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tpm2: add longer timeouts for creation commands.
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TPM2_CC_Create(0x153) and TPM2_CC_CreatePrimary (0x131) involve generation
of crypto keys which can be a computationally intensive task. The timeout
is set to 3min. Rather than increasing default timeout a new constant is
added, to not stall for too long on regular commands failures.

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
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tomasbw authored and Jarkko Sakkinen committed Mar 23, 2018
1 parent 09b17f3 commit 076d356
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Showing 3 changed files with 26 additions and 13 deletions.
3 changes: 3 additions & 0 deletions drivers/char/tpm/tpm-interface.c
Original file line number Diff line number Diff line change
Expand Up @@ -696,6 +696,8 @@ int tpm_get_timeouts(struct tpm_chip *chip)
msecs_to_jiffies(TPM2_DURATION_MEDIUM);
chip->duration[TPM_LONG] =
msecs_to_jiffies(TPM2_DURATION_LONG);
chip->duration[TPM_LONG_LONG] =
msecs_to_jiffies(TPM2_DURATION_LONG_LONG);

chip->flags |= TPM_CHIP_FLAG_HAVE_TIMEOUTS;
return 0;
Expand Down Expand Up @@ -784,6 +786,7 @@ int tpm_get_timeouts(struct tpm_chip *chip)
usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_medium));
chip->duration[TPM_LONG] =
usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_long));
chip->duration[TPM_LONG_LONG] = 0; /* not used under 1.2 */

/* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
* value wrong and apparently reports msecs rather than usecs. So we
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28 changes: 18 additions & 10 deletions drivers/char/tpm/tpm.h
Original file line number Diff line number Diff line change
Expand Up @@ -67,7 +67,9 @@ enum tpm_duration {
TPM_SHORT = 0,
TPM_MEDIUM = 1,
TPM_LONG = 2,
TPM_LONG_LONG = 3,
TPM_UNDEFINED,
TPM_NUM_DURATIONS = TPM_UNDEFINED,
};

#define TPM_WARN_RETRY 0x800
Expand All @@ -79,15 +81,20 @@ enum tpm_duration {
#define TPM_HEADER_SIZE 10

enum tpm2_const {
TPM2_PLATFORM_PCR = 24,
TPM2_PCR_SELECT_MIN = ((TPM2_PLATFORM_PCR + 7) / 8),
TPM2_TIMEOUT_A = 750,
TPM2_TIMEOUT_B = 2000,
TPM2_TIMEOUT_C = 200,
TPM2_TIMEOUT_D = 30,
TPM2_DURATION_SHORT = 20,
TPM2_DURATION_MEDIUM = 750,
TPM2_DURATION_LONG = 2000,
TPM2_PLATFORM_PCR = 24,
TPM2_PCR_SELECT_MIN = ((TPM2_PLATFORM_PCR + 7) / 8),
};

enum tpm2_timeouts {
TPM2_TIMEOUT_A = 750,
TPM2_TIMEOUT_B = 2000,
TPM2_TIMEOUT_C = 200,
TPM2_TIMEOUT_D = 30,
TPM2_DURATION_SHORT = 20,
TPM2_DURATION_MEDIUM = 750,
TPM2_DURATION_LONG = 2000,
TPM2_DURATION_LONG_LONG = 300000,
TPM2_DURATION_DEFAULT = 120000,
};

enum tpm2_structures {
Expand Down Expand Up @@ -123,6 +130,7 @@ enum tpm2_algorithms {

enum tpm2_command_codes {
TPM2_CC_FIRST = 0x011F,
TPM2_CC_CREATE_PRIMARY = 0x0131,
TPM2_CC_SELF_TEST = 0x0143,
TPM2_CC_STARTUP = 0x0144,
TPM2_CC_SHUTDOWN = 0x0145,
Expand Down Expand Up @@ -227,7 +235,7 @@ struct tpm_chip {
unsigned long timeout_c; /* jiffies */
unsigned long timeout_d; /* jiffies */
bool timeout_adjusted;
unsigned long duration[3]; /* jiffies */
unsigned long duration[TPM_NUM_DURATIONS]; /* jiffies */
bool duration_adjusted;

struct dentry *bios_dir[TPM_NUM_EVENT_LOG_FILES];
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8 changes: 5 additions & 3 deletions drivers/char/tpm/tpm2-cmd.c
Original file line number Diff line number Diff line change
Expand Up @@ -90,6 +90,8 @@ static struct tpm2_hash tpm2_hash_map[] = {
* of time the chip could take to return the result. The values
* of the SHORT, MEDIUM, and LONG durations are taken from the
* PC Client Profile (PTP) specification.
* LONG_LONG is for commands that generates keys which empirically
* takes longer time on some systems.
*/
static const u8 tpm2_ordinal_duration[TPM2_CC_LAST - TPM2_CC_FIRST + 1] = {
TPM_UNDEFINED, /* 11F */
Expand All @@ -110,7 +112,7 @@ static const u8 tpm2_ordinal_duration[TPM2_CC_LAST - TPM2_CC_FIRST + 1] = {
TPM_UNDEFINED, /* 12e */
TPM_UNDEFINED, /* 12f */
TPM_UNDEFINED, /* 130 */
TPM_UNDEFINED, /* 131 */
TPM_LONG_LONG, /* 131 */
TPM_UNDEFINED, /* 132 */
TPM_UNDEFINED, /* 133 */
TPM_UNDEFINED, /* 134 */
Expand Down Expand Up @@ -144,7 +146,7 @@ static const u8 tpm2_ordinal_duration[TPM2_CC_LAST - TPM2_CC_FIRST + 1] = {
TPM_UNDEFINED, /* 150 */
TPM_UNDEFINED, /* 151 */
TPM_UNDEFINED, /* 152 */
TPM_UNDEFINED, /* 153 */
TPM_LONG_LONG, /* 153 */
TPM_UNDEFINED, /* 154 */
TPM_UNDEFINED, /* 155 */
TPM_UNDEFINED, /* 156 */
Expand Down Expand Up @@ -821,7 +823,7 @@ unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal)
duration = chip->duration[index];

if (duration <= 0)
duration = 2 * 60 * HZ;
duration = msecs_to_jiffies(TPM2_DURATION_DEFAULT);

return duration;
}
Expand Down

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