Commit f8863bc8 authored by Will Deacon's avatar Will Deacon
Browse files

Merge branch 'for-next/kdump' into for-next/core 

* for-next/kdump:
  arm64: kdump: defer the crashkernel reservation for platforms with no DMA memory zones
  arm64: kdump: do not map crashkernel region specifically
  arm64: kdump : take off the protection on crashkernel memory region
parents ea88dc92 504cae45

arch/arm64/include/asm/kexec.h

+0 −6
Original line number Diff line number Diff line
@@ -102,12 +102,6 @@ void cpu_soft_restart(unsigned long el2_switch, unsigned long entry, 


int machine_kexec_post_load(struct kimage *image);

#define machine_kexec_post_load machine_kexec_post_load



void arch_kexec_protect_crashkres(void);

#define arch_kexec_protect_crashkres arch_kexec_protect_crashkres



void arch_kexec_unprotect_crashkres(void);

#define arch_kexec_unprotect_crashkres arch_kexec_unprotect_crashkres

#endif



#define ARCH_HAS_KIMAGE_ARCH

arch/arm64/include/asm/memory.h

+0 −5
Original line number Diff line number Diff line
@@ -374,11 +374,6 @@ static inline void *phys_to_virt(phys_addr_t x) 
})



void dump_mem_limit(void);



static inline bool defer_reserve_crashkernel(void)

{

	return IS_ENABLED(CONFIG_ZONE_DMA) || IS_ENABLED(CONFIG_ZONE_DMA32);

}

#endif /* !ASSEMBLY */



/*

arch/arm64/kernel/machine_kexec.c

+0 −20
Original line number Diff line number Diff line
@@ -268,26 +268,6 @@ void machine_crash_shutdown(struct pt_regs *regs) 
	pr_info("Starting crashdump kernel...\n");

}



void arch_kexec_protect_crashkres(void)

{

	int i;



	for (i = 0; i < kexec_crash_image->nr_segments; i++)

		set_memory_valid(

			__phys_to_virt(kexec_crash_image->segment[i].mem),

			kexec_crash_image->segment[i].memsz >> PAGE_SHIFT, 0);

}



void arch_kexec_unprotect_crashkres(void)

{

	int i;



	for (i = 0; i < kexec_crash_image->nr_segments; i++)

		set_memory_valid(

			__phys_to_virt(kexec_crash_image->segment[i].mem),

			kexec_crash_image->segment[i].memsz >> PAGE_SHIFT, 1);

}



#ifdef CONFIG_HIBERNATION

/*

 * To preserve the crash dump kernel image, the relevant memory segments

arch/arm64/mm/init.c

+3 −31
Original line number Diff line number Diff line
@@ -61,34 +61,8 @@ EXPORT_SYMBOL(memstart_addr); 
 * unless restricted on specific platforms (e.g. 30-bit on Raspberry Pi 4).

 * In such case, ZONE_DMA32 covers the rest of the 32-bit addressable memory,

 * otherwise it is empty.

 *

 * Memory reservation for crash kernel either done early or deferred

 * depending on DMA memory zones configs (ZONE_DMA) --

 *

 * In absence of ZONE_DMA configs arm64_dma_phys_limit initialized

 * here instead of max_zone_phys().  This lets early reservation of

 * crash kernel memory which has a dependency on arm64_dma_phys_limit.

 * Reserving memory early for crash kernel allows linear creation of block

 * mappings (greater than page-granularity) for all the memory bank rangs.

 * In this scheme a comparatively quicker boot is observed.

 *

 * If ZONE_DMA configs are defined, crash kernel memory reservation

 * is delayed until DMA zone memory range size initialization performed in

 * zone_sizes_init().  The defer is necessary to steer clear of DMA zone

 * memory range to avoid overlap allocation.  So crash kernel memory boundaries

 * are not known when mapping all bank memory ranges, which otherwise means

 * not possible to exclude crash kernel range from creating block mappings

 * so page-granularity mappings are created for the entire memory range.

