Secure-Launch hangs in "Launch" call on Lenovo x13s

[TravMurav]

At least on firmware versions 1.58; 1.59 trying to run sltest.efi on x13s reliably hangs in hyp after making the "Launch" smc call.

Hyp is known to crash in the error handling path since it tries to flush the cache on already unmapped memory (I guess no one tested this :/ ). At least this is an educated guess since this is what happens on sc7180 too.

It's not possible to determine the exact error code that hyp attempted to return due to this and the hyp log buffer is not mapped to EL1 on sc8280xp. Hyp saves the address and size of the log ring buffer in imem at 0x146bfb30:

Shell> dmem -b 1464fb30 8
  146bfb30:  00 f0 1b 80  00 20 00 00

However reading the ring buffer at 0x801bf000 is not possible as touching that memory causes a synchronous exception.

The hyp code dumped from x13s seems to have no obvious differences from volterra on which sltest.efi is known to work.

Unfortunately there is no more sources of information to debug this issue only having a retail device. It's possible that reproducing the same issue on a device with hyp logs available might aid in debugging though.

[TravMurav]

The issue seems to be that x13s firmware doesn't accept smccc32 psci calls. (All other devices tested so far do). This probably means we had el2 all this time just couldn't assert it :/