Hi, As originally discussed in the thread at https://lists.nongnu.org/archive/html/qemu-devel/2025-08/msg00656.html and later proposed in a patch at https://lists.nongnu.org/archive/html/qemu-devel/2025-09/msg02218.html, I am sending an updated version of my patch based on the previous feedback.
Notable changes to v1: - Added a setjmp() in the syscall handling path to allow redirecting the PC via cpu_loop_exit() also in syscall callbacks. The previous version would only work in instruction execution / memory access callback contexts, as the setjmp() corresponding to the longjmp() in cpu_loop_exit() was only live in those contexts. - Added a flag to make sure the new API function is only called in contexts where it makes sense, i.e., during execution of guest code. - Added a test that checks the new functionality by skipping a non-existent sentinel syscall. I made it an RFC patch this time as I am not entirely sure if my setting/handling of the new flag makes sense the way it is. I briefly looked into making the QEMU_PLUGIN_CB_* flags actual flags via a bitfield instead of enum values, but that would have required touching a lot of code all over the place, so I'm not sure this is the way to go. Happy to get feedback and your thoughts on the patches! Thanks, Florian Florian Hofhammer (2): plugins: Add PC diversion API function tests/tcg: add test for qemu_plugin_set_pc API include/qemu/qemu-plugin.h | 15 +++++++ linux-user/aarch64/cpu_loop.c | 2 +- linux-user/alpha/cpu_loop.c | 2 +- linux-user/arm/cpu_loop.c | 2 +- linux-user/hexagon/cpu_loop.c | 2 +- linux-user/hppa/cpu_loop.c | 4 ++ linux-user/i386/cpu_loop.c | 8 ++-- linux-user/include/special-errno.h | 8 ++++ linux-user/loongarch64/cpu_loop.c | 5 ++- linux-user/m68k/cpu_loop.c | 2 +- linux-user/microblaze/cpu_loop.c | 2 +- linux-user/mips/cpu_loop.c | 5 ++- linux-user/openrisc/cpu_loop.c | 2 +- linux-user/ppc/cpu_loop.c | 6 ++- linux-user/riscv/cpu_loop.c | 2 +- linux-user/s390x/cpu_loop.c | 2 +- linux-user/sh4/cpu_loop.c | 2 +- linux-user/sparc/cpu_loop.c | 4 +- linux-user/syscall.c | 8 ++++ linux-user/xtensa/cpu_loop.c | 3 ++ plugins/api.c | 17 +++++++- plugins/core.c | 25 ++++++----- tests/tcg/multiarch/Makefile.target | 42 +++++++++++++++++++ .../tcg/multiarch/test-plugin-skip-syscalls.c | 26 ++++++++++++ tests/tcg/plugins/syscall.c | 6 +++ 25 files changed, 170 insertions(+), 32 deletions(-) create mode 100644 tests/tcg/multiarch/test-plugin-skip-syscalls.c -- 2.51.0
