diff options
Diffstat (limited to 'arch/riscv/kernel/entry.S')
| -rw-r--r-- | arch/riscv/kernel/entry.S | 36 |
1 files changed, 25 insertions, 11 deletions
diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S index 33a5a9f2a0d4..9b9dec6893b8 100644 --- a/arch/riscv/kernel/entry.S +++ b/arch/riscv/kernel/entry.S @@ -7,6 +7,7 @@ #include <linux/init.h> #include <linux/linkage.h> +#include <asm/alternative-macros.h> #include <asm/asm.h> #include <asm/csr.h> #include <asm/scs.h> @@ -46,7 +47,7 @@ * a0 = &new_vmalloc[BIT_WORD(cpu)] * a1 = BIT_MASK(cpu) */ - REG_L a2, TASK_TI_CPU(tp) + lw a2, TASK_TI_CPU(tp) /* * Compute the new_vmalloc element position: * (cpu / 64) * 8 = (cpu >> 6) << 3 @@ -220,7 +221,7 @@ SYM_CODE_START_NOALIGN(ret_from_exception) #endif bnez s0, 1f -#ifdef CONFIG_GCC_PLUGIN_STACKLEAK +#ifdef CONFIG_KSTACK_ERASE call stackleak_erase_on_task_stack #endif @@ -319,17 +320,21 @@ SYM_CODE_END(handle_kernel_stack_overflow) ASM_NOKPROBE(handle_kernel_stack_overflow) #endif -SYM_CODE_START(ret_from_fork) +SYM_CODE_START(ret_from_fork_kernel_asm) + call schedule_tail + move a0, s1 /* fn_arg */ + move a1, s0 /* fn */ + move a2, sp /* pt_regs */ + call ret_from_fork_kernel + j ret_from_exception +SYM_CODE_END(ret_from_fork_kernel_asm) + +SYM_CODE_START(ret_from_fork_user_asm) call schedule_tail - beqz s0, 1f /* not from kernel thread */ - /* Call fn(arg) */ - move a0, s1 - jalr s0 -1: move a0, sp /* pt_regs */ - call syscall_exit_to_user_mode + call ret_from_fork_user j ret_from_exception -SYM_CODE_END(ret_from_fork) +SYM_CODE_END(ret_from_fork_user_asm) #ifdef CONFIG_IRQ_STACKS /* @@ -397,9 +402,18 @@ SYM_FUNC_START(__switch_to) REG_S s9, TASK_THREAD_S9_RA(a3) REG_S s10, TASK_THREAD_S10_RA(a3) REG_S s11, TASK_THREAD_S11_RA(a3) + + /* save the user space access flag */ + csrr s0, CSR_STATUS + REG_S s0, TASK_THREAD_SUM_RA(a3) + /* Save the kernel shadow call stack pointer */ scs_save_current /* Restore context from next->thread */ + REG_L s0, TASK_THREAD_SUM_RA(a4) + li s1, SR_SUM + and s0, s0, s1 + csrs CSR_STATUS, s0 REG_L ra, TASK_THREAD_RA_RA(a4) REG_L sp, TASK_THREAD_SP_RA(a4) REG_L s0, TASK_THREAD_S0_RA(a4) @@ -441,7 +455,7 @@ SYM_DATA_START_LOCAL(excp_vect_table) RISCV_PTR do_trap_ecall_s RISCV_PTR do_trap_unknown RISCV_PTR do_trap_ecall_m - /* instruciton page fault */ + /* instruction page fault */ ALT_PAGE_FAULT(RISCV_PTR do_page_fault) RISCV_PTR do_page_fault /* load page fault */ RISCV_PTR do_trap_unknown |