From c5ffd16ba4c8fd3601742cc9d2b3cff03995dd5d Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Tue, 20 Jun 2023 18:57:12 +0100 Subject: 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 Message-Id: <20230620175712.1331625-1-peter.maydell@linaro.org> Signed-off-by: Richard Henderson --- include/hw/core/cpu.h | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) (limited to 'include/hw') 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; -- cgit v1.1