Commit c8168b4f authored by Youling Tang's avatar Youling Tang Committed by Huacai Chen
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LoongArch: Automatically disable kaslr if boot from kexec_file 



Automatically disable kaslr when the kernel loads from kexec_file.

kexec_file loads the secondary kernel image to a non-linked address,
inherently providing KASLR-like randomization.

However, on LoongArch where System RAM may be non-contiguous, enabling
KASLR for the second kernel may relocate it to an invalid memory region
and cause a boot failure. Thus, we disable KASLR when "kexec_file" is
detected in the command line.

To ensure compatibility with older kernels loaded via kexec_file, this
patch should be backported to stable branches.

Cc: stable@vger.kernel.org
Signed-off-by: default avatarYouling Tang <tangyouling@kylinos.cn>
Signed-off-by: default avatarHuacai Chen <chenhuacai@loongson.cn>
parent 1bcca862

arch/loongarch/kernel/relocate.c

+4 −0
Original line number Diff line number Diff line
@@ -166,6 +166,10 @@ static inline __init bool kaslr_disabled(void) 
		return true;

#endif



	str = strstr(boot_command_line, "kexec_file");

	if (str == boot_command_line || (str > boot_command_line && *(str - 1) == ' '))

		return true;



	return false;

}