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Date:   Mon, 9 Mar 2020 14:14:25 -0700
From:   Sean Christopherson <sean.j.christopherson@intel.com>
To:     Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc:     linux-kernel@vger.kernel.org, x86@kernel.org,
        linux-sgx@vger.kernel.org, akpm@linux-foundation.org,
        dave.hansen@intel.com, nhorman@redhat.com, npmccallum@redhat.com,
        haitao.huang@intel.com, andriy.shevchenko@linux.intel.com,
        tglx@linutronix.de, kai.svahn@intel.com, bp@alien8.de,
        josh@joshtriplett.org, luto@kernel.org, kai.huang@intel.com,
        rientjes@google.com, cedric.xing@intel.com, puiterwijk@redhat.com
Subject: Re: [PATCH v28 06/22] x86/sgx: Add wrappers for ENCLS leaf functions
Message-ID: <20200309211425.GA19235@linux.intel.com>
References: <20200303233609.713348-1-jarkko.sakkinen@linux.intel.com>
 <20200303233609.713348-7-jarkko.sakkinen@linux.intel.com>
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On Wed, Mar 04, 2020 at 01:35:53AM +0200, Jarkko Sakkinen wrote:
> +/* Issue a WARN() about an ENCLS leaf. */
> +#define ENCLS_WARN(r, name) {						  \
> +	do {								  \
> +		int _r = (r);						  \
> +		WARN(_r, "%s returned %d (0x%x)\n", (name), _r, _r); \

This should be a WARN_ONCE(), otherwise we'll spam the log if something
goes awry, e.g. if there's a correctable #MC or a rogue write to a MCi_CTL
MSR, either of which will "soft" disable SGX (CPUID 0x7 still reports
SGX/SGXLC support, but all CPUID 0x12 sub-leafs return zeros).

> +	} while (0);							  \
> +}