x86/apic: Get rid of apic_version[] array

commit cff9ab2b291e64259d97add48fe073c081afe4e2 upstream.

The array has a size of MAX_LOCAL_APIC, which can be as large as 32k, so it
can consume up to 128k.

The array has been there forever and was never used for anything useful
other than a version mismatch check which was introduced in 2009.

There is no reason to store the version in an array. The kernel is not
prepared to handle different APIC versions anyway, so the real important
part is to detect a version mismatch and warn about it, which can be done
with a single variable as well.

[ tglx: Massaged changelog ]

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: Andy Lutomirski <luto@amacapital.net>
CC: Borislav Petkov <bp@alien8.de>
CC: Brian Gerst <brgerst@gmail.com>
CC: Mike Travis <travis@sgi.com>
Link: http://lkml.kernel.org/r/20160913181232.30815-1-dvlasenk@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/x86/include/asm/mpspec.h b/arch/x86/include/asm/mpspec.h
index b07233b64578721668b6d5d06903c5b148bd169d..c2f94dcc92ce8eb110c05040d78ff806beb3824a 100644 (file)
--- a/arch/x86/include/asm/mpspec.h
+++ b/arch/x86/include/asm/mpspec.h
@@ -6,7 +6,6 @@
 #include <asm/x86_init.h>
 #include <asm/apicdef.h>
 
-extern int apic_version[];
 extern int pic_mode;
 
 #ifdef CONFIG_X86_32
@@ -40,6 +39,7 @@ extern int mp_bus_id_to_type[MAX_MP_BUSSES];
 extern DECLARE_BITMAP(mp_bus_not_pci, MAX_MP_BUSSES);
 
 extern unsigned int boot_cpu_physical_apicid;
+extern u8 boot_cpu_apic_version;
 extern unsigned long mp_lapic_addr;
 
 #ifdef CONFIG_X86_LOCAL_APIC

diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
index 9414f84584e40f347c0b9bfbae31fd4688c76edc..8e6e8bc8cd9fcc328a3e115b40ff81e010ca86cd 100644 (file)
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -180,7 +180,7 @@ static int acpi_register_lapic(int id, u8 enabled)
        }
 
        if (boot_cpu_physical_apicid != -1U)
-               ver = apic_version[boot_cpu_physical_apicid];
+               ver = boot_cpu_apic_version;
 
        return generic_processor_info(id, ver);
 }

diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index b15e1c158bdafcae9e694358a1d58289c1f36f4e..cc7bc8bfd890479bbb51cd22c865f0bdf759f33e 100644 (file)
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -64,6 +64,8 @@ unsigned disabled_cpus;
 unsigned int boot_cpu_physical_apicid = -1U;
 EXPORT_SYMBOL_GPL(boot_cpu_physical_apicid);
 
+u8 boot_cpu_apic_version;
+
 /*
  * The highest APIC ID seen during enumeration.
  */
@@ -1790,8 +1792,7 @@ void __init init_apic_mappings(void)
                 * since smp_sanity_check is prepared for such a case
                 * and disable smp mode
                 */
-               apic_version[new_apicid] =
-                        GET_APIC_VERSION(apic_read(APIC_LVR));
+               boot_cpu_apic_version = GET_APIC_VERSION(apic_read(APIC_LVR));
        }
 }
 
@@ -1806,13 +1807,10 @@ void __init register_lapic_address(unsigned long address)
        }
        if (boot_cpu_physical_apicid == -1U) {
                boot_cpu_physical_apicid  = read_apic_id();
-               apic_version[boot_cpu_physical_apicid] =
-                        GET_APIC_VERSION(apic_read(APIC_LVR));
+               boot_cpu_apic_version = GET_APIC_VERSION(apic_read(APIC_LVR));
        }
 }
 
-int apic_version[MAX_LOCAL_APIC];
-
 /*
  * Local APIC interrupts
  */
@@ -2102,11 +2100,10 @@ int generic_processor_info(int apicid, int version)
                           cpu, apicid);
                version = 0x10;
        }
-       apic_version[apicid] = version;
 
