| Message ID | 20210531045131.110616-1-jarkko@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | tpm: Replace WARN_ONCE() with dev_err_once() in tpm_tis_status() | expand |
On Mon, May 31, 2021 at 07:51:31AM +0300, Jarkko Sakkinen wrote: > Do not torn down the system when getting invalid status from a TPM chip. > This can happen when panic-on-warn is used. > > In addition, print out the value of TPM_STS.x instead of "invalid > status". In order to get the earlier benefits for forensics, also call > dump_stack(). > > Link: https://lore.kernel.org/keyrings/YKzlTR1AzUigShtZ@kroah.com/ > Fixes: 55707d531af6 ("tpm_tis: Add a check for invalid status") > Cc: stable@vger.kernel.org > Cc: Hans de Goede <hdegoede@redhat.com> > Cc: Greg KH <greg@kroah.com> > Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org> > --- > drivers/char/tpm/tpm_tis_core.c | 11 ++++++++++- > 1 file changed, 10 insertions(+), 1 deletion(-) > > diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c > index 55b9d3965ae1..514a481829c9 100644 > --- a/drivers/char/tpm/tpm_tis_core.c > +++ b/drivers/char/tpm/tpm_tis_core.c > @@ -202,7 +202,16 @@ static u8 tpm_tis_status(struct tpm_chip *chip) > * acquired. Usually because tpm_try_get_ops() hasn't > * been called before doing a TPM operation. > */ > - WARN_ONCE(1, "TPM returned invalid status\n"); > + dev_err_once(&chip->dev, "invalid TPM_STS.x 0x%02x, dumping stack for forensics\n", > + status); > + > + /* > + * Dump stack for forensics, as invalid TPM_STS.x could be > + * potentially triggered by impaired tpm_try_get_ops() or > + * tpm_find_get_ops(). > + */ > + dump_stack(); > + > return 0; > } Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Dear Jarkko, Am 31.05.21 um 06:51 schrieb Jarkko Sakkinen: > Do not torn down the system when getting invalid status from a TPM chip. Nit: Do not *tear* down …? > This can happen when panic-on-warn is used. Hmm, I’d say it works as expected then? Shouldn’t an invalid status of an important device like TPM considered a warning? > In addition, print out the value of TPM_STS.x instead of "invalid > status". In order to get the earlier benefits for forensics, also call > dump_stack(). > > Link: https://lore.kernel.org/keyrings/YKzlTR1AzUigShtZ@kroah.com/ > Fixes: 55707d531af6 ("tpm_tis: Add a check for invalid status") > Cc: stable@vger.kernel.org > Cc: Hans de Goede <hdegoede@redhat.com> > Cc: Greg KH <greg@kroah.com> > Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org> > --- > drivers/char/tpm/tpm_tis_core.c | 11 ++++++++++- > 1 file changed, 10 insertions(+), 1 deletion(-) > > diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c > index 55b9d3965ae1..514a481829c9 100644 > --- a/drivers/char/tpm/tpm_tis_core.c > +++ b/drivers/char/tpm/tpm_tis_core.c > @@ -202,7 +202,16 @@ static u8 tpm_tis_status(struct tpm_chip *chip) > * acquired. Usually because tpm_try_get_ops() hasn't > * been called before doing a TPM operation. > */ > - WARN_ONCE(1, "TPM returned invalid status\n"); > + dev_err_once(&chip->dev, "invalid TPM_STS.x 0x%02x, dumping stack for forensics\n", > + status); > + > + /* > + * Dump stack for forensics, as invalid TPM_STS.x could be > + * potentially triggered by impaired tpm_try_get_ops() or > + * tpm_find_get_ops(). > + */ > + dump_stack(); > + > return 0; > } Kind regards, Paul
On Mon, May 31, 2021 at 07:33:44AM +0200, Paul Menzel wrote: > Dear Jarkko, > > > Am 31.05.21 um 06:51 schrieb Jarkko Sakkinen: > > Do not torn down the system when getting invalid status from a TPM chip. > > Nit: Do not *tear* down …? Oops, a typo, thank you. > > This can happen when panic-on-warn is used. > > Hmm, I’d say it works as expected then? Shouldn’t an invalid status of an > important device like TPM considered a warning? By warning do you mean WARN() or pr_warn()? /Jarkko
diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c index 55b9d3965ae1..514a481829c9 100644 --- a/drivers/char/tpm/tpm_tis_core.c +++ b/drivers/char/tpm/tpm_tis_core.c @@ -202,7 +202,16 @@ static u8 tpm_tis_status(struct tpm_chip *chip) * acquired. Usually because tpm_try_get_ops() hasn't * been called before doing a TPM operation. */ - WARN_ONCE(1, "TPM returned invalid status\n"); + dev_err_once(&chip->dev, "invalid TPM_STS.x 0x%02x, dumping stack for forensics\n", + status); + + /* + * Dump stack for forensics, as invalid TPM_STS.x could be + * potentially triggered by impaired tpm_try_get_ops() or + * tpm_find_get_ops(). + */ + dump_stack(); + return 0; }
Do not torn down the system when getting invalid status from a TPM chip. This can happen when panic-on-warn is used. In addition, print out the value of TPM_STS.x instead of "invalid status". In order to get the earlier benefits for forensics, also call dump_stack(). Link: https://lore.kernel.org/keyrings/YKzlTR1AzUigShtZ@kroah.com/ Fixes: 55707d531af6 ("tpm_tis: Add a check for invalid status") Cc: stable@vger.kernel.org Cc: Hans de Goede <hdegoede@redhat.com> Cc: Greg KH <greg@kroah.com> Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org> --- drivers/char/tpm/tpm_tis_core.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-)