optee-based efi runtime variable service on TI j784s4 platforms
Enric Balletbo i Serra
eballetb at redhat.com
Mon Nov 11 06:13:04 PST 2024
Hi,
Thanks a lot for your support.
On Mon, Nov 11, 2024 at 12:01 PM Ilias Apalodimas
<ilias.apalodimas at linaro.org> wrote:
>
> On Mon, 11 Nov 2024 at 10:21, Enric Balletbo i Serra
> <eballetb at redhat.com> wrote:
> >
> > Hi Ilias,
> >
> > On Sat, Nov 9, 2024 at 1:31 AM Ilias Apalodimas
> > <ilias.apalodimas at linaro.org> wrote:
> > >
> > > On Fri, 8 Nov 2024 at 23:11, Enric Balletbo i Serra <eballetb at redhat.com> wrote:
> > > >
> > > > Hi Ilias,
> > > >
> > > > Thanks for your quick answer.
> > > >
> > > > On Fri, Nov 8, 2024 at 4:48 PM Ilias Apalodimas
> > > > <ilias.apalodimas at linaro.org> wrote:
> > > > >
> > > > > Hi Enric,
> > > > >
> > > > > On Fri, 8 Nov 2024 at 12:26, Enric Balletbo i Serra <eballetb at redhat.com> wrote:
> > > > > >
> > > > > > Hi all,
> > > > > >
> > > > > > I'm looking for any advice/clue to help me to progress on enabling
> > > > > > TEE-base EFI Runtime Variable Service on TI a j784s4 platforms.
> > > > > >
> > > > > > I basically followed the steps described in u-boot documentation [1],
> > > > > > I enabled some debugging messages but I think I'm at the point that
> > > > > > the problem might be in the StandaloneMM application, and I'm not sure
> > > > > > how to debug it.
> > > > > >
> > > > > > What I see is that when I run the tee-supplicant daemon, it looks like
> > > > > > the tee_client_open_session() call loops forever and the tee_stmm_efi
> > > > > > driver never ends to probe.
> > > > > >
> > > > > > With debug enabled I got the following messages.
> > > > >
> > > > > I assume reading and storing variables already works in U-Boot right?
> > > > >
> > > >
> > > > Reading and storing variables to the RPMB partition in U-Boot works,
> > > > that's using the mmc rpmb command from u-boot,
> > >
> > > Are you talking about env variables? Perhaps you store them in the mmc
> > > and not the RPMB partition?
> > > There's some information here [0]
> > >
> > > > But setting
> > > > CONFIG_EFI_MM_COMM_TEE=y in u-boot I end with a similar behaviour
> > > > (although I'm not able to debug at u-boot level) What I see is that
> > > > u-boot gets stuck
> > > > when bootefi bootmgr is invoqued. I can also reproduce the issue with
> > > > bootefi hello.
> > > >
> > > > => run bootcmd
> > > > Scanning for bootflows in all bootdevs
> > > > Seq Method State Uclass Part Name Filename
> > > > --- ----------- ------ -------- ---- ------------------------
> > > > ----------------
> > > > Scanning global bootmeth 'efi_mgr':
> > > > ( gets stuck here)
> > > >
> > > > or
> > > >
> > > > => bootefi hello
> > > > (gets stuck)
> > > >
> > > > To debug I disabled CONFIG_EFI_MM_COMM_TEE to not get stuck and bypass
> > > > the error and go to Linux. My understanding is that
> > > > CONFIG_EFI_MM_COMM_TEE is only required to read/write efi variables at
> > > > u-boot level but OPTEE is running the StandaloneMM service. Am I
> > > > right?
> > >
> > > U-Boot has two ways of storing EFI variables [0] . You can either
> > > store them in a file or the RPMB partition. The correct thing to do,
> > > since you want to use the RPMB, is enable CONFIG_EFI_MM_COMM_TEE. I am
> > > not sure why the hand happens, but one thing we can improve is figure
> > > out why it hangs and print a useful message.
> > > There are a number of reasons that might lead to a failure. Is the
> > > RPMB key programmed on your board? Have a look at this [1] in case it
> > > helps
> > >
> > > >
> > > > > >
> > > > > > # tee-supplicant
> > > > > > D/TC:? 0 tee_ta_init_session_with_context:557 Re-open trusted service
> > > > > > 7011a688-ddde-4053-a5a9-7b3c4ddf13b8
> > > > > > D/TC:? 0 load_stmm:297 stmm load address 0x40004000
> > > > > > D/TC:? 0 spm_handle_scall:859 Received FFA version
> > > > > > D/TC:? 0 spm_handle_scall:867 Received FFA direct request
> > > > > > D/TC:? 0 spm_handle_scall:867 Received FFA direct request
> > > > > > D/TC:? 0 spm_handle_scall:867 Received FFA direct request
> > > > > > D/TC:? 0 spm_handle_scall:867 Received FFA direct request
> > > > > > D/TC:? 0 spm_handle_scall:867 Received FFA direct request
> > > > > > D/TC:? 0 spm_handle_scall:867 Received FFA direct request
> > > > > > D/TC:? 0 spm_handle_scall:867 Received FFA direct request
> > > > > > D/TC:? 0 spm_handle_scall:867 Received FFA direct request
> > > > > > D/TC:? 0 spm_handle_scall:867 Received FFA direct request
> > > > > > D/TC:? 0 spm_handle_scall:867 Received FFA direct request
> > > > > > D/TC:? 0 spm_handle_scall:867 Received FFA direct request
> > > > > > D/TC:? 0 spm_handle_scall:867 Received FFA direct request
> > > > > > D/TC:? 0 spm_handle_scall:867 Received FFA direct request
> > > > > > D/TC:? 0 spm_handle_scall:867 Received FFA direct request
> > > > > > D/TC:? 0 spm_handle_scall:867 Received FFA direct request
> > > > > > D/TC:? 0 spm_handle_scall:867 Received FFA direct request
> > >
> > > If I had to guess, OP-TEE doesn't store the variables in the RPMB, can
> > > you compile it with a bit more debugging enabled?
