Re: [RFC PATCH v3 2/7] powerpc: Prepare for moving thread_info into task_struct
From: Nicholas Piggin
Date: Wed Oct 03 2018 - 01:58:09 EST
On Wed, 3 Oct 2018 07:49:44 +0200
Christophe LEROY <christophe.leroy@xxxxxx> wrote:
> Le 03/10/2018 Ã 07:02, Nicholas Piggin a ÃcritÂ:
> > On Mon, 1 Oct 2018 12:30:21 +0000 (UTC)
> > Christophe Leroy <christophe.leroy@xxxxxx> wrote:
> >
> >> This patch cleans the powerpc kernel before activating
> >> CONFIG_THREAD_INFO_IN_TASK:
> >> - The purpose of the pointer given to call_do_softirq() and
> >> call_do_irq() is to point the new stack ==> change it to void*
> >> - Don't use CURRENT_THREAD_INFO() to locate the stack.
> >> - Fixed a few comments.
> >> - TI_CPU is only used when CONFIG_SMP is set.
> >> - Replace current_thread_info()->task by current
> >> - Remove unnecessary casts to thread_info, as they'll become invalid
> >> once thread_info is not in stack anymore.
> >> - Ensure task_struct 'cpu' fields is not used directly out of SMP code
> >> - Rename THREAD_INFO to TASK_STASK: As it is in fact the offset of the
> >> pointer to the stack in task_struct, this pointer will not be impacted
> >> by the move of THREAD_INFO.
> >> - Makes TASK_STACK available to PPC64 which will need it to the get
> >> stack pointer from current once the thread_info have been moved.
> >>
> >> Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx>
> >> ---
> >> arch/powerpc/include/asm/irq.h | 4 ++--
> >> arch/powerpc/include/asm/livepatch.h | 2 +-
> >> arch/powerpc/include/asm/processor.h | 4 ++--
> >> arch/powerpc/include/asm/reg.h | 2 +-
> >> arch/powerpc/kernel/asm-offsets.c | 2 +-
> >> arch/powerpc/kernel/entry_32.S | 2 +-
> >> arch/powerpc/kernel/entry_64.S | 2 +-
> >> arch/powerpc/kernel/head_32.S | 4 ++--
> >> arch/powerpc/kernel/head_40x.S | 4 ++--
> >> arch/powerpc/kernel/head_44x.S | 2 +-
> >> arch/powerpc/kernel/head_8xx.S | 2 +-
> >> arch/powerpc/kernel/head_booke.h | 4 ++--
> >> arch/powerpc/kernel/head_fsl_booke.S | 6 ++++--
> >> arch/powerpc/kernel/irq.c | 2 +-
> >> arch/powerpc/kernel/misc_32.S | 8 ++++++--
> >> arch/powerpc/kernel/process.c | 6 +++---
> >> arch/powerpc/kernel/setup_32.c | 15 +++++----------
> >> arch/powerpc/kernel/smp.c | 4 +++-
> >> arch/powerpc/xmon/xmon.c | 2 +-
> >> 19 files changed, 40 insertions(+), 37 deletions(-)
> >>
> >> diff --git a/arch/powerpc/include/asm/irq.h b/arch/powerpc/include/asm/irq.h
> >> index ee39ce56b2a2..8108d1fe33ca 100644
> >> --- a/arch/powerpc/include/asm/irq.h
> >> +++ b/arch/powerpc/include/asm/irq.h
> >> @@ -63,8 +63,8 @@ extern struct thread_info *hardirq_ctx[NR_CPUS];
> >> extern struct thread_info *softirq_ctx[NR_CPUS];
> >>
> >> extern void irq_ctx_init(void);
> >> -extern void call_do_softirq(struct thread_info *tp);
> >> -extern void call_do_irq(struct pt_regs *regs, struct thread_info *tp);
> >> +extern void call_do_softirq(void *tp);
> >> +extern void call_do_irq(struct pt_regs *regs, void *tp);
> >
> > void *sp for these ?
>
> Yes, why not but it means changing the code. I wanted to minimise the
> changes and avoid cosmetic.
Fair enough.
> Or maybe should add a cosmetic patch at the
> end ?
