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-rw-r--r--arch/x86/include/asm/irq_vectors.h47
-rw-r--r--arch/x86/kernel/apic/io_apic.c4
2 files changed, 18 insertions, 33 deletions
diff --git a/arch/x86/include/asm/irq_vectors.h b/arch/x86/include/asm/irq_vectors.h
index 585a42810cf8..8767d99c4f64 100644
--- a/arch/x86/include/asm/irq_vectors.h
+++ b/arch/x86/include/asm/irq_vectors.h
@@ -28,19 +28,22 @@
28#define MCE_VECTOR 0x12 28#define MCE_VECTOR 0x12
29 29
30/* 30/*
31 * IDT vectors usable for external interrupt sources start 31 * IDT vectors usable for external interrupt sources start at 0x20.
32 * at 0x20: 32 * (0x80 is the syscall vector, 0x30-0x3f are for ISA)
33 * hpa said we can start from 0x1f.
34 * 0x1f is documented as reserved. However, the ability for the APIC
35 * to generate vectors starting at 0x10 is documented, as is the
36 * ability for the CPU to receive any vector number as an interrupt.
37 * 0x1f is used for IRQ_MOVE_CLEANUP_VECTOR since that vector needs
38 * an entire privilege level (16 vectors) all by itself at a higher
39 * priority than any actual device vector. Thus, by placing it in the
40 * otherwise-unusable 0x10 privilege level, we avoid wasting a full
41 * 16-vector block.
42 */ 33 */
43#define FIRST_EXTERNAL_VECTOR 0x1f 34#define FIRST_EXTERNAL_VECTOR 0x20
35/*
36 * We start allocating at 0x21 to spread out vectors evenly between
37 * priority levels. (0x80 is the syscall vector)
38 */
39#define VECTOR_OFFSET_START 1
40
41/*
42 * Reserve the lowest usable vector (and hence lowest priority) 0x20 for
43 * triggering cleanup after irq migration. 0x21-0x2f will still be used
44 * for device interrupts.
45 */
46#define IRQ_MOVE_CLEANUP_VECTOR FIRST_EXTERNAL_VECTOR
44 47
45#define IA32_SYSCALL_VECTOR 0x80 48#define IA32_SYSCALL_VECTOR 0x80
46#ifdef CONFIG_X86_32 49#ifdef CONFIG_X86_32
@@ -48,17 +51,7 @@
48#endif 51#endif
49 52
50/* 53/*
51 * Reserve the lowest usable priority level 0x10 - 0x1f for triggering 54 * Vectors 0x30-0x3f are used for ISA interrupts.
52 * cleanup after irq migration.
53 * this overlaps with the reserved range for cpu exceptions so this
54 * will need to be changed to 0x20 - 0x2f if the last cpu exception is
55 * ever allocated.
56 */
57
58#define IRQ_MOVE_CLEANUP_VECTOR FIRST_EXTERNAL_VECTOR
59
60/*
61 * Vectors 0x20-0x2f are used for ISA interrupts.
62 * round up to the next 16-vector boundary 55 * round up to the next 16-vector boundary
63 */ 56 */
64#define IRQ0_VECTOR ((FIRST_EXTERNAL_VECTOR + 16) & ~15) 57#define IRQ0_VECTOR ((FIRST_EXTERNAL_VECTOR + 16) & ~15)
@@ -132,14 +125,6 @@
132 */ 125 */
133#define MCE_SELF_VECTOR 0xeb 126#define MCE_SELF_VECTOR 0xeb
134 127
135/*
136 * First APIC vector available to drivers: (vectors 0x30-0xee). We
137 * start allocating at 0x31 to spread out vectors evenly between
138 * priority levels. (0x80 is the syscall vector)
139 */
140#define FIRST_DEVICE_VECTOR (IRQ15_VECTOR + 1)
141#define VECTOR_OFFSET_START 1
142
143#define NR_VECTORS 256 128#define NR_VECTORS 256
144 129
145#define FPU_IRQ 13 130#define FPU_IRQ 13
diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index e9ba0903e9d5..409f4943dc1a 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -1162,7 +1162,7 @@ __assign_irq_vector(int irq, struct irq_cfg *cfg, const struct cpumask *mask)
1162 * Also, we've got to be careful not to trash gate 1162 * Also, we've got to be careful not to trash gate
1163 * 0x80, because int 0x80 is hm, kind of importantish. ;) 1163 * 0x80, because int 0x80 is hm, kind of importantish. ;)
1164 */ 1164 */
1165 static int current_vector = FIRST_DEVICE_VECTOR + VECTOR_OFFSET_START; 1165 static int current_vector = FIRST_EXTERNAL_VECTOR + VECTOR_OFFSET_START;
1166 static int current_offset = VECTOR_OFFSET_START % 8; 1166 static int current_offset = VECTOR_OFFSET_START % 8;
1167 unsigned int old_vector; 1167 unsigned int old_vector;
1168 int cpu, err; 1168 int cpu, err;
@@ -1199,7 +1199,7 @@ next:
1199 if (vector >= first_system_vector) { 1199 if (vector >= first_system_vector) {
1200 /* If out of vectors on large boxen, must share them. */ 1200 /* If out of vectors on large boxen, must share them. */
1201 offset = (offset + 1) % 8; 1201 offset = (offset + 1) % 8;
1202 vector = FIRST_DEVICE_VECTOR + offset; 1202 vector = FIRST_EXTERNAL_VECTOR + offset;
1203 } 1203 }
1204 if (unlikely(current_vector == vector)) 1204 if (unlikely(current_vector == vector))
1205 continue; 1205 continue;