> > >
> >
> > Here is a log with CFG_TEE_CORE_LOG_LEVEL=4, CFG_TEE_CORE_DEBUG=y and
> > CFG_TEE_TA_LOG_LEVEL=4
> >
> > https://paste.centos.org/view/eed83a5b
> >
> > At the beginning of the log I see
> >
> > D/TC:0 0 check_ta_store:449 TA store: "REE"
> >
> > Which looks wrong to me as I built optee with:
> > CFG_REE_FS=n
> > CFG_RPMB_FS_DEV_ID=0
> > CFG_RPMB_FS=y
>
> Yes it does look wrong. Our compilation flags are
> CFG_RPMB_FS=y CFG_RPMB_FS_DEV_ID=0 CFG_RPMB_WRITE_KEY=y
> CFG_RPMB_TESTKEY=y CFG_REE_FS=n CFG_CORE_ARM64_PA_BITS=48
> CFG_SCTLR_ALIGNMENT_CHECK=n
>
Mine are very similar
make CROSS_COMPILE="$CC32" CROSS_COMPILE64="$CC64" \
PLATFORM=k3-j784s4 CFG_ARM64_core=y CFG_CONSOLE_UART=0x8 \
CFG_RPMB_FS_DEV_ID=0 CFG_REE_FS=n CFG_RPMB_FS=y \
CFG_RPMB_WRITE_KEY=y CFG_RPMB_TESTKEY=y \
CFG_STMM_PATH=BL32_AP_MM.fd \
CFG_CORE_HEAP_SIZE=524288 CFG_CORE_DYN_SHM=y CFG_SCTLR_ALIGNMENT_CHECK=n \
CFG_TEE_CORE_LOG_LEVEL=4 CFG_TEE_CORE_DEBUG=y CFG_TEE_TA_LOG_LEVEL=4
There is a difference with CFG_CORE_ARM64_PA_BITS=48 , my platform defines it to
core/arch/arm/plat-k3/conf.mk:$(call force,CFG_CORE_ARM64_PA_BITS,36)
But I don't think this is the problem.
> The testkey etc aren't required if your board has a way of reading the
> RPMB key from a secure location -- in fact, using the testkey is not
> secure. Is the RPMB programmed on your board? Also can you make sure
> CFG_RPMB_FS_DEV_ID needs to be 0? How many sd interfaces your board
> has?
My board has two interfaces, an eMMC and a SD-card, 0 is indeed the
eMMC and I'm using the testkey which I assume was programmed the first
time I booted with all this. Unfortunately I lost the traces. But,
optee_rpmb works. I.e:
=> optee_rpmb write test 1234
=> optee_rpmb read test 4
Read 4 bytes, value = 1234
> IOW in U-Boot does 'mmc dev 0 && mmc info' print information for the
> RPMB partition?
>
=> mmc dev 0
switch to partitions #0, OK
mmc0(part 0) is current device
=> mmc info
Device: mmc at 4f80000
Manufacturer ID: 13
OEM: 4e
Name: G1M15L
Bus Speed: 200000000
Mode: HS400 (200MHz)
Rd Block Len: 512
MMC version 5.1
High Capacity: Yes
Capacity: 29.6 GiB
Bus Width: 8-bit DDR
Erase Group Size: 512 KiB
HC WP Group Size: 8 MiB
User Capacity: 29.6 GiB WRREL
Boot Capacity: 31.5 MiB ENH
RPMB Capacity: 4 MiB ENH
Boot area 0 is not write protected
Boot area 1 is not write protected
=> mmc list
mmc at 4f80000: 0 (eMMC)
mmc at 4fb0000: 1
Any interaction with efi gives me the same result (printenv -e,
efidebug, bootefi ...)
