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To:     Thomas Gleixner <tglx@linutronix.de>
Cc:     Jiri Kosina <jikos@kernel.org>,
        Tom Lendacky <thomas.lendacky@amd.com>,
        Ingo Molnar <mingo@redhat.com>,
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        Andi Kleen <ak@linux.intel.com>,
        Dave Hansen <dave.hansen@intel.com>,
        Casey Schaufler <casey.schaufler@intel.com>,
        Asit Mallick <asit.k.mallick@intel.com>,
        Arjan van de Ven <arjan@linux.intel.com>,
        Jon Masters <jcm@redhat.com>, linux-kernel@vger.kernel.org,
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References: <cover.1537920575.git.tim.c.chen@linux.intel.com>
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From:   Tim Chen <tim.c.chen@linux.intel.com>
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Subject: Re: [Patch v2 4/4] x86/speculation: Add prctl to control indirect
 branch speculation per process
Message-ID: <5a558b4e-e241-2ab8-3653-b25dc014b78d@linux.intel.com>
Date:   Fri, 5 Oct 2018 11:12:23 -0700
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Sender: linux-kernel-owner@vger.kernel.org
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On 10/02/2018 10:58 AM, Thomas Gleixner wrote:
> On Tue, 25 Sep 2018, Tim Chen wrote:
>>  
>> +void arch_set_dumpable(struct task_struct *tsk, struct mm_struct *mm, int value)
>> +{
>> +	if (!static_branch_unlikely(&spectre_v2_app_lite))
>> +		return;
>> +	if (!static_cpu_has(X86_FEATURE_STIBP))
>> +		return;
>> +
>> +	if ((unsigned) value != SUID_DUMP_USER) {
> 
> First of all we use unsigned int and not unsigned, Aside of that why is the
> argument not unsigned int right away?


The original set_dumpable passes suid_dumpable, which was
exposed via /proc/sys/fs/suid_dumpable and defined as int.
It will make sense to define suid_dumpable as an unsigned int instead.

Would you like me to redefine suid_dumpable as unsigned int
in sysctl.c in the patch revision as a separate clean up patch?

Thanks.

Tim