lkl: initialize mm constants before mem_init()#622
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lrh2000 wants to merge 1 commit intolkl:masterfrom
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lkl: initialize mm constants before mem_init()#622lrh2000 wants to merge 1 commit intolkl:masterfrom
lrh2000 wants to merge 1 commit intolkl:masterfrom
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max_mapnr is accessed through the following call chain: mem_init() -> memblock_free_all() -> free_low_memory_core_early() -> memmap_init_reserved_pages() -> reserve_bootmem_region() -> pfn_valid() -> (pfn - ARCH_PFN_OFFSET) < max_mapnr In lkl, max_mapnr is currently initialized in mem_init(), but only after memblock_free_all() runs. This means pfn_valid() can see an uninitialized max_mapnr and incorrectly return false for pfns that should be valid. For example, reserve_bootmem_region() should mark such pages as reserved, but due to this bug it does not. Other architectures, such as riscv, x86, and arm64, initialize mm constants before mem_init() from setup_arch(). Do the equivalent for lkl by initializing max_pfn, max_low_pfn, min_low_pfn, and max_mapnr in bootmem_init(). Signed-off-by: Ruihan Li <lrh2000@pku.edu.cn>
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max_mapnr is accessed through the following call chain:
In lkl, max_mapnr is currently initialized in mem_init(), but only after memblock_free_all() runs. This means pfn_valid() can see an uninitialized max_mapnr and incorrectly return false for pfns that should be valid.
For example, reserve_bootmem_region() should mark such pages as reserved, but due to this bug it does not.
Other architectures, such as riscv, x86, and arm64, initialize mm constants before mem_init() from setup_arch(). Do the equivalent for lkl by initializing max_pfn, max_low_pfn, min_low_pfn, and max_mapnr in bootmem_init().