On Wed, Apr 02, 2025 at 06:45:40PM +0100, Jonathan McDowell wrote: > On Wed, Apr 02, 2025 at 07:21:30PM +0200, Michal Suchanek wrote: > > With some Infineon chips the timeouts in tpm_tis_send_data (both B and > > C) can reach up to about 2250 ms. > > > > Extend the timeout duration to accommodate this. > > The problem here is the bump of timeout_c is going to interact poorly with > the Infineon errata workaround, as now we'll wait 4s instead of 200ms to > detect the stuck status change.
Yes, that's problematic. Is it possible to detect the errata by anything other than waiting for the timeout to expire? > > (Also shouldn't timeout_c already end up as 750ms, as it's > max(TIS_SHORT_TIMEOUT, TPM2_TIMEOUT_C), and TIS_SHORT_TIMEOUT is 750 vs 200 > for TPM2_TIMEOUT_C? That doesn't seem to be borne out by your logs, nor my > results.) Indeed, it should be 750ms but the logs show 200ms. I do not see where it could get reduced, nor any significan difference between the mainline code and the kernel I am using in this area. Thanks Michal > > > Link: > > https://lore.kernel.org/linux-integrity/z5pi07m0muapy...@kitsune.suse.cz/ > > Signed-off-by: Michal Suchanek <msucha...@suse.de> > > --- > > An alternative would be to add an entry to vendor_timeout_overrides but > > I do not know how to determine the chip IDs to put into this table. > > --- > > drivers/char/tpm/tpm_tis_core.h | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/char/tpm/tpm_tis_core.h > > b/drivers/char/tpm/tpm_tis_core.h > > index 970d02c337c7..1ff565be2175 100644 > > --- a/drivers/char/tpm/tpm_tis_core.h > > +++ b/drivers/char/tpm/tpm_tis_core.h > > @@ -54,7 +54,7 @@ enum tis_int_flags { > > enum tis_defaults { > > TIS_MEM_LEN = 0x5000, > > TIS_SHORT_TIMEOUT = 750, /* ms */ > > - TIS_LONG_TIMEOUT = 2000, /* 2 sec */ > > + TIS_LONG_TIMEOUT = 4000, /* 2 sec */ > > TIS_TIMEOUT_MIN_ATML = 14700, /* usecs */ > > TIS_TIMEOUT_MAX_ATML = 15000, /* usecs */ > > }; > > @@ -64,7 +64,7 @@ enum tis_defaults { > > */ > > #define TIS_TIMEOUT_A_MAX max_t(int, TIS_SHORT_TIMEOUT, TPM2_TIMEOUT_A) > > #define TIS_TIMEOUT_B_MAX max_t(int, TIS_LONG_TIMEOUT, TPM2_TIMEOUT_B) > > -#define TIS_TIMEOUT_C_MAX max_t(int, TIS_SHORT_TIMEOUT, TPM2_TIMEOUT_C) > > +#define TIS_TIMEOUT_C_MAX max_t(int, TIS_LONG_TIMEOUT, TPM2_TIMEOUT_C) > > #define TIS_TIMEOUT_D_MAX max_t(int, TIS_SHORT_TIMEOUT, TPM2_TIMEOUT_D) > > > > #define TPM_ACCESS(l) (0x0000 | ((l) << 12)) > > -- > > 2.47.1 > > > > J. > > -- > ... "Tom's root boot is the Linux world equivalent of a 'get out of jail > free' card. The man is a *hero*." -- Simon Brooke, ucol.
