x86: keep MP_intsrc_info untouched if we do not update mptable

Daniel Exner reported IO-APIC enumeration breakage in linux-next.

Alexey Starikovskiy found out that it might be related to
commit 2944e16b25 "x86: update mptable".

use enable_update_mptable to decide if need check before add mp_irqs array.

Reported-by: Daniel Exner <webmaster@dragonslave.de>
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
index caf4ed7ca069f73c7a5e81f88f4bb77416fb4413..4d370b1c5ae8eda3c70c7fd1af0101fe4d78a09c 100644 (file)
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -1172,6 +1172,9 @@ int mp_config_acpi_gsi(unsigned char number, unsigned int devfn, u8 pin,
        struct mpc_config_intsrc intsrc;
        int ioapic;
 
+       if (!enable_update_mptable)
+               return 0;
+
        /* print the entry should happen on mptable identically */
        intsrc.mpc_type = MP_INTSRC;
        intsrc.mpc_irqtype = mp_INT;

diff --git a/arch/x86/kernel/mpparse.c b/arch/x86/kernel/mpparse.c
index b62ac6ba1410e439e7e49d0abfb8eff9f57458bb..014ac5d90f80a0da0d6fa31998b520d1dd06fb96 100644 (file)
--- a/arch/x86/kernel/mpparse.c
+++ b/arch/x86/kernel/mpparse.c
@@ -34,6 +34,8 @@
 #include <mach_mpparse.h>
 #endif
 
+int enable_update_mptable;
+
 /*
  * Checksum an MP configuration block.
  */
@@ -295,10 +297,11 @@ void MP_intsrc_info(struct mpc_config_intsrc *m)
 
        print_MP_intsrc_info(m);
 
-       for (i = 0; i < mp_irq_entries; i++) {
-               if (!mp_irq_mpc_intsrc_cmp(&mp_irqs[i], m))
-                       return;
-       }
+       if (enable_update_mptable)
+               for (i = 0; i < mp_irq_entries; i++) {
+                       if (!mp_irq_mpc_intsrc_cmp(&mp_irqs[i], m))
+                               return;
+               }
 
        assign_to_mp_irq(m, &mp_irqs[mp_irq_entries]);
        if (++mp_irq_entries == MAX_IRQ_SOURCES)
@@ -1110,8 +1113,6 @@ out:
        return 0;
 }
 
-int __initdata enable_update_mptable;
-
 static int __init update_mptable_setup(char *str)
 {
        enable_update_mptable = 1;

diff --git a/include/asm-x86/mpspec.h b/include/asm-x86/mpspec.h
index b8ba37496e2dde26d18bc746468906f7a5d01162..f48dbca740e475e602327aeb0313cb6bff91505b 100644 (file)
--- a/include/asm-x86/mpspec.h
+++ b/include/asm-x86/mpspec.h
@@ -61,6 +61,7 @@ extern void mp_config_acpi_legacy_irqs(void);
 extern int mp_register_gsi(u32 gsi, int edge_level, int active_high_low);
 extern void MP_intsrc_info(struct mpc_config_intsrc *m);
 #ifdef CONFIG_X86_IO_APIC
+extern int enable_update_mptable;
 extern int mp_config_acpi_gsi(unsigned char number, unsigned int devfn, u8 pin,
                                u32 gsi, int triggering, int polarity);
 #else