Messages in this thread | | | Subject | Re: [PATCH 3/3] tpm: ibmvtpm: Add support for TPM 2 | From | Stefan Berger <> | Date | Thu, 13 Feb 2020 14:15:03 -0500 |
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On 2/13/20 2:11 PM, Jason Gunthorpe wrote: > On Thu, Feb 13, 2020 at 02:04:12PM -0500, Stefan Berger wrote: >> On 2/13/20 1:35 PM, Jason Gunthorpe wrote: >>> On Thu, Feb 13, 2020 at 01:20:12PM -0500, Stefan Berger wrote: >>> >>>> I don't want side effects for the TPM 1.2 case here, so I am only modifying >>>> the flag for the case where the new TPM 2 is being used. Here's the code >>>> where it shows the effect. >>> I'm surprised this driver is using AUTO_STARTUP, it was intended for >>> embedded cases where their is no firmware to boot the TPM. >> The TIS is also using it on any device. > TIS is a generic driver, and can run on TPMs without firmware > support. It doesn't know either way
The following drivers are all using it:
drivers/char/tpm/st33zp24/st33zp24.c, line 493 drivers/char/tpm/tpm-interface.c, line 374 drivers/char/tpm/tpm_crb.c, line 421 drivers/char/tpm/tpm_ftpm_tee.c, line 184 drivers/char/tpm/tpm_i2c_atmel.c, line 139 drivers/char/tpm/tpm_i2c_infineon.c, line 602 drivers/char/tpm/tpm_i2c_nuvoton.c, line 465 drivers/char/tpm/tpm_tis_core.c, line 917 drivers/char/tpm/tpm_vtpm_proxy.c, line 435
https://elixir.bootlin.com/linux/latest/ident/TPM_OPS_AUTO_STARTUP
> >>> Chips using AUTO_STARTUP are basically useless for PCRs/etc. >>> >>> I'd expect somthing called vtpm to have been started and PCRs working >>> before Linux is started?? >> Yes, there's supposed to be firmware. >> >> I only see one caller to tpm2_get_cc_attrs_tbl(chip), which is necessary to >> call. This caller happens to be in tpm2_auto_startup. > That seems to be a mistake, proper startup of the driver should never > require auto_startup.
Is this IBM vTPM driver special that it should do things differently than all those drivers listed above? From looking at the code is seems it is to be set for the TPM 2.0 case.
Stefan
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