[PATCH v4 0/4] tpm: add update_durations class op to allow override of chip supplied values

[PATCH v4 0/4] tpm: add update_durations class op to allow override of chip supplied values

[Jerry Snitselaar]

We've run into a case where a customer has an STM TPM 1.2 chip
(version 1.2.8.28), that is getting into an inconsistent state and
they end up getting tpm transmit errors.  In really old tpm code this
wasn't seen because the code that grabbed the duration values from the
chip could fail silently, and would proceed to just use default values
and move forward. More recent code though successfully gets the
duration values from the chip, and using those values this particular
chip version gets into the state seen by the customer.

The idea with this patchset is to provide a facility like the
update_timeouts operation to allow the override of chip supplied
values.

changes from v3:
    * Assign value to version when tpm1_getcap is successful for TPM 1.1 device
      not when it fails.

changes from v2:
    * Added patch 1/3
    * Rework tpm_tis_update_durations to make use of new version structs
      and pull tpm1_getcap calls out of loop.

changes from v1:
    * Remove unneeded newline
    * Formatting cleanups
    * Change tpm_tis_update_durations to be a void function, and
      use chip->duration_adjusted to track whether adjustment was
      made.

Jarkko Sakkinen (1):
      tpm: Remove duplicate code from caps_show() in tpm-sysfs.c

Jerry Snitselaar (2):
      tpm: provide a way to override the chip returned durations
      tpm_tis: override durations for STM tpm with firmware 1.2.8.28

[PATCH v4 1/3] tpm: Remove duplicate code from caps_show() in tpm-sysfs.c

[Jerry Snitselaar]

From: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>

Replace existing TPM 1.x version structs with new structs that consolidate
the common parts into a single struct so that code duplication is no longer
needed in caps_show().

Cc: Peter Huewe <peterhuewe@gmx.de>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Alexey Klimov <aklimov@redhat.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Tested-by: Jerry Snitselaar <jsnitsel@redhat.com>
---
 drivers/char/tpm/tpm-sysfs.c | 45 ++++++++++++++++++------------------
 drivers/char/tpm/tpm.h       | 23 ++++++++----------
 2 files changed, 33 insertions(+), 35 deletions(-)

diff --git a/drivers/char/tpm/tpm-sysfs.c b/drivers/char/tpm/tpm-sysfs.c
index d9caedda075b..eb05d5df4759 100644
--- a/drivers/char/tpm/tpm-sysfs.c
+++ b/drivers/char/tpm/tpm-sysfs.c
@@ -217,6 +217,7 @@ static ssize_t caps_show(struct device *dev, struct device_attribute *attr,
 			 char *buf)
 {
 	struct tpm_chip *chip = to_tpm_chip(dev);
+	struct tpm1_version *version;
 	ssize_t rc = 0;
 	char *str = buf;
 	cap_t cap;
@@ -232,31 +233,31 @@ static ssize_t caps_show(struct device *dev, struct device_attribute *attr,
 	str += sprintf(str, "Manufacturer: 0x%x\n",
 		       be32_to_cpu(cap.manufacturer_id));
 
-	/* Try to get a TPM version 1.2 TPM_CAP_VERSION_INFO */
-	rc = tpm1_getcap(chip, TPM_CAP_VERSION_1_2, &cap,
+	/* TPM 1.2 */
+	if (!tpm1_getcap(chip, TPM_CAP_VERSION_1_2, &cap,
 			 "attempting to determine the 1.2 version",
-			 sizeof(cap.tpm_version_1_2));
-	if (!rc) {
-		str += sprintf(str,
-			       "TCG version: %d.%d\nFirmware version: %d.%d\n",
-			       cap.tpm_version_1_2.Major,
-			       cap.tpm_version_1_2.Minor,
-			       cap.tpm_version_1_2.revMajor,
-			       cap.tpm_version_1_2.revMinor);
-	} else {
-		/* Otherwise just use TPM_STRUCT_VER */
-		if (tpm1_getcap(chip, TPM_CAP_VERSION_1_1, &cap,
-				"attempting to determine the 1.1 version",
-				sizeof(cap.tpm_version)))
-			goto out_ops;
-		str += sprintf(str,
-			       "TCG version: %d.%d\nFirmware version: %d.%d\n",
-			       cap.tpm_version.Major,
-			       cap.tpm_version.Minor,
-			       cap.tpm_version.revMajor,
-			       cap.tpm_version.revMinor);
+			 sizeof(cap.version2))) {
+		version = &cap.version2.version;
+		goto out_print;
 	}
+
+	/* TPM 1.1 */
+	if (tpm1_getcap(chip, TPM_CAP_VERSION_1_1, &cap,
+			"attempting to determine the 1.1 version",
+			sizeof(cap.version1))) {
+		goto out_ops;
+	}
+
+	version = &cap.version1;
+
+out_print:
+	str += sprintf(str,
+		       "TCG version: %d.%d\nFirmware version: %d.%d\n",
+		       version->major, version->minor,
+		       version->rev_major, version->rev_minor);
+
 	rc = str - buf;
+
 out_ops:
 	tpm_put_ops(chip);
 	return rc;
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index a7fea3e0ca86..a4f74dd02a35 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -186,19 +186,16 @@ struct	stclear_flags_t {
 	u8	bGlobalLock;
 } __packed;
 
