The patch titled Subject: drivers/base/cpu: crash data showing should depends on KEXEC_CORE has been added to the -mm mm-hotfixes-unstable branch. Its filename is drivers-base-cpu-crash-data-showing-should-depends-on-kexec_core.patch

This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches...

This patch will later appear in the mm-hotfixes-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------ From: Baoquan He bhe@redhat.com Subject: drivers/base/cpu: crash data showing should depends on KEXEC_CORE Date: Tue, 28 Nov 2023 13:52:48 +0800

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.

Link: https://lkml.kernel.org/r/20231128055248.659808-1-bhe@redhat.com Fixes: commit 88a6f8994421 ("crash: memory and CPU hotplug sysfs attributes") Signed-off-by: Baoquan He bhe@redhat.com Tested-by: Ignat Korchagin ignat@cloudflare.com [compile-time only] Tested-by: Alexander Gordeev agordeev@linux.ibm.com Reviewed-by: Eric DeVolder eric_devolder@yahoo.com Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

drivers/base/cpu.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)

--- a/drivers/base/cpu.c~drivers-base-cpu-crash-data-showing-should-depends-on-kexec_core +++ a/drivers/base/cpu.c @@ -144,7 +144,7 @@ static DEVICE_ATTR(release, S_IWUSR, NUL #endif /* CONFIG_ARCH_CPU_PROBE_RELEASE */ #endif /* CONFIG_HOTPLUG_CPU */

-#ifdef CONFIG_KEXEC +#ifdef CONFIG_KEXEC_CORE #include <linux/kexec.h>

static ssize_t crash_notes_show(struct device *dev, @@ -189,14 +189,14 @@ static const struct attribute_group cras #endif

static const struct attribute_group *common_cpu_attr_groups[] = { -#ifdef CONFIG_KEXEC +#ifdef CONFIG_KEXEC_CORE &crash_note_cpu_attr_group, #endif NULL };

static const struct attribute_group *hotplugable_cpu_attr_groups[] = { -#ifdef CONFIG_KEXEC +#ifdef CONFIG_KEXEC_CORE &crash_note_cpu_attr_group, #endif NULL _

Patches currently in -mm which might be from bhe@redhat.com are

drivers-base-cpu-crash-data-showing-should-depends-on-kexec_core.patch resource-add-walk_system_ram_res_rev.patch kexec_file-load-kernel-at-top-of-system-ram-if-required.patch