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Date:   Sat, 21 Jan 2023 20:34:09 -0800
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Subject: Re: the x86 sysret_rip test fails on the Intel FRED architecture
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To:     "Li, Xin3" <xin3.li@intel.com>, "H. Peter Anvin" <hpa@zytor.com>,
        "tglx@linutronix.de" <tglx@linutronix.de>,
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        "dave.hansen@linux.intel.com" <dave.hansen@linux.intel.com>
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        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
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From:   Dave Hansen <dave.hansen@intel.com>
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On 1/21/23 19:38, Li, Xin3 wrote:
>> However, it doesn't seem to make sense to do so to me. The current behavior is
>> much more of an artifact than desired behavior.
> We kind of have an agreement that %r11 = %flags after returning from the kernel.
> 
> And the question is, is it what we want?

Can the selftest just set r11=rflags before the syscall?  The old
syscall entry path will set r11=rflags.  The FRED path won't touch it.
Either case will pass an r11==rflags check.