From a7cfb999433ad3a1aa7ca86ecdaf3e061ab7076a Mon Sep 17 00:00:00 2001 From: Nam Cao Date: Fri, 7 Jun 2024 22:22:12 +0200 Subject: [PATCH] riscv: drop the use of XIP_OFFSET in create_kernel_page_table() XIP_OFFSET is the hard-coded offset of writable data section within the kernel. By hard-coding this value, the read-only section of the kernel (which is placed before the writable data section) is restricted in size. As a preparation to remove this hard-coded value entirely, stop using XIP_OFFSET in create_kernel_page_table(). Instead use _sdata and _start to do the same thing. Signed-off-by: Nam Cao Reviewed-by: Alexandre Ghiti Link: https://lore.kernel.org/r/4ea3f222a7eb9f91c04b155ff2e4d3ef19158acc.1717789719.git.namcao@linutronix.de Signed-off-by: Palmer Dabbelt --- arch/riscv/mm/init.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index c2d63808d7abf..31b23f84494f4 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -917,7 +917,7 @@ static void __init relocate_kernel(void) static void __init create_kernel_page_table(pgd_t *pgdir, __always_unused bool early) { - uintptr_t va, end_va; + uintptr_t va, start_va, end_va; /* Map the flash resident part */ end_va = kernel_map.virt_addr + kernel_map.xiprom_sz; @@ -927,10 +927,11 @@ static void __init create_kernel_page_table(pgd_t *pgdir, PMD_SIZE, PAGE_KERNEL_EXEC); /* Map the data in RAM */ + start_va = kernel_map.virt_addr + (uintptr_t)&_sdata - (uintptr_t)&_start; end_va = kernel_map.virt_addr + kernel_map.size; - for (va = kernel_map.virt_addr + XIP_OFFSET; va < end_va; va += PMD_SIZE) + for (va = start_va; va < end_va; va += PMD_SIZE) create_pgd_mapping(pgdir, va, - kernel_map.phys_addr + (va - (kernel_map.virt_addr + XIP_OFFSET)), + kernel_map.phys_addr + (va - start_va), PMD_SIZE, PAGE_KERNEL); } #else -- 2.39.5