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Peter Anvin" , Peter Zijlstra , Thomas Gleixner , Borislav Petkov , Josh Poimboeuf , Andrey Ryabinin , Alexander Potapenko , Dmitry Vyukov , kasan-dev@googlegroups.com Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Wed, Apr 10, 2024 at 1:11=E2=80=AFPM Andrey Konovalov wrote: > > On Mon, Oct 9, 2023 at 4:35=E2=80=AFPM Uros Bizjak wr= ote: > > > > On Mon, Oct 9, 2023 at 1:41=E2=80=AFPM Ingo Molnar w= rote: > > > > > > > > > * Uros Bizjak wrote: > > > > > > > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig > > > > index ecb256954351..1edf4a5b93ca 100644 > > > > --- a/arch/x86/Kconfig > > > > +++ b/arch/x86/Kconfig > > > > @@ -2393,7 +2393,7 @@ config CC_HAS_NAMED_AS > > > > > > > > config USE_X86_SEG_SUPPORT > > > > def_bool y > > > > - depends on CC_HAS_NAMED_AS && SMP > > > > + depends on CC_HAS_NAMED_AS && SMP && !KASAN > > > > + depends on CC_HAS_NAMED_AS && SMP && !KASAN > > > > > > So I'd rather express this as a Kconfig quirk line, and explain each = quirk. > > > > > > Something like: > > > > > > depends on CC_HAS_NAMED_AS > > > depends on SMP > > > # > > > # -fsanitize=3Dkernel-address (KASAN) is at the moment incomp= atible > > > # with named address spaces - see GCC bug #12345. > > > # > > > depends on !KASAN > > > > This is now PR sanitizer/111736 [1], but perhaps KASAN people [CC'd] > > also want to be notified about this problem. > > > > [1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D111736 > > Filed a KASAN bug to track this: > https://bugzilla.kernel.org/show_bug.cgi?id=3D218703 Please note the fix in -tip tree that reenables sanitizers for fixed compil= ers: https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/commit/?h=3Dx86= /percpu&id=3D9ebe5500d4b25ee4cde04eec59a6764361a60709 Thanks, Uros.