Commit cbc9565ee826 ("powerpc: Remove ksp_limit on ppc64") moved PPC32 ksp_limit handling in assembly functions call_do_softirq() and call_do_irq() as they are different for PPC32 and PPC64.
In preparation of replacing these functions by inline assembly, partialy revert that commit to bring back ksp_limit assignment in the callers. To get and set ksp_limit without a forest of #ifdefs CONFIG_PPC32, use helpers that will void on PPC64. Signed-off-by: Christophe Leroy <christophe.le...@c-s.fr> --- arch/powerpc/include/asm/irq.h | 21 +++++++++++++++++++++ arch/powerpc/kernel/irq.c | 14 +++++++++++++- arch/powerpc/kernel/misc_32.S | 14 -------------- 3 files changed, 34 insertions(+), 15 deletions(-) diff --git a/arch/powerpc/include/asm/irq.h b/arch/powerpc/include/asm/irq.h index 814dfab7e392..52adec9a379d 100644 --- a/arch/powerpc/include/asm/irq.h +++ b/arch/powerpc/include/asm/irq.h @@ -64,5 +64,26 @@ extern void __do_irq(struct pt_regs *regs); int irq_choose_cpu(const struct cpumask *mask); +#ifdef CONFIG_PPC32 +static inline unsigned long get_ksp_limit(struct task_struct *tsk) +{ + return tsk->thread.ksp_limit; +} + +static inline void set_ksp_limit(struct task_struct *tsk, unsigned long limit) +{ + tsk->thread.ksp_limit = limit; +} +#else +static inline unsigned long get_ksp_limit(struct task_struct *tsk) +{ + return 0; +} + +static inline void set_ksp_limit(struct task_struct *tsk, unsigned long limit) +{ +} +#endif + #endif /* _ASM_IRQ_H */ #endif /* __KERNEL__ */ diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c index 5645bc9cbc09..04204be49577 100644 --- a/arch/powerpc/kernel/irq.c +++ b/arch/powerpc/kernel/irq.c @@ -646,6 +646,7 @@ void do_IRQ(struct pt_regs *regs) { struct pt_regs *old_regs = set_irq_regs(regs); void *cursp, *irqsp, *sirqsp; + unsigned long saved_ksp_limit = get_ksp_limit(current); /* Switch to the irq stack to handle this */ cursp = (void *)(current_stack_pointer() & ~(THREAD_SIZE - 1)); @@ -658,9 +659,15 @@ void do_IRQ(struct pt_regs *regs) set_irq_regs(old_regs); return; } + /* Adjust the stack limit */ + set_ksp_limit(current, (unsigned long)irqsp); + /* Switch stack and call */ call_do_irq(regs, irqsp); + /* Restore stack limit */ + set_ksp_limit(current, saved_ksp_limit); + set_irq_regs(old_regs); } @@ -681,7 +688,12 @@ void *hardirq_ctx[NR_CPUS] __read_mostly; void do_softirq_own_stack(void) { - call_do_softirq(softirq_ctx[smp_processor_id()]); + void *irqsp = softirq_ctx[smp_processor_id()]; + unsigned long saved_ksp_limit = get_ksp_limit(current); + + set_ksp_limit(current, (unsigned long)irqsp); + call_do_softirq(irqsp); + set_ksp_limit(current, saved_ksp_limit); } irq_hw_number_t virq_to_hw(unsigned int virq) diff --git a/arch/powerpc/kernel/misc_32.S b/arch/powerpc/kernel/misc_32.S index 82df4b09e79f..a5422f7782b3 100644 --- a/arch/powerpc/kernel/misc_32.S +++ b/arch/powerpc/kernel/misc_32.S @@ -33,23 +33,14 @@ .text -/* - * We store the saved ksp_limit in the unused part - * of the STACK_FRAME_OVERHEAD - */ _GLOBAL(call_do_softirq) mflr r0 stw r0,4(r1) - lwz r10,THREAD+KSP_LIMIT(r2) - stw r3, THREAD+KSP_LIMIT(r2) stwu r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r3) mr r1,r3 - stw r10,8(r1) bl __do_softirq - lwz r10,8(r1) lwz r1,0(r1) lwz r0,4(r1) - stw r10,THREAD+KSP_LIMIT(r2) mtlr r0 blr @@ -59,16 +50,11 @@ _GLOBAL(call_do_softirq) _GLOBAL(call_do_irq) mflr r0 stw r0,4(r1) - lwz r10,THREAD+KSP_LIMIT(r2) - stw r4, THREAD+KSP_LIMIT(r2) stwu r1,THREAD_SIZE-STACK_FRAME_OVERHEAD(r4) mr r1,r4 - stw r10,8(r1) bl __do_irq - lwz r10,8(r1) lwz r1,0(r1) lwz r0,4(r1) - stw r10,THREAD+KSP_LIMIT(r2) mtlr r0 blr -- 2.13.3