[PATCH 3/3] arm64: kdump: defer the crashkernel reservation for platforms with no DMA memory zones

From: Baoquan He
Date: Fri Mar 24 2023 - 09:20:07 EST


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.

Signed-off-by: Baoquan He <bhe@xxxxxxxxxx>
---
arch/arm64/include/asm/memory.h | 5 -----
arch/arm64/mm/init.c | 6 +-----
2 files changed, 1 insertion(+), 10 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..b888de59e0b7 100644
--- a/arch/arm64/mm/init.c
+++ b/arch/arm64/mm/init.c
@@ -408,9 +408,6 @@ 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 +454,7 @@ 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