-struct	tpm_version_t {
-	u8	Major;
-	u8	Minor;
-	u8	revMajor;
-	u8	revMinor;
+struct tpm1_version {
+	u8 major;
+	u8 minor;
+	u8 rev_major;
+	u8 rev_minor;
 } __packed;
 
-struct	tpm_version_1_2_t {
-	__be16	tag;
-	u8	Major;
-	u8	Minor;
-	u8	revMajor;
-	u8	revMinor;
+struct tpm1_version2 {
+	__be16 tag;
+	struct tpm1_version version;
 } __packed;
 
 struct	timeout_t {
@@ -243,8 +240,8 @@ typedef union {
 	struct	stclear_flags_t	stclear_flags;
 	__u8	owned;
 	__be32	num_pcrs;
-	struct	tpm_version_t	tpm_version;
-	struct	tpm_version_1_2_t tpm_version_1_2;
+	struct tpm1_version version1;
+	struct tpm1_version2 version2;
 	__be32	manufacturer_id;
 	struct timeout_t  timeout;
 	struct duration_t duration;
-- 
2.21.0

[PATCH v4 2/3] tpm: provide a way to override the chip returned durations

[Jerry Snitselaar]

Patch adds method ->update_durations to override returned
durations in case TPM chip misbehaves for TPM 1.2 drivers.

Cc: Peter Huewe <peterhuewe@gmx.de>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Signed-off-by: Alexey Klimov <aklimov@redhat.com>
Signed-off-by: Jerry Snitselaar <jsnitsel@redhat.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
---
 drivers/char/tpm/tpm1-cmd.c | 15 +++++++++++++++
 include/linux/tpm.h         |  2 ++
 2 files changed, 17 insertions(+)

diff --git a/drivers/char/tpm/tpm1-cmd.c b/drivers/char/tpm/tpm1-cmd.c
index 149e953ca369..ca7158fa6e6c 100644
--- a/drivers/char/tpm/tpm1-cmd.c
+++ b/drivers/char/tpm/tpm1-cmd.c
@@ -343,6 +343,7 @@ int tpm1_get_timeouts(struct tpm_chip *chip)
 {
 	cap_t cap;
 	unsigned long timeout_old[4], timeout_chip[4], timeout_eff[4];
+	unsigned long durations[3];
 	ssize_t rc;
 
 	rc = tpm1_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, NULL,
@@ -427,6 +428,20 @@ int tpm1_get_timeouts(struct tpm_chip *chip)
 		usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_long));
 	chip->duration[TPM_LONG_LONG] = 0; /* not used under 1.2 */
 
+	/*
+	 * Provide the ability for vendor overrides of duration values in case
+	 * of misreporting.
+	 */
+	if (chip->ops->update_durations)
+		chip->ops->update_durations(chip, durations);
+
+	if (chip->duration_adjusted) {
+		dev_info(&chip->dev, HW_ERR "Adjusting reported durations.");
+		chip->duration[TPM_SHORT] = durations[0];
+		chip->duration[TPM_MEDIUM] = durations[1];
+		chip->duration[TPM_LONG] = durations[2];
+	}
+
 	/* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
 	 * value wrong and apparently reports msecs rather than usecs. So we
 	 * fix up the resulting too-small TPM_SHORT value to make things work.
diff --git a/include/linux/tpm.h b/include/linux/tpm.h
index 53c0ea9ec9df..bb1d1ac7081d 100644
--- a/include/linux/tpm.h
+++ b/include/linux/tpm.h
@@ -67,6 +67,8 @@ struct tpm_class_ops {
 	u8 (*status) (struct tpm_chip *chip);
 	void (*update_timeouts)(struct tpm_chip *chip,
 				unsigned long *timeout_cap);
+	void (*update_durations)(struct tpm_chip *chip,
+				 unsigned long *duration_cap);
 	int (*go_idle)(struct tpm_chip *chip);
 	int (*cmd_ready)(struct tpm_chip *chip);
 	int (*request_locality)(struct tpm_chip *chip, int loc);
-- 
2.21.0

