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author | Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> | 2015-03-01 22:55:47 +0100 |
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committer | Peter Huewe <peterhuewe@gmx.de> | 2015-03-06 22:35:49 +0100 |
commit | 19913b6db3aa417d855318c9cf5b40fbc1f28e52 (patch) | |
tree | edc596fc2c6577237680788ace8d2736c9270d3d /drivers/char | |
parent | tpm/ibmvtpm: Additional LE support for tpm_ibmvtpm_send (diff) | |
download | linux-19913b6db3aa417d855318c9cf5b40fbc1f28e52.tar.xz linux-19913b6db3aa417d855318c9cf5b40fbc1f28e52.zip |
tpm: fix call order in tpm-chip.c
- tpm_dev_add_device(): cdev_add() must be done before uevent is
propagated in order to avoid races.
- tpm_chip_register(): tpm_dev_add_device() must be done as the
last step before exposing device to the user space in order to
avoid races.
In addition clarified description in tpm_chip_register().
Fixes: 313d21eeab92 ("tpm: device class for tpm")
Fixes: afb5abc262e9 ("tpm: two-phase chip management functions")
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Diffstat (limited to 'drivers/char')
-rw-r--r-- | drivers/char/tpm/tpm-chip.c | 34 |
1 files changed, 14 insertions, 20 deletions
diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c index 1d278ccd751f..e096e9cddb40 100644 --- a/drivers/char/tpm/tpm-chip.c +++ b/drivers/char/tpm/tpm-chip.c @@ -140,24 +140,24 @@ static int tpm_dev_add_device(struct tpm_chip *chip) { int rc; - rc = device_add(&chip->dev); + rc = cdev_add(&chip->cdev, chip->dev.devt, 1); if (rc) { dev_err(&chip->dev, - "unable to device_register() %s, major %d, minor %d, err=%d\n", + "unable to cdev_add() %s, major %d, minor %d, err=%d\n", chip->devname, MAJOR(chip->dev.devt), MINOR(chip->dev.devt), rc); + device_unregister(&chip->dev); return rc; } - rc = cdev_add(&chip->cdev, chip->dev.devt, 1); + rc = device_add(&chip->dev); if (rc) { dev_err(&chip->dev, - "unable to cdev_add() %s, major %d, minor %d, err=%d\n", + "unable to device_register() %s, major %d, minor %d, err=%d\n", chip->devname, MAJOR(chip->dev.devt), MINOR(chip->dev.devt), rc); - device_unregister(&chip->dev); return rc; } @@ -174,27 +174,17 @@ static void tpm_dev_del_device(struct tpm_chip *chip) * tpm_chip_register() - create a character device for the TPM chip * @chip: TPM chip to use. * - * Creates a character device for the TPM chip and adds sysfs interfaces for - * the device, PPI and TCPA. As the last step this function adds the - * chip to the list of TPM chips available for use. + * Creates a character device for the TPM chip and adds sysfs attributes for + * the device. As the last step this function adds the chip to the list of TPM + * chips available for in-kernel use. * - * NOTE: This function should be only called after the chip initialization - * is complete. - * - * Called from tpm_<specific>.c probe function only for devices - * the driver has determined it should claim. Prior to calling - * this function the specific probe function has called pci_enable_device - * upon errant exit from this function specific probe function should call - * pci_disable_device + * This function should be only called after the chip initialization is + * complete. */ int tpm_chip_register(struct tpm_chip *chip) { int rc; - rc = tpm_dev_add_device(chip); - if (rc) - return rc; - /* Populate sysfs for TPM1 devices. */ if (!(chip->flags & TPM_CHIP_FLAG_TPM2)) { rc = tpm_sysfs_add_device(chip); @@ -208,6 +198,10 @@ int tpm_chip_register(struct tpm_chip *chip) chip->bios_dir = tpm_bios_log_setup(chip->devname); } + rc = tpm_dev_add_device(chip); + if (rc) + return rc; + /* Make the chip available. */ spin_lock(&driver_lock); list_add_rcu(&chip->list, &tpm_chip_list); |