[jarkko-tpmdd:queue 12/15] drivers/char/tpm/tpm2-sessions.c:261:27: warning: unused variable 'auth'

[jarkko-tpmdd:queue 12/15] drivers/char/tpm/tpm2-sessions.c:261:27: warning: unused variable 'auth'

[kernel test robot]

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd.git queue
head:   fbd9af022416579062d59e206c7f71890d27fc31
commit: 67a0e52127ec9057ddcb47bca6cd267f2a3d20a7 [12/15] tpm2-sessions: Remove the support for more than one authorization
config: sparc-randconfig-002-20260126 (https://download.01.org/0day-ci/archive/20260126/202601260825.EMdrikNe-lkp@intel.com/config)
compiler: sparc-linux-gcc (GCC) 11.5.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260126/202601260825.EMdrikNe-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202601260825.EMdrikNe-lkp@intel.com/

All warnings (new ones prefixed by >>):

   drivers/char/tpm/tpm2-sessions.c: In function 'tpm_buf_append_name':
>> drivers/char/tpm/tpm2-sessions.c:261:27: warning: unused variable 'auth' [-Wunused-variable]
     261 |         struct tpm2_auth *auth;
         |                           ^~~~


vim +/auth +261 drivers/char/tpm/tpm2-sessions.c

a61809a3323982 Jarkko Sakkinen 2024-07-03  231  
a61809a3323982 Jarkko Sakkinen 2024-07-03  232  /**
7895041508233a Jarkko Sakkinen 2025-12-03  233   * tpm_buf_append_name() - Append a handle and store TPM name
7895041508233a Jarkko Sakkinen 2025-12-03  234   * @chip:		TPM chip to use.
7895041508233a Jarkko Sakkinen 2025-12-03  235   * @buf:		TPM buffer containing the TPM command in-transit.
7895041508233a Jarkko Sakkinen 2025-12-03  236   * @handle:		TPM handle to be appended.
7895041508233a Jarkko Sakkinen 2025-12-03  237   * @name:		TPM name of the handle
7895041508233a Jarkko Sakkinen 2025-12-03  238   * @name_size:		Size of the TPM name.
a61809a3323982 Jarkko Sakkinen 2024-07-03  239   *
a61809a3323982 Jarkko Sakkinen 2024-07-03  240   * In order to compute session HMACs, we need to know the names of the
a61809a3323982 Jarkko Sakkinen 2024-07-03  241   * objects pointed to by the handles.  For most objects, this is simply
a61809a3323982 Jarkko Sakkinen 2024-07-03  242   * the actual 4 byte handle or an empty buf (in these cases @name
a61809a3323982 Jarkko Sakkinen 2024-07-03  243   * should be NULL) but for volatile objects, permanent objects and NV
a61809a3323982 Jarkko Sakkinen 2024-07-03  244   * areas, the name is defined as the hash (according to the name
a61809a3323982 Jarkko Sakkinen 2024-07-03  245   * algorithm which should be set to sha256) of the public area to
a61809a3323982 Jarkko Sakkinen 2024-07-03  246   * which the two byte algorithm id has been appended.  For these
a61809a3323982 Jarkko Sakkinen 2024-07-03  247   * objects, the @name pointer should point to this.  If a name is
a61809a3323982 Jarkko Sakkinen 2024-07-03  248   * required but @name is NULL, then TPM2_ReadPublic() will be called
a61809a3323982 Jarkko Sakkinen 2024-07-03  249   * on the handle to obtain the name.
a61809a3323982 Jarkko Sakkinen 2024-07-03  250   *
a61809a3323982 Jarkko Sakkinen 2024-07-03  251   * As with most tpm_buf operations, success is assumed because failure
a61809a3323982 Jarkko Sakkinen 2024-07-03  252   * will be caused by an incorrect programming model and indicated by a
a61809a3323982 Jarkko Sakkinen 2024-07-03  253   * kernel message.
6e9722e9a7bfe1 Jarkko Sakkinen 2025-11-30  254   *
7895041508233a Jarkko Sakkinen 2025-12-03  255   * Returns zero on success.
7895041508233a Jarkko Sakkinen 2025-12-03  256   * Returns -EIO when the authorization area state is malformed.
a61809a3323982 Jarkko Sakkinen 2024-07-03  257   */
6e9722e9a7bfe1 Jarkko Sakkinen 2025-11-30  258  int tpm_buf_append_name(struct tpm_chip *chip, struct tpm_buf *buf,
7895041508233a Jarkko Sakkinen 2025-12-03  259  			u32 handle, u8 *name, u16 name_size)
a61809a3323982 Jarkko Sakkinen 2024-07-03  260  {
a61809a3323982 Jarkko Sakkinen 2024-07-03 @261  	struct tpm2_auth *auth;
6e9722e9a7bfe1 Jarkko Sakkinen 2025-11-30  262  	int ret;
67a0e52127ec90 Jarkko Sakkinen 2025-12-08  263  
67a0e52127ec90 Jarkko Sakkinen 2025-12-08  264  	if (tpm_buf_length(buf) != TPM_HEADER_SIZE) {
67a0e52127ec90 Jarkko Sakkinen 2025-12-08  265  		dev_err(&chip->dev, "too many handles\n");
67a0e52127ec90 Jarkko Sakkinen 2025-12-08  266  		ret = -EIO;
67a0e52127ec90 Jarkko Sakkinen 2025-12-08  267  		goto err;
67a0e52127ec90 Jarkko Sakkinen 2025-12-08  268  	}
a61809a3323982 Jarkko Sakkinen 2024-07-03  269  
a61809a3323982 Jarkko Sakkinen 2024-07-03  270  	if (!tpm2_chip_auth(chip)) {
27184f8905ba68 Jarkko Sakkinen 2024-11-13  271  		tpm_buf_append_handle(chip, buf, handle);
6e9722e9a7bfe1 Jarkko Sakkinen 2025-11-30  272  		return 0;
a61809a3323982 Jarkko Sakkinen 2024-07-03  273  	}
a61809a3323982 Jarkko Sakkinen 2024-07-03  274  

:::::: The code at line 261 was first introduced by commit
:::::: a61809a33239821d70eba77bd0d6d13c29bbad0d tpm: Address !chip->auth in tpm_buf_append_name()

:::::: TO: Jarkko Sakkinen <jarkko@kernel.org>
:::::: CC: Jarkko Sakkinen <jarkko.sakkinen@iki.fi>

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