-       if (version != apic_version[boot_cpu_physical_apicid]) {
+       if (version != boot_cpu_apic_version) {
                pr_warning("BIOS bug: APIC version mismatch, boot CPU: %x, CPU %d: version %x\n",
-                       apic_version[boot_cpu_physical_apicid], cpu, version);
+                       boot_cpu_apic_version, cpu, version);
        }
 
        physid_set(apicid, phys_cpu_present_map);
@@ -2249,7 +2246,7 @@ int __init APIC_init_uniprocessor(void)
         * Complain if the BIOS pretends there is one.
         */
        if (!boot_cpu_has(X86_FEATURE_APIC) &&
-           APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid])) {
+           APIC_INTEGRATED(boot_cpu_apic_version)) {
                pr_err("BIOS bug, local APIC 0x%x not detected!...\n",
                        boot_cpu_physical_apicid);
                return -1;

diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index 446702ed99dca3edf5a8a48cccb6c2475ae9e85f..fbfb2446de58669636fcf2cef3b1782e68088d0a 100644 (file)
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -1592,7 +1592,7 @@ void __init setup_ioapic_ids_from_mpc(void)
         * no meaning without the serial APIC bus.
         */
        if (!(boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)
-               || APIC_XAPIC(apic_version[boot_cpu_physical_apicid]))
+               || APIC_XAPIC(boot_cpu_apic_version))
                return;
        setup_ioapic_ids_from_mpc_nocheck();
 }
@@ -2422,7 +2422,7 @@ static int io_apic_get_unique_id(int ioapic, int apic_id)
 static u8 io_apic_unique_id(int idx, u8 id)
 {
        if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) &&
-           !APIC_XAPIC(apic_version[boot_cpu_physical_apicid]))
+           !APIC_XAPIC(boot_cpu_apic_version))
                return io_apic_get_unique_id(idx, id);
        else
                return id;

diff --git a/arch/x86/kernel/apic/probe_32.c b/arch/x86/kernel/apic/probe_32.c
index f316e34abb42bef31fbf8948bb1cdd8c4491fcbe..49da80cf6a774b05faf81526406706c763e9d7f9 100644 (file)
--- a/arch/x86/kernel/apic/probe_32.c
+++ b/arch/x86/kernel/apic/probe_32.c
@@ -153,7 +153,7 @@ early_param("apic", parse_apic);
 
 void __init default_setup_apic_routing(void)
 {
-       int version = apic_version[boot_cpu_physical_apicid];
+       int version = boot_cpu_apic_version;
 
        if (num_possible_cpus() > 8) {
                switch (boot_cpu_data.x86_vendor) {

diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index fafe8b923cac2d27da4189e6be9a2761bfcd6d01..736f6100fcc770e5b394e629f978d1fa829e5d17 100644 (file)
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -676,7 +676,7 @@ wakeup_secondary_cpu_via_nmi(int apicid, unsigned long start_eip)
         * Give the other CPU some time to accept the IPI.
         */
        udelay(200);
-       if (APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid])) {
+       if (APIC_INTEGRATED(boot_cpu_apic_version)) {
                maxlvt = lapic_get_maxlvt();
                if (maxlvt > 3)                 /* Due to the Pentium erratum 3AP.  */
                        apic_write(APIC_ESR, 0);
@@ -703,7 +703,7 @@ wakeup_secondary_cpu_via_init(int phys_apicid, unsigned long start_eip)
        /*
         * Be paranoid about clearing APIC errors.
         */
-       if (APIC_INTEGRATED(apic_version[phys_apicid])) {
+       if (APIC_INTEGRATED(boot_cpu_apic_version)) {
                if (maxlvt > 3)         /* Due to the Pentium erratum 3AP.  */
                        apic_write(APIC_ESR, 0);
                apic_read(APIC_ESR);
@@ -742,7 +742,7 @@ wakeup_secondary_cpu_via_init(int phys_apicid, unsigned long start_eip)
         * Determine this based on the APIC version.
         * If we don't have an integrated APIC, don't send the STARTUP IPIs.
         */
-       if (APIC_INTEGRATED(apic_version[phys_apicid]))
+       if (APIC_INTEGRATED(boot_cpu_apic_version))
                num_starts = 2;
        else
                num_starts = 0;
@@ -980,7 +980,7 @@ static int do_boot_cpu(int apicid, int cpu, struct task_struct *idle)
                /*
                 * Be paranoid about clearing APIC errors.
                */
-               if (APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid])) {
+               if (APIC_INTEGRATED(boot_cpu_apic_version)) {
                        apic_write(APIC_ESR, 0);
                        apic_read(APIC_ESR);
                }
@@ -1235,7 +1235,7 @@ static int __init smp_sanity_check(unsigned max_cpus)
        /*
         * If we couldn't find a local APIC, then get out of here now!
         */
-       if (APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid]) &&
+       if (APIC_INTEGRATED(boot_cpu_apic_version) &&
            !boot_cpu_has(X86_FEATURE_APIC)) {
                if (!disable_apic) {
                        pr_err("BIOS bug, local APIC #%d not detected!...\n",