On Mon, Jul 10, 2023, Vitaly Kuznetsov wrote: > kernel test robot <lkp@xxxxxxxxx> writes: > > > Hi Vitaly, > > > > First bad commit (maybe != root cause): > > > > tree: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git linux-5.15.y > > head: d54cfc420586425d418a53871290cc4a59d33501 > > commit: cb188e07105f2216f5efbefac95df4b6ce266906 [55/9999] KVM: x86: hyper-v: HVCALL_SEND_IPI_EX is an XMM fast hypercall > > config: i386-buildonly-randconfig-r006-20230708 (https://download.01.org/0day-ci/archive/20230708/202307080326.zDp7E3o0-lkp@xxxxxxxxx/config) > > compiler: clang version 15.0.7 (https://github.com/llvm/llvm-project.git 8dfdcc7b7bf66834a761bd8de445840ef68e4d1a) > > reproduce: (https://download.01.org/0day-ci/archive/20230708/202307080326.zDp7E3o0-lkp@xxxxxxxxx/reproduce) > > > > If you fix the issue in a separate patch/commit (i.e. not just a new version of > > the same patch/commit), kindly add following tags > > | Reported-by: kernel test robot <lkp@xxxxxxxxx> > > | Closes: https://lore.kernel.org/oe-kbuild-all/202307080326.zDp7E3o0-lkp@xxxxxxxxx/ > > > > All errors (new ones prefixed by >>): > > > >>> arch/x86/kvm/hyperv.c:2185:5: error: stack frame size (1036) exceeds limit (1024) in 'kvm_hv_hypercall' [-Werror,-Wframe-larger-than] > > int kvm_hv_hypercall(struct kvm_vcpu *vcpu) > > ^ > > 1 error generated. > > (sorry for delayed reply) > > This used to be a warning (without CONFIG_KVM_WERROR I guess?) :-) E.g. > > https://lore.kernel.org/kvm/87zgg6sza8.fsf@xxxxxxxxxx/#t > > where Nathan explained LLVM's behavior: > > https://lore.kernel.org/kvm/Yvp87jlVWg0e376v@dev-arch.thelio-3990X/ > > This was 'fixed' upstream with > > commit 7d5e88d301f84a7b64602dbe3640f288223095ea > Author: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx> > Date: Tue Nov 1 15:53:56 2022 +0100 > > KVM: x86: hyper-v: Use preallocated buffer in 'struct kvm_vcpu_hv' instead of on-stack 'sparse_banks' > > and personally, I'm not against backporting it to 5.15.y but I seriously > doubt it is worth the hassle (i386 KVM + llvm + CONFIG_KVM_WERROR is > likely an impossible combo). > > Also, there seems to be another build problem with CONFIG_KVM_WERROR I > met with clan-16 and the same config: > > ../arch/x86/kvm/x86.c:2315:19: error: unused function 'gtod_is_based_on_tsc' [-Werror,-Wunused-function] > static inline int gtod_is_based_on_tsc(int mode) > > TL;DR: Let's ignore this for 5.15, not worth fixing IMO. Cc: kvm@ to > check if anyone thinks differently. Ya, ignore it. KVM_WERROR is off-by-default for 32-bit builds, and all evidence suggests that no one uses KVM with 32-bit kernels these days, so I can't imagine this negatively affects anyone. 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
