diff options
Diffstat (limited to 'arch/arm64/kernel/entry.S')
| -rw-r--r-- | arch/arm64/kernel/entry.S | 85 |
1 files changed, 69 insertions, 16 deletions
diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index a8e4bdbbb4b8..3e6f4dc5e61e 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -30,6 +30,32 @@ #include <asm/unistd32.h> /* + * Context tracking subsystem. Used to instrument transitions + * between user and kernel mode. + */ + .macro ct_user_exit, syscall = 0 +#ifdef CONFIG_CONTEXT_TRACKING + bl context_tracking_user_exit + .if \syscall == 1 + /* + * Save/restore needed during syscalls. Restore syscall arguments from + * the values already saved on stack during kernel_entry. + */ + ldp x0, x1, [sp] + ldp x2, x3, [sp, #S_X2] + ldp x4, x5, [sp, #S_X4] + ldp x6, x7, [sp, #S_X6] + .endif +#endif + .endm + + .macro ct_user_enter +#ifdef CONFIG_CONTEXT_TRACKING + bl context_tracking_user_enter +#endif + .endm + +/* * Bad Abort numbers *----------------- */ @@ -88,7 +114,19 @@ .macro kernel_exit, el, ret = 0 ldp x21, x22, [sp, #S_PC] // load ELR, SPSR .if \el == 0 + ct_user_enter ldr x23, [sp, #S_SP] // load return stack pointer +#ifdef CONFIG_ARM64_ERRATUM_845719 + tbz x22, #4, 1f +#ifdef CONFIG_PID_IN_CONTEXTIDR + mrs x29, contextidr_el1 + msr contextidr_el1, x29 +1: +#else + msr contextidr_el1, xzr +1: +#endif +#endif .endif .if \ret ldr x1, [sp, #S_X1] // preserve x0 (syscall return) @@ -348,7 +386,6 @@ el0_sync: lsr x24, x25, #ESR_EL1_EC_SHIFT // exception class cmp x24, #ESR_EL1_EC_SVC64 // SVC in 64-bit state b.eq el0_svc - adr lr, ret_from_exception cmp x24, #ESR_EL1_EC_DABT_EL0 // data abort in EL0 b.eq el0_da cmp x24, #ESR_EL1_EC_IABT_EL0 // instruction abort in EL0 @@ -377,7 +414,6 @@ el0_sync_compat: lsr x24, x25, #ESR_EL1_EC_SHIFT // exception class cmp x24, #ESR_EL1_EC_SVC32 // SVC in 32-bit state b.eq el0_svc_compat - adr lr, ret_from_exception cmp x24, #ESR_EL1_EC_DABT_EL0 // data abort in EL0 b.eq el0_da cmp x24, #ESR_EL1_EC_IABT_EL0 // instruction abort in EL0 @@ -420,78 +456,94 @@ el0_da: /* * Data abort handling */ - mrs x0, far_el1 - bic x0, x0, #(0xff << 56) + mrs x26, far_el1 disable_step x1 isb enable_dbg // enable interrupts before calling the main handler enable_irq + ct_user_exit + bic x0, x26, #(0xff << 56) mov x1, x25 mov x2, sp + adr lr, ret_from_exception b do_mem_abort el0_ia: /* * Instruction abort handling */ - mrs x0, far_el1 + mrs x26, far_el1 disable_step x1 isb enable_dbg // enable interrupts before calling the main handler enable_irq + ct_user_exit + mov x0, x26 orr x1, x25, #1 << 24 // use reserved ISS bit for instruction aborts mov x2, sp + adr lr, ret_from_exception b do_mem_abort el0_fpsimd_acc: /* * Floating Point or Advanced SIMD access */ + ct_user_exit mov x0, x25 mov x1, sp + adr lr, ret_from_exception b do_fpsimd_acc el0_fpsimd_exc: /* * Floating Point or Advanced SIMD exception */ + ct_user_exit mov x0, x25 mov x1, sp + adr lr, ret_from_exception b do_fpsimd_exc el0_sp_pc: /* * Stack or PC alignment exception handling */ - mrs x0, far_el1 + mrs x26, far_el1 disable_step x1 isb enable_dbg // enable interrupts before calling the main handler enable_irq + mov x0, x26 mov x1, x25 mov x2, sp + adr lr, ret_from_exception b do_sp_pc_abort el0_undef: /* * Undefined instruction */ - mov x0, sp // enable interrupts before calling the main handler + ct_user_exit enable_irq + mov x0, sp + adr lr, ret_from_exception b do_undefinstr el0_dbg: /* * Debug exception handling */ tbnz x24, #0, el0_inv // EL0 only + ct_user_exit mrs x0, far_el1 disable_step x1 mov x1, x25 mov x2, sp b do_debug_exception el0_inv: + ct_user_exit mov x0, sp mov x1, #BAD_SYNC mrs x2, esr_el1 + adr lr, ret_from_exception b bad_mode ENDPROC(el0_sync) @@ -506,6 +558,7 @@ el0_irq_naked: bl trace_hardirqs_off #endif + ct_user_exit irq_handler get_thread_info tsk @@ -575,7 +628,7 @@ fast_work_pending: str x0, [sp, #S_X0] // returned x0 work_pending: tbnz x1, #TIF_NEED_RESCHED, work_resched - /* TIF_SIGPENDING or TIF_NOTIFY_RESUME case */ + /* TIF_SIGPENDING, TIF_NOTIFY_RESUME or TIF_FOREIGN_FPSTATE case */ ldr x2, [sp, #S_PSTATE] mov x0, sp // 'regs' tst x2, #PSR_MODE_MASK // user mode regs? @@ -628,10 +681,12 @@ el0_svc_naked: // compat entry point isb enable_dbg enable_irq + ct_user_exit 1 get_thread_info tsk - ldr x16, [tsk, #TI_FLAGS] // check for syscall tracing - tbnz x16, #TIF_SYSCALL_TRACE, __sys_trace // are we tracing syscalls? + ldr x16, [tsk, #TI_FLAGS] // check for syscall hooks + tst x16, #_TIF_SYSCALL_WORK + b.ne __sys_trace adr lr, ret_fast_syscall // return address cmp scno, sc_nr // check upper syscall limit b.hs ni_sys @@ -647,9 +702,8 @@ ENDPROC(el0_svc) * switches, and waiting for our parent to respond. */ __sys_trace: - mov x1, sp - mov w0, #0 // trace entry - bl syscall_trace + mov x0, sp + bl syscall_trace_enter adr lr, __sys_trace_return // return address uxtw scno, w0 // syscall number (possibly new) mov x1, sp // pointer to regs @@ -664,9 +718,8 @@ __sys_trace: __sys_trace_return: str x0, [sp] // save returned x0 - mov x1, sp - mov w0, #1 // trace exit - bl syscall_trace + mov x0, sp + bl syscall_trace_exit b ret_to_user /* |