1. 25 Jul, 2019 1 commit
  2. 17 Jun, 2019 1 commit
    • Peter Zijlstra's avatar
      x86/percpu: Relax smp_processor_id() · 9ed7d75b
      Peter Zijlstra authored
      Nadav reported that since this_cpu_read() became asm-volatile, many
      smp_processor_id() users generated worse code due to the extra
      However since smp_processor_id() is reading a stable value, we can use
      While this does reduce text size somewhat, this mostly results in code
      movement to .text.unlikely as a result of more/larger .cold.
      subfunctions. Less text on the hotpath is good for I$.
        $ ./compare.sh defconfig-build1 defconfig-build2 vmlinux.o
        setup_APIC_ibs                                             90         98   -12,+20
        force_ibs_eilvt_setup                                     400        413   -57,+70
        pci_serr_error                                            109        104   -54,+49
        pci_serr_error                                            109        104   -54,+49
        unknown_nmi_error                                         125        120   -76,+71
        unknown_nmi_error                                         125        120   -76,+71
        io_check_error                                            125        132   -97,+104
        intel_thermal_interrupt                                   730        822   +92,+0
        intel_init_thermal                                        951        945   -6,+0
        generic_get_mtrr                                          301        294   -7,+0
        generic_get_mtrr                                          301        294   -7,+0
        generic_set_all                                           749        754   -44,+49
        get_fixed_ranges                                          352        360   -41,+49
        x86_acpi_suspend_lowlevel                                 369        363   -6,+0
        check_tsc_sync_source                                     412        412   -71,+71
        irq_migrate_all_off_this_cpu                              662        674   -14,+26
        clocksource_watchdog                                      748        748   -113,+113
        __perf_event_account_interrupt                            204        197   -7,+0
        attempt_merge                                            1748       1741   -7,+0
        intel_guc_send_ct                                        1424       1409   -15,+0
        __fini_doorbell                                           235        231   -4,+0
        bdw_set_cdclk                                             928        923   -5,+0
        gen11_dsi_disable                                        1571       1556   -15,+0
        gmbus_wait                                                493        488   -5,+0
        md_make_request                                           376        369   -7,+0
        __split_and_process_bio                                   543        536   -7,+0
        delay_tsc                                                  96         89   -7,+0
        hsw_disable_pc8                                           696        691   -5,+0
        tsc_verify_tsc_adjust                                     215        228   -22,+35
        cpuidle_driver_unref                                       56         49   -7,+0
        blk_account_io_completion                                 159        148   -11,+0
        mtrr_wrmsr                                                 95         99   -29,+33
        __intel_wait_for_register_fw                              401        419   +18,+0
        cpuidle_driver_ref                                         43         36   -7,+0
        cpuidle_get_driver                                         15          8   -7,+0
        blk_account_io_done                                       535        528   -7,+0
        irq_migrate_all_off_this_cpu                              662        674   -14,+26
        check_tsc_sync_source                                     412        412   -71,+71
        irq_wait_for_poll                                         170        163   -7,+0
        generic_end_io_acct                                       329        322   -7,+0
        x86_acpi_suspend_lowlevel                                 369        363   -6,+0
        nohz_balance_enter_idle                                   198        191   -7,+0
        generic_start_io_acct                                     254        247   -7,+0
        blk_account_io_start                                      341        334   -7,+0
        perf_event_task_tick                                      682        675   -7,+0
        intel_init_thermal                                        951        945   -6,+0
        amd_e400_c1e_apic_setup                                    47         51   -28,+32
        setup_APIC_eilvt                                          350        328   -22,+0
        hsw_enable_pc8                                           1611       1605   -6,+0
                                                     total   12985947   12985892   -994,+939
      Reported-by: default avatarNadav Amit <nadav.amit@gmail.com>
      Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
  3. 23 May, 2019 1 commit
  4. 17 Apr, 2019 1 commit
    • Thomas Gleixner's avatar
      x86/irq/32: Handle irq stack allocation failure proper · 66c7ceb4
      Thomas Gleixner authored
      irq_ctx_init() crashes hard on page allocation failures. While that's ok
      during early boot, it's just wrong in the CPU hotplug bringup code.
      Check the page allocation failure and return -ENOMEM and handle it at the
      call sites. On early boot the only way out is to BUG(), but on CPU hotplug
      there is no reason to crash, so just abort the operation.
      Rename the function to something more sensible while at it.
      Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
      Signed-off-by: default avatarBorislav Petkov <bp@suse.de>
      Cc: Alison Schofield <alison.schofield@intel.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Anshuman Khandual <anshuman.khandual@arm.com>
      Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Juergen Gross <jgross@suse.com>
      Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
      Cc: Nicolai Stange <nstange@suse.de>
      Cc: Pu Wen <puwen@hygon.cn>
      Cc: Sean Christopherson <sean.j.christopherson@intel.com>
      Cc: Shaokun Zhang <zhangshaokun@hisilicon.com>
      Cc: Stefano Stabellini <sstabellini@kernel.org>
      Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
      Cc: x86-ml <x86@kernel.org>
      Cc: xen-devel@lists.xenproject.org
      Cc: Yazen Ghannam <yazen.ghannam@amd.com>
      Cc: Yi Wang <wang.yi59@zte.com.cn>
      Cc: Zhenzhong Duan <zhenzhong.duan@oracle.com>
      Link: https://lkml.kernel.org/r/20190414160146.089060584@linutronix.de
  5. 23 Nov, 2018 1 commit
    • Yi Wang's avatar
      x86/headers: Fix -Wmissing-prototypes warning · 89f579ce
      Yi Wang authored
      When building the kernel with W=1 we get a lot of -Wmissing-prototypes
      warnings, which are trivial in nature and easy to fix - and which may
      mask some real future bugs if the prototypes get out of sync with
      the function definition.
      This patch fixes most of -Wmissing-prototypes warnings which
      are in the root directory of arch/x86/kernel, not including
      the subdirectories.
      These are the warnings fixed in this patch:
        arch/x86/kernel/signal.c:865:17: warning: no previous prototype for ‘sys32_x32_rt_sigreturn’ [-Wmissing-prototypes]
        arch/x86/kernel/signal_compat.c:164:6: warning: no previous prototype for ‘sigaction_compat_abi’ [-Wmissing-prototypes]
        arch/x86/kernel/traps.c:625:46: warning: no previous prototype for ‘sync_regs’ [-Wmissing-prototypes]
        arch/x86/kernel/traps.c:640:24: warning: no previous prototype for ‘fixup_bad_iret’ [-Wmissing-prototypes]
        arch/x86/kernel/traps.c:929:13: warning: no previous prototype for ‘trap_init’ [-Wmissing-prototypes]
        arch/x86/kernel/irq.c:270:28: warning: no previous prototype for ‘smp_x86_platform_ipi’ [-Wmissing-prototypes]
        arch/x86/kernel/irq.c:301:16: warning: no previous prototype for ‘smp_kvm_posted_intr_ipi’ [-Wmissing-prototypes]
        arch/x86/kernel/irq.c:314:16: warning: no previous prototype for ‘smp_kvm_posted_intr_wakeup_ipi’ [-Wmissing-prototypes]
        arch/x86/kernel/irq.c:328:16: warning: no previous prototype for ‘smp_kvm_posted_intr_nested_ipi’ [-Wmissing-prototypes]
        arch/x86/kernel/irq_work.c:16:28: warning: no previous prototype for ‘smp_irq_work_interrupt’ [-Wmissing-prototypes]
        arch/x86/kernel/irqinit.c:79:13: warning: no previous prototype for ‘init_IRQ’ [-Wmissing-prototypes]
        arch/x86/kernel/quirks.c:672:13: warning: no previous prototype for ‘early_platform_quirks’ [-Wmissing-prototypes]
        arch/x86/kernel/tsc.c:1499:15: warning: no previous prototype for ‘calibrate_delay_is_known’ [-Wmissing-prototypes]
        arch/x86/kernel/process.c:653:13: warning: no previous prototype for ‘arch_post_acpi_subsys_init’ [-Wmissing-prototypes]
        arch/x86/kernel/process.c:717:15: warning: no previous prototype for ‘arch_randomize_brk’ [-Wmissing-prototypes]
        arch/x86/kernel/process.c:784:6: warning: no previous prototype for ‘do_arch_prctl_common’ [-Wmissing-prototypes]
        arch/x86/kernel/reboot.c:869:6: warning: no previous prototype for ‘nmi_panic_self_stop’ [-Wmissing-prototypes]
        arch/x86/kernel/smp.c:176:27: warning: no previous prototype for ‘smp_reboot_interrupt’ [-Wmissing-prototypes]
        arch/x86/kernel/smp.c:260:28: warning: no previous prototype for ‘smp_reschedule_interrupt’ [-Wmissing-prototypes]
        arch/x86/kernel/smp.c:281:28: warning: no previous prototype for ‘smp_call_function_interrupt’ [-Wmissing-prototypes]
        arch/x86/kernel/smp.c:291:28: warning: no previous prototype for ‘smp_call_function_single_interrupt’ [-Wmissing-prototypes]
        arch/x86/kernel/ftrace.c:840:6: warning: no previous prototype for ‘arch_ftrace_update_trampoline’ [-Wmissing-prototypes]
        arch/x86/kernel/ftrace.c:934:7: warning: no previous prototype for ‘arch_ftrace_trampoline_func’ [-Wmissing-prototypes]
        arch/x86/kernel/ftrace.c:946:6: warning: no previous prototype for ‘arch_ftrace_trampoline_free’ [-Wmissing-prototypes]
        arch/x86/kernel/crash.c:114:6: warning: no previous prototype for ‘crash_smp_send_stop’ [-Wmissing-prototypes]