 * Hence a slightly slower boot is observed.

 *

 * Note: Page-granularity mappings are necessary for crash kernel memory

 * range for shrinking its size via /sys/kernel/kexec_crash_size interface.

 */

#if IS_ENABLED(CONFIG_ZONE_DMA) || IS_ENABLED(CONFIG_ZONE_DMA32)

phys_addr_t __ro_after_init arm64_dma_phys_limit;

#else

phys_addr_t __ro_after_init arm64_dma_phys_limit = PHYS_MASK + 1;

#endif



/* Current arm64 boot protocol requires 2MB alignment */

#define CRASH_ALIGN			SZ_2M
@@ -248,6 +222,8 @@ static void __init zone_sizes_init(void) 
	if (!arm64_dma_phys_limit)

		arm64_dma_phys_limit = dma32_phys_limit;

#endif

	if (!arm64_dma_phys_limit)

		arm64_dma_phys_limit = PHYS_MASK + 1;

	max_zone_pfns[ZONE_NORMAL] = max_pfn;



	free_area_init(max_zone_pfns);
@@ -408,9 +384,6 @@ void __init arm64_memblock_init(void) 


	early_init_fdt_scan_reserved_mem();



	if (!defer_reserve_crashkernel())

		reserve_crashkernel();



	high_memory = __va(memblock_end_of_DRAM() - 1) + 1;

}
@@ -457,7 +430,6 @@ void __init bootmem_init(void) 
	 * request_standard_resources() depends on crashkernel's memory being

	 * reserved, so do it here.

	 */

	if (defer_reserve_crashkernel())

	reserve_crashkernel();



	memblock_dump_all();

arch/arm64/mm/mmu.c

+0 −43
Original line number Diff line number Diff line
@@ -510,21 +510,6 @@ void __init mark_linear_text_alias_ro(void) 
			    PAGE_KERNEL_RO);

}



static bool crash_mem_map __initdata;



static int __init enable_crash_mem_map(char *arg)

{

	/*

	 * Proper parameter parsing is done by reserve_crashkernel(). We only

	 * need to know if the linear map has to avoid block mappings so that

	 * the crashkernel reservations can be unmapped later.

	 */

	crash_mem_map = true;



	return 0;

}

early_param("crashkernel", enable_crash_mem_map);



static void __init map_mem(pgd_t *pgdp)

{

	static const u64 direct_map_end = _PAGE_END(VA_BITS_MIN);
@@ -554,16 +539,6 @@ static void __init map_mem(pgd_t *pgdp) 
	 */

	memblock_mark_nomap(kernel_start, kernel_end - kernel_start);



#ifdef CONFIG_KEXEC_CORE

	if (crash_mem_map) {

		if (defer_reserve_crashkernel())

			flags |= NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS;

		else if (crashk_res.end)

			memblock_mark_nomap(crashk_res.start,

			    resource_size(&crashk_res));

	}

#endif



	/* map all the memory banks */

	for_each_mem_range(i, &start, &end) {

		if (start >= end)
@@ -590,24 +565,6 @@ static void __init map_mem(pgd_t *pgdp) 
	__map_memblock(pgdp, kernel_start, kernel_end,

		       PAGE_KERNEL, NO_CONT_MAPPINGS);

	memblock_clear_nomap(kernel_start, kernel_end - kernel_start);



	/*

	 * Use page-level mappings here so that we can shrink the region

	 * in page granularity and put back unused memory to buddy system

	 * through /sys/kernel/kexec_crash_size interface.

	 */

#ifdef CONFIG_KEXEC_CORE

	if (crash_mem_map && !defer_reserve_crashkernel()) {

		if (crashk_res.end) {

			__map_memblock(pgdp, crashk_res.start,

				       crashk_res.end + 1,

				       PAGE_KERNEL,

				       NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS);

			memblock_clear_nomap(crashk_res.start,

					     resource_size(&crashk_res));

		}

	}

#endif

}



void mark_rodata_ro(void)