Yeah that would be nice, I don't mind too much if it goes as part of
the patches or as a cleanup afterward. There's a few other places that
could use similar minor.
> > This all seems okay to me except the 32-bit code which I don't know.
> > Would it be any trouble for you to put the TI_CPU bits into their own
> > patch?
>
> No problem, I can put the TI_CPU bits in a separate patch.
Great thanks.
Thanks,
Nick
>
> >
> > Reviewed-by: Nicholas Piggin <npiggin@xxxxxxxxx>
> >
>
> Thanks
> Christophe
>
> >
> >> extern void do_IRQ(struct pt_regs *regs);
> >> extern void __init init_IRQ(void);
> >> extern void __do_irq(struct pt_regs *regs);
> >> diff --git a/arch/powerpc/include/asm/livepatch.h b/arch/powerpc/include/asm/livepatch.h
> >> index 47a03b9b528b..818451bf629c 100644
> >> --- a/arch/powerpc/include/asm/livepatch.h
> >> +++ b/arch/powerpc/include/asm/livepatch.h
> >> @@ -49,7 +49,7 @@ static inline void klp_init_thread_info(struct thread_info *ti)
> >> ti->livepatch_sp = (unsigned long *)(ti + 1) + 1;
> >> }
> >> #else
> >> -static void klp_init_thread_info(struct thread_info *ti) { }
> >> +static inline void klp_init_thread_info(struct thread_info *ti) { }
> >> #endif /* CONFIG_LIVEPATCH */
> >>
> >> #endif /* _ASM_POWERPC_LIVEPATCH_H */
> >> diff --git a/arch/powerpc/include/asm/processor.h b/arch/powerpc/include/asm/processor.h
> >> index 353879db3e98..31873614392f 100644
> >> --- a/arch/powerpc/include/asm/processor.h
> >> +++ b/arch/powerpc/include/asm/processor.h
> >> @@ -40,7 +40,7 @@
> >>
> >> #ifndef __ASSEMBLY__
> >> #include <linux/types.h>
> >> -#include <asm/thread_info.h>
> >> +#include <linux/thread_info.h>
> >> #include <asm/ptrace.h>
> >> #include <asm/hw_breakpoint.h>
> >>
> >> @@ -333,7 +333,7 @@ struct thread_struct {
> >>
> >> #define INIT_SP (sizeof(init_stack) + (unsigned long) &init_stack)
> >> #define INIT_SP_LIMIT \
> >> - (_ALIGN_UP(sizeof(init_thread_info), 16) + (unsigned long) &init_stack)
> >> + (_ALIGN_UP(sizeof(struct thread_info), 16) + (unsigned long) &init_stack)
> >>
> >> #ifdef CONFIG_SPE
> >> #define SPEFSCR_INIT \
> >> diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
> >> index e5b314ed054e..f3a9cf19a986 100644
> >> --- a/arch/powerpc/include/asm/reg.h
> >> +++ b/arch/powerpc/include/asm/reg.h
> >> @@ -1053,7 +1053,7 @@
> >> * - SPRG9 debug exception scratch
> >> *
> >> * All 32-bit:
> >> - * - SPRG3 current thread_info pointer
> >> + * - SPRG3 current thread_struct physical addr pointer
> >> * (virtual on BookE, physical on others)
> >> *
> >> * 32-bit classic:
> >> diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
> >> index ba9d0fc98730..d1f161e48945 100644
> >> --- a/arch/powerpc/kernel/asm-offsets.c
> >> +++ b/arch/powerpc/kernel/asm-offsets.c
> >> @@ -85,10 +85,10 @@ int main(void)
> >> DEFINE(NMI_MASK, NMI_MASK);
> >> OFFSET(TASKTHREADPPR, task_struct, thread.ppr);
> >> #else
> >> - OFFSET(THREAD_INFO, task_struct, stack);
