Re: [Regression] Commit "tpm: Introduce function to poll for result of self test" breaks suspend

[Stefan Berger <stefanb@linux.vnet.ibm.com>]

On 01/16/2012 05:50 PM, Rafael J. Wysocki wrote:
> On Monday, January 16, 2012, Stefan Berger wrote:
>> On 01/16/2012 05:05 PM, Rafael J. Wysocki wrote:
> Yes, there are.  Below is the result of grepping tpm in dmesg output (the
> entire dmesg log from that box is attached).
>
> [    5.066807] tpm_tis 00:0a: 1.2 TPM (device-id 0xB, rev-id 16)
> [    7.167236] tpm_tis 00:0a: Adjusting TPM timeout parameters.
> [    7.893190] tpm_tis 00:0a: A TPM error (7) occurred attempting to read a pcr value
> [    7.897202] tpm_tis 00:0a: TPM self test failed
> [    7.907599] tpm_inf_pnp 00:0a: Found TPM with ID IFX0102
> [    7.909745] tpm_inf_pnp 00:0a: TPM found: config base 0x4e, data base 0x680, chip version 0x000b, vendor id 0x15d1 (Infineon), product id 0x000b (SLB 9635 TT 1.2)
> [   96.386200] tpm_inf_pnp 00:0a: saving TPM state
> [   96.407630] tpm_inf_pnp 00:0a: Timeout while clearing FIFO
> [   96.407634] tpm_inf_pnp 00:0a: error while saving TPM state
>
> Thanks,
> Rafael
If possible, I'd like the patch to stick a little longer. Can you try 
the following and tell me whether this solves the problem with the 
suspend/resume.

This patch handles the error codes reading of a PCR may cause when a TPM 
is disabled and/or deactivated. They would not be a reason for the 
tpm_do_selftest function to fail.

Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>

---
  drivers/char/tpm/tpm.c |    9 +++++++++
  drivers/char/tpm/tpm.h |    3 +++
  2 files changed, 12 insertions(+)

Index: linux-2.6/drivers/char/tpm/tpm.c
===================================================================
--- linux-2.6.orig/drivers/char/tpm/tpm.c
+++ linux-2.6/drivers/char/tpm/tpm.c
@@ -846,6 +846,15 @@ int tpm_do_selftest(struct tpm_chip *chi

      do {
          rc = __tpm_pcr_read(chip, 0, digest);
+        if (rc == TPM_ERR_DISABLED || rc == TPM_ERR_DEACTIVATED) {
+            dev_info(chip->dev,
+                 "TPM is disabled/deactivated (0x%X)\n", rc);
+            /* TPM is disabled and/or deactivated; driver can proceed
+             * and TPM does handle commands during suspend/resume
+             */
+            rc = 0;
+            break;
+        }
          if (rc != TPM_WARN_DOING_SELFTEST)
              return rc;
          msleep(delay_msec);
Index: linux-2.6/drivers/char/tpm/tpm.h
===================================================================
--- linux-2.6.orig/drivers/char/tpm/tpm.h
+++ linux-2.6/drivers/char/tpm/tpm.h
@@ -39,6 +39,9 @@ enum tpm_addr {
  };

  #define TPM_WARN_DOING_SELFTEST 0x802
+#define TPM_ERR_DEACTIVATED     0x6
+#define TPM_ERR_DISABLED        0x7
+
  #define TPM_HEADER_SIZE        10
  extern ssize_t tpm_show_pubek(struct device *, struct device_attribute 
*attr,
                  char *);