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2015-07-15genirq: Revert sparse irq locking around __cpu_up() and move it to x86 for nowThomas Gleixner
Boris reported that the sparse_irq protection around __cpu_up() in the generic code causes a regression on Xen. Xen allocates interrupts and some more in the xen_cpu_up() function, so it deadlocks on the sparse_irq_lock. There is no simple fix for this and we really should have the protection for all architectures, but for now the only solution is to move it to x86 where actual wreckage due to the lack of protection has been observed. Reported-and-tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Fixes: a89941816726 'hotplug: Prevent alloc/free of irq descriptors during cpu up/down' Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: xiao jin <jin.xiao@intel.com> Cc: Joerg Roedel <jroedel@suse.de> Cc: Borislav Petkov <bp@suse.de> Cc: Yanmin Zhang <yanmin_zhang@linux.intel.com> Cc: xen-devel <xen-devel@lists.xenproject.org>
2015-07-07x86/irq: Plug irq vector hotplug raceThomas Gleixner
Jin debugged a nasty cpu hotplug race which results in leaking a irq vector on the newly hotplugged cpu. cpu N cpu M native_cpu_up device_shutdown do_boot_cpu free_msi_irqs start_secondary arch_teardown_msi_irqs smp_callin default_teardown_msi_irqs setup_vector_irq arch_teardown_msi_irq __setup_vector_irq native_teardown_msi_irq lock(vector_lock) destroy_irq install vectors unlock(vector_lock) lock(vector_lock) ---> __clear_irq_vector unlock(vector_lock) lock(vector_lock) set_cpu_online unlock(vector_lock) This leaves the irq vector(s) which are torn down on CPU M stale in the vector array of CPU N, because CPU M does not see CPU N online yet. There is a similar issue with concurrent newly setup interrupts. The alloc/free protection of irq descriptors does not prevent the above race, because it merily prevents interrupt descriptors from going away or changing concurrently. Prevent this by moving the call to setup_vector_irq() into the vector_lock held region which protects set_cpu_online(): cpu N cpu M native_cpu_up device_shutdown do_boot_cpu free_msi_irqs start_secondary arch_teardown_msi_irqs smp_callin default_teardown_msi_irqs lock(vector_lock) arch_teardown_msi_irq setup_vector_irq() __setup_vector_irq native_teardown_msi_irq install vectors destroy_irq set_cpu_online unlock(vector_lock) lock(vector_lock) __clear_irq_vector unlock(vector_lock) So cpu M either sees the cpu N online before clearing the vector or cpu N installs the vectors after cpu M has cleared it. Reported-by: xiao jin <jin.xiao@intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Joerg Roedel <jroedel@suse.de> Cc: Borislav Petkov <bp@suse.de> Cc: Yanmin Zhang <yanmin_zhang@linux.intel.com> Link: http://lkml.kernel.org/r/20150705171102.141898931@linutronix.de
2015-07-06x86/espfix: Init espfix on the boot CPU sideZhu Guihua
As we alloc pages with GFP_KERNEL in init_espfix_ap() which is called before we enable local irqs, so the lockdep sub-system would (correctly) trigger a warning about the potentially blocking API. So we allocate them on the boot CPU side when the secondary CPU is brought up by the boot CPU, and hand them over to the secondary CPU. And we use alloc_pages_node() with the secondary CPU's node, to make sure the espfix stack is NUMA-local to the CPU that is going to use it. Signed-off-by: Zhu Guihua <zhugh.fnst@cn.fujitsu.com> Cc: <bp@alien8.de> Cc: <luto@amacapital.net> Cc: <luto@kernel.org> 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/c97add2670e9abebb90095369f0cfc172373ac94.1435824469.git.zhugh.fnst@cn.fujitsu.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-07-06x86/espfix: Add 'cpu' parameter to init_espfix_ap()Zhu Guihua
Add a CPU index parameter to init_espfix_ap(), so that the parameter could be propagated to the function for espfix page allocation. Signed-off-by: Zhu Guihua <zhugh.fnst@cn.fujitsu.com> Cc: <bp@alien8.de> Cc: <luto@amacapital.net> Cc: <luto@kernel.org> 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/cde3fcf1b3211f3f03feb1a995bce3fee850f0fc.1435824469.git.zhugh.fnst@cn.fujitsu.