From: Amir Mizinski <[email protected]>
Using this function while reading/writing data resulted in an aborted
operation.
After investigating the issue according to the TCG TPM Profile (PTP)
Specifications, I found that "request to cancel" should occur only if
TPM_STS.commandReady bit is lit.
Note that i couldn't find a case where the present condition
(in the linux kernel) is valid, so I'm removing the case for
"TPM_VID_WINBOND" since we have no need for it.
Also, the default comparison is wrong. Only cmdReady bit needs to be
compared instead of the full lower status register byte.
Fixes: 1f866057291f (tpm: Fix cancellation of TPM commands (polling mode))
Signed-off-by: Amir Mizinski <[email protected]>
---
drivers/char/tpm/tpm_tis_core.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c
index b34e59b..4145758 100644
--- a/drivers/char/tpm/tpm_tis_core.c
+++ b/drivers/char/tpm/tpm_tis_core.c
@@ -650,13 +650,11 @@ static bool tpm_tis_req_canceled(struct tpm_chip *chip, u8 status)
struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
switch (priv->manufacturer_id) {
- case TPM_VID_WINBOND:
- return ((status == TPM_STS_VALID) ||
- (status == (TPM_STS_VALID | TPM_STS_COMMAND_READY)));
case TPM_VID_STM:
return (status == (TPM_STS_VALID | TPM_STS_COMMAND_READY));
default:
- return (status == TPM_STS_COMMAND_READY);
+ return ((status & TPM_STS_COMMAND_READY) ==
+ TPM_STS_COMMAND_READY);
}
}
--
2.7.4
On Thu, 2021-08-26 at 14:19 +0300, [email protected] wrote:
> From: Amir Mizinski <[email protected]>
>
> Using this function while reading/writing data resulted in an aborted
> operation.
"Using <the function name>...". Also what is "aborted operation"?
Please say the exact thing instead of absractions.
/Jarkko