[PATCH v4 3/3] tpm_tis: override durations for STM tpm with firmware 1.2.8.28

[Jerry Snitselaar]

There was revealed a bug in the STM TPM chipset used in Dell R415s.
Bug is observed so far only on chipset firmware 1.2.8.28
(1.2 TPM, device-id 0x0, rev-id 78). After some number of
operations chipset hangs and stays in inconsistent state:

tpm_tis 00:09: Operation Timed out
tpm_tis 00:09: tpm_transmit: tpm_send: error -5

Durations returned by the chip are the same like on other
firmware revisions but apparently with specifically 1.2.8.28 fw
durations should be reset to 2 minutes to enable tpm chip work
properly. No working way of updating firmware was found.

This patch adds implementation of ->update_durations method
that matches only STM devices with specific firmware version.

Cc: Peter Huewe <peterhuewe@gmx.de>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Signed-off-by: Alexey Klimov <aklimov@redhat.com>
Signed-off-by: Jerry Snitselaar <jsnitsel@redhat.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
---
 drivers/char/tpm/tpm_tis_core.c | 79 +++++++++++++++++++++++++++++++++
 1 file changed, 79 insertions(+)

diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index c3181ea9f271..27c6ca031e23 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -506,6 +506,84 @@ static int tpm_tis_send(struct tpm_chip *chip, u8 *buf, size_t len)
 	return rc;
 }
 
+struct tis_vendor_durations_override {
+	u32 did_vid;
+	struct tpm1_version version;
+	unsigned long durations[3];
+};
+
+static const struct  tis_vendor_durations_override vendor_dur_overrides[] = {
+	/* STMicroelectronics 0x104a */
+	{ 0x0000104a,
+	  { 1, 2, 8, 28 },
+	  { (2 * 60 * HZ), (2 * 60 * HZ), (2 * 60 * HZ) } },
+};
+
+static void tpm_tis_update_durations(struct tpm_chip *chip,
+				     unsigned long *duration_cap)
+{
+	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
+	struct tpm1_version *version;
+	u32 did_vid;
+	int i, rc;
+	cap_t cap;
+
+	chip->duration_adjusted = false;
+
+	if (chip->ops->clk_enable != NULL)
+		chip->ops->clk_enable(chip, true);
+
+	rc = tpm_tis_read32(priv, TPM_DID_VID(0), &did_vid);
+	if (rc < 0) {
+		dev_warn(&chip->dev, "%s: failed to read did_vid. %d\n",
+			 __func__, rc);
+		goto out;
+	}
+
+	/* Try to get a TPM version 1.2 or 1.1 TPM_CAP_VERSION_INFO */
+	rc = tpm1_getcap(chip, TPM_CAP_VERSION_1_2, &cap,
+			 "attempting to determine the 1.2 version",
+			 sizeof(cap.version2));
+	if (!rc) {
+		version = &cap.version2.version;
+	} else {
+		rc = tpm1_getcap(chip, TPM_CAP_VERSION_1_1, &cap,
+				 "attempting to determine the 1.1 version",
+				 sizeof(cap.version1));
+
+		if (rc)
+			goto out;
+
+		version = &cap.version1;
+	}
+
+	for (i = 0; i != ARRAY_SIZE(vendor_dur_overrides); i++) {
+		if (vendor_dur_overrides[i].did_vid != did_vid)
+			continue;
+
+		if ((version->major ==
+		     vendor_dur_overrides[i].version.major) &&
+		    (version->minor ==
+		     vendor_dur_overrides[i].version.minor) &&
+		    (version->rev_major ==
+		     vendor_dur_overrides[i].version.rev_major) &&
+		    (version->rev_minor ==
+		     vendor_dur_overrides[i].version.rev_minor)) {
+
+			memcpy(duration_cap,
+			       vendor_dur_overrides[i].durations,
+			       sizeof(vendor_dur_overrides[i].durations));
+
+			chip->duration_adjusted = true;
+			goto out;
+		}
+	}
+
+out:
+	if (chip->ops->clk_enable != NULL)
+		chip->ops->clk_enable(chip, false);
+}
+
 struct tis_vendor_timeout_override {
 	u32 did_vid;
 	unsigned long timeout_us[4];
@@ -842,6 +920,7 @@ static const struct tpm_class_ops tpm_tis = {
 	.send = tpm_tis_send,
 	.cancel = tpm_tis_ready,
 	.update_timeouts = tpm_tis_update_timeouts,
+	.update_durations = tpm_tis_update_durations,
 	.req_complete_mask = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
 	.req_complete_val = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
 	.req_canceled = tpm_tis_req_canceled,
-- 
2.21.0

