kernel.git/arch/x86/kernel/smp.c, branch linux-4.13.y

Merge branch 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2017-05-02T03:51:12Z

Pull x86 boot updates from Ingo Molnar: "The biggest changes in this cycle were: - reworking of the e820 code: separate in-kernel and boot-ABI data structures and apply a whole range of cleanups to the kernel side. No change in functionality. - enable KASLR by default: it's used by all major distros and it's out of the experimental stage as well. - ... misc fixes and cleanups" * 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (63 commits) x86/KASLR: Fix kexec kernel boot crash when KASLR randomization fails x86/reboot: Turn off KVM when halting a CPU x86/boot: Fix BSS corruption/overwrite bug in early x86 kernel startup x86: Enable KASLR by default boot/param: Move next_arg() function to lib/cmdline.c for later reuse x86/boot: Fix Sparse warning by including required header file x86/boot/64: Rename start_cpu() x86/xen: Update e820 table handling to the new core x86 E820 code x86/boot: Fix pr_debug() API braindamage xen, x86/headers: Add dependency to x86/boot/e820: Simplify e820__update_table() x86/boot/e820: Separate the E820 ABI structures from the in-kernel structures x86/boot/e820: Fix and clean up e820_type switch() statements x86/boot/e820: Rename the remaining E820 APIs to the e820__*() prefix x86/boot/e820: Remove unnecessary #include's x86/boot/e820: Rename e820_mark_nosave_regions() to e820__register_nosave_regions() x86/boot/e820: Rename e820_reserve_resources*() to e820__reserve_resources*() x86/boot/e820: Use bool in query APIs x86/boot/e820: Document e820__reserve_setup_data() x86/boot/e820: Clean up __e820__update_table() et al ...

sched/x86: Update reschedule warning text

2017-04-20T08:14:30Z

Modify the reschedule warning to output the offline CPU number and use a better debug message. Signed-off-by: Prarit Bhargava Cc: Andrew Morton Cc: Daniel Bristot de Oliveira Cc: Hidehiro Kawai Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Steven Rostedt (VMware) Cc: Thomas Gleixner Cc: Wanpeng Li Link: http://lkml.kernel.org/r/1492518305-3808-1-git-send-email-prarit@redhat.com [ Tweaked the warning message. ] Signed-off-by: Ingo Molnar

x86/reboot: Turn off KVM when halting a CPU

2017-04-20T08:06:57Z

A CPU in VMX root mode will ignore INIT signals and will fail to bring up the APs after reboot. Therefore, on a panic we disable VMX on all CPUs before rebooting or triggering kdump. Do this when halting the machine as well, in case a firmware-level reboot does not perform a cold reset for all processors. Without doing this, rebooting the host may hang. Signed-off-by: Tiantian Feng Signed-off-by: Xishi Qiu [ Rewritten commit message. ] Signed-off-by: Paolo Bonzini Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: kvm@vger.kernel.org Link: http://lkml.kernel.org/r/20170419161839.30550-1-pbonzini@redhat.com Signed-off-by: Ingo Molnar

x86/irq, trace: Add __irq_entry annotation to x86's platform IRQ handlers

2017-01-05T07:58:49Z

This patch adds the __irq_entry annotation to the default x86 platform IRQ handlers. ftrace's function_graph tracer uses the __irq_entry annotation to notify the entry and return of IRQ handlers. For example, before the patch: 354549.667252 | 3) d..1 | default_idle_call() { 354549.667252 | 3) d..1 | arch_cpu_idle() { 354549.667253 | 3) d..1 | default_idle() { 354549.696886 | 3) d..1 | smp_trace_reschedule_interrupt() { 354549.696886 | 3) d..1 | irq_enter() { 354549.696886 | 3) d..1 | rcu_irq_enter() { After the patch: 366416.254476 | 3) d..1 | arch_cpu_idle() { 366416.254476 | 3) d..1 | default_idle() { 366416.261566 | 3) d..1 ==========> | 366416.261566 | 3) d..1 | smp_trace_reschedule_interrupt() { 366416.261566 | 3) d..1 | irq_enter() { 366416.261566 | 3) d..1 | rcu_irq_enter() { KASAN also uses this annotation. The smp_apic_timer_interrupt() was already annotated. Signed-off-by: Daniel Bristot de Oliveira Acked-by: Steven Rostedt (VMware) Cc: Aaron Lu Cc: Andrew Morton Cc: Baoquan He Cc: Borislav Petkov Cc: Claudio Fontana Cc: Denys Vlasenko Cc: Dou Liyang Cc: Gu Zheng Cc: Hidehiro Kawai Cc: Linus Torvalds Cc: Nicolai Stange Cc: Peter Zijlstra (Intel) Cc: Steven Rostedt Cc: Thomas Gleixner Cc: Tony Luck Cc: Wanpeng Li Cc: linux-edac@vger.kernel.org Link: http://lkml.kernel.org/r/059fdf437c2f0c09b13c18c8fe4e69999d3ffe69.1483528431.git.bristot@redhat.com Signed-off-by: Ingo Molnar

x86/apic: Prevent tracing on apic_msr_write_eoi()

