linux-kernel - [PATCH v4 0/4] Upgrade READ_ONCE() to RCpc acquire on arm64 with LTO

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: <20201103121721.5166-1-will@kernel.org>
Date:   Tue,  3 Nov 2020 12:17:17 +0000
From:   Will Deacon <will@...nel.org>
To:     linux-arm-kernel@...ts.infradead.org
Cc:     Will Deacon <will@...nel.org>, Kees Cook <keescook@...omium.org>,
        Catalin Marinas <catalin.marinas@....com>,
        Sami Tolvanen <samitolvanen@...gle.com>,
        Masahiro Yamada <masahiroy@...nel.org>,
        Peter Zijlstra <peterz@...radead.org>,
        linux-kernel@...r.kernel.org
Subject: [PATCH v4 0/4] Upgrade READ_ONCE() to RCpc acquire on arm64 with LTO

Hi all,

These patches were previously posted as part of a larger series enabling
architectures to override __READ_ONCE():

  v3: https://lore.kernel.org/lkml/20200710165203.31284-1-will@kernel.org/

With the bulk of that merged, the four patches here override READ_ONCE()
so that it gains RCpc acquire semantics on arm64 when LTO is enabled. We
can revisit this as and when the compiler provides a means for us to reason
about the result of dependency-breaking optimisations. In the meantime,
this unblocks LTO for arm64, which I would really like to see merged so
that we can focus on enabling CFI.

I plan to queue these on their own branch in the arm64 tree for 5.11 at
-rc3.

Cheers,

Will

Cc: Kees Cook <keescook@...omium.org>
Cc: Catalin Marinas <catalin.marinas@....com>
Cc: Sami Tolvanen <samitolvanen@...gle.com>
Cc: Masahiro Yamada <masahiroy@...nel.org>
Cc: Peter Zijlstra <peterz@...radead.org>
Cc: linux-kernel@...r.kernel.org

--->8

Will Deacon (4):
  arm64: alternatives: Split up alternative.h
  arm64: cpufeatures: Add capability for LDAPR instruction
  arm64: alternatives: Remove READ_ONCE() usage during patch operation
  arm64: lto: Strengthen READ_ONCE() to acquire when CONFIG_LTO=y

 arch/arm64/Kconfig                          |   3 +
 arch/arm64/include/asm/alternative-macros.h | 276 ++++++++++++++++++++
 arch/arm64/include/asm/alternative.h        | 267 +------------------
 arch/arm64/include/asm/cpucaps.h            |   3 +-
 arch/arm64/include/asm/insn.h               |   3 +-
 arch/arm64/include/asm/rwonce.h             |  63 +++++
 arch/arm64/kernel/alternative.c             |   7 +-
 arch/arm64/kernel/cpufeature.c              |  10 +
 arch/arm64/kernel/vdso/Makefile             |   2 +-
 arch/arm64/kernel/vdso32/Makefile           |   2 +-
 arch/arm64/kernel/vmlinux.lds.S             |   2 +-
 11 files changed, 364 insertions(+), 274 deletions(-)
 create mode 100644 arch/arm64/include/asm/alternative-macros.h
 create mode 100644 arch/arm64/include/asm/rwonce.h

-- 
2.29.1.341.ge80a0c044ae-goog