arm64: kexec_file: forbid kdump via kexec_file_load()

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 <bhsharma@redhat.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

diff --git a/arch/arm64/kernel/kexec_image.c b/arch/arm64/kernel/kexec_image.c
index 1ad1d5f8f024ec16a9a89bddaa5d18bcc901a295..07bf740bea914f5cdb813e6578943b8a65fef20c 100644 (file)
--- a/arch/arm64/kernel/kexec_image.c
+++ b/arch/arm64/kernel/kexec_image.c
@@ -47,6 +47,10 @@ static void *image_load(struct kimage *image,
        struct kexec_segment *kernel_segment;
        int ret;
 
+       /* We don't support crash kernels yet. */
+       if (image->type == KEXEC_TYPE_CRASH)
+               return ERR_PTR(-EOPNOTSUPP);
+
        /*
         * We require a kernel with an unambiguous Image header. Per
         * Documentation/booting.txt, this is the case when image_size