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-06-22Merge branch 'x86-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 core updates from Ingo Molnar: "There were so many changes in the x86/asm, x86/apic and x86/mm topics in this cycle that the topical separation of -tip broke down somewhat - so the result is a more traditional architecture pull request, collected into the 'x86/core' topic. The topics were still maintained separately as far as possible, so bisectability and conceptual separation should still be pretty good - but there were a handful of merge points to avoid excessive dependencies (and conflicts) that would have been poorly tested in the end. The next cycle will hopefully be much more quiet (or at least will have fewer dependencies). The main changes in this cycle were: * x86/apic changes, with related IRQ core changes: (Jiang Liu, Thomas Gleixner) - This is the second and most intrusive part of changes to the x86 interrupt handling - full conversion to hierarchical interrupt domains: [IOAPIC domain] ----- | [MSI domain] --------[Remapping domain] ----- [ Vector domain ] | (optional) | [HPET MSI domain] ----- | | [DMAR domain] ----------------------------- | [Legacy domain] ----------------------------- This now reflects the actual hardware and allowed us to distangle the domain specific code from the underlying parent domain, which can be optional in the case of interrupt remapping. It's a clear separation of functionality and removes quite some duct tape constructs which plugged the remap code between ioapic/msi/hpet and the vector management. - Intel IOMMU IRQ remapping enhancements, to allow direct interrupt injection into guests (Feng Wu) * x86/asm changes: - Tons of cleanups and small speedups, micro-optimizations. This is in preparation to move a good chunk of the low level entry code from assembly to C code (Denys Vlasenko, Andy Lutomirski, Brian Gerst) - Moved all system entry related code to a new home under arch/x86/entry/ (Ingo Molnar) - Removal of the fragile and ugly CFI dwarf debuginfo annotations. Conversion to C will reintroduce many of them - but meanwhile they are only getting in the way, and the upstream kernel does not rely on them (Ingo Molnar) - NOP handling refinements. (Borislav Petkov) * x86/mm changes: - Big PAT and MTRR rework: making the code more robust and preparing to phase out exposing direct MTRR interfaces to drivers - in favor of using PAT driven interfaces (Toshi Kani, Luis R Rodriguez, Borislav Petkov) - New ioremap_wt()/set_memory_wt() interfaces to support Write-Through cached memory mappings. This is especially important for good performance on NVDIMM hardware (Toshi Kani) * x86/ras changes: - Add support for deferred errors on AMD (Aravind Gopalakrishnan) This is an important RAS feature which adds hardware support for poisoned data. That means roughly that the hardware marks data which it has detected as corrupted but wasn't able to correct, as poisoned data and raises an APIC interrupt to signal that in the form of a deferred error. It is the OS's responsibility then to take proper recovery action and thus prolonge system lifetime as far as possible. - Add support for Intel "Local MCE"s: upcoming CPUs will support CPU-local MCE interrupts, as opposed to the traditional system- wide broadcasted MCE interrupts (Ashok Raj) - Misc cleanups (Borislav Petkov) * x86/platform changes: - Intel Atom SoC updates ... and lots of other cleanups, fixlets and other changes - see the shortlog and the Git log for details" * 'x86-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (222 commits) x86/hpet: Use proper hpet device number for MSI allocation x86/hpet: Check for irq==0 when allocating hpet MSI interrupts x86/mm/pat, drivers/infiniband/ipath: Use arch_phys_wc_add() and require PAT disabled x86/mm/pat, drivers/media/ivtv: Use arch_phys_wc_add() and require PAT disabled x86/platform/intel/baytrail: Add comments about why we disabled HPET on Baytrail genirq: Prevent crash in irq_move_irq() genirq: Enhance irq_data_to_desc() to support hierarchy irqdomain iommu, x86: Properly handle posted interrupts for IOMMU hotplug iommu, x86: Provide irq_remapping_cap() interface iommu, x86: Setup Posted-Interrupts capability for Intel iommu iommu, x86: Add cap_pi_support() to detect VT-d PI capability iommu, x86: Avoid migrating VT-d posted interrupts iommu, x86: Save the mode (posted or remapped) of an IRTE iommu, x86: Implement irq_set_vcpu_affinity for intel_ir_chip iommu: dmar: Provide helper to copy shared irte fields iommu: dmar: Extend struct irte for VT-d Posted-Interrupts iommu: Add new member capability to struct irq_remap_ops x86/asm/entry/64: Disentangle error_entry/exit gsbase/ebx/usermode code x86/asm/entry/32: Shorten __audit_syscall_entry() args preparation x86/asm/entry/32: Explain reloading of registers after __audit_syscall_entry() ...
