Don't enable KVM_WERROR by default for x86-64 builds as KVM's one-off -Werror enabling is *mostly* superseded by the kernel-wide WERROR, and enabling KVM_WERROR by default can cause problems for developers working on other subsystems. E.g. subsystems that have a "zero W=1 regressions" rule can inadvertently build KVM with -Werror and W=1, and end up with build failures that are completely uninteresting to the developer (W=1 is prone to false positives, especially on older compilers). Keep KVM_WERROR as there are combinations where enabling WERROR isn't feasible, e.g. the default FRAME_WARN=1024 on i386 builds generates a non-zero number of warnings and thus errors, and there are far too many warnings throughout the kernel to enable WERROR with W=1 (building KVM with -Werror is desirable (with a sane compiler) as W=1 does generate useful warnings). Opportunistically drop the dependency on !COMPILE_TEST as it's completely meaningless (it was copied from i195's -Werror Kconfig), as the kernel's WERROR is explicitly *enabled* for COMPILE_TEST=y kernel's, i.e. enabling -Werror is obviosly not dependent on COMPILE_TEST=n. Reported-by: Jakub Kicinski <kuba@xxxxxxxxxx> Link: https://lore.kernel.org/all/20231006205415.3501535-1-kuba@xxxxxxxxxx Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx> --- arch/x86/kvm/Kconfig | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig index 950c12868d30..6cc0ea9cd91d 100644 --- a/arch/x86/kvm/Kconfig +++ b/arch/x86/kvm/Kconfig @@ -65,13 +65,13 @@ config KVM config KVM_WERROR bool "Compile KVM with -Werror" - # KASAN may cause the build to fail due to larger frames - default y if X86_64 && !KASAN - # We use the dependency on !COMPILE_TEST to not be enabled - # blindly in allmodconfig or allyesconfig configurations - depends on KVM - depends on (X86_64 && !KASAN) || !COMPILE_TEST - depends on EXPERT + # Disallow KVM's -Werror if KASAN is enabled, e.g. to guard against + # randomized configs from selecting KVM_WERROR=y, which doesn't play + # nice with KASAN. KASAN builds generates warnings for the default + # FRAME_WARN, i.e. KVM_WERROR=y with KASAN=y requires special tuning. + # Building KVM with -Werror and KASAN is still doable via enabling + # the kernel-wide WERROR=y. + depends on KVM && EXPERT && !KASAN help Add -Werror to the build flags for KVM. base-commit: 437bba5ad2bba00c2056c896753a32edf80860cc -- 2.42.0.655.g421f12c284-goog
