Mesa uses this to determine what the executable name is in a process for
application profiles. Without thunking, the guest glibc sets this
correctly, with thunking mesa would pick up `FEX` instead of the app.
With this fixed, it fixes Dead Island rendering when thunks are enabled.
Plenty of other games in Mesa's application profiles that it would fix
as well.
On 36-bit VA systems the stack was ending up /wherever/ when it should
be at the top of the VA space (usually).
Additionally VDSO was getting mapped anywhere on 64-bit, so push that to
the top of the VA space as well.
Also removes a check for old kernels not supporting MAP_FIXED_NOREPLACE.
UML disables ASLR using a personality. FEX in the ELFCodeLoader was
accidentally erasing personalities. This caused UML to do a bootloop
trying to repeat disable ASLR.
It now gets ASLR disabled, but fails shortly afterwards.
For #5206
Execstack enables `READ_IMPLIES_EXEC` and we were accidentally
decoupling our expected persona due to the reordering of initialization.
This was causing the smc-1-dynamic test to fail because it's testing
execstack and our VMA tracking wasn't returning read-write VMAs as
executable once these decoupled.
Easy fix.
This allows the context and parent thread objects to be created earlier,
allowing the VDSO and ELFCodeLoader mapping functions to have a thread
object for tracking memory mappings through the regular guest routines.
This means that we no longer need to do any form of deferred handling
for code caching as all the state is ready early in the initialization
process.
A little bit of care needed to be taken to ensure we still close the
ELFCodeLoader's FDs later and that VDSO unmapping happens before tearing
down the parent thread, but overall this is mostly just passing the
InternalThreadState object around as normal.
I couldn't find any functional regression from this change alongside
code caching, but it would be good for @neobrain to double check this.
Still creates a copy of FEXInterpreter from FEX for downstream projects
to have some time to get off the old name. Creating a symlink is kind of
a pain in cmake so just doing an install copy is easy.
Ryan Houdek