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Date:   Tue, 28 Nov 2023 14:34:56 +0100
From:   Alexander Gordeev <agordeev@linux.ibm.com>
To:     Baoquan He <bhe@redhat.com>
Cc:     linux-kernel@vger.kernel.org, kexec@lists.infradead.org,
        x86@kernel.org, akpm@linux-foundation.org, eric_devolder@yahoo.com,
        ignat@cloudflare.com
Subject: Re: [PATCH v2] drivers/base/cpu: crash data showing should depends
 on KEXEC_CORE
Message-ID: <ZWXsgElVV7TH+pte@li-008a6a4c-3549-11b2-a85c-c5cc2836eea2.ibm.com>
References: <20231128055248.659808-1-bhe@redhat.com>
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On Tue, Nov 28, 2023 at 01:52:48PM +0800, Baoquan He wrote:
> After commit 88a6f8994421 ("crash: memory and CPU hotplug sysfs
> attributes"), on x86_64, if only below kernel configs related to kdump
> are set, compiling error are triggered.
> 
> ----
> CONFIG_CRASH_CORE=y
> CONFIG_KEXEC_CORE=y
> CONFIG_CRASH_DUMP=y
> CONFIG_CRASH_HOTPLUG=y
> ------
> 
> ------------------------------------------------------
> drivers/base/cpu.c: In function ‘crash_hotplug_show’:
> drivers/base/cpu.c:309:40: error: implicit declaration of function ‘crash_hotplug_cpu_support’; did you mean ‘crash_hotplug_show’? [-Werror=implicit-function-declaration]
>   309 |         return sysfs_emit(buf, "%d\n", crash_hotplug_cpu_support());
>       |                                        ^~~~~~~~~~~~~~~~~~~~~~~~~
>       |                                        crash_hotplug_show
> cc1: some warnings being treated as errors
> ------------------------------------------------------
> 
> CONFIG_KEXEC is used to enable kexec_load interface, the
> crash_notes/crash_notes_size/crash_hotplug showing depends on
> CONFIG_KEXEC is incorrect. It should depend on KEXEC_CORE instead.
> 
> Fix it now.
> 
> Fixes: commit 88a6f8994421 ("crash: memory and CPU hotplug sysfs attributes")
> Signed-off-by: Baoquan He <bhe@redhat.com>
> ---
>  drivers/base/cpu.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)

Not implemented on s390, but still:
Tested-by: Alexander Gordeev <agordeev@linux.ibm.com>

Thanks!