Commit 4c9e7e64 authored by AKASHI Takahiro's avatar AKASHI Takahiro Committed by Will Deacon
Browse files

arm64: kexec_file: invoke the kernel without purgatory 



On arm64, purgatory would do almost nothing. So just invoke secondary
kernel directly by jumping into its entry code.

While, in this case, cpu_soft_restart() must be called with dtb address
in the fifth argument, the behavior still stays compatible with kexec_load
case as long as the argument is null.

Signed-off-by: default avatarAKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: default avatarJames Morse <james.morse@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
parent f3b70e50

arch/arm64/kernel/cpu-reset.S

+4 −4
Original line number Diff line number Diff line
@@ -22,11 +22,11 @@ 
 * __cpu_soft_restart(el2_switch, entry, arg0, arg1, arg2) - Helper for

 * cpu_soft_restart.

 *

 * @el2_switch: Flag to indicate a swich to EL2 is needed.

 * @el2_switch: Flag to indicate a switch to EL2 is needed.

 * @entry: Location to jump to for soft reset.

 * arg0: First argument passed to @entry.

 * arg1: Second argument passed to @entry.

 * arg2: Third argument passed to @entry.

 * arg0: First argument passed to @entry. (relocation list)

 * arg1: Second argument passed to @entry.(physical kernel entry)

 * arg2: Third argument passed to @entry. (physical dtb address)

 *

 * Put the CPU into the same state as it would be if it had been reset, and

 * branch to what would be the reset vector. It must be executed with the

arch/arm64/kernel/machine_kexec.c

+10 −2
Original line number Diff line number Diff line
@@ -212,9 +212,17 @@ void machine_kexec(struct kimage *kimage) 
	 * uses physical addressing to relocate the new image to its final

	 * position and transfers control to the image entry point when the

	 * relocation is complete.

	 * In kexec case, kimage->start points to purgatory assuming that

	 * kernel entry and dtb address are embedded in purgatory by

	 * userspace (kexec-tools).

	 * In kexec_file case, the kernel starts directly without purgatory.

	 */



	cpu_soft_restart(reboot_code_buffer_phys, kimage->head, kimage->start, 0);

	cpu_soft_restart(reboot_code_buffer_phys, kimage->head, kimage->start,

#ifdef CONFIG_KEXEC_FILE

						kimage->arch.dtb_mem);

#else

						0);

#endif



	BUG(); /* Should never get here. */

}

arch/arm64/kernel/relocate_kernel.S

+2 −1
Original line number Diff line number Diff line
@@ -32,6 +32,7 @@ 
ENTRY(arm64_relocate_new_kernel)



	/* Setup the list loop variables. */

	mov	x18, x2				/* x18 = dtb address */

	mov	x17, x1				/* x17 = kimage_start */

	mov	x16, x0				/* x16 = kimage_head */

	raw_dcache_line_size x15, x0		/* x15 = dcache line size */
@@ -107,7 +108,7 @@ ENTRY(arm64_relocate_new_kernel) 
	isb



	/* Start new image. */

	mov	x0, xzr

	mov	x0, x18

	mov	x1, xzr

	mov	x2, xzr

	mov	x3, xzr

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