summaryrefslogtreecommitdiff
path: root/kernel/crash_core.c
diff options
context:
space:
mode:
authorEric DeVolder <eric.devolder@oracle.com>2023-08-14 17:44:43 -0400
committerAndrew Morton <akpm@linux-foundation.org>2023-08-24 16:25:14 -0700
commitea53ad9cf73b6b48608a69e626caeae87e5ddd11 (patch)
tree9673c3e8124a8ade6de5becd538c8bee1a85cbe6 /kernel/crash_core.c
parent88a6f89944216b028d3872b0cec0f51a2f955460 (diff)
x86/crash: add x86 crash hotplug support
When CPU or memory is hot un/plugged, or off/onlined, the crash elfcorehdr, which describes the CPUs and memory in the system, must also be updated. A new elfcorehdr is generated from the available CPUs and memory and replaces the existing elfcorehdr. The segment containing the elfcorehdr is identified at run-time in crash_core:crash_handle_hotplug_event(). No modifications to purgatory (see 'kexec: exclude elfcorehdr from the segment digest') or boot_params (as the elfcorehdr= capture kernel command line parameter pointer remains unchanged and correct) are needed, just elfcorehdr. For kexec_file_load(), the elfcorehdr segment size is based on NR_CPUS and CRASH_MAX_MEMORY_RANGES in order to accommodate a growing number of CPU and memory resources. For kexec_load(), the userspace kexec utility needs to size the elfcorehdr segment in the same/similar manner. To accommodate kexec_load() syscall in the absence of kexec_file_load() syscall support, prepare_elf_headers() and dependents are moved outside of CONFIG_KEXEC_FILE. [eric.devolder@oracle.com: correct unused function build error] Link: https://lkml.kernel.org/r/20230821182644.2143-1-eric.devolder@oracle.com Link: https://lkml.kernel.org/r/20230814214446.6659-6-eric.devolder@oracle.com Signed-off-by: Eric DeVolder <eric.devolder@oracle.com> Reviewed-by: Sourabh Jain <sourabhjain@linux.ibm.com> Acked-by: Hari Bathini <hbathini@linux.ibm.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: Akhil Raj <lf32.dev@gmail.com> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: Borislav Petkov (AMD) <bp@alien8.de> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dave Young <dyoung@redhat.com> Cc: David Hildenbrand <david@redhat.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Mimi Zohar <zohar@linux.ibm.com> Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: "Rafael J. Wysocki" <rafael@kernel.org> Cc: Sean Christopherson <seanjc@google.com> Cc: Takashi Iwai <tiwai@suse.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Thomas Weißschuh <linux@weissschuh.net> Cc: Valentin Schneider <vschneid@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'kernel/crash_core.c')
0 files changed, 0 insertions, 0 deletions