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> } > > -static int > -wakeup_secondary_cpu_via_init(int phys_apicid, unsigned long start_eip) > +static void send_init_sequence(int phys_apicid) > { > - unsigned long send_status = 0, accept_status = 0; > - int maxlvt, num_starts, j; > - > - maxlvt = lapic_get_maxlvt(); > + int maxlvt = lapic_get_maxlvt(); > > - /* > - * Be paranoid about clearing APIC errors. > - */ > + /* Be paranoid about clearing APIC errors. */ > if (APIC_INTEGRATED(boot_cpu_apic_version)) { > - if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */ > + /* Due to the Pentium erratum 3AP. */ > + if (maxlvt > 3) > apic_write(APIC_ESR, 0); > apic_read(APIC_ESR); > } > > - pr_debug("Asserting INIT\n"); > - > - /* > - * Turn INIT on target chip > - */ > - /* > - * Send IPI > - */ > - apic_icr_write(APIC_INT_LEVELTRIG | APIC_INT_ASSERT | APIC_DM_INIT, > - phys_apicid); > - > - pr_debug("Waiting for send to finish...\n"); > - send_status = safe_apic_wait_icr_idle(); > + /* Assert INIT on the target CPU */ > + apic_icr_write(APIC_INT_LEVELTRIG | APIC_INT_ASSERT | APIC_DM_INIT, phys_apicid); > + safe_apic_wait_icr_idle(); > > udelay(init_udelay); > > - pr_debug("Deasserting INIT\n"); > - > - /* Target chip */ > - /* Send IPI */ > + /* Deassert INIT on the target CPU */ > apic_icr_write(APIC_INT_LEVELTRIG | APIC_DM_INIT, phys_apicid); > + safe_apic_wait_icr_idle(); > +} > + > +/* > + * Wake up AP by INIT, INIT, STARTUP sequence. > + */ > +static int wakeup_secondary_cpu_via_init(int phys_apicid, unsigned long start_eip) > +{ > + unsigned long send_status = 0, accept_status = 0; > + int maxlvt, num_starts, j; > + > + preempt_disable(); This seems like an unbalanced preempt disable.. > > - pr_debug("Waiting for send to finish...\n"); > - send_status = safe_apic_wait_icr_idle(); > + send_init_sequence(phys_apicid); > > mb(); > > --Mika