1 files changed, 8 insertions, 0 deletions

diff --git a/arch/i386/kernel/apic.c b/arch/i386/kernel/apic.c
index 013b85df18c6..3d4b2f3d116a 100644
--- a/arch/i386/kernel/apic.c
+++ b/arch/i386/kernel/apic.c
@@ -1341,6 +1341,14 @@ int __init APIC_init_uniprocessor (void)
 
         connect_bsp_APIC();
 
+        /*
+         * Hack: In case of kdump, after a crash, kernel might be booting
+         * on a cpu with non-zero lapic id. But boot_cpu_physical_apicid
+         * might be zero if read from MP tables. Get it from LAPIC.
+         */
+#ifdef CONFIG_CRASH_DUMP
+        boot_cpu_physical_apicid = GET_APIC_ID(apic_read(APIC_ID));
+#endif
         phys_cpu_present_map = physid_mask_of_physid(boot_cpu_physical_apicid);
 
         setup_local_APIC();