---
v3:
- Please test this too ;-) I did quick testing only.
- Fixed the reported glitches and mistakes.
v2:
- Followed Mimi's suggestions.
---
 .../admin-guide/kernel-parameters.txt         |  9 ++++
 drivers/char/tpm/tpm-buf.c                    | 20 ++++++++
 drivers/char/tpm/tpm2-cmd.c                   | 30 ++++++++---
 drivers/char/tpm/tpm2-sessions.c              | 51 ++++++++++---------
 include/linux/tpm.h                           |  3 ++
 5 files changed, 82 insertions(+), 31 deletions(-)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 1666576acc0e..7107ad322b2e 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt

@@ -6727,6 +6727,15 @@
 	torture.verbose_sleep_duration= [KNL]
 			Duration of each verbose-printk() sleep in jiffies.
 
+	tpm.disable_pcr_integrity_protection= [HW,TPM]

+			Do not protect PCR registers from unintended physical
+			access, or interposers in the bus by the means of
+			having an integrity protected session wrapped around
+			TPM2_PCR_Extend command. Consider this in a situation
+			where TPM is heavily utilized by IMA, thus protection
+			causing a major performance hit, and the space where
+			machines are deployed is by other means guarded.
+
 	tpm_suspend_pcr=[HW,TPM]
 			Format: integer pcr id
 			Specify that at suspend time, the tpm driver

diff --git a/drivers/char/tpm/tpm-buf.c b/drivers/char/tpm/tpm-buf.c
index cad0048bcc3c..e49a19fea3bd 100644
--- a/drivers/char/tpm/tpm-buf.c
+++ b/drivers/char/tpm/tpm-buf.c

@@ -146,6 +146,26 @@ void tpm_buf_append_u32(struct tpm_buf *buf, const u32 value)
 }
 EXPORT_SYMBOL_GPL(tpm_buf_append_u32);
 
+/**
+ * tpm_buf_append_handle() - Add a handle
+ * @chip:	&tpm_chip instance
+ * @buf:	&tpm_buf instance
+ * @handle:	a TPM object handle
+ *
+ * Add a handle to the buffer, and increase the count tracking the number of
+ * handles in the command buffer. Works only for command buffers.
+ */
+void tpm_buf_append_handle(struct tpm_chip *chip, struct tpm_buf *buf, u32 handle)
+{
+	if (buf->flags & TPM_BUF_TPM2B) {
+		dev_err(&chip->dev, "Invalid buffer type (TPM2B)\n");
+		return;
+	}
+
+	tpm_buf_append_u32(buf, handle);
+	buf->handles++;
+}
+
 /**
  * tpm_buf_read() - Read from a TPM buffer
  * @buf:	&tpm_buf instance

diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index 1e856259219e..dfdcbd009720 100644
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c

@@ -14,6 +14,10 @@
 #include "tpm.h"
 #include <crypto/hash_info.h>
 
+static bool disable_pcr_integrity;
+module_param(disable_pcr_integrity, bool, 0444);
+MODULE_PARM_DESC(disable_pcr_integrity, "Disable integrity protection of TPM2_PCR_Extend");

+
 static struct tpm2_hash tpm2_hash_map[] = {
 	{HASH_ALGO_SHA1, TPM_ALG_SHA1},
 	{HASH_ALGO_SHA256, TPM_ALG_SHA256},

@@ -232,18 +236,26 @@ int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,