        arch/x86/kernel/crash.c:351:5: warning: no previous prototype for ‘crash_setup_memmap_entries’ [-Wmissing-prototypes]
        arch/x86/kernel/crash.c:424:5: warning: no previous prototype for ‘crash_load_segments’ [-Wmissing-prototypes]
        arch/x86/kernel/machine_kexec_64.c:372:7: warning: no previous prototype for ‘arch_kexec_kernel_image_load’ [-Wmissing-prototypes]
        arch/x86/kernel/paravirt-spinlocks.c:12:16: warning: no previous prototype for ‘__native_queued_spin_unlock’ [-Wmissing-prototypes]
        arch/x86/kernel/paravirt-spinlocks.c:18:6: warning: no previous prototype for ‘pv_is_native_spin_unlock’ [-Wmissing-prototypes]
        arch/x86/kernel/paravirt-spinlocks.c:24:16: warning: no previous prototype for ‘__native_vcpu_is_preempted’ [-Wmissing-prototypes]
        arch/x86/kernel/paravirt-spinlocks.c:30:6: warning: no previous prototype for ‘pv_is_native_vcpu_is_preempted’ [-Wmissing-prototypes]
        arch/x86/kernel/kvm.c:258:1: warning: no previous prototype for ‘do_async_page_fault’ [-Wmissing-prototypes]
        arch/x86/kernel/jailhouse.c:200:6: warning: no previous prototype for ‘jailhouse_paravirt’ [-Wmissing-prototypes]
        arch/x86/kernel/check.c:91:13: warning: no previous prototype for ‘setup_bios_corruption_check’ [-Wmissing-prototypes]
        arch/x86/kernel/check.c:139:6: warning: no previous prototype for ‘check_for_bios_corruption’ [-Wmissing-prototypes]
        arch/x86/kernel/devicetree.c:32:13: warning: no previous prototype for ‘early_init_dt_scan_chosen_arch’ [-Wmissing-prototypes]
        arch/x86/kernel/devicetree.c:42:13: warning: no previous prototype for ‘add_dtb’ [-Wmissing-prototypes]
        arch/x86/kernel/devicetree.c:108:6: warning: no previous prototype for ‘x86_of_pci_init’ [-Wmissing-prototypes]
        arch/x86/kernel/devicetree.c:314:13: warning: no previous prototype for ‘x86_dtb_init’ [-Wmissing-prototypes]
        arch/x86/kernel/tracepoint.c:16:5: warning: no previous prototype for ‘trace_pagefault_reg’ [-Wmissing-prototypes]
        arch/x86/kernel/tracepoint.c:22:6: warning: no previous prototype for ‘trace_pagefault_unreg’ [-Wmissing-prototypes]
        arch/x86/kernel/head64.c:113:22: warning: no previous prototype for ‘__startup_64’ [-Wmissing-prototypes]
        arch/x86/kernel/head64.c:262:15: warning: no previous prototype for ‘__startup_secondary_64’ [-Wmissing-prototypes]
        arch/x86/kernel/head64.c:350:12: warning: no previous prototype for ‘early_make_pgtable’ [-Wmissing-prototypes]
      [ mingo: rewrote the changelog, fixed build errors. ]
      Signed-off-by: default avatarYi Wang <wang.yi59@zte.com.cn>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: akataria@vmware.com
      Cc: akpm@linux-foundation.org
      Cc: andy.shevchenko@gmail.com
      Cc: anton@enomsg.org
      Cc: ard.biesheuvel@linaro.org
      Cc: bhe@redhat.com
      Cc: bhelgaas@google.com
      Cc: bp@alien8.de
      Cc: ccross@android.com
      Cc: devicetree@vger.kernel.org
      Cc: douly.fnst@cn.fujitsu.com
      Cc: dwmw@amazon.co.uk
      Cc: dyoung@redhat.com
      Cc: ebiederm@xmission.com
      Cc: frank.rowand@sony.com
      Cc: frowand.list@gmail.com
      Cc: ivan.gorinov@intel.com
      Cc: jailhouse-dev@googlegroups.com
      Cc: jan.kiszka@siemens.com
      Cc: jgross@suse.com
      Cc: jroedel@suse.de
      Cc: keescook@chromium.org
      Cc: kexec@lists.infradead.org
      Cc: konrad.wilk@oracle.com
      Cc: kvm@vger.kernel.org
      Cc: linux-efi@vger.kernel.org
      Cc: linux-pci@vger.kernel.org
      Cc: luto@kernel.org
      Cc: m.mizuma@jp.fujitsu.com
      Cc: namit@vmware.com
      Cc: oleg@redhat.com
      Cc: pasha.tatashin@oracle.com
      Cc: pbonzini@redhat.com
      Cc: prarit@redhat.com
      Cc: pravin.shedge4linux@gmail.com
      Cc: rajvi.jingar@intel.com
      Cc: rkrcmar@redhat.com
      Cc: robh+dt@kernel.org
      Cc: robh@kernel.org
      Cc: rostedt@goodmis.org
      Cc: takahiro.akashi@linaro.org
      Cc: thomas.lendacky@amd.com
      Cc: tony.luck@intel.com
      Cc: up2wing@gmail.com
      Cc: virtualization@lists.linux-foundation.org
      Cc: zhe.he@windriver.com
      Cc: zhong.weidong@zte.com.cn
      Link: http://lkml.kernel.org/r/1542852249-19820-1-git-send-email-wang.yi59@zte.com.cn
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
  6. 06 May, 2018 1 commit
  7. 01 Mar, 2018 1 commit
  8. 17 Feb, 2018 1 commit
    • Prarit Bhargava's avatar
      x86/xen: Calculate __max_logical_packages on PV domains · 63e708f8
      Prarit Bhargava authored
      The kernel panics on PV domains because native_smp_cpus_done() is
      only called for HVM domains.
