Re: [RFC PATCH v11 for 4.15 01/24] Restartable sequences system call

From: Peter Zijlstra
Date: Thu Nov 16 2017 - 11:19:18 EST


On Tue, Nov 14, 2017 at 03:03:51PM -0500, Mathieu Desnoyers wrote:
> @@ -977,6 +978,13 @@ struct task_struct {
> unsigned long numa_pages_migrated;
> #endif /* CONFIG_NUMA_BALANCING */
>
> +#ifdef CONFIG_RSEQ
> + struct rseq __user *rseq;
> + u32 rseq_len;
> + u32 rseq_sig;
> + bool rseq_preempt, rseq_signal, rseq_migrate;

No bool please. Use something that has a defined size in ILP32/LP64.
_Bool makes it absolutely impossible to speculate on structure layout
across architectures.

> +#endif
> +
> struct tlbflush_unmap_batch tlb_ubc;
>
> struct rcu_head rcu;