tpm: fix crash in tpm_tis deinitialization

rmmod crashes the driver because tpm_chip_unregister() already sets ops
to NULL. This commit fixes the issue by moving tpm2_shutdown() to
tpm_chip_unregister(). This commit is also cleanup because it removes
duplicate code from tpm_crb and tpm_tis to the core.

Fixes: 4d3eac5e156a ("tpm: Provide strong locking for device removal")
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>

4 files changed, 1 insertions, 7 deletions

diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
index f62c8518cd68..5bc530ccbb86 100644
--- a/drivers/char/tpm/tpm-chip.c
+++ b/drivers/char/tpm/tpm-chip.c
@@ -269,6 +269,7 @@ static void tpm_del_char_device(struct tpm_chip *chip)
 
         /* Make the driver uncallable. */
         down_write(&chip->ops_sem);
+        tpm2_shutdown(chip, TPM2_SU_CLEAR);
         chip->ops = NULL;
         up_write(&chip->ops_sem);
 }
diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index 5fc0e7c64daa..e42266589ce6 100644
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -773,7 +773,6 @@ void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type)
                 dev_warn(&chip->dev, "transmit returned %d while stopping the TPM",
                          rc);
 }
-EXPORT_SYMBOL_GPL(tpm2_shutdown);
 
 /*
  * tpm2_calc_ordinal_duration() - maximum duration for a command
diff --git a/drivers/char/tpm/tpm_crb.c b/drivers/char/tpm/tpm_crb.c
index a12b31940344..ec734de87b76 100644
--- a/drivers/char/tpm/tpm_crb.c
+++ b/drivers/char/tpm/tpm_crb.c
@@ -344,9 +344,6 @@ static int crb_acpi_remove(struct acpi_device *device)
         struct device *dev = &device->dev;
         struct tpm_chip *chip = dev_get_drvdata(dev);
 
-        if (chip->flags & TPM_CHIP_FLAG_TPM2)
-                tpm2_shutdown(chip, TPM2_SU_CLEAR);
-
         tpm_chip_unregister(chip);
 
         return 0;
diff --git a/drivers/char/tpm/tpm_tis.c b/drivers/char/tpm/tpm_tis.c
index 18236f66c084..0b0d44f9aaf2 100644
--- a/drivers/char/tpm/tpm_tis.c
+++ b/drivers/char/tpm/tpm_tis.c
@@ -653,9 +653,6 @@ static void tpm_tis_remove(struct tpm_chip *chip)
         void __iomem *reg = chip->vendor.iobase +
                 TPM_INT_ENABLE(chip->vendor.locality);
 
-        if (chip->flags & TPM_CHIP_FLAG_TPM2)
-                tpm2_shutdown(chip, TPM2_SU_CLEAR);
-
         iowrite32(~TPM_GLOBAL_INT_ENABLE & ioread32(reg), reg);
         release_locality(chip, chip->vendor.locality, 1);
 }