      Calculate __max_logical_packages for PV domains.
      Fixes: b4c0a732
       ("x86/smpboot: Fix __max_logical_packages estimate")
      Signed-off-by: default avatarPrarit Bhargava <prarit@redhat.com>
      Tested-and-reported-by: default avatarSimon Gaiser <simon@invisiblethingslab.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: x86@kernel.org
      Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
      Cc: Juergen Gross <jgross@suse.com>
      Cc: Dou Liyang <douly.fnst@cn.fujitsu.com>
      Cc: Prarit Bhargava <prarit@redhat.com>
      Cc: Kate Stewart <kstewart@linuxfoundation.org>
      Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Andi Kleen <ak@linux.intel.com>
      Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
      Cc: xen-devel@lists.xenproject.org
      Reviewed-by: default avatarBoris Ostrovsky <boris.ostrovsky@oracle.com>
      Signed-off-by: default avatarJuergen Gross <jgross@suse.com>
  9. 02 Nov, 2017 1 commit
    • Greg Kroah-Hartman's avatar
      License cleanup: add SPDX GPL-2.0 license identifier to files with no license · b2441318
      Greg Kroah-Hartman authored
      Many source files in the tree are missing licensing information, which
      makes it harder for compliance tools to determine the correct license.
      By default all files without license information are under the default
      license of the kernel, which is GPL version 2.
      Update the files which contain no license information with the 'GPL-2.0'
      SPDX license identifier.  The SPDX identifier is a legally binding
      shorthand, which can be used instead of the full boiler plate text.
      This patch is based on work done by Thomas Gleixner and Kate Stewart and
      Philippe Ombredanne.
      How this work was done:
      Patches were generated and checked against linux-4.14-rc6 for a subset of
      the use cases:
       - file had no licensing information it it.
       - file was a */uapi/* one with no licensing information in it,
       - file was a */uapi/* one with existing licensing information,
      Further patches will be generated in subsequent months to fix up cases
      where non-standard license headers were used, and references to license
      had to be inferred by heuristics based on keywords.
      The analysis to determine which SPDX License Identifier to be applied to
      a file was done in a spreadsheet of side by side results from of the
      output of two independent scanners (ScanCode & Windriver) producing SPDX
      tag:value files created by Philippe Ombredanne.  Philippe prepared the
      base worksheet, and did an initial spot review of a few 1000 files.
      The 4.13 kernel was the starting point of the analysis with 60,537 files
      assessed.  Kate Stewart did a file by file comparison of the scanner
      results in the spreadsheet to determine which SPDX license identifier(s)
      to be applied to the file. She confirmed any determination that was not
      immediately clear with lawyers working with the Linux Foundation.
      Criteria used to select files for SPDX license identifier tagging was:
       - Files considered eligible had to be source code files.
       - Make and config files were included as candidates if they contained >5
         lines of source
       - File already had some variant of a license header in it (even if <5
      All documentation files were explicitly excluded.
      The following heuristics were used to determine which SPDX license
      identifiers to apply.
       - when both scanners couldn't find any license traces, file was
         considered to have no license information in it, and the top level
         COPYING file license applied.
         For non */uapi/* files that summary was:
         SPDX license identifier                            # files
         GPL-2.0                                              11139
         and resulted in the first patch in this series.
         If that file was a */uapi/* path one, it was "GPL-2.0 WITH
         Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:
         SPDX license identifier                            # files
         GPL-2.0 WITH Linux-syscall-note                        930
         and resulted in the second patch in this series.
       - if a file had some form of licensing information in it, and was one
         of the */uapi/* ones, it was denoted with the Linux-syscall-note if
         any GPL family license was found in the file or had no licensing in
         it (per prior point).  Results summary:
         SPDX license identifier                            # files
         GPL-2.0 WITH Linux-syscall-note                       270
         GPL-2.0+ WITH Linux-syscall-note                      169
         ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
         ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
         LGPL-2.1+ WITH Linux-syscall-note                      15
         GPL-1.0+ WITH Linux-syscall-note                       14
         ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
         LGPL-2.0+ WITH Linux-syscall-note                       4
         LGPL-2.1 WITH Linux-syscall-note                        3
         ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
         ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1
         and that resulted in the third patch in this series.
       - when the two scanners agreed on the detected license(s), that became
         the concluded license(s).
       - when there was disagreement between the two scanners (one detected a
         license but the other didn't, or they both detected different
         licenses) a manual inspection of the file occurred.
