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Subject: Re: Is this a kernel BUG? ///Re: [Question] Can we use SIGRTMIN when
 vdso disabled on X86?
To:     "Leizhen (ThunderTown)" <thunder.leizhen@huawei.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, x86l <x86@kernel.org>,
        Dominik Brodowski <linux@dominikbrodowski.net>,
        Andy Lutomirski <luto@kernel.org>,
        linux-kernel <linux-kernel@vger.kernel.org>
Cc:     yaomin2@huawei.com
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 <5B188E2B.7040700@huawei.com>
From:   "H. Peter Anvin" <hpa@zytor.com>
Message-ID: <64b61360-803d-b987-6721-e9eb0ebe63a7@zytor.com>
Date:   Thu, 7 Jun 2018 14:05:45 -0700
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On 06/06/18 18:45, Leizhen (ThunderTown) wrote:
>>
>> The use of signals without SA_RESTORER is considered obsolete, but it's somewhat surprising that the vdso isn't there; it should be mapped even for static binaries esp. on i386 since it is the preferred way to do system calls (you don't need to parse the ELF for that.) Are you explicitly disabling the VDSO? If so, Don't Do That.
> 
> Yes, the vdso was explicitly disabled by the tester. Thanks.
> 

Are there any use cases that calls for this?  Maybe we should drop this
option.

	-hpa