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riscv: remove limit on the size of read-only section for XIP kernel

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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. This causes
build failures if the kernel gets too big [1].

Remove this limit.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202404211031.J6l2AfJk-lkp@intel.com [1]
Signed-off-by: Nam Cao <namcao@linutronix.de>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/3bf3a77be10ebb0d8086c028500baa16e7a8e648.1717789719.git.namcao@linutronix.de
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
This commit is contained in:
Nam Cao 2024-06-07 22:22:13 +02:00 committed by Palmer Dabbelt
parent a7cfb99943
commit b635a84bde
No known key found for this signature in database
GPG Key ID: 2E1319F35FBB1889
3 changed files with 4 additions and 10 deletions
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7
arch/riscv/include/asm/pgtable.h
View File

@ -107,13 +107,6 @@
#endif
#ifdef CONFIG_XIP_KERNEL
#define XIP_OFFSET SZ_32M
#define XIP_OFFSET_MASK (SZ_32M - 1)
#else
#define XIP_OFFSET 0
#endif
#ifndef __ASSEMBLY__
#include <asm/page.h>

2
arch/riscv/include/asm/set_memory.h
View File

@ -46,7 +46,7 @@ bool kernel_page_present(struct page *page);
#endif /* __ASSEMBLY__ */
#ifdef CONFIG_STRICT_KERNEL_RWX
#if defined(CONFIG_STRICT_KERNEL_RWX) || defined(CONFIG_XIP_KERNEL)
#ifdef CONFIG_64BIT
#define SECTION_ALIGN (1 << 21)
#else

5
arch/riscv/kernel/vmlinux-xip.lds.S
View File

@ -14,6 +14,7 @@
#include <asm/page.h>
#include <asm/cache.h>
#include <asm/thread_info.h>
#include <asm/set_memory.h>
OUTPUT_ARCH(riscv)
ENTRY(_start)
@ -65,10 +66,10 @@ SECTIONS
* From this point, stuff is considered writable and will be copied to RAM
*/
__data_loc = ALIGN(PAGE_SIZE); /* location in file */
. = KERNEL_LINK_ADDR + XIP_OFFSET; /* location in memory */
. = ALIGN(SECTION_ALIGN); /* location in memory */
#undef LOAD_OFFSET
#define LOAD_OFFSET (KERNEL_LINK_ADDR + XIP_OFFSET - (__data_loc & XIP_OFFSET_MASK))
#define LOAD_OFFSET (KERNEL_LINK_ADDR + _sdata - __data_loc)
_sdata = .; /* Start of data section */
_data = .;