_kernel(ARMCPU *cpu, struct arm_boot_info *info)
         kernel_size = load_uimage(info->kernel_filename, &entry, NULL,
                                   &is_linux);
     }
+    /* On aarch64, it's the bootloader's job to uncompress the kernel. */
+    if (allow_compressed_kernels && 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);
+        is_linux = 1;
+    }
     if (kernel_size < 0) {
         entry = info->loader_start + kernel_load_offset;
         kernel_size = load_image_targphys(info->kernel_filename, entry,