       - In most cases a manual inspection of the information in the file
         resulted in a clear resolution of the license that should apply (and
         which scanner probably needed to revisit its heuristics).
       - When it was not immediately clear, the license identifier was
         confirmed with lawyers working with the Linux Foundation.
       - If there was any question as to the appropriate license identifier,
         the file was flagged for further research and to be revisited later
         in time.
      In total, over 70 hours of logged manual review was done on the
      spreadsheet to determine the SPDX license identifiers to apply to the
      source files by Kate, Philippe, Thomas and, in some cases, confirmation
      by lawyers working with the Linux Foundation.
      Kate also obtained a third independent scan of the 4.13 code base from
      FOSSology, and compared selected files where the other two scanners
      disagreed against that SPDX file, to see if there was new insights.  The
      Windriver scanner is based on an older version of FOSSology in part, so
      they are related.
      Thomas did random spot checks in about 500 files from the spreadsheets
      for the uapi headers and agreed with SPDX license identifier in the
      files he inspected. For the non-uapi files Thomas did random spot checks
      in about 15000 files.
      In initial set of patches against 4.14-rc6, 3 files were found to have
      copy/paste license identifier errors, and have been fixed to reflect the
      correct identifier.
      Additionally Philippe spent 10 hours this week doing a detailed manual
      inspection and review of the 12,461 patched files from the initial patch
      version early this week with:
       - a full scancode scan run, collecting the matched texts, detected
         license ids and scores
       - reviewing anything where there was a license detected (about 500+
         files) to ensure that the applied SPDX license was correct
       - reviewing anything where there was no detection but the patch license
         was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
         SPDX license was correct
      This produced a worksheet with 20 files needing minor correction.  This
      worksheet was then exported into 3 different .csv files for the
      different types of files to be modified.
      These .csv files were then reviewed by Greg.  Thomas wrote a script to
      parse the csv files and add the proper SPDX tag to the file, in the
      format that the file expected.  This script was further refined by Greg
      based on the output to detect more types of files automatically and to
      distinguish between header and source .c files (which need different
      comment types.)  Finally Greg ran the script using the .csv files to
      generate the patches.
      Reviewed-by: default avatarKate Stewart <kstewart@linuxfoundation.org>
      Reviewed-by: default avatarPhilippe Ombredanne <pombredanne@nexb.com>
      Reviewed-by: default avatarThomas Gleixner <tglx@linutronix.de>
      Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
  10. 14 Apr, 2017 2 commits
  11. 11 Oct, 2016 1 commit
    • Hidehiro Kawai's avatar
      x86/panic: replace smp_send_stop() with kdump friendly version in panic path · 0ee59413
      Hidehiro Kawai authored
      Daniel Walker reported problems which happens when
      crash_kexec_post_notifiers kernel option is enabled
      In that case, smp_send_stop() is called before entering kdump routines
      which assume other CPUs are still online.  As the result, for x86, kdump
      routines fail to save other CPUs' registers and disable virtualization
      To fix this problem, call a new kdump friendly function,
      crash_smp_send_stop(), instead of the smp_send_stop() when
      crash_kexec_post_notifiers is enabled.  crash_smp_send_stop() is a weak
      function, and it just call smp_send_stop().  Architecture codes should
      override it so that kdump can work appropriately.  This patch only
      provides x86-specific version.
      For Xen's PV kernel, just keep the current behavior.
      - Right solution would be to place crash_smp_send_stop() before
        __crash_kexec() invocation in all cases and remove smp_send_stop(), but
        we can't do that until all architectures implement own
      - crash_smp_send_stop()-like work is still needed by
        machine_crash_shutdown() because crash_kexec() can be called without
        entering panic()
      Fixes: f06e5153 (kernel/panic.c: add "crash_kexec_post_notifiers" option)
      Link: http://lkml.kernel.org/r/20160810080948.11028.15344.stgit@sysi4-13.yrl.intra.hitachi.co.jp
      Signed-off-by: default avatarHidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
      Reported-by: default avatarDaniel Walker <dwalker@fifo99.com>
      Cc: Dave Young <dyoung@redhat.com>
      Cc: Baoquan He <bhe@redhat.com>
      Cc: Vivek Goyal <vgoyal@redhat.com>
      Cc: Eric Biederman <ebiederm@xmission.com>
      Cc: Masami Hiramatsu <mhiramat@kernel.org>
      Cc: Daniel Walker <dwalker@fifo99.com>
      Cc: Xunlei Pang <xpang@redhat.com>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: Borislav Petkov <bp@suse.de>
      Cc: David Vrabel <david.vrabel@citrix.com>
      Cc: Toshi Kani <toshi.kani@hpe.com>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: David Daney <david.daney@cavium.com>
      Cc: Aaro Koskinen <aaro.koskinen@iki.fi>
      Cc: "Steven J. Hill" <steven.hill@cavium.com>
      Cc: Corey Minyard <cminyard@mvista.com>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
  12. 18 Aug, 2016 1 commit
    • Josh Poimboeuf's avatar
      x86/asm/head: Rename 'stack_start' -> 'initial_stack' · b32f96c7
      Josh Poimboeuf authored
      The 'stack_start' variable is similar in usage to 'initial_code' and
      'initial_gs': they're all stored in head_64.S and they're all updated by
      SMP and ACPI suspend before starting a CPU.
