Re: [PATCH 5/7] riscv: drop the use of XIP_OFFSET in kernel_mapping_va_to_pa()

From: Alexandre Ghiti
Date: Mon May 27 2024 - 08:50:07 EST



On 10/05/2024 08:28, Nam Cao wrote:
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 macro XIP_OFFSET entirely,
remove the use of XIP_OFFSET in kernel_mapping_va_to_pa(). The macro
XIP_OFFSET is used in this case to check if the virtual address is mapped
to Flash or to RAM. The same check can be done with kernel_map.xiprom_sz.

Signed-off-by: Nam Cao <namcao@xxxxxxxxxxxxx>
---
arch/riscv/include/asm/page.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/riscv/include/asm/page.h b/arch/riscv/include/asm/page.h
index 14d0de928f9b..bcd77df15835 100644
--- a/arch/riscv/include/asm/page.h
+++ b/arch/riscv/include/asm/page.h
@@ -159,7 +159,7 @@ phys_addr_t linear_mapping_va_to_pa(unsigned long x);
#ifdef CONFIG_XIP_KERNEL
#define kernel_mapping_va_to_pa(y) ({ \
unsigned long _y = (unsigned long)(y); \
- (_y < kernel_map.virt_addr + XIP_OFFSET) ? \
+ (_y < kernel_map.virt_addr + kernel_map.xiprom_sz) ? \
(_y - kernel_map.va_kernel_xip_pa_offset) : \
(_y - kernel_map.va_kernel_data_pa_offset); \
})


Reviewed-by: Alexandre Ghiti <alexghiti@xxxxxxxxxxxx>

Thanks,

Alex