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Date: Thu, 16 Nov 2017 16:27:07 +0000 (UTC)
From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
To: Peter Zijlstra <peterz@infradead.org>
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Subject: Re: [RFC PATCH v11 for 4.15 01/24] Restartable sequences system
 call
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----- On Nov 16, 2017, at 11:18 AM, Peter Zijlstra peterz@infradead.org wrote:

> 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.

I should as well make all those a bitmask within a "u32 rseq_event_mask" then,
sounds fair ?

Thanks,

Mathieu

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

-- 
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com