2015-06-22Merge branch 'x86-fpu-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 FPU updates from Ingo Molnar: "This tree contains two main changes: - The big FPU code rewrite: wide reaching cleanups and reorganization that pulls all the FPU code together into a clean base in arch/x86/fpu/. The resulting code is leaner and faster, and much easier to understand. This enables future work to further simplify the FPU code (such as removing lazy FPU restores). By its nature these changes have a substantial regression risk: FPU code related bugs are long lived, because races are often subtle and bugs mask as user-space failures that are difficult to track back to kernel side backs. I'm aware of no unfixed (or even suspected) FPU related regression so far. - MPX support rework/fixes. As this is still not a released CPU feature, there were some buglets in the code - should be much more robust now (Dave Hansen)" * 'x86-fpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (250 commits) x86/fpu: Fix double-increment in setup_xstate_features() x86/mpx: Allow 32-bit binaries on 64-bit kernels again x86/mpx: Do not count MPX VMAs as neighbors when unmapping x86/mpx: Rewrite the unmap code x86/mpx: Support 32-bit binaries on 64-bit kernels x86/mpx: Use 32-bit-only cmpxchg() for 32-bit apps x86/mpx: Introduce new 'directory entry' to 'addr' helper function x86/mpx: Add temporary variable to reduce masking x86: Make is_64bit_mm() widely available x86/mpx: Trace allocation of new bounds tables x86/mpx: Trace the attempts to find bounds tables x86/mpx: Trace entry to bounds exception paths x86/mpx: Trace #BR exceptions x86/mpx: Introduce a boot-time disable flag x86/mpx: Restrict the mmap() size check to bounds tables x86/mpx: Remove redundant MPX_BNDCFG_ADDR_MASK x86/mpx: Clean up the code by not passing a task pointer around when unnecessary x86/mpx: Use the new get_xsave_field_ptr()API x86/fpu/xstate: Wrap get_xsave_addr() to make it safer x86/fpu/xstate: Fix up bad get_xsave_addr() assumptions ...
2015-05-27x86: Replace cpu_**_mask() with topology_**_cpumask()Bartosz Golaszewski
The former duplicate the functionalities of the latter but are neither documented nor arch-independent. Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Cc: Benoit Cousson <bcousson@baylibre.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Guenter Roeck <linux@roeck-us.net> Cc: Jean Delvare <jdelvare@suse.de> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Drokin <oleg.drokin@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J. Wysocki <rjw@rjwysocki.net> Cc: Russell King <linux@arm.linux.org.uk> Cc: Viresh Kumar <viresh.kumar@linaro.org> Link: http://lkml.kernel.org/r/1432645896-12588-9-git-send-email-bgolaszewski@baylibre.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19x86/fpu: Rename fpu-internal.h to fpu/internal.hIngo Molnar
This unifies all the FPU related header files under a unified, hiearchical naming scheme: - asm/fpu/types.h: FPU related data types, needed for 'struct task_struct', widely included in almost all kernel code, and hence kept as small as possible. - asm/fpu/api.h: FPU related 'public' methods exported to other subsystems. - asm/fpu/internal.h: FPU subsystem internal methods - asm/fpu/xsave.h: XSAVE support internal methods (Also standardize the header guard in asm/fpu/internal.h.) Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-19x86/fpu: Fix header file dependencies of fpu-internal.hIngo Molnar
Fix a minor header file dependency bug in asm/fpu-internal.h: it relies on i387.h but does not include it. All users of fpu-internal.h included it explicitly. Also remove unnecessary includes, to reduce compilation time. This also makes it easier to use it as a standalone header file for FPU internals, such as an upcoming C module in arch/x86/kernel/fpu/. Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-18x86/smp/boot: Fix legacy SMP bootup slow-boot bugIngo Molnar
