| Message ID | 77221b3a-40b3-f5db-e821-10e258f869dc@maciej.szmigiero.name |
|---|---|
| State | New |
| Headers | show |
On Wed, Jan 04, 2017 at 06:47:52PM +0100, Maciej S. Szmigiero wrote: > (Resending as no reply received, this time with CCs to TPM maintainers and > author of the original commit). > > Hi all, > > Commit 1107d065fdf1 (tpm_tis: Introduce intermediate layer for TPM access) > broke TPM support on ThinkPad X61S (and likely also on other machines which > use TPMs with a static burst count). > > It looks like tpm_tis code before this commit had spun on TPM_STS_DATA_AVAIL | > TPM_STS_VALID status bits in the read case and TPM_STS_VALID in the write case > when it got a zero burst count. > > I have attached a patch against current code (linux-tpmdd tree) that brings > back this old behavior. > With this patch the TPM works again on X61S. > However, somebody with more TPM experience should comment whether such behavior > was OK or the change brought by commit 1107d065fdf1 was intentional. > > Maciej Szmigiero For me this commit makes perfect sense. Could you do the following things: 1. Clean up the description a little bit 2. Add your Signed-off-by tag. 3. Add "Cc: stable@vger.kernel.org" tag right after your signed-off-by. 4. CC this linux-security-module@vger.kernel.org, stable@vger.kernel.org, linux-kernel@vger.kernel.org. 5. Run scripts/checkpatch.pl 6. Re-send for review. Thanks for fixing the issue. Keep up the good work! /Jarkko > > diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c > index 7993678954a2..72d365db7c61 100644 > --- a/drivers/char/tpm/tpm_tis_core.c > +++ b/drivers/char/tpm/tpm_tis_core.c > @@ -188,7 +188,9 @@ static int recv_data(struct tpm_chip *chip, u8 *buf, size_t count) > if (rc < 0) > return rc; > burstcnt = get_burstcount(chip); > - if (burstcnt < 0) { > + if (burstcnt == -EBUSY) > + continue; > + else if (burstcnt < 0) { > dev_err(&chip->dev, "Unable to read burstcount\n"); > return burstcnt; > } > @@ -282,18 +284,20 @@ static int tpm_tis_send_data(struct tpm_chip *chip, u8 *buf, size_t len) > > while (count < len - 1) { > burstcnt = get_burstcount(chip); > - if (burstcnt < 0) { > + if (burstcnt < 0 && burstcnt != -EBUSY) { > dev_err(&chip->dev, "Unable to read burstcount\n"); > rc = burstcnt; > goto out_err; > + } else if (burstcnt > 0) { > + burstcnt = min_t(int, burstcnt, len - count - 1); > + rc = tpm_tis_write_bytes(priv, > + TPM_DATA_FIFO(priv->locality), > + burstcnt, buf + count); > + if (rc < 0) > + goto out_err; > + > + count += burstcnt; > } > - burstcnt = min_t(int, burstcnt, len - count - 1); > - rc = tpm_tis_write_bytes(priv, TPM_DATA_FIFO(priv->locality), > - burstcnt, buf + count); > - if (rc < 0) > - goto out_err; > - > - count += burstcnt; > > if (wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c, > &priv->int_queue, false) < 0) { ------------------------------------------------------------------------------ Developer Access Program for Intel Xeon Phi Processors Access to Intel Xeon Phi processor-based developer platforms. With one year of Intel Parallel Studio XE. Training and support from Colfax. Order your platform today. http://sdm.link/xeonphi
Hi Jarkko, On 09.01.2017 23:09, Jarkko Sakkinen wrote: > On Wed, Jan 04, 2017 at 06:47:52PM +0100, Maciej S. Szmigiero wrote: >> (Resending as no reply received, this time with CCs to TPM maintainers and >> author of the original commit). >> >> Hi all, >> >> Commit 1107d065fdf1 (tpm_tis: Introduce intermediate layer for TPM access) >> broke TPM support on ThinkPad X61S (and likely also on other machines which >> use TPMs with a static burst count). >> >> It looks like tpm_tis code before this commit had spun on TPM_STS_DATA_AVAIL | >> TPM_STS_VALID status bits in the read case and TPM_STS_VALID in the write case >> when it got a zero burst count. >> >> I have attached a patch against current code (linux-tpmdd tree) that brings >> back this old behavior. >> With this patch the TPM works again on X61S. >> However, somebody with more TPM experience should comment whether such behavior >> was OK or the change brought by commit 1107d065fdf1 was intentional. >> > > For me this commit makes perfect sense. Could you do the following things: > > 1. Clean up the description a little bit > 2. Add your Signed-off-by tag. > 3. Add "Cc: stable@vger.kernel.org" tag right after your signed-off-by. > 4. CC this linux-security-module@vger.kernel.org, stable@vger.kernel.org, > linux-kernel@vger.kernel.org. > 5. Run scripts/checkpatch.pl > 6. Re-send for review. Yes, I will respin this as a proper submission, just wanted to make sure that it makes sense to restore the old behavior. > Thanks for fixing the issue. Keep up the good work! Thanks for kind words and all your TPM work! > /Jarkko Maciej ------------------------------------------------------------------------------ Developer Access Program for Intel Xeon Phi Processors Access to Intel Xeon Phi processor-based developer platforms. With one year of Intel Parallel Studio XE. Training and support from Colfax. Order your platform today. http://sdm.link/xeonphi
diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c index 7993678954a2..72d365db7c61 100644 --- a/drivers/char/tpm/tpm_tis_core.c +++ b/drivers/char/tpm/tpm_tis_core.c @@ -188,7 +188,9 @@ static int recv_data(struct tpm_chip *chip, u8 *buf, size_t count) if (rc < 0) return rc; burstcnt = get_burstcount(chip); - if (burstcnt < 0) { + if (burstcnt == -EBUSY) + continue; + else if (burstcnt < 0) { dev_err(&chip->dev, "Unable to read burstcount\n"); return burstcnt; } @@ -282,18 +284,20 @@ static int tpm_tis_send_data(struct tpm_chip *chip, u8 *buf, size_t len) while (count < len - 1) { burstcnt = get_burstcount(chip); - if (burstcnt < 0) { + if (burstcnt < 0 && burstcnt != -EBUSY) { dev_err(&chip->dev, "Unable to read burstcount\n"); rc = burstcnt; goto out_err; + } else if (burstcnt > 0) { + burstcnt = min_t(int, burstcnt, len - count - 1); + rc = tpm_tis_write_bytes(priv, + TPM_DATA_FIFO(priv->locality), + burstcnt, buf + count); + if (rc < 0) + goto out_err; + + count += burstcnt; } - burstcnt = min_t(int, burstcnt, len - count - 1); - rc = tpm_tis_write_bytes(priv, TPM_DATA_FIFO(priv->locality), - burstcnt, buf + count); - if (rc < 0) - goto out_err; - - count += burstcnt; if (wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c, &priv->int_queue, false) < 0) {