On 9/16/25 17:27, Jan Beulich wrote: > On 16.09.2025 14:45, Dmytro Prokopchuk1 wrote: >> --- a/docs/misra/deviations.rst >> +++ b/docs/misra/deviations.rst >> @@ -98,6 +98,23 @@ Deviations related to MISRA C:2012 Rules: >> even when debug-only assertions like `ASSERT_UNREACHABLE()` are >> removed. >> - ECLAIR has been configured to ignore those statements. >> >> + * - R2.1 >> + - In the specific build configuration (when the config CONFIG_ACPI is >> not >> + defined) the 'BUG()' macro is intentionally used in the >> 'prepare_acpi()' >> + function in the header file 'xen/arch/arm/include/asm/domain_build.h' >> + defined as 'static inline' to trigger a runtime error if ACPI-related >> + features are used incorrectly. >> + - Tagged as `deliberate` for ECLAIR. > > I response to me outlining a deviation-less alternative you tried it out > and said it works. Then why is the deviation still being put in place?
Yes, that's true. I started with that prepare_acpi() function and I tried to move it into xen/include/xen/acpi.h header file under appropriate #ifdef: https://gitlab.com/xen-project/people/dimaprkp4k/xen/-/commit/d15cf91de92f1f8ec67911c51a13e7f095c1bcdd The Eclair didn't report violations related to the prepare_acpi(). I was confused why Eclair continued to report other violations, and didn't report for the prepare_acpi(). After a while I realized that this header file 'xen/include/xen/acpi.h' was placed into exclude list 'docs/misra/exclude-list.json', where: { "rel_path": "include/xen/acpi.h", "comment": "Imported from Linux, ignore for now" }, So, all violations from the 'include/xen/acpi.h' file were ignored. It was just a coincidence. > >> + * - R2.1 >> + - In the specific build configuration (when the config CONFIG_HAS_ITS >> is not >> + defined) the 'BUG()' macro is intentionally used in the >> 'gicv3_do_LPI()' >> + and 'gicv3_its_setup_collection()' functions defined as 'static >> inline' >> + in the header file 'xen/arch/arm/include/asm/gic_v3_its.h' to catch >> and >> + prevent any unintended execution of code that should only run when >> ITS is >> + available. >> + - Tagged as `deliberate` for ECLAIR. > > Taking both together and considering that really, when we no longer limit > Misra checking to specific configurations, we are going to have many more > of such "problems", I fear this way of deviating them simply doesn't scale. > Imo this needs a SAF-style deviation that can be applied without needing to > add a new section of text every time. > > Jan I agree. Actually, I saw similar functions. It could be tricky to maintain Eclair configs. I will create SAF-based patch. Thanks, Dmytro.
