[PATCH v14 1/6] crash: forward memory_notify arg to arch crash hotplug handler
Sourabh Jain
sourabhjain at linux.ibm.com
Mon Dec 11 00:30:51 PST 2023
In the event of memory hotplug or online/offline events, the crash
memory hotplug notifier `crash_memhp_notifier()` receives a
`memory_notify` object but doesn't forward that object to the
generic and architecture-specific crash hotplug handler.
The `memory_notify` object contains the starting PFN (Page Frame Number)
and the number of pages in the hot-removed memory. This information is
necessary for architectures like PowerPC to update/recreate the kdump
image, specifically `elfcorehdr`.
So update the function signature of `crash_handle_hotplug_event()` and
`arch_crash_handle_hotplug_event()` to accept the `memory_notify` object
as an argument from crash memory hotplug notifier.
Since no such object is available in the case of CPU hotplug event, the
crash CPU hotplug notifier `crash_cpuhp_online()` passes NULL to the
crash hotplug handler.
Signed-off-by: Sourabh Jain <sourabhjain at linux.ibm.com>
Cc: Akhil Raj <lf32.dev at gmail.com>
Cc: Andrew Morton <akpm at linux-foundation.org>
Cc: Aneesh Kumar K.V <aneesh.kumar at kernel.org>
Cc: Baoquan He <bhe at redhat.com>
Cc: Borislav Petkov (AMD) <bp at alien8.de>
Cc: Boris Ostrovsky <boris.ostrovsky at oracle.com>
Cc: Christophe Leroy <christophe.leroy at csgroup.eu>
Cc: Dave Hansen <dave.hansen at linux.intel.com>
Cc: Dave Young <dyoung at redhat.com>
Cc: David Hildenbrand <david at redhat.com>
Cc: Eric DeVolder <eric.devolder at oracle.com>
Cc: Greg Kroah-Hartman <gregkh at linuxfoundation.org>
Cc: Hari Bathini <hbathini at linux.ibm.com>
Cc: Laurent Dufour <laurent.dufour at fr.ibm.com>
Cc: Mahesh Salgaonkar <mahesh at linux.ibm.com>
Cc: Michael Ellerman <mpe at ellerman.id.au>
Cc: Mimi Zohar <zohar at linux.ibm.com>
Cc: Naveen N Rao <naveen at kernel.org>
Cc: Oscar Salvador <osalvador at suse.de>
Cc: Thomas Gleixner <tglx at linutronix.de>
Cc: Valentin Schneider <vschneid at redhat.com>
Cc: Vivek Goyal <vgoyal at redhat.com>
Cc: kexec at lists.infradead.org
Cc: x86 at kernel.org
---
arch/x86/include/asm/kexec.h | 2 +-
arch/x86/kernel/crash.c | 3 ++-
include/linux/kexec.h | 2 +-
kernel/crash_core.c | 14 +++++++-------
4 files changed, 11 insertions(+), 10 deletions(-)
diff --git a/arch/x86/include/asm/kexec.h b/arch/x86/include/asm/kexec.h
index c9f6a6c5de3c..9bb6607e864e 100644
--- a/arch/x86/include/asm/kexec.h
+++ b/arch/x86/include/asm/kexec.h
@@ -208,7 +208,7 @@ int arch_kimage_file_post_load_cleanup(struct kimage *image);
extern void kdump_nmi_shootdown_cpus(void);
#ifdef CONFIG_CRASH_HOTPLUG
-void arch_crash_handle_hotplug_event(struct kimage *image);
+void arch_crash_handle_hotplug_event(struct kimage *image, void *arg);
#define arch_crash_handle_hotplug_event arch_crash_handle_hotplug_event
#ifdef CONFIG_HOTPLUG_CPU
diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c
index c92d88680dbf..0d7b2657beb6 100644
--- a/arch/x86/kernel/crash.c
+++ b/arch/x86/kernel/crash.c
@@ -428,10 +428,11 @@ unsigned int arch_crash_get_elfcorehdr_size(void)
/**
* arch_crash_handle_hotplug_event() - Handle hotplug elfcorehdr changes
* @image: a pointer to kexec_crash_image
+ * @arg: struct memory_notify handler for memory hotplug case and NULL for CPU hotplug case.
