Re: [PATCH] reduce the time of finding symbols for module

[Ruslan Bilovol]

Hi Li,

On Wed, Mar 29, 2017 at 4:50 AM, Li Bin <huawei.libin@xxxxxxxxxx> wrote:
> Hi,
[snip]
>
> Yeah, from 2014, we started to work on livepatch support on aarch64, and
> in May 2015, we pushed the solution to the livepatch community[1] and gcc
> community (mfentry feature on aarch64)[2]. And then, there were an another
> gcc solution from linaro [3], which proposes to implement a new option
> -fprolog-pad=N that generate a pad of N nops at the beginning of each
> function, and AFAIK, Torsten Duwe from SUSE is still discussing this method
> with gcc community.
>
> At this stage, we are validating the livepatch support on aarch64 based on
> aarch64 mfentry feature. When the community has a clear plan, we are happy
> to make adaptation and contribute our related work to the community, including
> the kpatch-build support :-)
>
> [1] livepatch: add support on arm64
> https://lkml.org/lkml/2015/5/28/54
> [2] [AArch64] support -mfentry feature for arm64
> https://gcc.gnu.org/ml/gcc-patches/2016-03/msg00756.html
> [3] Kernel livepatching support in GCC
> https://gcc.gnu.org/ml/gcc/2015-05/msg00267.html
> [4] arm64: ftrace with regs for livepatch support
> http://lists.infradead.org/pipermail/linux-arm-kernel/2016-January/401352.html
>

Since there is already -fpatchable-function-entry option committed by Torsten
to gcc on 25 Jul [1], have you restarted your activities with AArch64 livepatch
support?
If yes, I'm interested in testing of that feature/patches on our hardware

[1] https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=e6c4532a6d0f79b94f327d4f9a067faf3988a852

Thanks,
Ruslan