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arch/x86/include/asm/boot.h

LOAD_PHYSICAL_ADDR

LOAD_PHYSICAL_ADDR is the physical address at which the kernel should be loaded.
This value is defined as 
#define LOAD_PHYSICAL_ADDR ((CONFIG_PHYSICAL_START \
                                + (CONFIG_PHYSICAL_ALIGN - 1)) \
                                & ~(CONFIG_PHYSICAL_ALIGN - 1))
The default of CONFIG_PHYSICAL_START is 0x1000000.
See also decompressing the kernel.

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