*
* Prepare the new elfcorehdr and replace the existing elfcorehdr.
*/
-void arch_crash_handle_hotplug_event(struct kimage *image)
+void arch_crash_handle_hotplug_event(struct kimage *image, void *arg)
{
void *elfbuf = NULL, *old_elfcorehdr;
unsigned long nr_mem_ranges;
diff --git a/include/linux/kexec.h b/include/linux/kexec.h
index 8227455192b7..ee28c09a7fb0 100644
--- a/include/linux/kexec.h
+++ b/include/linux/kexec.h
@@ -483,7 +483,7 @@ static inline void arch_kexec_pre_free_pages(void *vaddr, unsigned int pages) {
#endif
#ifndef arch_crash_handle_hotplug_event
-static inline void arch_crash_handle_hotplug_event(struct kimage *image) { }
+static inline void arch_crash_handle_hotplug_event(struct kimage *image, void *arg) { }
#endif
int crash_check_update_elfcorehdr(void);
diff --git a/kernel/crash_core.c b/kernel/crash_core.c
index efe87d501c8c..b9190265fe52 100644
--- a/kernel/crash_core.c
+++ b/kernel/crash_core.c
@@ -935,7 +935,7 @@ int crash_check_update_elfcorehdr(void)
* list of segments it checks (since the elfcorehdr changes and thus
* would require an update to purgatory itself to update the digest).
*/
-static void crash_handle_hotplug_event(unsigned int hp_action, unsigned int cpu)
+static void crash_handle_hotplug_event(unsigned int hp_action, unsigned int cpu, void *arg)
{
struct kimage *image;
@@ -997,7 +997,7 @@ static void crash_handle_hotplug_event(unsigned int hp_action, unsigned int cpu)
image->hp_action = hp_action;
/* Now invoke arch-specific update handler */
- arch_crash_handle_hotplug_event(image);
+ arch_crash_handle_hotplug_event(image, arg);
/* No longer handling a hotplug event */
image->hp_action = KEXEC_CRASH_HP_NONE;
@@ -1013,17 +1013,17 @@ static void crash_handle_hotplug_event(unsigned int hp_action, unsigned int cpu)
crash_hotplug_unlock();
}
-static int crash_memhp_notifier(struct notifier_block *nb, unsigned long val, void *v)
+static int crash_memhp_notifier(struct notifier_block *nb, unsigned long val, void *arg)
{
switch (val) {
case MEM_ONLINE:
crash_handle_hotplug_event(KEXEC_CRASH_HP_ADD_MEMORY,
- KEXEC_CRASH_HP_INVALID_CPU);
+ KEXEC_CRASH_HP_INVALID_CPU, arg);
break;
case MEM_OFFLINE:
crash_handle_hotplug_event(KEXEC_CRASH_HP_REMOVE_MEMORY,
- KEXEC_CRASH_HP_INVALID_CPU);
+ KEXEC_CRASH_HP_INVALID_CPU, arg);
break;
}
return NOTIFY_OK;
@@ -1036,13 +1036,13 @@ static struct notifier_block crash_memhp_nb = {
static int crash_cpuhp_online(unsigned int cpu)
{
- crash_handle_hotplug_event(KEXEC_CRASH_HP_ADD_CPU, cpu);
+ crash_handle_hotplug_event(KEXEC_CRASH_HP_ADD_CPU, cpu, NULL);
return 0;
}
static int crash_cpuhp_offline(unsigned int cpu)
{
- crash_handle_hotplug_event(KEXEC_CRASH_HP_REMOVE_CPU, cpu);
+ crash_handle_hotplug_event(KEXEC_CRASH_HP_REMOVE_CPU, cpu, NULL);
return 0;
}
--
2.41.0
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