      Rename it to 'initial_stack' to be consistent with the others.
      Signed-off-by: default avatarJosh Poimboeuf <jpoimboe@redhat.com>
      Cc: Andy Lutomirski <luto@amacapital.net>
      Cc: Andy Lutomirski <luto@kernel.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Byungchul Park <byungchul.park@lge.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: Frederic Weisbecker <fweisbec@gmail.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Kees Cook <keescook@chromium.org>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Nilay Vaish <nilayvaish@gmail.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Steven Rostedt <rostedt@goodmis.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://lkml.kernel.org/r/87063d773a3212051b77e17b0ee427f6582a5050.1471535549.git.jpoimboe@redhat.com
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
  13. 25 Jul, 2016 1 commit
  14. 15 Jul, 2016 2 commits
    • Rafael J. Wysocki's avatar
      x86 / hibernate: Use hlt_play_dead() when resuming from hibernation · 406f992e
      Rafael J. Wysocki authored
      On Intel hardware, native_play_dead() uses mwait_play_dead() by
      default and only falls back to the other methods if that fails.
      That also happens during resume from hibernation, when the restore
      (boot) kernel runs disable_nonboot_cpus() to take all of the CPUs
      except for the boot one offline.
      However, that is problematic, because the address passed to
      __monitor() in mwait_play_dead() is likely to be written to in the
      last phase of hibernate image restoration and that causes the "dead"
      CPU to start executing instructions again.  Unfortunately, the page
      containing the address in that CPU's instruction pointer may not be
      valid any more at that point.
      First, that page may have been overwritten with image kernel memory
      contents already, so the instructions the CPU attempts to execute may
      simply be invalid.  Second, the page tables previously used by that
      CPU may have been overwritten by image kernel memory contents, so the
      address in its instruction pointer is impossible to resolve then.
      A report from Varun Koyyalagunta and investigation carried out by
      Chen Yu show that the latter sometimes happens in practice.
      To prevent it from happening, temporarily change the smp_ops.play_dead
      pointer during resume from hibernation so that it points to a special
      "play dead" routine which uses hlt_play_dead() and avoids the
      inadvertent "revivals" of "dead" CPUs this way.
      A slightly unpleasant consequence of this change is that if the
      system is hibernated with one or more CPUs offline, it will generally
      draw more power after resume than it did before hibernation, because
      the physical state entered by CPUs via hlt_play_dead() is higher-power
      than the mwait_play_dead() one in the majority of cases.  It is
      possible to work around this, but it is unclear how much of a problem
      that's going to be in practice, so the workaround will be implemented
      later if it turns out to be necessary.
      Link: https://bugzilla.kernel.org/show_bug.cgi?id=106371
      Reported-by: default avatarVarun Koyyalagunta <cpudebug@centtech.com>
      Original-by: default avatarChen Yu <yu.c.chen@intel.com>
      Tested-by: default avatarChen Yu <yu.c.chen@intel.com>
      Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
      Acked-by: default avatarIngo Molnar <mingo@kernel.org>
    • Andy Lutomirski's avatar
      x86/smp: Remove stack_smp_processor_id() · fb59831b
      Andy Lutomirski authored
      It serves no purpose -- raw_smp_processor_id() works fine.  This
      change will be needed to move thread_info off the stack.
      Signed-off-by: default avatarAndy Lutomirski <luto@kernel.org>
      Cc: Borislav Petkov <bp@alien8.de>
      Cc: Brian Gerst <brgerst@gmail.com>
      Cc: Denys Vlasenko <dvlasenk@redhat.com>
      Cc: H. Peter Anvin <hpa@zytor.com>
      Cc: Josh Poimboeuf <jpoimboe@redhat.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Link: http://lkml.kernel.org/r/a2bf4f07fbc30fb32f9f7f3f8f94ad3580823847.1468527351.git.luto@kernel.org
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
  15. 29 Mar, 2016 1 commit
  16. 30 Jan, 2016 1 commit
  17. 19 Nov, 2015 1 commit
  18. 17 Nov, 2015 1 commit
  19. 27 May, 2015 1 commit
  20. 02 Apr, 2015 1 commit
  21. 11 Mar, 2015 1 commit
    • Paul E. McKenney's avatar
      x86: Use common outgoing-CPU-notification code · 2a442c9c
      Paul E. McKenney authored
      This commit removes the open-coded CPU-offline notification with new
      common code.  Among other things, this change avoids calling scheduler
      code using RCU from an offline CPU that RCU is ignoring.  It also allows
      Xen to notice at online time that the CPU did not go offline correctly.
      Note that Xen has the surviving CPU carry out some cleanup operations,
      so if the surviving CPU times out, these cleanup operations might have
      been carried out while the outgoing CPU was still running.  It might
      therefore be unwise to bring this CPU back online, and this commit
      avoids doing so.
