On Tue, Nov 21, 2023 at 11:02 PM Ilya Leoshkevich <iii@xxxxxxxxxxxxx> wrote: > > It should be possible to have inline functions in the s390 header > files, which call kmsan_unpoison_memory(). The problem is that these > header files might be included by the decompressor, which does not > contain KMSAN runtime, causing linker errors. > > Not compiling these calls if __SANITIZE_MEMORY__ is not defined - > either by changing kmsan-checks.h or at the call sites - may cause > unintended side effects, since calling these functions from an > uninstrumented code that is linked into the kernel is valid use case. > > One might want to explicitly distinguish between the kernel and the > decompressor. Checking for a decompressor-specific #define is quite > heavy-handed, and will have to be done at all call sites. > > A more generic approach is to provide a dummy kmsan_unpoison_memory() > definition. This produces some runtime overhead, but only when building > with CONFIG_KMSAN. The benefit is that it does not disturb the existing > KMSAN build logic and call sites don't need to be changed. > > Signed-off-by: Ilya Leoshkevich <iii@xxxxxxxxxxxxx> Reviewed-by: Alexander Potapenko <glider@xxxxxxxxxx>
