+ drivers-base-cpu-crash-data-showing-should-depends-on-kexec_core.patch added to mm-hotfixes-unstable branch

+ drivers-base-cpu-crash-data-showing-should-depends-on-kexec_core.patch added to mm-hotfixes-unstable branch

[Andrew Morton]

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/drivers-base-cpu-crash-data-showing-should-depends-on-kexec_core.patch

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