unicorn/qemu/accel
Emilio G. Cota fc30b3d5cf
translate-all: exit from tb_phys_invalidate if qht_remove fails
Two or more threads might race while invalidating the same TB. We currently
do not check for this at all despite taking tb_lock, which means we would
wrongly invalidate the same TB more than once. This bug has actually been
hit by users: I recently saw a report on IRC, although I have yet to see
the corresponding test case.

Fix this by using qht_remove as the synchronization point; if it fails,
that means the TB has already been invalidated, and therefore there
is nothing left to do in tb_phys_invalidate.

Note that this solution works now that we still have tb_lock, and will
continue working once we remove tb_lock.

Backports commit cc689485ee3e9dca05765326ee8fd619a6ec48f0 from qemu
2018-03-15 15:51:58 -04:00
..
tcg translate-all: exit from tb_phys_invalidate if qht_remove fails 2018-03-15 15:51:58 -04:00
Makefile.objs tcg: Add generic translation framework 2018-03-04 14:31:16 -05:00