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Alexandre Ghiti
ef69d2559f
riscv establishes 2 virtual mappings: - early_pg_dir maps the kernel which allows to discover the system memory - swapper_pg_dir installs the final mapping (linear mapping included) We used to map the dtb in early_pg_dir using DTB_EARLY_BASE_VA, and this mapping was not carried over in swapper_pg_dir. It happens that early_init_fdt_scan_reserved_mem() must be called before swapper_pg_dir is setup otherwise we could allocate reserved memory defined in the dtb. And this function initializes reserved_mem variable with addresses that lie in the early_pg_dir dtb mapping: when those addresses are reused with swapper_pg_dir, this mapping does not exist and then we trap. The previous "fix" was incorrect as early_init_fdt_scan_reserved_mem() must be called before swapper_pg_dir is set up otherwise we could allocate in reserved memory defined in the dtb. So move the dtb mapping in the fixmap region which is established in early_pg_dir and handed over to swapper_pg_dir. Fixes:922b0375fc("riscv: Fix memblock reservation for device tree blob") Fixes:8f3a2b4a96("RISC-V: Move DT mapping outof fixmap") Fixes:50e63dd8ed("riscv: fix reserved memory setup") Reported-by: Conor Dooley <[email protected]> Link: https://lore.kernel.org/all/[email protected]/ Signed-off-by: Alexandre Ghiti <[email protected]> Reviewed-by: Conor Dooley <[email protected]> Tested-by: Conor Dooley <[email protected]> Link: https://lore.kernel.org/r/[email protected] Cc: [email protected] Signed-off-by: Palmer Dabbelt <[email protected]>