linux-kernel - Re: [RFC PATCH 0/5] livepatch: add support on arm64

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

Message-ID: <5568FDD2.2040005@hitachi.com>
Date:	Sat, 30 May 2015 09:01:22 +0900
From:	Masami Hiramatsu <masami.hiramatsu.pt@...achi.com>
To:	Li Bin <huawei.libin@...wei.com>, rostedt@...dmis.org,
	mingo@...nel.org, jpoimboe@...hat.com, sjenning@...hat.com,
	jkosina@...e.cz, vojtech@...e.cz, catalin.marinas@....com,
	will.deacon@....com
CC:	live-patching@...r.kernel.org,
	linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
	lizefan@...wei.com, felix.yang@...wei.com, guohanjun@...wei.com,
	xiexiuqi@...wei.com, takahiro.akashi@...aro.org,
	David Long <dave.long@...aro.org>
Subject: Re: [RFC PATCH 0/5] livepatch: add support on arm64

On 2015/05/28 14:51, Li Bin wrote:
> This patchset propose a method for gcc -mfentry feature(profile
> before prologue) implementation for arm64, and propose the livepatch
> implementation for arm64 based on this feature.
> The gcc implementation about this feature will be post to the gcc 
> community soon.
> 
> With this -mfentry feature, the entry of each function like:
> 
> foo:
>     mov x9, x30 
>     bl __fentry__
>     mov x30, x9
>     [prologue]
>     ... 
> 
> The x9 is a callee corruptible register, and the __fentry__ function
> is responsible to protect all registers, so it can be used to protect
> the x30. And the added two instructions which is register mov operation
> have ralatively small impact on performance.

Hm, this implementation looks good to me :)
This also enables us to KPROBES_ON_FTRACE too.

Thanks,

> 
> This patchset has been tested on arm64 platform.
> 
> Li Bin (4):
>   livepatch: ftrace: arm64: Add support for DYNAMIC_FTRACE_WITH_REGS
>   livepatch: ftrace: add ftrace_function_stub_ip function
>   livepatch: ftrace: arm64: Add support for -mfentry on arm64
>   livepatch: arm64: add support for livepatch on arm64
> 
> Xie XiuQi (1):
>   livepatch: arm64: support relocation in a module
> 
>  arch/arm64/Kconfig                 |    5 +
>  arch/arm64/include/asm/ftrace.h    |    9 +
>  arch/arm64/include/asm/livepatch.h |   45 +++++
>  arch/arm64/kernel/Makefile         |    1 +
>  arch/arm64/kernel/arm64ksyms.c     |    4 +
>  arch/arm64/kernel/entry-ftrace.S   |  154 +++++++++++++++-
>  arch/arm64/kernel/ftrace.c         |   28 +++-
>  arch/arm64/kernel/livepatch.c      |   41 ++++
>  arch/arm64/kernel/module.c         |  355 ++++++++++++++++++------------------
>  include/linux/ftrace.h             |    1 +
>  kernel/livepatch/core.c            |   17 ++-
>  kernel/trace/ftrace.c              |   32 ++++
>  scripts/recordmcount.pl            |    2 +-
>  13 files changed, 508 insertions(+), 186 deletions(-)
>  create mode 100644 arch/arm64/include/asm/livepatch.h
>  create mode 100644 arch/arm64/kernel/livepatch.c
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@...r.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
> 


-- 
Masami HIRAMATSU
Linux Technology Research Center, System Productivity Research Dept.
Center for Technology Innovation - Systems Engineering
Hitachi, Ltd., Research & Development Group
E-mail: masami.hiramatsu.pt@...achi.com
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/