lkml.org 
[lkml]   [2021]   [Nov]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 5.15 01/26] KVM: x86: avoid warning with -Wbitwise-instead-of-logical
Date
From: Paolo Bonzini <pbonzini@redhat.com>

commit 3d5e7a28b1ea2d603dea478e58e37ce75b9597ab upstream.

This is a new warning in clang top-of-tree (will be clang 14):

In file included from arch/x86/kvm/mmu/mmu.c:27:
arch/x86/kvm/mmu/spte.h:318:9: error: use of bitwise '|' with boolean operands [-Werror,-Wbitwise-instead-of-logical]
return __is_bad_mt_xwr(rsvd_check, spte) |
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
||
arch/x86/kvm/mmu/spte.h:318:9: note: cast one or both operands to int to silence this warning

The code is fine, but change it anyway to shut up this clever clogs
of a compiler.

Reported-by: torvic9@mailbox.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
arch/x86/kvm/mmu/spte.h | 7 +------
1 file changed, 1 insertion(+), 6 deletions(-)

--- a/arch/x86/kvm/mmu/spte.h
+++ b/arch/x86/kvm/mmu/spte.h
@@ -310,12 +310,7 @@ static inline bool __is_bad_mt_xwr(struc
static __always_inline bool is_rsvd_spte(struct rsvd_bits_validate *rsvd_check,
u64 spte, int level)
{
- /*
- * Use a bitwise-OR instead of a logical-OR to aggregate the reserved
- * bits and EPT's invalid memtype/XWR checks to avoid an extra Jcc
- * (this is extremely unlikely to be short-circuited as true).
- */
- return __is_bad_mt_xwr(rsvd_check, spte) |
+ return __is_bad_mt_xwr(rsvd_check, spte) ||
__is_rsvd_bits_set(rsvd_check, spte, level);
}


\
 
 \ /
  Last update: 2021-11-10 19:57    [W:0.177 / U:0.224 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site