2016-11-09T21:03:14Z

The following RCU lockdep warning led to adding irq_enter()/irq_exit() into smp_reschedule_interrupt(): RCU used illegally from idle CPU! rcu_scheduler_active = 1, debug_locks = 0 RCU used illegally from extended quiescent state! no locks held by swapper/1/0. do_trace_write_msr native_write_msr native_apic_msr_eoi_write smp_reschedule_interrupt reschedule_interrupt As Peterz pointed out: | So now we're making a very frequent interrupt slower because of debug | code. | | The thing is, many many smp_reschedule_interrupt() invocations don't | actually execute anything much at all and are only sent to tickle the | return to user path (which does the actual preemption). | | Having to do the whole irq_enter/irq_exit dance just for this unlikely | debug case totally blows. Use the wrmsr_notrace() variant in native_apic_msr_write_eoi, annotate the kvm variant with notrace and add a native_apic_eoi callback to the apic structure so KVM guests are covered as well. This allows to revert the irq_enter/irq_exit dance in smp_reschedule_interrupt(). Suggested-by: Peter Zijlstra Suggested-by: Paolo Bonzini Signed-off-by: Wanpeng Li Acked-by: Paolo Bonzini Cc: kvm@vger.kernel.org Cc: Mike Galbraith Cc: Borislav Petkov Link: http://lkml.kernel.org/r/1478488420-5982-3-git-send-email-wanpeng.li@hotmail.com Signed-off-by: Thomas Gleixner

Merge tag 'v4.9-rc1' into x86/urgent, to pick up updates

2016-10-16T09:31:39Z

Signed-off-by: Ingo Molnar

x86/smp: Add irq_enter/exit() in smp_reschedule_interrupt()

2016-10-14T12:14:20Z

=============================== [ INFO: suspicious RCU usage. ] 4.8.0+ #24 Not tainted ------------------------------- ./arch/x86/include/asm/msr-trace.h:47 suspicious rcu_dereference_check() usage! other info that might help us debug this: RCU used illegally from idle CPU! rcu_scheduler_active = 1, debug_locks = 0 RCU used illegally from extended quiescent state! no locks held by swapper/1/0. [] do_trace_write_msr+0x135/0x140 [] native_write_msr+0x20/0x30 [] native_apic_msr_eoi_write+0x1d/0x30 [] smp_reschedule_interrupt+0x1d/0x30 [] reschedule_interrupt+0x96/0xa0 Reschedule interrupt may be called in cpu idle state. This causes lockdep check warning above. Add irq_enter/exit() in smp_reschedule_interrupt(), irq_enter() tells the RCU subsystems to end the extended quiescent state, so the following trace call in ack_APIC_irq() works correctly. Signed-off-by: Wanpeng Li Cc: Peter Zijlstra Cc: Mike Galbraith Link: http://lkml.kernel.org/r/1476409733-5133-1-git-send-email-wanpeng.li@hotmail.com Signed-off-by: Thomas Gleixner

x86/panic: replace smp_send_stop() with kdump friendly version in panic path

2016-10-11T22:06:32Z

Daniel Walker reported problems which happens when crash_kexec_post_notifiers kernel option is enabled (https://lkml.org/lkml/2015/6/24/44). 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 extensions. 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. NOTES: - 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() - crash_smp_send_stop()-like work is still needed by machine_crash_shutdown() because crash_kexec() can be called without entering panic() Fixes: f06e5153f4ae (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: Hidehiro Kawai Reported-by: Daniel Walker Cc: Dave Young Cc: Baoquan He Cc: Vivek Goyal Cc: Eric Biederman Cc: Masami Hiramatsu Cc: Daniel Walker Cc: Xunlei Pang Cc: Thomas Gleixner Cc: Ingo Molnar Cc: "H. Peter Anvin" Cc: Borislav Petkov Cc: David Vrabel Cc: Toshi Kani Cc: Ralf Baechle Cc: David Daney Cc: Aaro Koskinen Cc: "Steven J. Hill" Cc: Corey Minyard Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

x86/smp: Remove single IPI wrapper

2015-11-05T12:07:54Z

All APIC implementation have send_IPI now. Remove the conditional in the calling code. Signed-off-by: Thomas Gleixner Reviewed-by: Ingo Molnar Cc: Linus Torvalds Cc: Borislav Petkov Cc: Peter Zijlstra Cc: Mike Travis Cc: Daniel J Blueman Link: http://lkml.kernel.org/r/20151104220849.807817097@linutronix.de

x86/apic: Add a single-target IPI function to the apic

2015-11-05T12:07:51Z

We still fall back on the "send mask" versions if an apic definition doesn't have the single-target version, but at least this allows the (trivial) case for the common clustered x2apic case. Signed-off-by: Linus Torvalds Reviewed-by: Ingo Molnar Cc: Borislav Petkov Cc: Peter Zijlstra Cc: Mike Travis Cc: Daniel J Blueman Link: http://lkml.kernel.org/r/20151104220848.737120838@linutronix.de Signed-off-by: Thomas Gleixner