From: AKASHI Takahiro Date: Thu, 15 Nov 2018 05:52:52 +0000 (+0900) Subject: arm64: kexec_file: invoke the kernel without purgatory X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=4c9e7e649a3f291e1b939299458e6844c16afe70;p=linux.git 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: AKASHI Takahiro Reviewed-by: James Morse Cc: Catalin Marinas Cc: Will Deacon Signed-off-by: Will Deacon --- diff --git a/arch/arm64/kernel/cpu-reset.S b/arch/arm64/kernel/cpu-reset.S index 8021b46c97431..a2be30275a73c 100644 --- a/arch/arm64/kernel/cpu-reset.S +++ b/arch/arm64/kernel/cpu-reset.S @@ -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 diff --git a/arch/arm64/kernel/machine_kexec.c b/arch/arm64/kernel/machine_kexec.c index 922add8adb749..aa9c94113700e 100644 --- a/arch/arm64/kernel/machine_kexec.c +++ b/arch/arm64/kernel/machine_kexec.c @@ -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. */ } diff --git a/arch/arm64/kernel/relocate_kernel.S b/arch/arm64/kernel/relocate_kernel.S index f407e422a7200..95fd94209aaeb 100644 --- a/arch/arm64/kernel/relocate_kernel.S +++ b/arch/arm64/kernel/relocate_kernel.S @@ -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