From: Jinyang He hejinyang@loongson.cn
[ Upstream commit d4d3ef8b347b73aa60f60f4be06acf1643e79f34 ]
Provide kaslr_offset() to get the kernel offset when KASLR is enabled. Error may occur before update_kaslr_offset(), so put it at the end of the offset branch.
Fixes: a307a4ce9ecd ("MIPS: Loongson64: Add KASLR support") Reported-by: kernel test robot lkp@intel.com Signed-off-by: Jinyang He hejinyang@loongson.cn Signed-off-by: Thomas Bogendoerfer tsbogend@alpha.franken.de Signed-off-by: Sasha Levin sashal@kernel.org --- arch/mips/include/asm/page.h | 6 ++++++ arch/mips/kernel/relocate.c | 10 ++++++++++ arch/mips/kernel/setup.c | 3 +++ 3 files changed, 19 insertions(+)
diff --git a/arch/mips/include/asm/page.h b/arch/mips/include/asm/page.h index 6a77bc4a6eec4..74082e35d57c8 100644 --- a/arch/mips/include/asm/page.h +++ b/arch/mips/include/asm/page.h @@ -255,6 +255,12 @@ extern bool __virt_addr_valid(const volatile void *kaddr);
#define VM_DATA_DEFAULT_FLAGS VM_DATA_FLAGS_TSK_EXEC
+extern unsigned long __kaslr_offset; +static inline unsigned long kaslr_offset(void) +{ + return __kaslr_offset; +} + #include <asm-generic/memory_model.h> #include <asm-generic/getorder.h>
diff --git a/arch/mips/kernel/relocate.c b/arch/mips/kernel/relocate.c index 0e365b7c742d9..ac16cf2716df5 100644 --- a/arch/mips/kernel/relocate.c +++ b/arch/mips/kernel/relocate.c @@ -300,6 +300,13 @@ static inline int __init relocation_addr_valid(void *loc_new) return 1; }
+static inline void __init update_kaslr_offset(unsigned long *addr, long offset) +{ + unsigned long *new_addr = (unsigned long *)RELOCATED(addr); + + *new_addr = (unsigned long)offset; +} + #if defined(CONFIG_USE_OF) void __weak *plat_get_fdt(void) { @@ -410,6 +417,9 @@ void *__init relocate_kernel(void)
/* Return the new kernel's entry point */ kernel_entry = RELOCATED(start_kernel); + + /* Error may occur before, so keep it at last */ + update_kaslr_offset(&__kaslr_offset, offset); } out: return kernel_entry; diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c index 7e1f8e2774373..83ec0d5a0918b 100644 --- a/arch/mips/kernel/setup.c +++ b/arch/mips/kernel/setup.c @@ -84,6 +84,9 @@ static struct resource code_resource = { .name = "Kernel code", }; static struct resource data_resource = { .name = "Kernel data", }; static struct resource bss_resource = { .name = "Kernel bss", };
+unsigned long __kaslr_offset __ro_after_init; +EXPORT_SYMBOL(__kaslr_offset); + static void *detect_magic __initdata = detect_memory_region;
#ifdef CONFIG_MIPS_AUTO_PFN_OFFSET