> >> DEFINE(THREAD_INFO_GAP, _ALIGN_UP(sizeof(struct thread_info), 16));
> >> OFFSET(KSP_LIMIT, thread_struct, ksp_limit);
> >> #endif /* CONFIG_PPC64 */
> >> + OFFSET(TASK_STACK, task_struct, stack);
> >>
> >> #ifdef CONFIG_LIVEPATCH
> >> OFFSET(TI_livepatch_sp, thread_info, livepatch_sp);
> >> diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
> >> index e58c3f467db5..12c0721f65ea 100644
> >> --- a/arch/powerpc/kernel/entry_32.S
> >> +++ b/arch/powerpc/kernel/entry_32.S
> >> @@ -1166,7 +1166,7 @@ ret_from_debug_exc:
> >> mfspr r9,SPRN_SPRG_THREAD
> >> lwz r10,SAVED_KSP_LIMIT(r1)
> >> stw r10,KSP_LIMIT(r9)
> >> - lwz r9,THREAD_INFO-THREAD(r9)
> >> + lwz r9,TASK_STACK-THREAD(r9)
> >> CURRENT_THREAD_INFO(r10, r1)
> >> lwz r10,TI_PREEMPT(r10)
> >> stw r10,TI_PREEMPT(r9)
> >> diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
> >> index 77a888bfcb53..697406572592 100644
> >> --- a/arch/powerpc/kernel/entry_64.S
> >> +++ b/arch/powerpc/kernel/entry_64.S
> >> @@ -680,7 +680,7 @@ END_FTR_SECTION_IFCLR(CPU_FTR_ARCH_207S)
> >> 2:
> >> #endif /* CONFIG_PPC_BOOK3S_64 */
> >>
> >> - CURRENT_THREAD_INFO(r7, r8) /* base of new stack */
> >> + clrrdi r7, r8, THREAD_SHIFT /* base of new stack */
> >> /* Note: this uses SWITCH_FRAME_SIZE rather than INT_FRAME_SIZE
> >> because we don't need to leave the 288-byte ABI gap at the
> >> top of the kernel stack. */
> >> diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S
> >> index 61ca27929355..dce6f2ff07e5 100644
> >> --- a/arch/powerpc/kernel/head_32.S
> >> +++ b/arch/powerpc/kernel/head_32.S
> >> @@ -261,7 +261,7 @@ __secondary_hold_acknowledge:
> >> tophys(r11,r1); /* use tophys(r1) if kernel */ \
> >> beq 1f; \
> >> mfspr r11,SPRN_SPRG_THREAD; \
> >> - lwz r11,THREAD_INFO-THREAD(r11); \
> >> + lwz r11,TASK_STACK-THREAD(r11); \
> >> addi r11,r11,THREAD_SIZE; \
> >> tophys(r11,r11); \
> >> 1: subi r11,r11,INT_FRAME_SIZE /* alloc exc. frame */
> >> @@ -841,7 +841,7 @@ __secondary_start:
> >> bl init_idle_6xx
> >> #endif /* CONFIG_6xx */
> >>
> >> - /* get current_thread_info and current */
> >> + /* get current's stack and current */
> >> lis r1,secondary_ti@ha
> >> tophys(r1,r1)
> >> lwz r1,secondary_ti@l(r1)
> >> diff --git a/arch/powerpc/kernel/head_40x.S b/arch/powerpc/kernel/head_40x.S
> >> index b19d78410511..3088c9f29f5e 100644
> >> --- a/arch/powerpc/kernel/head_40x.S
> >> +++ b/arch/powerpc/kernel/head_40x.S
> >> @@ -115,7 +115,7 @@ _ENTRY(saved_ksp_limit)
> >> andi. r11,r11,MSR_PR; \
> >> beq 1f; \
> >> mfspr r1,SPRN_SPRG_THREAD; /* if from user, start at top of */\
> >> - lwz r1,THREAD_INFO-THREAD(r1); /* this thread's kernel stack */\
> >> + lwz r1,TASK_STACK-THREAD(r1); /* this thread's kernel stack */\
> >> addi r1,r1,THREAD_SIZE; \
> >> 1: subi r1,r1,INT_FRAME_SIZE; /* Allocate an exception frame */\
> >> tophys(r11,r1); \
> >> @@ -158,7 +158,7 @@ _ENTRY(saved_ksp_limit)
> >> beq 1f; \
> >> /* COMING FROM USER MODE */ \
> >> mfspr r11,SPRN_SPRG_THREAD; /* if from user, start at top of */\
