On 3/5/26 2:05 AM, Florian Hofhammer wrote:
Hi,
This patch series builds on top of the discussion from the thread at
https://lore.kernel.org/qemu-devel/[email protected]/
and adds a plugin API function to set the program counter of the guest,
as just writing to it via qemu_plugin_write_register() has no direct
effect.
This version v7 of the patch series addresses the requested changes from
the previous v6 submission (details below).
Note: checkpatch.pl still reports a warning about line length violations
in patch nr. 7/8 but I did not fix this, as the line was already > 80
characters long previously, the change added only a single character,
and I think the readability of the code is better as it is now. Please
let me know if you disagree and would like me to fix this!
@Pierrick: you already reviewed patch 3/7 (now 4/8) previously, but I
had to change the regex in scripts/qemu-plugin-symbols.py to account for
attributes, so please re-review!
Best regards,
Florian
Changes:
v7:
- Add Pierrick's patch to clamp 32-bit registers to prevent accidental
sign extension
- Fix documentation build by using __attribute__((__noreturn__)) instead
of G_NORETURN (required adjusting scripts/qemu-plugin-symbols.py).
- Rework test-plugin-set-pc test to get rid of volatile guard and make
control flow more linear
- Link to v6:
https://lore.kernel.org/qemu-devel/[email protected]
v6:
- update commit message for patch 4/7
v5:
- make QEMU abort via asserts instead of just returning an error from
the plugin API if preconditions are violated
- extend tests for qemu_plugin_set_pc() to different contexts
- fix issues highlighted by checkpatch.pl
v4:
- switch strcmp out in favor of g_strcmp0
- split the patch introducing the qemu_plugin_set_pc() API into three
patches, two for preparing the plugin infrastructure and the syscall
handling code and a third introducing the actual plugin API
v3:
- make PC registers read-only across architectures
- add tests for read-only registers
- adjust test structure for qemu_plugin_set_pc() by moving
architecture-specific tests into corresponding directories
v2:
- add setjmp() in syscall handling path to allow PC redirection from
syscall callbacks (via longjmp(), the cpu_loop()'s setjmp() for
exiting a TB would not be live anymore in syscall handlers)
- add flags to ensure the qemu_plugin_set_pc() API is only called from
contexts where the CPU is live
- add test for qemu_plugin_set_pc() API
v1:
- initial version
---
Florian Hofhammer (7):
plugins: add flag to specify whether PC is rw
linux-user: make syscall emulation interruptible
plugins: add PC diversion API function
tests/tcg: add tests for qemu_plugin_set_pc API
plugins: add read-only property for registers
plugins: prohibit writing to read-only registers
tests/tcg/plugins: test register accesses
Pierrick Bouvier (1):
plugins/core: clamp syscall arguments if target is 32-bit
MAINTAINERS | 1 +
include/plugins/qemu-plugin.h | 19 +++
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 | 1 +
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 | 9 +-
linux-user/or1k/cpu_loop.c | 2 +-
linux-user/ppc/cpu_loop.c | 10 +-
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 | 16 +++
linux-user/xtensa/cpu_loop.c | 1 +
plugins/api.c | 42 ++++++-
plugins/core.c | 50 ++++++--
scripts/qemu-plugin-symbols.py | 9 +-
tests/tcg/arm/Makefile.target | 6 +
tests/tcg/hexagon/Makefile.target | 8 ++
tests/tcg/multiarch/Makefile.target | 17 ++-
.../multiarch/{ => plugin}/check-plugin-output.sh | 0
.../{ => plugin}/test-plugin-mem-access.c | 0
tests/tcg/multiarch/plugin/test-plugin-set-pc.c | 134 +++++++++++++++++++++
tests/tcg/plugins/meson.build | 2 +
tests/tcg/plugins/registers.c | 79 ++++++++++++
tests/tcg/plugins/setpc.c | 109 +++++++++++++++++
33 files changed, 514 insertions(+), 44 deletions(-)
---
base-commit: 3fb456e9a0e9eef6a71d9b49bfff596a0f0046e9
change-id: 20260303-setpc-v5-c1df30bad07f
This was merged into master (2d3f78269a14a389aefecba28decd16dd5151802).
Thank you for your contribution!
Regards,
Pierrick