      Signed-off-by: default avatarBoris Ostrovsky <boris.ostrovsky@oracle.com>
      Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: <x86@kernel.org>
      Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
      Cc: David Vrabel <david.vrabel@citrix.com>
      Cc: <xen-devel@lists.xenproject.org>
  22. 10 Nov, 2014 1 commit
  23. 07 Jan, 2014 1 commit
  24. 14 Jul, 2013 1 commit
    • Paul Gortmaker's avatar
      x86: delete __cpuinit usage from all x86 files · 148f9bb8
      Paul Gortmaker authored
      The __cpuinit type of throwaway sections might have made sense
      some time ago when RAM was more constrained, but now the savings
      do not offset the cost and complications.  For example, the fix in
      commit 5e427ec2 ("x86: Fix bit corruption at CPU resume time")
      is a good example of the nasty type of bugs that can be created
      with improper use of the various __init prefixes.
      After a discussion on LKML[1] it was decided that cpuinit should go
      the way of devinit and be phased out.  Once all the users are gone,
      we can then finally remove the macros themselves from linux/init.h.
      Note that some harmless section mismatch warnings may result, since
      notify_cpu_starting() and cpu_up() are arch independent (kernel/cpu.c)
      are flagged as __cpuinit  -- so if we remove the __cpuinit from
      arch specific callers, we will also get section mismatch warnings.
      As an intermediate step, we intend to turn the linux/init.h cpuinit
      content into no-ops as early as possible, since that will get rid
      of these warnings.  In any case, they are temporary and harmless.
      This removes all the arch/x86 uses of the __cpuinit macros from
      all C files.  x86 only had the one __CPUINIT used in assembly files,
      and it wasn't paired off with a .previous or a __FINIT, so we can
      delete it directly w/o any corresponding additional change there.
      [1] https://lkml.org/lkml/2013/5/20/589
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: "H. Peter Anvin" <hpa@zytor.com>
      Cc: x86@kernel.org
      Acked-by: default avatarIngo Molnar <mingo@kernel.org>
      Acked-by: default avatarThomas Gleixner <tglx@linutronix.de>
      Acked-by: default avatarH. Peter Anvin <hpa@linux.intel.com>
      Signed-off-by: default avatarPaul Gortmaker <paul.gortmaker@windriver.com>
  25. 14 Nov, 2012 1 commit
  26. 14 Jun, 2012 1 commit
    • Vlad Zolotarov's avatar
      x86: Add read_mostly declaration/definition to variables from smp.h · 0816b0f0
      Vlad Zolotarov authored
      Add "read-mostly" qualifier to the following variables in
       - cpu_sibling_map
       - cpu_core_map
       - cpu_llc_shared_map
       - cpu_llc_id
       - cpu_number
       - x86_cpu_to_apicid
       - x86_bios_cpu_apicid
       - x86_cpu_to_logical_apicid
      As long as all the variables above are only written during the
      initialization, this change is meant to prevent the false
      sharing. More specifically, on vSMP Foundation platform
      x86_cpu_to_apicid shared the same internode_cache_line with
      frequently written lapic_events.
      From the analysis of the first 33 per_cpu variables out of 219
      (memories they describe, to be more specific) the 8 have read_mostly
      nature (tlb_vector_offset, cpu_loops_per_jiffy, xen_debug_irq, etc.)
      and 25 are frequently written (irq_stack_union, gdt_page,
      exception_stacks, idt_desc, etc.).
      Assuming that the spread of the rest of the per_cpu variables is
      similar, identifying the read mostly memories will make more sense
      in terms of long-term code maintenance comparing to identifying
      frequently written memories.
      Signed-off-by: default avatarVlad Zolotarov <vlad@scalemp.com>
      Acked-by: default avatarShai Fultheim <shai@scalemp.com>
      Cc: Shai Fultheim (Shai@ScaleMP.com) <Shai@scalemp.com>
      Cc: ido@wizery.com
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
      Link: http://lkml.kernel.org/r/1719258.EYKzE4Zbq5@vlad
      Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
  27. 05 Jun, 2012 1 commit
  28. 14 May, 2012 1 commit
  29. 26 Apr, 2012 3 commits
  30. 05 Dec, 2011 1 commit
    • Don Zickus's avatar
      x86, NMI: Add NMI IPI selftest · 99e8b9ca
      Don Zickus authored
      The previous patch modified the stop cpus path to use NMI
      instead of IRQ as the way to communicate to the other cpus to
      shutdown.  There were some concerns that various machines may
      have problems with using an NMI IPI.
      This patch creates a selftest to check if NMI is working at
      boot. The idea is to help catch any issues before the machine
      panics and we learn the hard way.
      Loosely based on the locking-selftest.c file, this separate file
      runs a couple of simple tests and reports the results.  The
      output looks like:
      Brought up 4 CPUs
      | NMI testsuite:
        remote IPI:  ok  |
         local IPI:  ok  |
      Good, all   2 testcases passed! |
      Total of 4 processors activated (21330.61 BogoMIPS).
