Date: Wed, 7 Dec 2016 16:05:25 +0100
From: Petr Mladek <pmladek@suse.com>
To: Abel Vesa <abelvesa@linux.com>
Cc: linux@armlinux.org.uk, jpoimboe@redhat.com, jeyu@redhat.com,
        jikos@kernel.org, mbenes@suse.cz, rostedt@goodmis.org,
        mingo@redhat.com, gregkh@linuxfoundation.org, geert+renesas@glider.be,
        davem@davemloft.net, akpm@linux-foundation.org,
        emil.l.velikov@gmail.com, mchehab@kernel.org, linux@roeck-us.net,
        ard.biesheuvel@linaro.org, jens.wiklander@linaro.org,
        jean-philippe.brucker@arm.com, viro@zeniv.linux.org.uk,
        stefano.stabellini@eu.citrix.com, chris.brandt@renesas.com,
        linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
        live-patching@vger.kernel.org
Subject: Re: [PATCH 6/7] arm: Add livepatch to build if CONFIG_LIVEPATCH
Message-ID: <20161207150525.GD13288@linux.suse>
References: <1481043967-15602-1-git-send-email-abelvesa@linux.com>
 <1481043967-15602-7-git-send-email-abelvesa@linux.com>
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On Tue 2016-12-06 17:06:06, Abel Vesa wrote:
> Necessary livepatch file added to makefile.
> 
> Signed-off-by: Abel Vesa <abelvesa@linux.com>
> ---
>  arch/arm/kernel/Makefile | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile
> index ad325a8..9e70220 100644
> --- a/arch/arm/kernel/Makefile
> +++ b/arch/arm/kernel/Makefile
> @@ -48,6 +48,7 @@ obj-$(CONFIG_HAVE_ARM_TWD)	+= smp_twd.o
>  obj-$(CONFIG_ARM_ARCH_TIMER)	+= arch_timer.o
>  obj-$(CONFIG_FUNCTION_TRACER)	+= entry-ftrace.o
>  obj-$(CONFIG_DYNAMIC_FTRACE)	+= ftrace.o insn.o
> +obj-$(CONFIG_LIVEPATCH)		+= livepatch.o

It is strange that you add a source file in one patch and make it
build in a much later patch.

I suggest to restructure the entire patchset a bit. Please, first
add support for FTRACE_WITH_REGS. It makes sense on its own.
Then add the livepatch support on top of it.

Otherwise, it is not necessary to send v2 immediately for such
non-trivial code. There might be more people that would want
to look at it and it might take days until they find a time.
It is always better to collect some feedback, think about it
over night(s). Every question often opens many other questions
and it usually takes some time until all settles down into
a good picture again.

Best Regards,
Petr