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clfdev commented on The hidden JTAG in a Qualcomm/Snapdragon device’s USB port   linaro.org/blog/hidden-jt... · Posted by u/denysvitali
tripdout · 2 months ago
It will be really interesting to see what production devices this is enabled on - It mentions the OnePlus 6 at least which has it fused out but is still accessible.

Edit: How are they reading the eFuses on a production OnePlus 6? Do they have a Qualcomm-signed EL3 EDL loader?

It seems to exist as qcom,msm-eud in the device tree of a (unfortunately production) SM4350 device I have along with an eud_enable_reg. Time to recompile the kernel with `/dev/mem`.

clfdev · 2 months ago
heya, author of the blog post here. the op6 happens to work but it's limited to debugging in el1, if you do manage to trap in el2 all the registers read 0

the reason this works at all on this production device is because oneplus screwed up and shipped a "debug profile" in production. this is a vendor signed elf (flashed to the dpdb partition or something like that) containing configuration to enable certain debugging features.

the one we already know about is crashdump mode, the op6 will crashdump when you trigger an XPU violation or some kinds of bus abort, then you can dump the entire RAM and you dont even need to authenticate (no firehose just run bkerlers edl.py)

this has come in handy for mainline development a few times heh

but it seems that this profile also enables EUD which is super nice, that said i didnt manage to get breakpoints working at all yet....

clfdev commented on NewPipe on Linux, Using Android_translation_layer   flathub.org/apps/net.newp... · Posted by u/FuturisticGoo
clfdev · 10 months ago
If you have a device running postmarketOS or Alpine Linux you can try this out yourself with other Android apps. Just "sudo apk add android-translation-layer" and then run

$ android-translation-layer some-app.apk

I tried a few (F-Droid, Spotify, Megalodon) but they all failed with various issues, looks like there's a lot of API surface still not covered. Hopefully a lot of it is fairly easy to add now that the foundational work has been done!

u/clfdev

KarmaCake day20February 12, 2022View Original