On 27.03.2021 18:16:14, kernel test robot wrote:

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   0f4498cef9f5cd18d7c6639a2a902ec1edc5be4e
commit: eb79a267c9b3e608e7762a1b221428f37ace3aa3 can: mcp251xfd: rename all remaining occurrence to mcp251xfd
date:   6 months ago
config: mips-randconfig-r035-20210327 (attached as .config)
compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project d50fe9f0d6b9ee61df8830a67ea0a33c27a637e7)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install mips cross compiling tool for clang build
        # apt-get install binutils-mips-linux-gnu
        # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=eb79a267c9b3e608e7762a1b221428f37ace3aa3
        git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
        git fetch --no-tags linus master
        git checkout eb79a267c9b3e608e7762a1b221428f37ace3aa3
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=mips 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <redacted>

All warnings (new ones prefixed by >>):

[...]

quoted

quoted

drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c:2267:16: warning: taking address of packed member 'hw_tx_obj' of class or structure 'mcp251xfd_tx_obj_load_buf::(anonymous)' may result in an unaligned pointer value [-Waddress-of-packed-member]

                   hw_tx_obj = &load_buf->crc.hw_tx_obj;
                                ^~~~~~~~~~~~~~~~~~~~~~~
   drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c:2269:16: warning: taking address of packed member 'hw_tx_obj' of class or structure 'mcp251xfd_tx_obj_load_buf::(anonymous)' may result in an unaligned pointer value [-Waddress-of-packed-member]
                   hw_tx_obj = &load_buf->nocrc.hw_tx_obj;
                                ^~~~~~~~~~~~~~~~~~~~~~~~~
   4 warnings and 1 error generated.

That warning is technically correct, hw_tx_obj is an unaligned pointer in
the first warning, but...

vim +2267 drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c

55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine-Budde 2020-09-18  2215  static void
eb79a267c9b3e6 drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c Marc Kleine-Budde 2020-09-30  2216  mcp251xfd_tx_obj_from_skb(const struct mcp251xfd_priv *priv,
eb79a267c9b3e6 drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c Marc Kleine-Budde 2020-09-30  2217  			  struct mcp251xfd_tx_obj *tx_obj,
55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine-Budde 2020-09-18  2218  			  const struct sk_buff *skb,
55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine-Budde 2020-09-18  2219  			  unsigned int seq)
55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine-Budde 2020-09-18  2220  {

[...]

55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine-Budde 2020-09-18  2265  	load_buf = &tx_obj->buf;
eb79a267c9b3e6 drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c Marc Kleine-Budde 2020-09-30  2266  	if (priv->devtype_data.quirks & MCP251XFD_QUIRK_CRC_TX)
55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine-Budde 2020-09-18 @2267  		hw_tx_obj = &load_buf->crc.hw_tx_obj;
55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine-Budde 2020-09-18  2268  	else
55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine-Budde 2020-09-18  2269  		hw_tx_obj = &load_buf->nocrc.hw_tx_obj;
55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine-Budde 2020-09-18  2270  
55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine-Budde 2020-09-18  2271  	put_unaligned_le32(id, &hw_tx_obj->id);
55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine-Budde 2020-09-18  2272  	put_unaligned_le32(flags, &hw_tx_obj->flags);
55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine-Budde 2020-09-18  2273  
55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine-Budde 2020-09-18  2274  	/* Clear data at end of CAN frame */
55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine-Budde 2020-09-18  2275  	offset = round_down(cfd->len, sizeof(u32));
55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine-Budde 2020-09-18  2276  	len = round_up(can_dlc2len(dlc), sizeof(u32)) - offset;
eb79a267c9b3e6 drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c Marc Kleine-Budde 2020-09-30  2277  	if (MCP251XFD_SANITIZE_CAN && len)
55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine-Budde 2020-09-18  2278  		memset(hw_tx_obj->data + offset, 0x0, len);
55e5b97f003e85 drivers/net/can/spi/mcp25xxfd/mcp25xxfd-core.c Marc Kleine-Budde 2020-09-18  2279  	memcpy(hw_tx_obj->data, cfd->data, cfd->len);

...it's only accessed via put_unaligned_* and memset()/memcpy().

Marc

-- 
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