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authorJarkko Sakkinen <jarkko.sakkinen@linux.intel.com>2015-11-07 13:33:25 +0200
committerJarkko Sakkinen <jarkko.sakkinen@linux.intel.com>2015-11-09 17:52:56 +0200
commitd56e4f75346933dd2cb11533a668ce883908c859 (patch)
tree943b7852ed98c6cf34ecf2fcd025f1476d86338a /drivers/char
parent2e31125c241212e2407d61a2d1cbdad0055a30b0 (diff)
tpm: fix compat 'ppi' link handling in tpm_chip_register()
__compat_only_sysfs_link_entry_to_kobj() was unconditionally called for TPM1 chips, which caused crash on Acer C720 laptop where DSM for the ACPI object did not exist. There are two reasons for unwanted behavior: * The code did not check whether __compat_only_sysfs_link_entry_to_kobj() returned -ENOENT. This is OK. It just meanst that ppi is not available. * The code did not clean up properly. Compat link should added only after all other init is done. This patch sorts out these issues. Fixes: 9b774d5cf2db Reported-by: Jeremiah Mahler <jmmahler@gmail.com> Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Tested-by: Jeremiah Mahler <jmmahler@gmail.com> Acked-by: Peter Huewe <PeterHuewe@gmx.de>
Diffstat (limited to 'drivers/char')
-rw-r--r--drivers/char/tpm/tpm-chip.c18
1 files changed, 10 insertions, 8 deletions
diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
index a5cdce74adab..45cc39aabeee 100644
--- a/drivers/char/tpm/tpm-chip.c
+++ b/drivers/char/tpm/tpm-chip.c
@@ -226,14 +226,6 @@ int tpm_chip_register(struct tpm_chip *chip)
if (rc)
goto out_err;
- if (!(chip->flags & TPM_CHIP_FLAG_TPM2)) {
- rc = __compat_only_sysfs_link_entry_to_kobj(&chip->pdev->kobj,
- &chip->dev.kobj,
- "ppi");
- if (rc)
- goto out_err;
- }
-
/* Make the chip available. */
spin_lock(&driver_lock);
list_add_tail_rcu(&chip->list, &tpm_chip_list);
@@ -241,6 +233,16 @@ int tpm_chip_register(struct tpm_chip *chip)
chip->flags |= TPM_CHIP_FLAG_REGISTERED;
+ if (!(chip->flags & TPM_CHIP_FLAG_TPM2)) {
+ rc = __compat_only_sysfs_link_entry_to_kobj(&chip->pdev->kobj,
+ &chip->dev.kobj,
+ "ppi");
+ if (rc && rc != -ENOENT) {
+ tpm_chip_unregister(chip);
+ return rc;
+ }
+ }
+
return 0;
out_err:
tpm1_chip_unregister(chip);