So while testing kernels using tools/kvm/ (kvmtool) I noticed that it booted super slow: [ 0.142991] Performance Events: no PMU driver, software events only. [ 0.149265] x86: Booting SMP configuration: [ 0.149765] .... node #0, CPUs: #1 [ 0.148304] kvm-clock: cpu 1, msr 2:1bfe9041, secondary cpu clock [ 10.158813] KVM setup async PF for cpu 1 [ 10.159000] #2 [ 10.159000] kvm-stealtime: cpu 1, msr 211a4d400 [ 10.158829] kvm-clock: cpu 2, msr 2:1bfe9081, secondary cpu clock [ 20.167805] KVM setup async PF for cpu 2 [ 20.168000] #3 [ 20.168000] kvm-stealtime: cpu 2, msr 211a8d400 [ 20.167818] kvm-clock: cpu 3, msr 2:1bfe90c1, secondary cpu clock [ 30.176902] KVM setup async PF for cpu 3 [ 30.177000] #4 [ 30.177000] kvm-stealtime: cpu 3, msr 211acd400 One CPU booted up per 10 seconds. With 120 CPUs that takes a while. Bisection pinpointed this commit: 853b160aaafb ("Revert f5d6a52f5111 ("x86/smpboot: Skip delays during SMP initialization similar to Xen")") But that commit just restores previous behavior, so it cannot cause the problem. After some head scratching it turns out that these two commits: 1a744cb356c5 ("x86/smp/boot: Remove 10ms delay from cpu_up() on modern processors") d68921f9bd14 ("x86/smp/boot: Add cmdline "cpu_init_udelay=N" to specify cpu_up() delay") added the following code to smpboot.c: - mdelay(10); + mdelay(init_udelay); Note the mismatch in the units: the delay is called 'udelay' and is set to microseconds - while the function used here is actually 'mdelay', which counts in milliseconds ... So the delay for legacy systems is off by a factor of 1,000, so instead of 10 msecs we waited for 10 seconds ... The reason bisection pointed to 853b160aaafb was that 853b160aaafb removed a (broken) boot-time speedup patch, which masked the factor 1,000 bug. Fix it by using udelay(). This fixes my bootup problems. Cc: Len Brown <len.brown@intel.com> Cc: Alan Cox <alan@linux.intel.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jan H. Schönherr <jschoenh@amazon.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-13Revert f5d6a52f5111 ("x86/smpboot: Skip delays during SMP initialization ↵Ingo Molnar
similar to Xen") Huang Ying reported x86 boot hangs due to this commit. Turns out that the change, despite its changelog, does more than just change timeouts: it also changes the way we assert/deassert INIT via the APIC_DM_INIT IPI, in the x2apic case it skips the deassert step. This is historically fragile code and the patch did not improve it, so revert these changes. This commit: 1a744cb356c5 ("x86/smp/boot: Remove 10ms delay from cpu_up() on modern processors") independently removes the worst of the delays (the 10 msec delay). The remaining delays can be addressed one by one, combined with careful testing. Reported-by: Huang Ying <ying.huang@intel.com> Cc: Anthony Liguori <aliguori@amazon.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Gang Wei <gang.wei@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jan H. Schönherr <jschoenh@amazon.de> Cc: Len Brown <len.brown@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tim Deegan <tim@xen.org> Link: http://lkml.kernel.org/r/1430732554-7294-1-git-send-email-jschoenh@amazon.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-12x86/smp/boot: Remove 10ms delay from cpu_up() on modern processorsLen Brown
Modern processor familes do not require the 10ms delay in cpu_up() to de-assert INIT. This speeds up boot and resume by 10ms per (application) processor. Signed-off-by: Len Brown <len.brown@intel.com> Cc: Alan Cox <alan@linux.intel.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jan H. Schönherr <jschoenh@amazon.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/021ce30c88f216ad39686646421194dc25671e55.1431379433.git.len.brown@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-12x86/smp/boot: Add cmdline "cpu_init_udelay=N" to specify cpu_up() delayLen Brown
No change to default behavior. Replace the hard-coded mdelay(10) in cpu_up() with a variable udelay, that is set to a defined default -- rather than a magic number. Add a boot-time override, "cpu_init_udelay=N" Signed-off-by: Len Brown <len.brown@intel.com> Cc: Alan Cox <alan@linux.intel.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jan H. Schönherr <jschoenh@amazon.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/2fe8e6c798e8def271122f62df9bbf58dc283e2a.1431379433.git.len.brown@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-11Merge branch 'x86/asm' into x86/apic, to resolve a conflictIngo Molnar