Re: [PATCH v4 2/3] tpm: provide a way to override the chip returned durations

[Jarkko Sakkinen]

On Mon, 2019-09-02 at 07:27 -0700, Jerry Snitselaar wrote:
> Patch adds method ->update_durations to override returned
> durations in case TPM chip misbehaves for TPM 1.2 drivers.
> 
> Cc: Peter Huewe <peterhuewe@gmx.de>
> Cc: Jason Gunthorpe <jgg@ziepe.ca>
> Signed-off-by: Alexey Klimov <aklimov@redhat.com>
> Signed-off-by: Jerry Snitselaar <jsnitsel@redhat.com>
> Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>

Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> (!update_durations path)

/Jarkko

Re: [PATCH v4 3/3] tpm_tis: override durations for STM tpm with firmware 1.2.8.28

[Jarkko Sakkinen]

On Mon, 2019-09-02 at 07:27 -0700, Jerry Snitselaar wrote:
> There was revealed a bug in the STM TPM chipset used in Dell R415s.
> Bug is observed so far only on chipset firmware 1.2.8.28
> (1.2 TPM, device-id 0x0, rev-id 78). After some number of
> operations chipset hangs and stays in inconsistent state:
> 
> tpm_tis 00:09: Operation Timed out
> tpm_tis 00:09: tpm_transmit: tpm_send: error -5
> 
> Durations returned by the chip are the same like on other
> firmware revisions but apparently with specifically 1.2.8.28 fw
> durations should be reset to 2 minutes to enable tpm chip work
> properly. No working way of updating firmware was found.
> 
> This patch adds implementation of ->update_durations method
> that matches only STM devices with specific firmware version.
> 
> Cc: Peter Huewe <peterhuewe@gmx.de>
> Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
> Cc: Jason Gunthorpe <jgg@ziepe.ca>
> Signed-off-by: Alexey Klimov <aklimov@redhat.com>
> Signed-off-by: Jerry Snitselaar <jsnitsel@redhat.com>
> Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>

Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> (!update_durations path)

/Jarkko

Re: [PATCH v4 0/4] tpm: add update_durations class op to allow override of chip supplied values

[Jerry Snitselaar]

On Mon Sep 02 19, Jerry Snitselaar wrote:
>We've run into a case where a customer has an STM TPM 1.2 chip
>(version 1.2.8.28), that is getting into an inconsistent state and
>they end up getting tpm transmit errors.  In really old tpm code this
>wasn't seen because the code that grabbed the duration values from the
>chip could fail silently, and would proceed to just use default values
>and move forward. More recent code though successfully gets the
>duration values from the chip, and using those values this particular
>chip version gets into the state seen by the customer.
>
>The idea with this patchset is to provide a facility like the
>update_timeouts operation to allow the override of chip supplied
>values.
>
>changes from v3:
>    * Assign value to version when tpm1_getcap is successful for TPM 1.1 device
>      not when it fails.
>
>changes from v2:
>    * Added patch 1/3
>    * Rework tpm_tis_update_durations to make use of new version structs
>      and pull tpm1_getcap calls out of loop.
>
>changes from v1:
>    * Remove unneeded newline
>    * Formatting cleanups
>    * Change tpm_tis_update_durations to be a void function, and
>      use chip->duration_adjusted to track whether adjustment was
>      made.
>
>Jarkko Sakkinen (1):
>      tpm: Remove duplicate code from caps_show() in tpm-sysfs.c
>
>Jerry Snitselaar (2):
>      tpm: provide a way to override the chip returned durations
>      tpm_tis: override durations for STM tpm with firmware 1.2.8.28
>
>

Anyone else have any feedback on this patchset?

