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 <bp@alien8.de>
CC: Dave Hansen <dave.hansen@linux.intel.com>
CC: H. Peter Anvin <hpa@zytor.com>
CC: Ingo Molnar <mingo@redhat.com>
CC: Jim Mattson <jmattson@google.com>
CC: Joerg Roedel <joro@8bytes.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Sean Christopherson <seanjc@google.com>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Vitaly Kuznetsov <vkuznets@redhat.com>
CC: Wanpeng Li <wanpengli@tencent.com>
CC: kvm@vger.kernel.org
CC: linux-kernel@vger.kernel.org
CC: x86@kernel.org
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Message-Id: <20220519171504.1238724-1-yury.norov@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
1 file changed
