Re: [PATCH] kprobes: Enable tracing for mololithic kernel images

From: "Russell King (Oracle)" <linux@armlinux.org.uk>
To: Jarkko Sakkinen <jarkko@profian.com>
Cc: linux-kernel@vger.kernel.org,
	"Nathaniel McCallum" <nathaniel@profian.com>,
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Subject: Re: [PATCH] kprobes: Enable tracing for mololithic kernel images
Date: Thu, 9 Jun 2022 08:47:38 +0100	[thread overview]
Message-ID: <YqGlmpbx8HTrWmpF@shell.armlinux.org.uk> (raw)
In-Reply-To: <20220608000014.3054333-1-jarkko@profian.com>

On Wed, Jun 08, 2022 at 02:59:27AM +0300, Jarkko Sakkinen wrote:
> diff --git a/arch/arm/kernel/Makefile b/arch/arm/kernel/Makefile
> index 553866751e1a..d2bb954cd54f 100644
> --- a/arch/arm/kernel/Makefile
> +++ b/arch/arm/kernel/Makefile
> @@ -44,6 +44,11 @@ obj-$(CONFIG_CPU_IDLE)		+= cpuidle.o
>  obj-$(CONFIG_ISA_DMA_API)	+= dma.o
>  obj-$(CONFIG_FIQ)		+= fiq.o fiqasm.o
>  obj-$(CONFIG_MODULES)		+= armksyms.o module.o
> +ifeq ($(CONFIG_MODULES),y)
> +obj-y				+= module_alloc.o
> +else
> +obj-$(CONFIG_KPROBES)		+= module_alloc.o
> +endif

Doesn't:

obj-$(CONFIG_MODULES)		+= module_alloc.o
obj-$(CONFIG_KPROBES)		+= module_alloc.o

work just as well? The kbuild modules.rst documentation says:

        The order of files in $(obj-y) is significant.  Duplicates in
        the lists are allowed: the first instance will be linked into
        built-in.a and succeeding instances will be ignored.

so you should be fine... or the documentation is wrong!

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