Conflicts: arch/x86/kernel/apic/io_apic.c arch/x86/kernel/apic/vector.c Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-08x86/entry: Remove unused 'kernel_stack' per-cpu variableDenys Vlasenko
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Borislav Petkov <bp@alien8.de> 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: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Drewry <wad@chromium.org> Link: http://lkml.kernel.org/r/1429889495-27850-2-git-send-email-dvlasenk@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-05-06x86/smpboot: Skip delays during SMP initialization similar to XenJan H. Schönherr
Remove the per-CPU delays during SMP initialization, which seems to be possible on newer architectures with an x2APIC. Xen does this since 2011. In fact, this commit is basically a combination of the following Xen commits. The first removes the delays, the second fixes an issue with the removal: commit 68fce206f6dba9981e8322269db49692c95ce250 Author: Tim Deegan <Tim.Deegan@citrix.com> Date: Tue Jul 19 14:13:01 2011 +0100 x86: Remove timeouts from INIT-SIPI-SIPI sequence when using x2apic. Some of the timeouts are pointless since they're waiting for the ICR to ack the IPI delivery and that doesn't happen on x2apic. The others should be benign (and are suggested in the SDM) but removing them makes AP bringup much more reliable on some test boxes. Signed-off-by: Tim Deegan <Tim.Deegan@citrix.com> commit f12ee533150761df5a7099c83f2a5fa6c07d1187 Author: Gang Wei <gang.wei@intel.com> Date: Thu Dec 29 10:07:54 2011 +0000 X86: Add a delay between INIT & SIPIs for tboot AP bring-up in X2APIC case Without this delay, Xen could not bring APs up while working with TXT/tboot, because tboot needs some time in APs to handle INIT before becoming ready for receiving SIPIs (this delay was removed as part of c/s 23724 by Tim Deegan). Signed-off-by: Gang Wei <gang.wei@intel.com> Acked-by: Keir Fraser <keir@xen.org> Acked-by: Tim Deegan <tim@xen.org> Committed-by: Tim Deegan <tim@xen.org> Signed-off-by: Jan H. Schönherr <jschoenh@amazon.de> Cc: Anthony Liguori <aliguori@amazon.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Gang Wei <gang.wei@intel.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Len Brown <len.brown@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tim Deegan <tim@xen.org> Link: http://lkml.kernel.org/r/1430732554-7294-1-git-send-email-jschoenh@amazon.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-14Merge branch 'core-rcu-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull RCU changes from Ingo Molnar: "The main changes in this cycle were: - changes permitting use of call_rcu() and friends very early in boot, for example, before rcu_init() is invoked. - add in-kernel API to enable and disable expediting of normal RCU grace periods. - improve RCU's handling of (hotplug-) outgoing CPUs. - NO_HZ_FULL_SYSIDLE fixes. - tiny-RCU updates to make it more tiny. - documentation updates. - miscellaneous fixes" * 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (58 commits) cpu: Provide smpboot_thread_init() on !CONFIG_SMP kernels as well cpu: Defer smpboot kthread unparking until CPU known to scheduler rcu: Associate quiescent-state reports with grace period rcu: Yet another fix for preemption and CPU hotplug rcu: Add diagnostics to grace-period cleanup rcutorture: Default to grace-period-initialization delays rcu: Handle outgoing CPUs on exit from idle loop cpu: Make CPU-offline idle-loop transition point more precise rcu: Eliminate ->onoff_mutex from rcu_node structure rcu: Process offlining and onlining only at grace-period start rcu: Move rcu_report_unblock_qs_rnp() to common code rcu: Rework preemptible expedited bitmask handling rcu: Remove event tracing from rcu_cpu_notify(), used by offline CPUs rcutorture: Enable slow grace-period initializations rcu: Provide diagnostic option to slow down grace-period initialization rcu: Detect stalls caused by failure to propagate up rcu_node tree rcu: Eliminate empty HOTPLUG_CPU ifdef rcu: Simplify sync_rcu_preempt_exp_init() rcu: Put all orphan-callback-related code under same comment rcu: Consolidate offline-CPU callback initialization ...
