From 8801ccb9fa524c195322c26b6d44e99827772bde Mon Sep 17 00:00:00 2001 From: Helge Deller Date: Tue, 21 Aug 2018 14:31:32 +0200 Subject: parisc: Fix boot failure of 64-bit kernel Commit c8921d72e390 ("parisc: Fix and improve kernel stack unwinding") broke booting of 64-bit kernels. On 64-bit kernels function pointers are actually function descriptors which require dereferencing. In this patch we instead declare functions in assembly code which are referenced from C-code as external data pointers with the ENTRY() macro and thus can use a simple external reference to the functions. Signed-off-by: Helge Deller Fixes: c8921d72e390 ("parisc: Fix and improve kernel stack unwinding") --- arch/parisc/kernel/entry.S | 27 +++++++++++---------------- arch/parisc/kernel/unwind.c | 6 ++++-- 2 files changed, 15 insertions(+), 18 deletions(-) (limited to 'arch/parisc/kernel') diff --git a/arch/parisc/kernel/entry.S b/arch/parisc/kernel/entry.S index e170365941f8..242c5ab65611 100644 --- a/arch/parisc/kernel/entry.S +++ b/arch/parisc/kernel/entry.S @@ -777,7 +777,7 @@ END(fault_vector_11) * copy_thread moved args into task save area. */ -ENTRY_CFI(ret_from_kernel_thread) +ENTRY(ret_from_kernel_thread) /* Call schedule_tail first though */ BL schedule_tail, %r2 nop @@ -792,7 +792,7 @@ ENTRY_CFI(ret_from_kernel_thread) copy %r31, %r2 b finish_child_return nop -ENDPROC_CFI(ret_from_kernel_thread) +END(ret_from_kernel_thread) /* @@ -816,9 +816,8 @@ ENTRY_CFI(_switch_to) LDREG TASK_THREAD_INFO(%r25), %r25 bv %r0(%r2) mtctl %r25,%cr30 -ENDPROC_CFI(_switch_to) -ENTRY_CFI(_switch_to_ret) +ENTRY(_switch_to_ret) mtctl %r0, %cr0 /* Needed for single stepping */ callee_rest callee_rest_float @@ -826,7 +825,7 @@ ENTRY_CFI(_switch_to_ret) LDREG -RP_OFFSET(%r30), %r2 bv %r0(%r2) copy %r26, %r28 -ENDPROC_CFI(_switch_to_ret) +ENDPROC_CFI(_switch_to) /* * Common rfi return path for interruptions, kernel execve, and @@ -887,14 +886,12 @@ ENTRY_CFI(syscall_exit_rfi) STREG %r19,PT_SR5(%r16) STREG %r19,PT_SR6(%r16) STREG %r19,PT_SR7(%r16) -ENDPROC_CFI(syscall_exit_rfi) -ENTRY_CFI(intr_return) +ENTRY(intr_return) /* check for reschedule */ mfctl %cr30,%r1 LDREG TI_FLAGS(%r1),%r19 /* sched.h: TIF_NEED_RESCHED */ bb,<,n %r19,31-TIF_NEED_RESCHED,intr_do_resched /* forward */ -ENDPROC_CFI(intr_return) .import do_notify_resume,code intr_check_sig: @@ -1050,6 +1047,7 @@ intr_extint: b do_cpu_irq_mask ldo R%intr_return(%r2), %r2 /* return to intr_return, not here */ +ENDPROC_CFI(syscall_exit_rfi) /* Generic interruptions (illegal insn, unaligned, page fault, etc) */ @@ -1751,7 +1749,7 @@ fork_like fork fork_like vfork /* Set the return value for the child */ -ENTRY_CFI(child_return) +ENTRY(child_return) BL schedule_tail, %r2 nop finish_child_return: @@ -1763,7 +1761,7 @@ finish_child_return: reg_restore %r1 b syscall_exit copy %r0,%r28 -ENDPROC_CFI(child_return) +END(child_return) ENTRY_CFI(sys_rt_sigreturn_wrapper) LDREG TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r26 @@ -1795,7 +1793,7 @@ ENTRY_CFI(sys_rt_sigreturn_wrapper) LDREG PT_GR28(%r1),%r28 /* reload original r28 for syscall_exit */ ENDPROC_CFI(sys_rt_sigreturn_wrapper) -ENTRY_CFI(syscall_exit) +ENTRY(syscall_exit) /* NOTE: Not all syscalls exit this way. rt_sigreturn will exit * via syscall_exit_rfi if the signal was received while the process * was running. @@ -1994,15 +1992,13 @@ syscall_do_resched: #else nop #endif -ENDPROC_CFI(syscall_exit) +END(syscall_exit) #ifdef CONFIG_FUNCTION_TRACER .import ftrace_function_trampoline,code .align L1_CACHE_BYTES - .globl mcount - .type mcount, @function ENTRY_CFI(mcount, caller) _mcount: .export _mcount,data @@ -2031,8 +2027,6 @@ ENDPROC_CFI(mcount) #ifdef CONFIG_FUNCTION_GRAPH_TRACER .align 8 - .globl return_to_handler - .type return_to_handler, @function ENTRY_CFI(return_to_handler, caller,frame=FRAME_SIZE) .export parisc_return_to_handler,data parisc_return_to_handler: @@ -2082,6 +2076,7 @@ ENDPROC_CFI(return_to_handler) /* void call_on_stack(unsigned long param1, void *func, unsigned long new_stack) */ ENTRY_CFI(call_on_stack, FRAME=2*FRAME_SIZE,CALLS,SAVE_RP,SAVE_SP) +ENTRY(_call_on_stack) copy %sp, %r1 /* Regarding the HPPA calling conventions for function pointers, diff --git a/arch/parisc/kernel/unwind.c b/arch/parisc/kernel/unwind.c index 5578a325a730..f329b466e68f 100644 --- a/arch/parisc/kernel/unwind.c +++ b/arch/parisc/kernel/unwind.c @@ -209,6 +209,8 @@ static int unwind_special(struct unwind_frame_info *info, unsigned long pc, int * We have to use void * instead of a function pointer, because * function pointers aren't a pointer to the function on 64-bit. * Make them const so the compiler knows they live in .text + * Note: We could use dereference_kernel_function_descriptor() + * instead but we want to keep it simple here. */ extern void * const handle_interruption; extern void * const ret_from_kernel_thread; @@ -216,7 +218,7 @@ static int unwind_special(struct unwind_frame_info *info, unsigned long pc, int extern void * const intr_return; extern void * const _switch_to_ret; #ifdef CONFIG_IRQSTACKS - extern void * const call_on_stack; + extern void * const _call_on_stack; #endif /* CONFIG_IRQSTACKS */ if (pc == (unsigned long) &handle_interruption) { @@ -251,7 +253,7 @@ static int unwind_special(struct unwind_frame_info *info, unsigned long pc, int } #ifdef CONFIG_IRQSTACKS - if (pc == (unsigned long) &call_on_stack) { + if (pc == (unsigned long) &_call_on_stack) { info->prev_sp = *(unsigned long *)(info->sp - FRAME_SIZE - REG_SZ); info->prev_ip = *(unsigned long *)(info->sp - FRAME_SIZE - RP_OFFSET); return 1; -- cgit v1.2.3-59-g8ed1b