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Date:   Mon, 10 May 2021 07:36:10 +0100
From:   Christoph Hellwig <hch@infradead.org>
To:     Heiner Kallweit <hkallweit1@gmail.com>
Cc:     Bjorn Helgaas <bhelgaas@google.com>,
        "linux-pci@vger.kernel.org" <linux-pci@vger.kernel.org>,
        Bjorn Helgaas <helgaas@kernel.org>
Subject: Re: [PATCH v2] PCI/VPD: Use unaligned access helpers in pci_vpd_read
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On Sat, May 08, 2021 at 12:29:15AM +0200, Heiner Kallweit wrote:
> +
> +		if (len == 4)  {
> +			put_unaligned_le32(val, buf);
> +		} else {
> +			cpu_to_le32s(&val);
> +			memcpy(buf, (u8 *)&val + skip, len);

cpu_to_le32s is a horrible API that breaks endianess annotations.

Is the intent of this code to only put 16 bits in?  Why not something
like:

		switch (len) {
		case 4:
			put_unaligned_le32(val, buf);
			break;
		case 2:
			put_unaligned_le16(val, buf + 2);
			break;
		case 1:
			buf[3] = val;
			break;
  		}