2015-04-13Merge branch 'x86-asm-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 asm changes from Ingo Molnar: "There were lots of changes in this development cycle: - over 100 separate cleanups, restructuring changes, speedups and fixes in the x86 system call, irq, trap and other entry code, part of a heroic effort to deobfuscate a decade old spaghetti asm code and its C code dependencies (Denys Vlasenko, Andy Lutomirski) - alternatives code fixes and enhancements (Borislav Petkov) - simplifications and cleanups to the compat code (Brian Gerst) - signal handling fixes and new x86 testcases (Andy Lutomirski) - various other fixes and cleanups By their nature many of these changes are risky - we tried to test them well on many different x86 systems (there are no known regressions), and they are split up finely to help bisection - but there's still a fair bit of residual risk left so caveat emptor" * 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (148 commits) perf/x86/64: Report regs_user->ax too in get_regs_user() perf/x86/64: Simplify regs_user->abi setting code in get_regs_user() perf/x86/64: Do report user_regs->cx while we are in syscall, in get_regs_user() perf/x86/64: Do not guess user_regs->cs, ss, sp in get_regs_user() x86/asm/entry/32: Tidy up JNZ instructions after TESTs x86/asm/entry/64: Reduce padding in execve stubs x86/asm/entry/64: Remove GET_THREAD_INFO() in ret_from_fork x86/asm/entry/64: Simplify jumps in ret_from_fork x86/asm/entry/64: Remove a redundant jump x86/asm/entry/64: Optimize [v]fork/clone stubs x86/asm/entry: Zero EXTRA_REGS for stub32_execve() too x86/asm/entry/64: Move stub_x32_execvecloser() to stub_execveat() x86/asm/entry/64: Use common code for rt_sigreturn() epilogue x86/asm/entry/64: Add forgotten CFI annotation x86/asm/entry/irq: Simplify interrupt dispatch table (IDT) layout x86/asm/entry/64: Move opportunistic sysret code to syscall code path x86, selftests: Add sigreturn selftest x86/alternatives: Guard NOPs optimization x86/asm/entry: Clear EXTRA_REGS for all executable formats x86/signal: Remove pax argument from restore_sigcontext ...
2015-04-02x86/cpu: Factor out common CPU initialization code, fix 32-bit Xen PV guestsBoris Ostrovsky
Some of x86 bare-metal and Xen CPU initialization code is common between the two and therefore can be factored out to avoid code duplication. As a side effect, doing so will also extend the fix provided by commit a7fcf28d431e ("x86/asm/entry: Replace this_cpu_sp0() with current_top_of_stack() to x86_32") to 32-bit Xen PV guests. Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Cc: Andy Lutomirski <luto@amacapital.net> 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: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: konrad.wilk@oracle.com Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/1427897534-5086-1-git-send-email-boris.ostrovsky@oracle.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-04-01x86/apic: Remove verify_local_APIC()Bandan Das
__verify_local_APIC() is detritus from the early APIC days. Its return value isn't used anywhere and the information it prints when debug is enabled is already part of APIC initialization messages printed to syslog. Off with it! Signed-off-by: Bandan Das <bsd@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/jpgy4mcsxsq.fsf@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-24x86/asm/entry: Get rid of KERNEL_STACK_OFFSETDenys Vlasenko
PER_CPU_VAR(kernel_stack) was set up in a way where it points five stack slots below the top of stack. Presumably, it was done to avoid one "sub $5*8,%rsp" in syscall/sysenter code paths, where iret frame needs to be created by hand. Ironically, none of them benefits from this optimization, since all of them need to allocate additional data on stack (struct pt_regs), so they still have to perform subtraction. This patch eliminates KERNEL_STACK_OFFSET. PER_CPU_VAR(kernel_stack) now points directly to top of stack. pt_regs allocations are adjusted to allocate iret frame as well. Hopefully we can merge it later with 32-bit specific PER_CPU_VAR(cpu_current_top_of_stack) variable... Net result in generated code is that constants in several insns are changed. This change is necessary for changing struct pt_regs creation in SYSCALL64 code path from MOV to PUSH instructions. Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com> Acked-by: Borislav Petkov <bp@suse.de> Acked-by: Andy Lutomirski <luto@kernel.org> Cc: Alexei Starovoitov <ast@plumgrid.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> 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: Oleg Nesterov <oleg@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Will Drewry <wad@chromium.org> Link: http://lkml.kernel.org/r/1426785469-15125-2-git-send-email-dvlasenk@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-03-11x86: Use common outgoing-CPU-notification codePaul E. McKenney
