From: Sourabh Jain Date: Tue, 26 Mar 2024 05:54:08 +0000 (+0530) Subject: crash: forward memory_notify arg to arch crash hotplug handler X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=118005713e35a1893c6ee47ab2926cca277737de;p=linux.git crash: forward memory_notify arg to arch crash hotplug handler 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 Acked-by: Baoquan He Acked-by: Hari Bathini Signed-off-by: Michael Ellerman Link: https://msgid.link/20240326055413.186534-2-sourabhjain@linux.ibm.com --- diff --git a/arch/x86/include/asm/kexec.h b/arch/x86/include/asm/kexec.h index 91ca9a9ee3a2b..cb1320ebbc235 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_CPU diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c index e74d0c4286c14..2a682fe863528 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 d33352c2e3865..647e928efee82 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 78b5dc7cee3ab..70fa8111a9d6f 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 @@ out: 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; }