Re: [PATCH v4 0/4] tpm: add update_durations class op to allow override of chip supplied values

[Jarkko Sakkinen]

On Sat, Sep 28, 2019 at 10:45:43AM -0700, Jerry Snitselaar wrote:
> On Mon Sep 02 19, Jerry Snitselaar wrote:
> > We've run into a case where a customer has an STM TPM 1.2 chip
> > (version 1.2.8.28), that is getting into an inconsistent state and
> > they end up getting tpm transmit errors.  In really old tpm code this
> > wasn't seen because the code that grabbed the duration values from the
> > chip could fail silently, and would proceed to just use default values
> > and move forward. More recent code though successfully gets the
> > duration values from the chip, and using those values this particular
> > chip version gets into the state seen by the customer.
> > 
> > The idea with this patchset is to provide a facility like the
> > update_timeouts operation to allow the override of chip supplied
> > values.
> > 
> > changes from v3:
> >    * Assign value to version when tpm1_getcap is successful for TPM 1.1 device
> >      not when it fails.
> > 
> > changes from v2:
> >    * Added patch 1/3
> >    * Rework tpm_tis_update_durations to make use of new version structs
> >      and pull tpm1_getcap calls out of loop.
> > 
> > changes from v1:
> >    * Remove unneeded newline
> >    * Formatting cleanups
> >    * Change tpm_tis_update_durations to be a void function, and
> >      use chip->duration_adjusted to track whether adjustment was
> >      made.
> > 
> > Jarkko Sakkinen (1):
> >      tpm: Remove duplicate code from caps_show() in tpm-sysfs.c
> > 
> > Jerry Snitselaar (2):
> >      tpm: provide a way to override the chip returned durations
> >      tpm_tis: override durations for STM tpm with firmware 1.2.8.28
> > 
> > 
> 
> Anyone else have any feedback on this patchset?

Thanks for reminding. I'll put this to my master soonish.

/Jarkko

Re: [PATCH v4 0/4] tpm: add update_durations class op to allow override of chip supplied values

[Jarkko Sakkinen]

On Mon, Sep 02, 2019 at 07:27:32AM -0700, Jerry Snitselaar wrote:
> We've run into a case where a customer has an STM TPM 1.2 chip
> (version 1.2.8.28), that is getting into an inconsistent state and
> they end up getting tpm transmit errors.  In really old tpm code this
> wasn't seen because the code that grabbed the duration values from the
> chip could fail silently, and would proceed to just use default values
> and move forward. More recent code though successfully gets the
> duration values from the chip, and using those values this particular
> chip version gets into the state seen by the customer.
> 
> The idea with this patchset is to provide a facility like the
> update_timeouts operation to allow the override of chip supplied
> values.
> 
> changes from v3:
>     * Assign value to version when tpm1_getcap is successful for TPM 1.1 device
>       not when it fails.
> 
> changes from v2:
>     * Added patch 1/3
>     * Rework tpm_tis_update_durations to make use of new version structs
>       and pull tpm1_getcap calls out of loop.
> 
> changes from v1:
>     * Remove unneeded newline
>     * Formatting cleanups
>     * Change tpm_tis_update_durations to be a void function, and
>       use chip->duration_adjusted to track whether adjustment was
>       made.
> 
> Jarkko Sakkinen (1):
>       tpm: Remove duplicate code from caps_show() in tpm-sysfs.c
> 
> Jerry Snitselaar (2):
>       tpm: provide a way to override the chip returned durations
>       tpm_tis: override durations for STM tpm with firmware 1.2.8.28
> 
> 

I applied to my master branch.

Probably hard to get wide testing given the "niche" case when the
issue happens. Should be sufficient that the commonc case still
works.

