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Date: Mon, 14 Aug 2023 13:21:44 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Dan Williams <dan.j.williams@intel.com>
Cc: linux-coco@lists.linux.dev, Borislav Petkov <bp@alien8.de>,
	Tom Lendacky <thomas.lendacky@amd.com>,
	Dionna Glaze <dionnaglaze@google.com>,
	Brijesh Singh <brijesh.singh@amd.com>, x86@kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 5/5] virt: sevguest: Add TSM_REPORTS support for
 SNP_{GET, GET_EXT}_REPORT
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References: <169199898909.1782217.10899362240465838600.stgit@dwillia2-xfh.jf.intel.com>
 <169199901829.1782217.16990408177897780160.stgit@dwillia2-xfh.jf.intel.com>
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In-Reply-To: <169199901829.1782217.16990408177897780160.stgit@dwillia2-xfh.jf.intel.com>

On Mon, Aug 14, 2023 at 12:43:38AM -0700, Dan Williams wrote:
> +static u8 *sev_report_new(struct device *dev, const struct tsm_desc *desc,

> +			  size_t *outblob_len)
> +{

> +
> +	u8 *buf __free(kvfree) = kvzalloc(size, GFP_KERNEL);
> +

> +
> +	*outblob_len = size;
> +	no_free_ptr(buf);
> +	return buf;

This seems broken, no_free_ptr(x) is basically xchg(X, NULL) (except no
atomics). So the above would end up being:

	return NULL;

What you want to write is somehting like:

	return no_free_ptr(buf);

or, a convenient shorthand:

	return_ptr(buf);