> >> - lwz r11,THREAD_INFO-THREAD(r11); /* this thread's kernel stack */\
> >> + lwz r11,TASK_STACK-THREAD(r11); /* this thread's kernel stack */\
> >> 1: addi r11,r11,THREAD_SIZE-INT_FRAME_SIZE; /* Alloc an excpt frm */\
> >> tophys(r11,r11); \
> >> stw r10,_CCR(r11); /* save various registers */\
> >> diff --git a/arch/powerpc/kernel/head_44x.S b/arch/powerpc/kernel/head_44x.S
> >> index 37e4a7cf0065..15d39b2499de 100644
> >> --- a/arch/powerpc/kernel/head_44x.S
> >> +++ b/arch/powerpc/kernel/head_44x.S
> >> @@ -1020,7 +1020,7 @@ _GLOBAL(start_secondary_47x)
> >>
> >> /* Now we can get our task struct and real stack pointer */
> >>
> >> - /* Get current_thread_info and current */
> >> + /* Get current's stack and current */
> >> lis r1,secondary_ti@ha
> >> lwz r1,secondary_ti@l(r1)
> >> lwz r2,TI_TASK(r1)
> >> diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
> >> index 6582f824d620..e56e36aa2b3d 100644
> >> --- a/arch/powerpc/kernel/head_8xx.S
> >> +++ b/arch/powerpc/kernel/head_8xx.S
> >> @@ -124,7 +124,7 @@ turn_on_mmu:
> >> tophys(r11,r1); /* use tophys(r1) if kernel */ \
> >> beq 1f; \
> >> mfspr r11,SPRN_SPRG_THREAD; \
> >> - lwz r11,THREAD_INFO-THREAD(r11); \
> >> + lwz r11,TASK_STACK-THREAD(r11); \
> >> addi r11,r11,THREAD_SIZE; \
> >> tophys(r11,r11); \
> >> 1: subi r11,r11,INT_FRAME_SIZE /* alloc exc. frame */
> >> diff --git a/arch/powerpc/kernel/head_booke.h b/arch/powerpc/kernel/head_booke.h
> >> index d0862a100d29..20fe0c93a0bd 100644
> >> --- a/arch/powerpc/kernel/head_booke.h
> >> +++ b/arch/powerpc/kernel/head_booke.h
> >> @@ -44,7 +44,7 @@
> >> mr r11, r1; \
> >> beq 1f; \
> >> /* if from user, start at top of this thread's kernel stack */ \
> >> - lwz r11, THREAD_INFO-THREAD(r10); \
> >> + lwz r11, TASK_STACK-THREAD(r10); \
> >> ALLOC_STACK_FRAME(r11, THREAD_SIZE); \
> >> 1 : subi r11, r11, INT_FRAME_SIZE; /* Allocate exception frame */ \
> >> stw r13, _CCR(r11); /* save various registers */ \
> >> @@ -130,7 +130,7 @@
> >> DO_KVM BOOKE_INTERRUPT_##intno exc_level_srr1; \
> >> andi. r11,r11,MSR_PR; \
> >> mfspr r11,SPRN_SPRG_THREAD; /* if from user, start at top of */\
> >> - lwz r11,THREAD_INFO-THREAD(r11); /* this thread's kernel stack */\
> >> + lwz r11,TASK_STACK-THREAD(r11); /* this thread's kernel stack */\
> >> addi r11,r11,EXC_LVL_FRAME_OVERHEAD; /* allocate stack frame */\
> >> beq 1f; \
> >> /* COMING FROM USER MODE */ \
> >> diff --git a/arch/powerpc/kernel/head_fsl_booke.S b/arch/powerpc/kernel/head_fsl_booke.S
> >> index e2750b856c8f..239ad8a4754e 100644
> >> --- a/arch/powerpc/kernel/head_fsl_booke.S
> >> +++ b/arch/powerpc/kernel/head_fsl_booke.S
> >> @@ -243,8 +243,10 @@ set_ivor:
> >> li r0,0
> >> stwu r0,THREAD_SIZE-STACK_FRAME_OVERHEAD(r1)
> >>
> >> +#ifdef CONFIG_SMP
> >> CURRENT_THREAD_INFO(r22, r1)
> >> stw r24, TI_CPU(r22)
> >> +#endif
> >>
> >> bl early_init
> >>
> >> @@ -702,7 +704,7 @@ finish_tlb_load:
> >>
> >> /* Get the next_tlbcam_idx percpu var */
