From: Denys Vlasenko Date: Tue, 13 Sep 2016 18:12:32 +0000 (+0200) Subject: x86/apic: Get rid of apic_version[] array X-Git-Url: http://git.efficios.com/?p=deliverable%2Flinux.git;a=commitdiff_plain;h=720aa4d9794f14940c38ada893ab9f2a2107b562 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 CC: Andy Lutomirski CC: Borislav Petkov CC: Brian Gerst CC: Mike Travis Link: http://lkml.kernel.org/r/20160913181232.30815-1-dvlasenk@redhat.com Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman --- diff --git a/arch/x86/include/asm/mpspec.h b/arch/x86/include/asm/mpspec.h index b07233b64578..c2f94dcc92ce 100644 --- a/arch/x86/include/asm/mpspec.h +++ b/arch/x86/include/asm/mpspec.h @@ -6,7 +6,6 @@ #include #include -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 90d84c3eee53..fbd19444403f 100644 --- a/arch/x86/kernel/acpi/boot.c +++ b/arch/x86/kernel/acpi/boot.c @@ -182,7 +182,7 @@ static int acpi_register_lapic(int id, u32 acpiid, u8 enabled) } if (boot_cpu_physical_apicid != -1U) - ver = apic_version[boot_cpu_physical_apicid]; + ver = boot_cpu_apic_version; cpu = generic_processor_info(id, ver); if (cpu >= 0) diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c index f3e9b2df4b16..076c315cdf18 100644 --- 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. */ @@ -1816,8 +1818,7 @@ 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)); } } @@ -1832,13 +1833,10 @@ 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 */ @@ -2130,11 +2128,10 @@ 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); @@ -2277,7 +2274,7 @@ 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 7491f417a8e4..48e6d84f173e 100644 --- a/arch/x86/kernel/apic/io_apic.c +++ b/arch/x86/kernel/apic/io_apic.c @@ -1593,7 +1593,7 @@ 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(); } @@ -2423,7 +2423,7 @@ 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 7c43e716c158..563096267ca2 100644 --- a/arch/x86/kernel/apic/probe_32.c +++ b/arch/x86/kernel/apic/probe_32.c @@ -152,7 +152,7 @@ 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 4296beb8fdd3..75a045424be7 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -690,7 +690,7 @@ 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); @@ -717,7 +717,7 @@ 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); @@ -756,7 +756,7 @@ 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; @@ -994,7 +994,7 @@ 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); } @@ -1249,7 +1249,7 @@ 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",