/Jarkko

Re: [PATCH v4 0/4] tpm: add update_durations class op to allow override of chip supplied values

[Jerry Snitselaar]

On Wed Oct 02 19, Jarkko Sakkinen wrote:
>On Mon, Sep 02, 2019 at 07:27:32AM -0700, Jerry Snitselaar wrote:
>> We've run into a case where a customer has an STM TPM 1.2 chip
>> (version 1.2.8.28), that is getting into an inconsistent state and
>> they end up getting tpm transmit errors.  In really old tpm code this
>> wasn't seen because the code that grabbed the duration values from the
>> chip could fail silently, and would proceed to just use default values
>> and move forward. More recent code though successfully gets the
>> duration values from the chip, and using those values this particular
>> chip version gets into the state seen by the customer.
>>
>> The idea with this patchset is to provide a facility like the
>> update_timeouts operation to allow the override of chip supplied
>> values.
>>
>> changes from v3:
>>     * Assign value to version when tpm1_getcap is successful for TPM 1.1 device
>>       not when it fails.
>>
>> changes from v2:
>>     * Added patch 1/3
>>     * Rework tpm_tis_update_durations to make use of new version structs
>>       and pull tpm1_getcap calls out of loop.
>>
>> changes from v1:
>>     * Remove unneeded newline
>>     * Formatting cleanups
>>     * Change tpm_tis_update_durations to be a void function, and
>>       use chip->duration_adjusted to track whether adjustment was
>>       made.
>>
>> Jarkko Sakkinen (1):
>>       tpm: Remove duplicate code from caps_show() in tpm-sysfs.c
>>
>> Jerry Snitselaar (2):
>>       tpm: provide a way to override the chip returned durations
>>       tpm_tis: override durations for STM tpm with firmware 1.2.8.28
>>
>>
>
>I applied to my master branch.
>
>Probably hard to get wide testing given the "niche" case when the
>issue happens. Should be sufficient that the commonc case still
>works.
>
>/Jarkko

Yeah, it is a pain. The people with the problem systems tested an
earlier version of Alexey's patches. I have a system with a different
rev STM device, so I did some testing with a modified patch that keyed
off that revision, but it will be hard to get it wide exposure.

Re: [PATCH v4 0/4] tpm: add update_durations class op to allow override of chip supplied values

[Jarkko Sakkinen]

On Thu, Oct 03, 2019 at 09:55:51AM -0700, Jerry Snitselaar wrote:
> On Wed Oct 02 19, Jarkko Sakkinen wrote:
> > On Mon, Sep 02, 2019 at 07:27:32AM -0700, Jerry Snitselaar wrote:
> > > We've run into a case where a customer has an STM TPM 1.2 chip
> > > (version 1.2.8.28), that is getting into an inconsistent state and
> > > they end up getting tpm transmit errors.  In really old tpm code this
> > > wasn't seen because the code that grabbed the duration values from the
> > > chip could fail silently, and would proceed to just use default values
> > > and move forward. More recent code though successfully gets the
> > > duration values from the chip, and using those values this particular
> > > chip version gets into the state seen by the customer.
> > > 
> > > The idea with this patchset is to provide a facility like the
> > > update_timeouts operation to allow the override of chip supplied
> > > values.
> > > 
> > > changes from v3:
> > >     * Assign value to version when tpm1_getcap is successful for TPM 1.1 device
> > >       not when it fails.
> > > 
> > > changes from v2:
> > >     * Added patch 1/3
> > >     * Rework tpm_tis_update_durations to make use of new version structs
> > >       and pull tpm1_getcap calls out of loop.
> > > 
> > > changes from v1:
> > >     * Remove unneeded newline
> > >     * Formatting cleanups
> > >     * Change tpm_tis_update_durations to be a void function, and
> > >       use chip->duration_adjusted to track whether adjustment was
> > >       made.
> > > 
> > > Jarkko Sakkinen (1):
> > >       tpm: Remove duplicate code from caps_show() in tpm-sysfs.c
> > > 
> > > Jerry Snitselaar (2):
> > >       tpm: provide a way to override the chip returned durations
> > >       tpm_tis: override durations for STM tpm with firmware 1.2.8.28
> > > 
> > > 
> > 
> > I applied to my master branch.
> > 
> > Probably hard to get wide testing given the "niche" case when the
> > issue happens. Should be sufficient that the commonc case still
> > works.
> > 
> > /Jarkko
> 
> Yeah, it is a pain. The people with the problem systems tested an
> earlier version of Alexey's patches. I have a system with a different
> rev STM device, so I did some testing with a modified patch that keyed
> off that revision, but it will be hard to get it wide exposure.

I think this is sufficient for me as it

1. Fixes the issue.
2. I've verified that it doesn't break systems that don't have the
   issue

The worst case scenario is that you break something that is broken
already...

/Jarkko