Changes since v3:
1) Reworded the first commit comment to note that the need to clear
cache is implementation-dependent.
2) CTR_EL0.DIC is now cleared in user mode to indicate that IC IVAU
must be used.
3) The test case now only uses DC CVAU / IC IVAU when this is
required, as indicated by CTR_EL0.{DIC,IDC}. There have been no
changes outside of the function `mark_code_modified`
----
When running in user-mode QEMU currently fails to emulate JITs that
use dual-mapped code to get around W^X restrictions, where one mapping
is writable and one is executable. As it has no way of knowing that a
write to the writable region is reflected in the executable one, it
fails to invalidate previously translated code which leads to a crash
at best.
(Note that system mode is unaffected as the softmmu is fully aware of
what is going on.)
This patch series catches changes to dual-mapped code by honoring the
cache management instructions required to make things work on actual
hardware.
See https://gitlab.com/qemu-project/qemu/-/issues/1034 for more
background information
John Högberg (2):
target/arm: Handle IC IVAU to improve compatibility with JITs
tests/tcg/aarch64: Add testcases for IC IVAU and dual-mapped code
target/arm/cpu.c | 13 ++
target/arm/helper.c | 47 +++++++-
tests/tcg/aarch64/Makefile.target | 3 +-
tests/tcg/aarch64/icivau.c | 189 ++++++++++++++++++++++++++++++
4 files changed, 248 insertions(+), 4 deletions(-)
create mode 100644 tests/tcg/aarch64/icivau.c
--
2.38.5
