Re: [PATCH v17 1/6] crash: forward memory_notify arg to arch crash hotplug handler
From: Hari Bathini <hbathini@linux.ibm.com>
Date: 2024-03-02 13:20:03
Also in:
kexec
On 26/02/24 2:11 pm, Sourabh Jain wrote:
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.
Acked-by: Hari Bathini <hbathini@linux.ibm.com>
quoted hunk
Signed-off-by: Sourabh Jain <redacted> Acked-by: Baoquan He <redacted> Cc: Akhil Raj <redacted> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Aneesh Kumar K.V <aneesh.kumar@kernel.org> Cc: Borislav Petkov (AMD) <bp@alien8.de> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Christophe Leroy <redacted> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dave Young <redacted> Cc: David Hildenbrand <redacted> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Hari Bathini <hbathini@linux.ibm.com> Cc: Laurent Dufour <redacted> Cc: Mahesh Salgaonkar <mahesh@linux.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Mimi Zohar <zohar@linux.ibm.com> Cc: Naveen N Rao <naveen@kernel.org> Cc: Oscar Salvador <osalvador@suse.de> Cc: Thomas Gleixner <redacted> Cc: Valentin Schneider <vschneid@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: kexec@lists.infradead.org Cc: x86@kernel.org --- arch/x86/include/asm/kexec.h | 2 +- arch/x86/kernel/crash.c | 4 +++- include/linux/crash_core.h | 2 +- kernel/crash_core.c | 14 +++++++------- 4 files changed, 12 insertions(+), 10 deletions(-)diff --git a/arch/x86/include/asm/kexec.h b/arch/x86/include/asm/kexec.h index 91ca9a9ee3a2..cb1320ebbc23 100644 --- a/arch/x86/include/asm/kexec.h +++ b/arch/x86/include/asm/kexec.h@@ -207,7 +207,7 @@ 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_CPUdiff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c index e74d0c4286c1..2a682fe86352 100644 --- a/arch/x86/kernel/crash.c +++ b/arch/x86/kernel/crash.c@@ -432,10 +432,12 @@ 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/crash_core.h b/include/linux/crash_core.h index d33352c2e386..647e928efee8 100644 --- a/include/linux/crash_core.h +++ b/include/linux/crash_core.h@@ -37,7 +37,7 @@ static inline void arch_kexec_unprotect_crashkres(void) { } #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 78b5dc7cee3a..70fa8111a9d6 100644 --- a/kernel/crash_core.c +++ b/kernel/crash_core.c@@ -534,7 +534,7 @@ 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;@@ -596,7 +596,7 @@ 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;@@ -612,17 +612,17 @@ 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;@@ -635,13 +635,13 @@ 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; }