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-rw-r--r--arch/arc/kernel/entry.S127
1 files changed, 55 insertions, 72 deletions
diff --git a/arch/arc/kernel/entry.S b/arch/arc/kernel/entry.S
index 72be01270e24..089f6680518f 100644
--- a/arch/arc/kernel/entry.S
+++ b/arch/arc/kernel/entry.S
@@ -29,12 +29,24 @@ ENTRY(sys_clone_wrapper)
DISCARD_CALLEE_SAVED_USER
GET_CURR_THR_INFO_FLAGS r10
- btst r10, TIF_SYSCALL_TRACE
- bnz tracesys_exit
+ and.f 0, r10, _TIF_SYSCALL_WORK
+ bnz tracesys_exit
b .Lret_from_system_call
END(sys_clone_wrapper)
+ENTRY(sys_clone3_wrapper)
+ SAVE_CALLEE_SAVED_USER
+ bl @sys_clone3
+ DISCARD_CALLEE_SAVED_USER
+
+ GET_CURR_THR_INFO_FLAGS r10
+ and.f 0, r10, _TIF_SYSCALL_WORK
+ bnz tracesys_exit
+
+ b .Lret_from_system_call
+END(sys_clone3_wrapper)
+
ENTRY(ret_from_fork)
; when the forked child comes here from the __switch_to function
; r0 has the last task pointer.
@@ -68,11 +80,6 @@ ENTRY(instr_service)
EXCEPTION_PROLOGUE
- lr r0, [efa]
- mov r1, sp
-
- FAKE_RET_FROM_EXCPN
-
bl do_insterror_or_kprobe
b ret_from_exception
END(instr_service)
@@ -83,19 +90,15 @@ END(instr_service)
ENTRY(EV_MachineCheck)
- EXCEPTION_PROLOGUE
+ EXCEPTION_PROLOGUE_KEEP_AE ; ECR returned in r10
- lr r2, [ecr]
lr r0, [efa]
mov r1, sp
- ; hardware auto-disables MMU, re-enable it to allow kernel vaddr
- ; access for say stack unwinding of modules for crash dumps
- lr r3, [ARC_REG_PID]
- or r3, r3, MMU_ENABLE
- sr r3, [ARC_REG_PID]
+ ; MC excpetions disable MMU
+ ARC_MMU_REENABLE r3
- lsr r3, r2, 8
+ lsr r3, r10, 8
bmsk r3, r3, 7
brne r3, ECR_C_MCHK_DUP_TLB, 1f
@@ -120,11 +123,6 @@ ENTRY(EV_PrivilegeV)
EXCEPTION_PROLOGUE
- lr r0, [efa]
- mov r1, sp
-
- FAKE_RET_FROM_EXCPN
-
bl do_privilege_fault
b ret_from_exception
END(EV_PrivilegeV)
@@ -136,11 +134,6 @@ ENTRY(EV_Extension)
EXCEPTION_PROLOGUE
- lr r0, [efa]
- mov r1, sp
-
- FAKE_RET_FROM_EXCPN
-
bl do_extension_fault
b ret_from_exception
END(EV_Extension)
@@ -151,22 +144,20 @@ END(EV_Extension)
; syscall Tracing
; ---------------------------------------------
tracesys:
- ; save EFA in case tracer wants the PC of traced task
- ; using ERET won't work since next-PC has already committed
- lr r12, [efa]
+ ; safekeep EFA (r12) if syscall tracer wanted PC
+ ; for traps, ERET is pre-commit so points to next-PC
GET_CURR_TASK_FIELD_PTR TASK_THREAD, r11
st r12, [r11, THREAD_FAULT_ADDR] ; thread.fault_address
- ; PRE Sys Call Ptrace hook
- mov r0, sp ; pt_regs needed
- bl @syscall_trace_entry
+ ; PRE syscall trace hook
+ mov r0, sp ; pt_regs
+ bl @syscall_trace_enter
; Tracing code now returns the syscall num (orig or modif)
mov r8, r0
; Do the Sys Call as we normally would.
