linux-kernel - [PATCH 0/3] KVM: x86/mmu: Add macro for hugepage GFN mask

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20201027214300.1342-1-sean.j.christopherson@intel.com>
Date:   Tue, 27 Oct 2020 14:42:57 -0700
From:   Sean Christopherson <sean.j.christopherson@...el.com>
To:     Paolo Bonzini <pbonzini@...hat.com>
Cc:     Sean Christopherson <sean.j.christopherson@...el.com>,
        Vitaly Kuznetsov <vkuznets@...hat.com>,
        Wanpeng Li <wanpengli@...cent.com>,
        Jim Mattson <jmattson@...gle.com>,
        Joerg Roedel <joro@...tes.org>, kvm@...r.kernel.org,
        linux-kernel@...r.kernel.org, Ben Gardon <bgardon@...gle.com>
Subject: [PATCH 0/3] KVM: x86/mmu: Add macro for hugepage GFN mask

Add a macro, which is probably long overdue, to replace open coded
variants of "~(KVM_PAGES_PER_HPAGE(level) - 1)".  The straw that broke the
camel's back is the TDP MMU's round_gfn_for_level(), which goes straight
for the optimized approach of using NEG instead of SUB+NOT (gcc uses NEG
for both).  The use of '-(...)' made me do a double take (more like a
quadrupal take) when reading the TDP MMU code as my eyes/brain have been
heavily trained to look for the more common '~(... - 1)'.

Sean Christopherson (3):
  KVM: x86/mmu: Add helper macro for computing hugepage GFN mask
  KVM: x86/mmu: Open code GFN "rounding" in TDP MMU
  KVM: x86/mmu: Use hugepage GFN mask to compute GFN offset mask

 arch/x86/include/asm/kvm_host.h |  1 +
 arch/x86/kvm/mmu/mmu.c          |  4 ++--
 arch/x86/kvm/mmu/mmutrace.h     |  2 +-
 arch/x86/kvm/mmu/paging_tmpl.h  |  4 ++--
 arch/x86/kvm/mmu/tdp_iter.c     | 11 +++--------
 arch/x86/kvm/mmu/tdp_mmu.c      |  2 +-
 arch/x86/kvm/x86.c              |  6 +++---
 7 files changed, 13 insertions(+), 17 deletions(-)

-- 
2.28.0