> >> #ifdef CONFIG_SMP
> >> - lwz r12, THREAD_INFO-THREAD(r12)
> >> + lwz r12, TASK_STACK-THREAD(r12)
> >> lwz r15, TI_CPU(r12)
> >> lis r14, __per_cpu_offset@h
> >> ori r14, r14, __per_cpu_offset@l
> >> @@ -1074,7 +1076,7 @@ __secondary_start:
> >> mr r4,r24 /* Why? */
> >> bl call_setup_cpu
> >>
> >> - /* get current_thread_info and current */
> >> + /* get current's stack and current */
> >> lis r1,secondary_ti@ha
> >> lwz r1,secondary_ti@l(r1)
> >> lwz r2,TI_TASK(r1)
> >> diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c
> >> index 916ddc4aac44..aa53db3ba6e7 100644
> >> --- a/arch/powerpc/kernel/irq.c
> >> +++ b/arch/powerpc/kernel/irq.c
> >> @@ -663,7 +663,7 @@ void do_IRQ(struct pt_regs *regs)
> >> struct thread_info *curtp, *irqtp, *sirqtp;
> >>
> >> /* Switch to the irq stack to handle this */
> >> - curtp = current_thread_info();
> >> + curtp = (void*)(current_stack_pointer() & ~(THREAD_SIZE - 1));
> >> irqtp = hardirq_ctx[raw_smp_processor_id()];
> >> sirqtp = softirq_ctx[raw_smp_processor_id()];
> >>
> >> diff --git a/arch/powerpc/kernel/misc_32.S b/arch/powerpc/kernel/misc_32.S
> >> index 695b24a2d954..24a7f18ea10c 100644
> >> --- a/arch/powerpc/kernel/misc_32.S
> >> +++ b/arch/powerpc/kernel/misc_32.S
> >> @@ -60,7 +60,7 @@ _GLOBAL(call_do_softirq)
> >> blr
> >>
> >> /*
> >> - * void call_do_irq(struct pt_regs *regs, struct thread_info *irqtp);
> >> + * void call_do_irq(struct pt_regs *regs, void *irqtp);
> >> */
> >> _GLOBAL(call_do_irq)
> >> mflr r0
> >> @@ -183,10 +183,14 @@ _GLOBAL(low_choose_750fx_pll)
> >> or r4,r4,r5
> >> mtspr SPRN_HID1,r4
> >>
> >> +#ifdef CONFIG_SMP
> >> /* Store new HID1 image */
> >> CURRENT_THREAD_INFO(r6, r1)
> >> lwz r6,TI_CPU(r6)
> >> slwi r6,r6,2
> >> +#else
> >> + li r6, 0
> >> +#endif
> >> addis r6,r6,nap_save_hid1@ha
> >> stw r4,nap_save_hid1@l(r6)
> >>
> >> @@ -599,7 +603,7 @@ EXPORT_SYMBOL(__bswapdi2)
> >> #ifdef CONFIG_SMP
> >> _GLOBAL(start_secondary_resume)
> >> /* Reset stack */
> >> - CURRENT_THREAD_INFO(r1, r1)
> >> + rlwinm r1, r1, 0, 0, 31 - THREAD_SHIFT
> >> addi r1,r1,THREAD_SIZE-STACK_FRAME_OVERHEAD
> >> li r3,0
> >> stw r3,0(r1) /* Zero the stack frame pointer */
> >> diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
> >> index 03c2e1f134bc..111abb4df2ec 100644
> >> --- a/arch/powerpc/kernel/process.c
> >> +++ b/arch/powerpc/kernel/process.c
> >> @@ -1240,8 +1240,8 @@ struct task_struct *__switch_to(struct task_struct *prev,
> >> batch->active = 1;
> >> }
> >>
> >> - if (current_thread_info()->task->thread.regs) {
> >> - restore_math(current_thread_info()->task->thread.regs);
> >> + if (current->thread.regs) {
> >> + restore_math(current->thread.regs);
> >>
> >> /*
> >> * The copy-paste buffer can only store into foreign real
> >> @@ -1251,7 +1251,7 @@ struct task_struct *__switch_to(struct task_struct *prev,
> >> * mappings, we must issue a cp_abort to clear any state and
> >> * prevent snooping, corruption or a covert channel.
