linux-toradex.git/arch/arm64/kernel/kexec_image.c, branch v6.7

arm64: Fix dangling references to Documentation/arm64

2023-06-21T14:53:31+00:00

The arm64 documentation has moved under Documentation/arch/; fix up
references in the arm64 subtree to match.

Cc: Will Deacon 
Cc: Ard Biesheuvel 
Cc: linux-efi@vger.kernel.org
Acked-by: Catalin Marinas 
Signed-off-by: Jonathan Corbet

arm64: kexec_file: use more system keyrings to verify kernel image signature

2022-07-15T16:21:16+00:00

Currently, when loading a kernel image via the kexec_file_load() system
call, arm64 can only use the .builtin_trusted_keys keyring to verify
a signature whereas x86 can use three more keyrings i.e.
.secondary_trusted_keys, .machine and .platform keyrings. For example,
one resulting problem is kexec'ing a kernel image  would be rejected
with the error "Lockdown: kexec: kexec of unsigned images is restricted;
see man kernel_lockdown.7".

This patch set enables arm64 to make use of the same keyrings as x86 to
verify the signature kexec'ed kernel image.

Fixes: 732b7b93d849 ("arm64: kexec_file: add kernel signature verification support")
Cc: stable@vger.kernel.org # 105e10e2cf1c: kexec_file: drop weak attribute from functions
Cc: stable@vger.kernel.org # 34d5960af253: kexec: clean up arch_kexec_kernel_verify_sig
Cc: stable@vger.kernel.org # 83b7bb2d49ae: kexec, KEYS: make the code in bzImage64_verify_sig generic
Acked-by: Baoquan He 
Cc: kexec@lists.infradead.org
Cc: keyrings@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Co-developed-by: Michal Suchanek 
Signed-off-by: Michal Suchanek 
Acked-by: Will Deacon 
Signed-off-by: Coiby Xu 
Signed-off-by: Mimi Zohar

arm64: kexec_file: Fix sparse warning

2020-11-10T13:11:44+00:00

Sparse gets cross about us returning 0 from image_load(), which has a
return type of 'void *':

>> arch/arm64/kernel/kexec_image.c:130:16: sparse: sparse: Using plain integer as NULL pointer

Return NULL instead, as we don't use the return value for anything if it
does not indicate an error.

Cc: Benjamin Gwin 
Reported-by: kernel test robot 
Fixes: 108aa503657e ("arm64: kexec_file: try more regions if loading segments fails")
Link: https://lore.kernel.org/r/202011091736.T0zH8kaC-lkp@intel.com
Signed-off-by: Will Deacon

arm64: kexec_file: try more regions if loading segments fails

2020-11-05T21:48:05+00:00

It's possible that the first region picked for the new kernel will make
it impossible to fit the other segments in the required 32GB window,
especially if we have a very large initrd.

Instead of giving up, we can keep testing other regions for the kernel
until we find one that works.

Suggested-by: Ryan O'Leary 
Signed-off-by: Benjamin Gwin 
Link: https://lore.kernel.org/r/20201103201106.2397844-1-bgwin@google.com
Signed-off-by: Will Deacon

arm64: kexec_file: add crash dump support

2020-01-08T17:05:23+00:00

Enabling crash dump (kdump) includes
* prepare contents of ELF header of a core dump file, /proc/vmcore,
  using crash_prepare_elf64_headers(), and
* add two device tree properties, "linux,usable-memory-range" and
  "linux,elfcorehdr", which represent respectively a memory range
  to be used by crash dump kernel and the header's location

Signed-off-by: AKASHI Takahiro 
Cc: Catalin Marinas 
Cc: Will Deacon 
Reviewed-by: James Morse 
Tested-and-reviewed-by: Bhupesh Sharma 
Signed-off-by: Will Deacon

arm64/kexec: Use consistent convention of initializing 'kxec_buf.mem' with KEXEC_BUF_MEM_UNKNOWN

2019-08-05T10:06:33+00:00

With commit b6664ba42f14 ("s390, kexec_file: drop arch_kexec_mem_walk()"),
we introduced the KEXEC_BUF_MEM_UNKNOWN macro. If kexec_buf.mem is set
to this value, kexec_locate_mem_hole() will try to allocate free memory.

While other arch(s) like s390 and x86_64 already use this macro to
initialize kexec_buf.mem with, arm64 uses an equivalent value of 0.
Replace it with KEXEC_BUF_MEM_UNKNOWN, to keep the convention of
initializing 'kxec_buf.mem' consistent across various archs.

Cc: takahiro.akashi@linaro.org
Cc: james.morse@arm.com
Reviewed-by: Matthias Brugger 
Signed-off-by: Bhupesh Sharma 
Signed-off-by: Will Deacon

docs: arm64: convert docs to ReST and rename to .rst

2019-06-14T20:20:27+00:00

The documentation is in a format that is very close to ReST format.

The conversion is actually:
  - add blank lines in order to identify paragraphs;
  - fixing tables markups;
  - adding some lists markups;
  - marking literal blocks;
  - adjust some title markups.

At its new index.rst, let's add a :orphan: while this is not linked to
the main index.rst file, in order to avoid build warnings.

Signed-off-by: Mauro Carvalho Chehab 
Signed-off-by: Jonathan Corbet

docs: fix broken documentation links

2019-06-08T19:42:13+00:00

Mostly due to x86 and acpi conversion, several documentation
links are still pointing to the old file. Fix them.

Signed-off-by: Mauro Carvalho Chehab 
Reviewed-by: Wolfram Sang 
Reviewed-by: Sven Van Asbroeck 
Reviewed-by: Bhupesh Sharma 
Acked-by: Mark Brown 
Signed-off-by: Jonathan Corbet

arm64: kexec_file: forbid kdump via kexec_file_load()

2018-12-07T15:28:21+00:00

Now that kexec_walk_memblock() can do the crash-kernel placement itself
architectures that don't support kdump via kexe_file_load() need to
explicitly forbid it.

We don't support this on arm64 until the kernel can add the elfcorehdr
and usable-memory-range fields to the DT. Without these the crash-kernel
overwrites the previous kernel's memory during startup.

Add a check to refuse crash image loading.

Reviewed-by: Bhupesh Sharma 
Signed-off-by: James Morse 
Signed-off-by: Will Deacon

arm64: kexec_file: add kernel signature verification support

2018-12-06T15:16:52+00:00

With this patch, kernel verification can be done without IMA security
subsystem enabled. Turn on CONFIG_KEXEC_VERIFY_SIG instead.

On x86, a signature is embedded into a PE file (Microsoft's format) header
of binary. Since arm64's "Image" can also be seen as a PE file as far as
CONFIG_EFI is enabled, we adopt this format for kernel signing.

You can create a signed kernel image with:
    $ sbsign --key ${KEY} --cert ${CERT} Image

Signed-off-by: AKASHI Takahiro 
Cc: Catalin Marinas 
Cc: Will Deacon 
Reviewed-by: James Morse 
[will: removed useless pr_debug()]
Signed-off-by: Will Deacon