| Message ID | 20240508191917.2892064-1-namcao@linutronix.de (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | riscv: change XIP's kernel_map.size to be size of the entire kernel | expand |
Hi Nam, On 08/05/2024 21:19, Nam Cao wrote: > With XIP kernel, kernel_map.size is set to be only the size of data part of > the kernel. This is inconsistent with "normal" kernel, who sets it to be > the size of the entire kernel. > > More importantly, XIP kernel fails to boot if CONFIG_DEBUG_VIRTUAL is > enabled, because there are checks on virtual addresses with the assumption > that kernel_map.size is the size of the entire kernel (these checks are in > arch/riscv/mm/physaddr.c). > > Change XIP's kernel_map.size to be the size of the entire kernel. > > Signed-off-by: Nam Cao <namcao@linutronix.de> > Cc: <stable@vger.kernel.org> # v6.1+ > --- > I wouldn't consider this inconsistency to be a bug. It only became a > a problem after kernel_map.size is used to check virtual addresses in > 5f763b3b5960 ("riscv: Fix DEBUG_VIRTUAL false warnings"). So I will only > backport this to stable versions that contain this commit: v6.1+ > > arch/riscv/mm/init.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c > index c081e7d349b1..0c0562839899 100644 > --- a/arch/riscv/mm/init.c > +++ b/arch/riscv/mm/init.c > @@ -903,7 +903,7 @@ static void __init create_kernel_page_table(pgd_t *pgdir, > PMD_SIZE, PAGE_KERNEL_EXEC); > > /* Map the data in RAM */ > - end_va = kernel_map.virt_addr + XIP_OFFSET + kernel_map.size; > + end_va = kernel_map.virt_addr + kernel_map.size; > for (va = kernel_map.virt_addr + XIP_OFFSET; va < end_va; va += PMD_SIZE) > create_pgd_mapping(pgdir, va, > kernel_map.phys_addr + (va - (kernel_map.virt_addr + XIP_OFFSET)), > @@ -1072,7 +1072,7 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa) > > phys_ram_base = CONFIG_PHYS_RAM_BASE; > kernel_map.phys_addr = (uintptr_t)CONFIG_PHYS_RAM_BASE; > - kernel_map.size = (uintptr_t)(&_end) - (uintptr_t)(&_sdata); > + kernel_map.size = (uintptr_t)(&_end) - (uintptr_t)(&_start); > > kernel_map.va_kernel_xip_pa_offset = kernel_map.virt_addr - kernel_map.xiprom; > #else You can add: Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> Thanks, Alex
diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index c081e7d349b1..0c0562839899 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -903,7 +903,7 @@ static void __init create_kernel_page_table(pgd_t *pgdir, PMD_SIZE, PAGE_KERNEL_EXEC); /* Map the data in RAM */ - end_va = kernel_map.virt_addr + XIP_OFFSET + kernel_map.size; + end_va = kernel_map.virt_addr + kernel_map.size; for (va = kernel_map.virt_addr + XIP_OFFSET; va < end_va; va += PMD_SIZE) create_pgd_mapping(pgdir, va, kernel_map.phys_addr + (va - (kernel_map.virt_addr + XIP_OFFSET)), @@ -1072,7 +1072,7 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa) phys_ram_base = CONFIG_PHYS_RAM_BASE; kernel_map.phys_addr = (uintptr_t)CONFIG_PHYS_RAM_BASE; - kernel_map.size = (uintptr_t)(&_end) - (uintptr_t)(&_sdata); + kernel_map.size = (uintptr_t)(&_end) - (uintptr_t)(&_start); kernel_map.va_kernel_xip_pa_offset = kernel_map.virt_addr - kernel_map.xiprom; #else
With XIP kernel, kernel_map.size is set to be only the size of data part of the kernel. This is inconsistent with "normal" kernel, who sets it to be the size of the entire kernel. More importantly, XIP kernel fails to boot if CONFIG_DEBUG_VIRTUAL is enabled, because there are checks on virtual addresses with the assumption that kernel_map.size is the size of the entire kernel (these checks are in arch/riscv/mm/physaddr.c). Change XIP's kernel_map.size to be the size of the entire kernel. Signed-off-by: Nam Cao <namcao@linutronix.de> Cc: <stable@vger.kernel.org> # v6.1+ --- I wouldn't consider this inconsistency to be a bug. It only became a a problem after kernel_map.size is used to check virtual addresses in 5f763b3b5960 ("riscv: Fix DEBUG_VIRTUAL false warnings"). So I will only backport this to stable versions that contain this commit: v6.1+ arch/riscv/mm/init.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)