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Subject: Re: [PATCH v12 20/22] selftests/vm: testcases must restore
 pkey-permissions
To:     Ram Pai <linuxram@us.ibm.com>, shuahkh@osg.samsung.com,
        linux-kselftest@vger.kernel.org
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From:   Dave Hansen <dave.hansen@intel.com>
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Date:   Fri, 16 Mar 2018 15:32:38 -0700
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On 02/21/2018 05:55 PM, Ram Pai wrote:
> Generally the signal handler restores the state of the pkey register
> before returning. However there are times when the read/write operation
> can legitamely fail without invoking the signal handler.  Eg: A
> sys_read() operaton to a write-protected page should be disallowed.  In
> such a case the state of the pkey register is not restored to its
> original state.  The test case is responsible for restoring the key
> register state to its original value.

Oh, that's a good point.

Could we just do this in a common place, though?  Like reset the
register after each test?  Seems more foolproof.