=> efidebug query -bs -rt -nv
D/TC:? 0 load_stmm:297 stmm load address 0x40004000
D/TC:? 0 spm_handle_scall:859 Received FFA version
D/TC:? 0 spm_handle_scall:867 Received FFA direct request
D/TC:? 0 spm_handle_scall:867 Received FFA direct request
D/TC:? 0 spm_handle_scall:867 Received FFA direct request
D/TC:? 0 spm_handle_scall:867 Received FFA direct request
D/TC:? 0 spm_handle_scall:867 Received FFA direct request
D/TC:? 0 spm_handle_scall:867 Received FFA direct request
D/TC:? 0 spm_handle_scall:867 Received FFA direct request
D/TC:? 0 spm_handle_scall:867 Received FFA direct request
D/TC:? 0 spm_handle_scall:867 Received FFA direct request
D/TC:? 0 spm_handle_scall:867 Received FFA direct request
D/TC:? 0 spm_handle_scall:867 Received FFA direct request
D/TC:? 0 spm_handle_scall:867 Received FFA direct request
D/TC:? 0 spm_handle_scall:867 Received FFA direct request
D/TC:? 0 spm_handle_scall:867 Received FFA direct request
D/TC:? 0 spm_handle_scall:867 Received FFA direct request
D/TC:? 0 spm_handle_scall:867 Received FFA direct request
... stuck here ... I need to reset the board
Will continue to see if I can get more useful messages
Thanks,
Enric
> Thanks
> /Ilias
> >
> > I'll try to add some more prints to verify if REE is used as a store
> > system, I assume this should say something about RPMB. Am I right with
> > this?
>
>
> >
> > > > > >
> > > > > > And tracing the function calls gives me that:
> > > > > >
> > > > > > tee_stmm_efi_probe() {
> > > > > > tee_client_open_context() {
> > > > > > optee_get_version() {
> > > > > > tee_get_drvdata(); (ret=0xffff000002e55800)
> > > > > > } (ret=0xd)
> > > > > > tee_ctx_match(); (ret=0x1)
> > > > > > optee_smc_open() {
> > > > > > tee_get_drvdata(); (ret=0xffff000002e55800)
> > > > > > optee_open() {
> > > > > > tee_get_drvdata(); (ret=0xffff000002e55800)
> > > > > > } (ret=0x0)
> > > > > > } (ret=0x0)
> > > > > > } (ret=0xffff000004e71c80)
> > > > > > tee_client_open_session() {
> > > > > > optee_open_session() {
> > > > > > tee_get_drvdata(); (ret=0xffff000002e55800)
> > > > > > optee_get_msg_arg() {
> > > > > > tee_get_drvdata(); (ret=0xffff000002e55800)
> > > > > > tee_shm_get_va(); (ret=0xffff000002909000)
> > > > > > } (ret=0xffff000002909000)
> > > > > > tee_session_calc_client_uuid(); (ret=0x0)
> > > > > > optee_to_msg_param(); (ret=0x0)
> > > > > > optee_smc_do_call_with_arg() {
> > > > > > tee_get_drvdata(); (ret=0xffff000002e55800)
> > > > > > tee_shm_get_va(); (ret=0xffff000002909000)
> > > > > > tee_shm_get_va(); (ret=0xffff000002909060)
> > > > > > optee_cq_wait_init(); (ret=0xffff000002e55910)
> > > > > > optee_smccc_smc(); (ret=0xffff0004)
> > > > > > tee_get_drvdata(); (ret=0xffff000002e55800)
> > > > > > optee_smccc_smc(); (ret=0xffff0004)
> > > > > > tee_get_drvdata(); (ret=0xffff000002e55800)
> > > > > > optee_smccc_smc(); (ret=0xffff0004)
> > > > > > tee_get_drvdata(); (ret=0xffff000002e55800)
> > > > > > optee_smccc_smc(); (ret=0xffff0004)
> > > > > > tee_get_drvdata(); (ret=0xffff000002e55800)
> > > > > > optee_smccc_smc(); (ret=0xffff0004)
> > > > > > ... continues sending this forever ...
> > > > > > ... Hit ^C to stop recording ...
> > > > > > tee_get_drvdata(); (ret=0xffff000002e55800)
> > > > > > optee_smccc_smc() {
> > > > > >
> > > > > > [1] https://docs.u-boot.org/en/latest/develop/uefi/uefi.html#using-op-tee-for-efi-variables
> > > > > >
> > > > > > Thanks in advance,
> > > > >
> > > > > The most common problem with this is miscompiling the tee_supplicant
> > > > > application.
> > > > > Since we don't know if the system has an RPMB, we emulate it in the
> > > > > tee_supplicant. How did you get the supplicant and can you check if it
> > > > > was compiled with RPMB_EMU=0 or 1?
> > > > >
> > > >
> > > > I'm using the tee-supplicant provided by the fedora package which is
> > > > built with ` -DRPMB_EMU=0`, I think that's correct, right?
> > > >
> > >
> > > Yes, this is correct. We fixed the Fedora package to compile the
> > > supplicant correctly a while back.
> > >
> > > [0] https://www.linaro.org/blog/uefi-secureboot-in-u-boot/
> > > [1] https://apalos.github.io/Protected%20UEFI%20variables%20with%20U-Boot.html#Protected%20UEFI%20variables%20with%20U-Boot
> > >
> > >
> > > Regards
> > > /Ilias
> > > > Thanks,
> > > > Enric
> > > >
> > > > > Thanks
> > > > > /Ilias
> > > > >
> > > > > > Enric
> > > > > >
> > > > >
> > > >
> > >
> >
>
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