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: Boris Ostrovsky <boris.ostrovsky@oracle.com> Signed-off-by: Paul 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>
2015-03-07x86/asm/entry: Replace this_cpu_sp0() with current_top_of_stack() and fix it ↵Andy Lutomirski
on x86_32 I broke 32-bit kernels. The implementation of sp0 was correct as far as I can tell, but sp0 was much weirder on x86_32 than I realized. It has the following issues: - Init's sp0 is inconsistent with everything else's: non-init tasks are offset by 8 bytes. (I have no idea why, and the comment is unhelpful.) - vm86 does crazy things to sp0. Fix it up by replacing this_cpu_sp0() with current_top_of_stack() and using a new percpu variable to track the top of the stack on x86_32. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: 75182b1632a8 ("x86/asm/entry: Switch all C consumers of kernel_stack to this_cpu_sp0()") Link: http://lkml.kernel.org/r/d09dbe270883433776e0cbee3c7079433349e96d.1425692936.git.luto@amacapital.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-01-22x86: Consolidate boot cpu timer setupThomas Gleixner
Now that the APIC bringup is consolidated we can move the setup call for the percpu clock event device to apic_bsp_setup(). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Borislav Petkov <bp@alien8.de> Link: http://lkml.kernel.org/r/20150115211704.162567839@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-01-22x86/apic: Reuse apic_bsp_setup() for UP APIC setupThomas Gleixner
Extend apic_bsp_setup() so the same code flow can be used for APIC_init_uniprocessor(). Folded Jiangs fix to provide proper ordering of the UP setup. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Borislav Petkov <bp@alien8.de> Link: http://lkml.kernel.org/r/20150115211704.084765674@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-01-22x86/smpboot: Sanitize uniprocessor initThomas Gleixner
The UP related setups for local apic are mangled into smp_sanity_check(). That results in duplicate calls to disable_smp() and makes the code hard to follow. Let smp_sanity_check() return dedicated values for the various exit reasons and handle them at the call site. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Borislav Petkov <bp@alien8.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Link: http://lkml.kernel.org/r/20150115211703.987833932@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-01-22x86/smpboot: Move apic init code to apic.cThomas Gleixner
We better provide proper functions which implement the required code flow in the apic code rather than letting the smpboot code open code it. That allows to make more functions static and confines the APIC functionality to apic.c where it belongs. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Borislav Petkov <bp@alien8.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Link: http://lkml.kernel.org/r/20150115211703.907616730@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-01-22x86/smpboot: Cleanup ioapic handlingThomas Gleixner
smpboot is very creative with the ways to disable ioapic. smpboot_clear_io_apic() smpboot_clear_io_apic_irqs() and disable_ioapic_support() serve a similar purpose. smpboot_clear_io_apic_irqs() is the most useless of all functions as it clears a variable which has not been setup yet. Aside of that it has the same ifdef mess and conditionals around the ioapic related code, which can now be removed. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Borislav Petkov <bp@alien8.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Link: http://lkml.kernel.org/r/20150115211703.650280684@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-01-22x86/smpboot: Move smpboot inlines to codeThomas Gleixner
No point for a separate header file. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Tony Luck <tony.luck@intel.com> Cc: Borislav Petkov <bp@alien8.de> Link: http://lkml.kernel.org/r/20150115211703.304126687@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-12-16x86, smpboot: Remove pointless preempt_disable() in native_smp_prepare_cpus()Thomas Gleixner
There is no reason to keep preemption disabled in this function. We only have two other threads live: kthreadd and idle. Neither of them is going to preempt. But that preempt_disable forces all the code inside to do GFP_ATOMIC allocations which is just insane. Remove it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Borislav Petkov <bp@alien8.de> Cc: Jiang Liu <jiang.liu@linux.intel.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: x86@kernel.org Link: http://lkml.kernel.org/r/20141205084147.153643952@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-12-10Merge branch 'x86-boot-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 boot and percpu updates from Ingo Molnar: "This tree contains a bootable images documentation update plus three slightly misplaced x86/asm percpu changes/optimizations" * 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86-64: Use RIP-relative addressing for most per-CPU accesses x86-64: Handle PC-relative relocations on per-CPU data x86: Convert a few more per-CPU items to read-mostly ones x86, boot: Document intermediates more clearly