> >> */
> >> - if (current_thread_info()->task->thread.used_vas)
> >> + if (current->thread.used_vas)
> >> asm volatile(PPC_CP_ABORT);
> >> }
> >> #endif /* CONFIG_PPC_BOOK3S_64 */
> >> diff --git a/arch/powerpc/kernel/setup_32.c b/arch/powerpc/kernel/setup_32.c
> >> index 8c507be12c3c..81ebf7d6f526 100644
> >> --- a/arch/powerpc/kernel/setup_32.c
> >> +++ b/arch/powerpc/kernel/setup_32.c
> >> @@ -205,10 +205,8 @@ void __init irqstack_early_init(void)
> >> /* interrupt stacks must be in lowmem, we get that for free on ppc32
> >> * as the memblock is limited to lowmem by default */
> >> for_each_possible_cpu(i) {
> >> - softirq_ctx[i] = (struct thread_info *)
> >> - __va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
> >> - hardirq_ctx[i] = (struct thread_info *)
> >> - __va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
> >> + softirq_ctx[i] = __va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
> >> + hardirq_ctx[i] = __va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
> >> }
> >> }
> >>
> >> @@ -226,13 +224,10 @@ void __init exc_lvl_early_init(void)
> >> hw_cpu = 0;
> >> #endif
> >>
> >> - critirq_ctx[hw_cpu] = (struct thread_info *)
> >> - __va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
> >> + critirq_ctx[hw_cpu] = __va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
> >> #ifdef CONFIG_BOOKE
> >> - dbgirq_ctx[hw_cpu] = (struct thread_info *)
> >> - __va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
> >> - mcheckirq_ctx[hw_cpu] = (struct thread_info *)
> >> - __va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
> >> + dbgirq_ctx[hw_cpu] = __va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
> >> + mcheckirq_ctx[hw_cpu] = __va(memblock_alloc(THREAD_SIZE, THREAD_SIZE));
> >> #endif
> >> }
> >> }
> >> diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
> >> index 61c1fadbc644..19dd0ea55714 100644
> >> --- a/arch/powerpc/kernel/smp.c
> >> +++ b/arch/powerpc/kernel/smp.c
> >> @@ -20,6 +20,7 @@
> >> #include <linux/kernel.h>
> >> #include <linux/export.h>
> >> #include <linux/sched/mm.h>
> >> +#include <linux/sched/task_stack.h>
> >> #include <linux/sched/topology.h>
> >> #include <linux/smp.h>
> >> #include <linux/interrupt.h>
> >> @@ -812,7 +813,8 @@ static void cpu_idle_thread_init(unsigned int cpu, struct task_struct *idle)
> >>
> >> #ifdef CONFIG_PPC64
> >> paca_ptrs[cpu]->__current = idle;
> >> - paca_ptrs[cpu]->kstack = (unsigned long)ti + THREAD_SIZE - STACK_FRAME_OVERHEAD;
> >> + paca_ptrs[cpu]->kstack = (unsigned long)task_stack_page(idle) +
> >> + THREAD_SIZE - STACK_FRAME_OVERHEAD;
> >> #endif
> >> ti->cpu = cpu;
> >> secondary_ti = current_set[cpu] = ti;
> >> diff --git a/arch/powerpc/xmon/xmon.c b/arch/powerpc/xmon/xmon.c
> >> index 694c1d92e796..0d8d6fee892a 100644
> >> --- a/arch/powerpc/xmon/xmon.c
> >> +++ b/arch/powerpc/xmon/xmon.c
> >> @@ -2988,7 +2988,7 @@ static void show_task(struct task_struct *tsk)
> >> printf("%px %016lx %6d %6d %c %2d %s\n", tsk,
> >> tsk->thread.ksp,
> >> tsk->pid, tsk->parent->pid,
> >> - state, task_thread_info(tsk)->cpu,
> >> + state, task_cpu(tsk),
> >> tsk->comm);
> >> }
> >>
> >> --
> >> 2.13.3
> >>