From: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
To: Peter Huewe <peterhuewe@gmx.de>
Cc: linux-security-module@vger.kernel.org,
Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>,
stable@vger.kernel.org, Marcel Selhorst <tpmdd@selhorst.net>,
Jason Gunthorpe <jgunthorpe@obsidianresearch.com>,
tpmdd-devel@lists.sourceforge.net (moderated list:TPM DEVICE
DRIVER), linux-kernel@vger.kernel.org (open list)
Subject: [PATCH 1/3] tpm_crb: fix crb_req_canceled behavior
Date: Wed, 8 Jun 2016 02:02:00 +0300 [thread overview]
Message-ID: <1465340522-1112-2-git-send-email-jarkko.sakkinen@linux.intel.com> (raw)
In-Reply-To: <1465340522-1112-1-git-send-email-jarkko.sakkinen@linux.intel.com>
The req_canceled() callback is used by tpm_transmit() periodically to
check whether the request has been canceled while it is receiving a
response from the TPM.
The TPM_CRB_CTRL_CANCEL register was cleared already in the crb_cancel
callback, which has two consequences:
* Cancel might not happen.
* req_canceled() always returns zero.
A better place to clear the register is when starting to send a new
command. The behavior of TPM_CRB_CTRL_CANCEL is described in the
section 5.5.3.6 of the PTP specification.
CC: stable@vger.kernel.org
Fixes: 30fc8d138e91 ("tpm: TPM 2.0 CRB Interface")
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
---
drivers/char/tpm/tpm_crb.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/char/tpm/tpm_crb.c b/drivers/char/tpm/tpm_crb.c
index 1547636..b4d46ae 100644
--- a/drivers/char/tpm/tpm_crb.c
+++ b/drivers/char/tpm/tpm_crb.c
@@ -142,6 +142,11 @@ static int crb_send(struct tpm_chip *chip, u8 *buf, size_t len)
struct crb_priv *priv = dev_get_drvdata(&chip->dev);
int rc = 0;
+ /* Zero the cancel register so that the next command will not get
+ * canceled.
+ */
+ iowrite32(0, &priv->cca->cancel);
+
if (len > ioread32(&priv->cca->cmd_size)) {
dev_err(&chip->dev,
"invalid command count value %x %zx\n",
@@ -175,8 +180,6 @@ static void crb_cancel(struct tpm_chip *chip)
if ((priv->flags & CRB_FL_ACPI_START) && crb_do_acpi_start(chip))
dev_err(&chip->dev, "ACPI Start failed\n");
-
- iowrite32(0, &priv->cca->cancel);
}
static bool crb_req_canceled(struct tpm_chip *chip, u8 status)
--
2.7.4
next prev parent reply other threads:[~2016-06-07 23:02 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-06-07 23:01 [PATCH 0/3] Runtime PM for TPM2 CRB chips Jarkko Sakkinen
2016-06-07 23:02 ` Jarkko Sakkinen [this message]
2016-06-07 23:02 ` [PATCH 2/3] tpm, tpm_crb: remove wmb()'s Jarkko Sakkinen
2016-06-07 23:02 ` [PATCH 3/3] tpm, tpm_crb: runtime power management Jarkko Sakkinen
2016-06-14 13:14 ` [tpmdd-devel] " Tomas Winkler
2016-06-16 19:57 ` Jarkko Sakkinen
2016-06-16 20:18 ` Jarkko Sakkinen
2016-06-16 20:26 ` Tomas Winkler
2016-06-16 20:44 ` Jason Gunthorpe
2016-06-16 21:29 ` Jarkko Sakkinen
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1465340522-1112-2-git-send-email-jarkko.sakkinen@linux.intel.com \
--to=jarkko.sakkinen@linux.intel.com \
--cc=jgunthorpe@obsidianresearch.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-security-module@vger.kernel.org \
--cc=peterhuewe@gmx.de \
--cc=stable@vger.kernel.org \
--cc=tpmdd-devel@lists.sourceforge.net \
--cc=tpmdd@selhorst.net \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).