On 10/11/2017 03:43 PM, Maninder Singh wrote: > Issue observed on ARM. > > Whenever there is switch from user mode, we end up with invalid last entry > with some user space address as below:- > > save_stack+0x40/0xec > __set_page_owner+0x2c/0x64 > .... > .... > __handle_domain_irq+0x9c/0x130 > gic_handle_irq+0x40/0x80 > __irq_usr+0x4c/0x60 > 0xb6507818 >
Sounds like an ARM issue to me. ... > diff --git a/lib/stackdepot.c b/lib/stackdepot.c > index f87d138..a045748 100644 > --- a/lib/stackdepot.c > +++ b/lib/stackdepot.c > @@ -214,6 +214,13 @@ depot_stack_handle_t depot_save_stack(struct stack_trace > *trace, > if (unlikely(trace->nr_entries == 0)) > goto fast_exit; > > + /* > + * Ignore last entry if it belongs to user space And if it belongs to module too. NACK. > + * in case of switch from user mode. > + */ > + if (!kernel_text_address(trace->entries[trace->nr_entries - 1])) > + trace->nr_entries--; > + > hash = hash_stack(trace->entries, trace->nr_entries); > bucket = &stack_table[hash & STACK_HASH_MASK]; > >
