In commit 031495635b46 ("arm64: Do not defer reserve_crashkernel() for platforms with no DMA memory zones"), reserve_crashkernel() is called much earlier in arm64_memblock_init() to avoid causing base apge mapping on platforms with no DMA meomry zones. With taking off protection on crashkernel memory region, no need to call reserve_crashkernel() specially in advance. The deferred invocation of reserve_crashkernel() in bootmem_init() can cover all cases. So revert the commit 031495635b46 now. Signed-off-by: Baoquan He <bhe@xxxxxxxxxx> --- v1->v2: - When trying to revert commit 031495635b46, two hunks were missed in v1 post. Remove them in v2. Thanks to Leizhen for pointing out this. - Remove code comment above arm64_dma_phys_limit definition added in commit 031495635b46; - Move the arm64_dma_phys_limit assignment back into zone_sizes_init() when both CONFIG_ZONE_DMA and CONFIG_ZONE_DMA32 are not enabled. arch/arm64/include/asm/memory.h | 5 ----- arch/arm64/mm/init.c | 34 +++------------------------------ 2 files changed, 3 insertions(+), 36 deletions(-) diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h index 78e5163836a0..efcd68154a3a 100644 --- a/arch/arm64/include/asm/memory.h +++ b/arch/arm64/include/asm/memory.h @@ -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 */ /* diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index 58a0bb2c17f1..66e70ca47680 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -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; } @@ -457,8 +430,7 @@ 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(); + reserve_crashkernel(); memblock_dump_all(); } -- 2.34.1 _______________________________________________ kexec mailing list kexec@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/kexec