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author | Peter Maydell <peter.maydell@linaro.org> | 2023-06-20 18:57:12 +0100 |
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committer | Richard Henderson <richard.henderson@linaro.org> | 2023-06-21 07:19:46 +0200 |
commit | c5ffd16ba4c8fd3601742cc9d2b3cff03995dd5d (patch) | |
tree | 37fda109b162c34f6147a299dcfae638a9db3414 /include/hw | |
parent | 2346098b9586f93fa596435b07fce1541151e2bd (diff) | |
download | qemu-c5ffd16ba4c8fd3601742cc9d2b3cff03995dd5d.zip qemu-c5ffd16ba4c8fd3601742cc9d2b3cff03995dd5d.tar.gz qemu-c5ffd16ba4c8fd3601742cc9d2b3cff03995dd5d.tar.bz2 |
Revert "cputlb: Restrict SavedIOTLB to system emulation"
This reverts commit d7ee93e24359703debf4137f4cc632563aa4e8d1.
That commit tries to make a field in the CPUState struct not be
present when CONFIG_USER_ONLY is set. Unfortunately, you can't
conditionally omit fields in structs like this based on ifdefs that
are set per-target. If you try it, then code in files compiled
per-target (where CONFIG_USER_ONLY is or can be set) will disagree
about the struct layout with files that are compiled once-only (where
this kind of ifdef is never set).
This manifests specifically in 'make check-tcg' failing, because code
in cpus-common.c that sets up the CPUState::cpu_index field puts it
at a different offset from the code in plugins/core.c in
qemu_plugin_vcpu_init_hook() which reads the cpu_index field. The
latter then hits an assert because from its point of view every
thread has a 0 cpu_index. There might be other weird behaviour too.
Mostly we catch this kind of bug because the CONFIG_whatever is
listed in include/exec/poison.h and so the reference to it in
build-once source files will then cause a compiler error.
Unfortunately CONFIG_USER_ONLY is an exception to that: we have some
places where we use it in "safe" ways in headers that will be seen by
once-only source files (e.g. ifdeffing out function prototypes) and
it would be a lot of refactoring to be able to get to a position
where we could poison it. This leaves us in a "you have to be
careful to walk around the bear trap" situation...
Fixes: d7ee93e243597 ("cputlb: Restrict SavedIOTLB to system emulation")
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20230620175712.1331625-1-peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Diffstat (limited to 'include/hw')
-rw-r--r-- | include/hw/core/cpu.h | 6 |
1 files changed, 2 insertions, 4 deletions
diff --git a/include/hw/core/cpu.h b/include/hw/core/cpu.h index ee8d6b4..4871ad8 100644 --- a/include/hw/core/cpu.h +++ b/include/hw/core/cpu.h @@ -226,7 +226,7 @@ struct CPUWatchpoint { QTAILQ_ENTRY(CPUWatchpoint) entry; }; -#if defined(CONFIG_PLUGIN) && !defined(CONFIG_USER_ONLY) +#ifdef CONFIG_PLUGIN /* * For plugins we sometime need to save the resolved iotlb data before * the memory regions get moved around by io_writex. @@ -410,11 +410,9 @@ struct CPUState { #ifdef CONFIG_PLUGIN GArray *plugin_mem_cbs; -#if !defined(CONFIG_USER_ONLY) /* saved iotlb data from io_writex */ SavedIOTLB saved_iotlb; -#endif /* !CONFIG_USER_ONLY */ -#endif /* CONFIG_PLUGIN */ +#endif /* TODO Move common fields from CPUArchState here. */ int cpu_index; |