- ; Validate the Sys Call number
- cmp r8, NR_syscalls
+ cmp r8, NR_syscalls - 1
mov.hi r0, -ENOSYS
bhi tracesys_exit
@@ -182,42 +173,36 @@ tracesys:
ld r6, [sp, PT_r6]
ld r7, [sp, PT_r7]
ld.as r9, [sys_call_table, r8]
- jl [r9] ; Entry into Sys Call Handler
+ jl [r9]
tracesys_exit:
- st r0, [sp, PT_r0] ; sys call return value in pt_regs
+ st r0, [sp, PT_r0]
- ;POST Sys Call Ptrace Hook
+ ; POST syscall trace hook
+ mov r0, sp ; pt_regs needed
bl @syscall_trace_exit
- b ret_from_exception ; NOT ret_from_system_call at is saves r0 which
- ; we'd done before calling post hook above
+
+ ; don't call ret_from_system_call as it saves r0, already done above
+ b ret_from_exception
; ---------------------------------------------
; Breakpoint TRAP
; ---------------------------------------------
trap_with_param:
+ mov r0, r12 ; EFA in case ptracer/gdb wants stop_pc
+ mov r1, sp ; pt_regs
- ; stop_pc info by gdb needs this info
- lr r0, [efa]
- mov r1, sp
-
- ; Now that we have read EFA, it is safe to do "fake" rtie
- ; and get out of CPU exception mode
- FAKE_RET_FROM_EXCPN
-
- ; Save callee regs in case gdb wants to have a look
- ; SP will grow up by size of CALLEE Reg-File
- ; NOTE: clobbers r12
+ ; save callee regs in case tracer/gdb wants to peek
SAVE_CALLEE_SAVED_USER
- ; save location of saved Callee Regs @ thread_struct->pc
+ ; safekeep ref to callee regs
GET_CURR_TASK_FIELD_PTR TASK_THREAD, r10
st sp, [r10, THREAD_CALLEE_REG]
- ; Call the trap handler
+ ; call the non syscall trap handler
bl do_non_swi_trap
- ; unwind stack to discard Callee saved Regs
+ ; unwind stack to discard callee regs
DISCARD_CALLEE_SAVED_USER
b ret_from_exception
@@ -229,36 +214,33 @@ trap_with_param:
ENTRY(EV_Trap)
- EXCEPTION_PROLOGUE
+ EXCEPTION_PROLOGUE_KEEP_AE
+
+ lr r12, [efa]
+
+ FAKE_RET_FROM_EXCPN
- ;============ TRAP 1 :breakpoints
- ; Check ECR for trap with arg (PROLOGUE ensures r10 has ECR)
+ ;============ TRAP N : breakpoints, kprobes etc
bmsk.f 0, r10, 7
bnz trap_with_param
- ;============ TRAP (no param): syscall top level
-
- ; First return from Exception to pure K mode (Exception/IRQs renabled)
- FAKE_RET_FROM_EXCPN
+ ;============ TRAP 0 (no param): syscall
- ; If syscall tracing ongoing, invoke pre-post-hooks
+ ; syscall tracing ongoing, invoke pre-post-hooks around syscall
GET_CURR_THR_INFO_FLAGS r10
- btst r10, TIF_SYSCALL_TRACE
- bnz tracesys ; this never comes back
+ and.f 0, r10, _TIF_SYSCALL_WORK
+ bnz tracesys ; this never comes back
;============ Normal syscall case
- ; syscall num shd not exceed the total system calls avail
- cmp r8, NR_syscalls
+ cmp r8, NR_syscalls - 1
mov.hi r0, -ENOSYS
bhi .Lret_from_system_call
- ; Offset into the syscall_table and call handler
ld.as r9,[sys_call_table, r8]
- jl [r9] ; Entry into Sys Call Handler
+ jl [r9]
.Lret_from_system_call:
-
st r0, [sp, PT_r0] ; sys call return value in pt_regs
; fall through to ret_from_exception
@@ -301,7 +283,8 @@ resume_user_mode_begin:
mov r0, sp ; pt_regs for arg to do_signal()/do_notify_resume()
GET_CURR_THR_INFO_FLAGS r9
- bbit0 r9, TIF_SIGPENDING, .Lchk_notify_resume
+ and.f 0, r9, _TIF_SIGPENDING|_TIF_NOTIFY_SIGNAL
+ bz .Lchk_notify_resume
; Normal Trap/IRQ entry only saves Scratch (caller-saved) regs
; in pt_reg since the "C" ABI (kernel code) will automatically
@@ -313,7 +296,7 @@ resume_user_mode_begin:
; tracer might call PEEKUSR(CALLEE reg)
;
; NOTE: SP will grow up by size of CALLEE Reg-File
- SAVE_CALLEE_SAVED_USER ; clobbers r12
+ SAVE_CALLEE_SAVED_USER
; save location of saved Callee Regs @ thread_struct->callee
GET_CURR_TASK_FIELD_PTR TASK_THREAD, r10
@@ -337,11 +320,11 @@ resume_user_mode_begin:
resume_kernel_mode:
; Disable Interrupts from this point on
- ; CONFIG_PREEMPT: This is a must for preempt_schedule_irq()
- ; !CONFIG_PREEMPT: To ensure restore_regs is intr safe
+ ; CONFIG_PREEMPTION: This is a must for preempt_schedule_irq()
+ ; !CONFIG_PREEMPTION: To ensure restore_regs is intr safe
IRQ_DISABLE r9
-#ifdef CONFIG_PREEMPT
+#ifdef CONFIG_PREEMPTION
; Can't preempt if preemption disabled
GET_CURR_THR_INFO_FROM_SP r10
generated by cgit (git 2.34.1) at 2024-05-04 08:34:33 +0000