From ea8c66fe8d8f4f93df941e52120a3512d7bf5128 Mon Sep 17 00:00:00 2001 From: Yury Norov Date: Thu, 19 May 2022 10:15:04 -0700 Subject: KVM: x86: hyper-v: fix type of valid_bank_mask In kvm_hv_flush_tlb(), valid_bank_mask is declared as unsigned long, but is used as u64, which is wrong for i386, and has been spotted by LKP after applying "KVM: x86: hyper-v: replace bitmap_weight() with hweight64()" https://lore.kernel.org/lkml/20220510154750.212913-12-yury.norov@gmail.com/ But it's wrong even without that patch because now bitmap_weight() dereferences a word after valid_bank_mask on i386. >> include/asm-generic/bitops/const_hweight.h:21:76: warning: right shift count >= width of type +[-Wshift-count-overflow] 21 | #define __const_hweight64(w) (__const_hweight32(w) + __const_hweight32((w) >> 32)) | ^~ include/asm-generic/bitops/const_hweight.h:10:16: note: in definition of macro '__const_hweight8' 10 | ((!!((w) & (1ULL << 0))) + \ | ^ include/asm-generic/bitops/const_hweight.h:20:31: note: in expansion of macro '__const_hweight16' 20 | #define __const_hweight32(w) (__const_hweight16(w) + __const_hweight16((w) >> 16)) | ^~~~~~~~~~~~~~~~~ include/asm-generic/bitops/const_hweight.h:21:54: note: in expansion of macro '__const_hweight32' 21 | #define __const_hweight64(w) (__const_hweight32(w) + __const_hweight32((w) >> 32)) | ^~~~~~~~~~~~~~~~~ include/asm-generic/bitops/const_hweight.h:29:49: note: in expansion of macro '__const_hweight64' 29 | #define hweight64(w) (__builtin_constant_p(w) ? __const_hweight64(w) : __arch_hweight64(w)) | ^~~~~~~~~~~~~~~~~ arch/x86/kvm/hyperv.c:1983:36: note: in expansion of macro 'hweight64' 1983 | if (hc->var_cnt != hweight64(valid_bank_mask)) | ^~~~~~~~~ CC: Borislav Petkov CC: Dave Hansen CC: H. Peter Anvin CC: Ingo Molnar CC: Jim Mattson CC: Joerg Roedel CC: Paolo Bonzini CC: Sean Christopherson CC: Thomas Gleixner CC: Vitaly Kuznetsov CC: Wanpeng Li CC: kvm@vger.kernel.org CC: linux-kernel@vger.kernel.org CC: x86@kernel.org Reported-by: kernel test robot Signed-off-by: Yury Norov Message-Id: <20220519171504.1238724-1-yury.norov@gmail.com> Signed-off-by: Paolo Bonzini --- arch/x86/kvm/hyperv.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'arch') diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c index 46f9dfb60469..a0702b6be3e8 100644 --- a/arch/x86/kvm/hyperv.c +++ b/arch/x86/kvm/hyperv.c @@ -1914,7 +1914,7 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc) struct hv_send_ipi_ex send_ipi_ex; struct hv_send_ipi send_ipi; DECLARE_BITMAP(vcpu_mask, KVM_MAX_VCPUS); - unsigned long valid_bank_mask; + u64 valid_bank_mask; u64 sparse_banks[KVM_HV_MAX_SPARSE_VCPU_SET_BITS]; u32 vector; bool all_cpus; @@ -1956,7 +1956,7 @@ static u64 kvm_hv_send_ipi(struct kvm_vcpu *vcpu, struct kvm_hv_hcall *hc) valid_bank_mask = send_ipi_ex.vp_set.valid_bank_mask; all_cpus = send_ipi_ex.vp_set.format == HV_GENERIC_SET_ALL; - if (hc->var_cnt != bitmap_weight(&valid_bank_mask, 64)) + if (hc->var_cnt != bitmap_weight((unsigned long *)&valid_bank_mask, 64)) return HV_STATUS_INVALID_HYPERCALL_INPUT; if (all_cpus) -- cgit