慢慢欣赏arm64内核启动30 __primary_switched之第三部分

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已于 2024-11-13 08:41:01 修改 · 574 阅读

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#linux

于 2024-10-17 09:06:22 首次发布

展示代码

	str_l	x21, __fdt_pointer, x5		// Save FDT pointer

	ldr_l	x4, kimage_vaddr		// Save the offset between
	sub	x4, x4, x0			// the kernel virtual and
	str_l	x4, kimage_voffset, x5		// physical mappings

	// Clear BSS
	adr_l	x0, __bss_start
	mov	x1, xzr
	adr_l	x2, __bss_stop
	sub	x2, x2, x0
	bl	__pi_memset
	dsb	ishst				// Make zero page visible to PTW

#ifdef CONFIG_KASAN
	bl	kasan_early_init
#endif
#ifdef CONFIG_RANDOMIZE_BASE
	tst	x23, ~(MIN_KIMG_ALIGN - 1)	// already running randomized?
	b.ne	0f
	mov	x0, x21				// pass FDT address in x0
	bl	kaslr_early_init		// parse FDT for KASLR options
	cbz	x0, 0f				// KASLR disabled? just proceed
	orr	x23, x23, x0			// record KASLR offset
	ldp	x29, x30, [sp], #16		// we must enable KASLR, return
	ret					// to __primary_switch()
0:
#endif
	add	sp, sp, #16
	mov	x29, #0
	mov	x30, #0
	b	start_kernel
SYM_FUNC_END(__primary_switched)