[PATCH] powerpc: Copy back TIF flags on return from softirq stack
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: 2011-07-19 03:17:37
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Michael Ellerman, Linus Torvalds
We already did it for hard IRQs but it looks like we forgot to do it for softirqs. Without this, we would lose flags such as TIF_NEED_RESCHED set using current_thread_info() by something running of a softirq. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- arch/powerpc/kernel/irq.c | 7 +++++++ 1 files changed, 7 insertions(+), 0 deletions(-)
diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c
index 164fb6c..4e7f1aa 100644
--- a/arch/powerpc/kernel/irq.c
+++ b/arch/powerpc/kernel/irq.c@@ -451,11 +451,18 @@ static inline void do_softirq_onstack(void) curtp = current_thread_info(); irqtp = softirq_ctx[smp_processor_id()]; irqtp->task = curtp->task; + irqtp->flags = 0; current->thread.ksp_limit = (unsigned long)irqtp + _ALIGN_UP(sizeof(struct thread_info), 16); call_do_softirq(irqtp); current->thread.ksp_limit = saved_sp_limit; irqtp->task = NULL; + + /* Set any flag that may have been set on the + * alternate stack + */ + if (irqtp->flags) + set_bits(irqtp->flags, &curtp->flags); } void do_softirq(void)