      Signed-off-by: default avatarDon Zickus <dzickus@redhat.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Robert Richter <robert.richter@amd.com>
      Cc: seiji.aguchi@hds.com
      Cc: vgoyal@redhat.com
      Cc: mjg@redhat.com
      Cc: tony.luck@intel.com
      Cc: gong.chen@intel.com
      Cc: satoru.moriya@hds.com
      Cc: avi@redhat.com
      Cc: Andi Kleen <andi@firstfloor.org>
      Link: http://lkml.kernel.org/r/1318533267-18880-3-git-send-email-dzickus@redhat.com
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
  31. 05 Mar, 2011 1 commit
  32. 05 Feb, 2011 1 commit
  33. 28 Jan, 2011 2 commits
    • Tejun Heo's avatar
      x86: Fix build failure on X86_UP_APIC · 4e62445b
      Tejun Heo authored
      Commit 4c321ff8
       (x86: Replace cpu_2_logical_apicid[] with early
      percpu variable) and following changes introduced and used
      x86_cpu_to_logical_apicid percpu variable.  It was declared and
      defined inside CONFIG_SMP && CONFIG_X86_32 but if
      CONFIG_X86_UP_APIC is set UP configuration makes use of it and
      build fails.
      Fix it by declaring and defining it inside CONFIG_X86_LOCAL_APIC
      && CONFIG_X86_32.
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Reported-by: default avatarIngo Molnar <mingo@elte.hu>
      Cc: eric.dumazet@gmail.com
      Cc: yinghai@kernel.org
      Cc: brgerst@gmail.com
      Cc: gorcunov@gmail.com
      Cc: penberg@kernel.org
      Cc: shaohui.zheng@intel.com
      Cc: rientjes@google.com
      LKML-Reference: <20110128162248.GA25746@htj.dyndns.org>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
    • Tejun Heo's avatar
      x86: Replace cpu_2_logical_apicid[] with early percpu variable · 4c321ff8
      Tejun Heo authored
      Unlike x86_64, on x86_32, the mapping from cpu to logical apicid
      may vary depending on apic in use.  cpu_2_logical_apicid[] array
      is used for this mapping.  Replace it with early percpu variable
      x86_cpu_to_logical_apicid to make it better aligned with other
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Cc: eric.dumazet@gmail.com
      Cc: yinghai@kernel.org
      Cc: brgerst@gmail.com
      Cc: gorcunov@gmail.com
      Cc: penberg@kernel.org
      Cc: shaohui.zheng@intel.com
      Cc: rientjes@google.com
      LKML-Reference: <1295789862-25482-5-git-send-email-tj@kernel.org>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
  34. 26 Jan, 2011 1 commit
    • Yinghai Lu's avatar
      x86: Move llc_shared_map out of cpu_info · b3d7336d
      Yinghai Lu authored
      cpu_info is already with per_cpu, We can take llc_shared_map out
      of cpu_info, and declare it as per_cpu variable directly.
      So later referencing could be simple and directly instead of
      diving to find cpu_info at first.
      Also could make smp_store_cpu_info() much simple to avoid to do
      save and restore trick.
      Signed-off-by: default avatarYinghai Lu <yinghai@kernel.org>
      Cc: Hans Rosenfeld <hans.rosenfeld@amd.com>
      Cc: Alok N Kataria <akataria@vmware.com>
      Cc: Stephen Hemminger <shemminger@vyatta.com>
      Cc: Hans J. Koch <hjk@linutronix.de>
      Cc: Tejun Heo <tj@kernel.org>
      Cc: Borislav Petkov <borislav.petkov@amd.com>
      Cc: Andreas Herrmann <andreas.herrmann3@amd.com>
      Cc: Robert Richter <robert.richter@amd.com>
      Cc: Suresh Siddha <suresh.b.siddha@intel.com>
      LKML-Reference: <4D3A16E8.5020608@kernel.org>
      Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
  35. 21 Oct, 2010 1 commit
    • Alok Kataria's avatar
      x86, kexec: Make sure to stop all CPUs before exiting the kernel · 76fac077
      Alok Kataria authored
      x86 smp_ops now has a new op, stop_other_cpus which takes a parameter
      "wait" this allows the caller to specify if it wants to stop until all
      the cpus have processed the stop IPI.  This is required specifically
      for the kexec case where we should wait for all the cpus to be stopped
      before starting the new kernel.  We now wait for the cpus to stop in
      all cases except for panic/kdump where we expect things to be broken
      and we are doing our best to make things work anyway.
      This patch fixes a legitimate regression, which was introduced during
      2.6.30, by commit id 4ef702c1
      Signed-off-by: default avatarAlok N Kataria <akataria@vmware.com>
      LKML-Reference: <1286833028.1372.20.camel@ank32.eng.vmware.com>
      Cc: Eric W. Biederman <ebiederm@xmission.com>
      Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
      Cc: <stable@kernel.org> v2.6.30-36
      Signed-off-by: default avatarH. Peter Anvin <hpa@linux.intel.com>