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-rw-r--r--arch/x86/kernel/apic/apic.c66
-rw-r--r--arch/x86/kernel/apic/io_apic.c20
2 files changed, 67 insertions, 19 deletions
diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index d278736bf774..7f26c9a70a9e 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -75,6 +75,13 @@ unsigned int max_physical_apicid;
physid_mask_t phys_cpu_present_map;
/*
+ * Processor to be disabled specified by kernel parameter
+ * disable_cpu_apicid=<int>, mostly used for the kdump 2nd kernel to
+ * avoid undefined behaviour caused by sending INIT from AP to BSP.
+ */
+static unsigned int disabled_cpu_apicid __read_mostly = BAD_APICID;
+
+/*
* Map cpu index to physical APIC ID
*/
DEFINE_EARLY_PER_CPU_READ_MOSTLY(u16, x86_cpu_to_apicid, BAD_APICID);
@@ -1968,7 +1975,7 @@ __visible void smp_trace_spurious_interrupt(struct pt_regs *regs)
*/
static inline void __smp_error_interrupt(struct pt_regs *regs)
{
- u32 v0, v1;
+ u32 v;
u32 i = 0;
static const char * const error_interrupt_reason[] = {
"Send CS error", /* APIC Error Bit 0 */
@@ -1982,21 +1989,20 @@ static inline void __smp_error_interrupt(struct pt_regs *regs)
};
/* First tickle the hardware, only then report what went on. -- REW */
- v0 = apic_read(APIC_ESR);
apic_write(APIC_ESR, 0);
- v1 = apic_read(APIC_ESR);
+ v = apic_read(APIC_ESR);
ack_APIC_irq();
atomic_inc(&irq_err_count);
- apic_printk(APIC_DEBUG, KERN_DEBUG "APIC error on CPU%d: %02x(%02x)",
- smp_processor_id(), v0 , v1);
+ apic_printk(APIC_DEBUG, KERN_DEBUG "APIC error on CPU%d: %02x",
+ smp_processor_id(), v);
- v1 = v1 & 0xff;
- while (v1) {
- if (v1 & 0x1)
+ v &= 0xff;
+ while (v) {
+ if (v & 0x1)
apic_printk(APIC_DEBUG, KERN_CONT " : %s", error_interrupt_reason[i]);
i++;
- v1 >>= 1;
+ v >>= 1;
}
apic_printk(APIC_DEBUG, KERN_CONT "\n");
@@ -2115,6 +2121,39 @@ int generic_processor_info(int apicid, int version)
phys_cpu_present_map);
/*
+ * boot_cpu_physical_apicid is designed to have the apicid
+ * returned by read_apic_id(), i.e, the apicid of the
+ * currently booting-up processor. However, on some platforms,
+ * it is temporarily modified by the apicid reported as BSP
+ * through MP table. Concretely:
+ *
+ * - arch/x86/kernel/mpparse.c: MP_processor_info()
+ * - arch/x86/mm/amdtopology.c: amd_numa_init()
+ * - arch/x86/platform/visws/visws_quirks.c: MP_processor_info()
+ *
+ * This function is executed with the modified
+ * boot_cpu_physical_apicid. So, disabled_cpu_apicid kernel
+ * parameter doesn't work to disable APs on kdump 2nd kernel.
+ *
+ * Since fixing handling of boot_cpu_physical_apicid requires
+ * another discussion and tests on each platform, we leave it
+ * for now and here we use read_apic_id() directly in this
+ * function, generic_processor_info().
+ */
+ if (disabled_cpu_apicid != BAD_APICID &&
+ disabled_cpu_apicid != read_apic_id() &&
+ disabled_cpu_apicid == apicid) {
+ int thiscpu = num_processors + disabled_cpus;
+
+ pr_warning("APIC: Disabling requested cpu."
+ " Processor %d/0x%x ignored.\n",
+ thiscpu, apicid);
+
+ disabled_cpus++;
+ return -ENODEV;
+ }
+
+ /*
* If boot cpu has not been detected yet, then only allow upto
* nr_cpu_ids - 1 processors and keep one slot free for boot cpu
*/
@@ -2592,3 +2631,12 @@ static int __init lapic_insert_resource(void)
* that is using request_resource
*/
late_initcall(lapic_insert_resource);
+
+static int __init apic_set_disabled_cpu_apicid(char *arg)
+{
+ if (!arg || !get_option(&arg, &disabled_cpu_apicid))
+ return -EINVAL;
+
+ return 0;
+}
+early_param("disable_cpu_apicid", apic_set_disabled_cpu_apicid);
diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index e63a5bd2a78f..a43f068ebec1 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -1142,9 +1142,10 @@ next:
if (test_bit(vector, used_vectors))
goto next;
- for_each_cpu_and(new_cpu, tmp_mask, cpu_online_mask)
- if (per_cpu(vector_irq, new_cpu)[vector] != -1)
+ for_each_cpu_and(new_cpu, tmp_mask, cpu_online_mask) {
+ if (per_cpu(vector_irq, new_cpu)[vector] > VECTOR_UNDEFINED)
goto next;
+ }
/* Found one! */
current_vector = vector;
current_offset = offset;
@@ -1183,7 +1184,7 @@ static void __clear_irq_vector(int irq, struct irq_cfg *cfg)
vector = cfg->vector;
for_each_cpu_and(cpu, cfg->domain, cpu_online_mask)
- per_cpu(vector_irq, cpu)[vector] = -1;
+ per_cpu(vector_irq, cpu)[vector] = VECTOR_UNDEFINED;
cfg->vector = 0;
cpumask_clear(cfg->domain);
@@ -1191,11 +1192,10 @@ static void __clear_irq_vector(int irq, struct irq_cfg *cfg)
if (likely(!cfg->move_in_progress))
return;
for_each_cpu_and(cpu, cfg->old_domain, cpu_online_mask) {
- for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS;
- vector++) {
+ for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS; vector++) {
if (per_cpu(vector_irq, cpu)[vector] != irq)
continue;
- per_cpu(vector_irq, cpu)[vector] = -1;
+ per_cpu(vector_irq, cpu)[vector] = VECTOR_UNDEFINED;
break;
}
}
@@ -1228,12 +1228,12 @@ void __setup_vector_irq(int cpu)
/* Mark the free vectors */
for (vector = 0; vector < NR_VECTORS; ++vector) {
irq = per_cpu(vector_irq, cpu)[vector];
- if (irq < 0)
+ if (irq <= VECTOR_UNDEFINED)
continue;
cfg = irq_cfg(irq);
if (!cpumask_test_cpu(cpu, cfg->domain))
- per_cpu(vector_irq, cpu)[vector] = -1;
+ per_cpu(vector_irq, cpu)[vector] = VECTOR_UNDEFINED;
}
raw_spin_unlock(&vector_lock);
}
@@ -2202,13 +2202,13 @@ asmlinkage void smp_irq_move_cleanup_interrupt(void)
me = smp_processor_id();
for (vector = FIRST_EXTERNAL_VECTOR; vector < NR_VECTORS; vector++) {
- unsigned int irq;
+ int irq;
unsigned int irr;
struct irq_desc *desc;
struct irq_cfg *cfg;
irq = __this_cpu_read(vector_irq[vector]);
- if (irq == -1)
+ if (irq <= VECTOR_UNDEFINED)
continue;
desc = irq_to_desc(irq);