2014-11-10x86/core, x86/xen/smp: Use 'die_complete' completion when taking CPU downBoris Ostrovsky
Commit 2ed53c0d6cc9 ("x86/smpboot: Speed up suspend/resume by avoiding 100ms sleep for CPU offline during S3") introduced completions to CPU offlining process. These completions are not initialized on Xen kernels causing a panic in play_dead_common(). Move handling of die_complete into common routines to make them available to Xen guests. Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: David Vrabel <david.vrabel@citrix.com> Cc: tianyu.lan@intel.com Cc: konrad.wilk@oracle.com Cc: xen-devel@lists.xenproject.org Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/1414770572-7950-1-git-send-email-boris.ostrovsky@oracle.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-11-04x86: Convert a few more per-CPU items to read-mostly onesJan Beulich
Both this_cpu_off and cpu_info aren't getting modified post boot, yet are being accessed on enough code paths that grouping them with other frequently read items seems desirable. For cpu_info this at the same time implies removing the cache line alignment (which afaict became pointless when it got converted to per-CPU data years ago). Signed-off-by: Jan Beulich <jbeulich@suse.com> Link: http://lkml.kernel.org/r/54589BD20200007800044A84@mail.emea.novell.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-10-19x86/smpboot: Move data structure to its primary usage scopeIngo Molnar
Makes the code more readable by moving variable and usage closer to each other, which also avoids this build warning in the !CONFIG_HOTPLUG_CPU case: arch/x86/kernel/smpboot.c:105:42: warning: ‘die_complete’ defined but not used [-Wunused-variable] Cc: Prarit Bhargava <prarit@redhat.com> Cc: Lan Tianyu <tianyu.lan@intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: srostedt@redhat.com Cc: toshi.kani@hp.com Cc: imammedo@redhat.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/1409039025-32310-1-git-send-email-tianyu.lan@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-10-13Merge branch 'x86-cpu-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 cpu offlining patch from Ingo Molnar: "This tree includes a single commit that speeds up x86 suspend/resume by replacing a naive 100msec sleep based polling loop with proper completion notification. This gives some real suspend/resume benefit on servers with larger core counts" * 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/smpboot: Speed up suspend/resume by avoiding 100ms sleep for CPU offline during S3
2014-10-13Merge branch 'x86-boot-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 bootup updates from Ingo Molnar: "The changes in this cycle were: - Fix rare SMP-boot hang (mostly in virtual environments) - Fix build warning with certain (rare) toolchains" * 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/relocs: Make per_cpu_load_addr static x86/smpboot: Initialize secondary CPU only if master CPU will wait for it
2014-10-13Merge branch 'sched-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: "The main changes in this cycle were: - Optimized support for Intel "Cluster-on-Die" (CoD) topologies (Dave Hansen) - Various sched/idle refinements for better idle handling (Nicolas Pitre, Daniel Lezcano, Chuansheng Liu, Vincent Guittot) - sched/numa updates and optimizations (Rik van Riel) - sysbench speedup (Vincent Guittot) - capacity calculation cleanups/refactoring (Vincent Guittot) - Various cleanups to thread group iteration (Oleg Nesterov) - Double-rq-lock removal optimization and various refactorings (Kirill Tkhai) - various sched/deadline fixes ... and lots of other changes" * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (72 commits) sched/dl: Use dl_bw_of() under rcu_read_lock_sched() sched/fair: Delete resched_cpu() from idle_balance() sched, time: Fix build error with 64 bit cputime_t on 32 bit systems sched: Improve sysbench performance by fixing spurious active migration sched/x86: Fix up typo in topology detection x86, sched: Add new topology for multi-NUMA-node CPUs sched/rt: Use resched_curr() in task_tick_rt() sched: Use rq->rd in sched_setaffinity() under RCU read lock sched: cleanup: Rename 'out_unlock' to 'out_free_new_mask' sched: Use dl_bw_of() under RCU read lock sched/fair: Remove duplicate code from can_migrate_task() sched, mips, ia64: Remove __ARCH_WANT_UNLOCKED_CTXSW sched: print_rq(): Don't use tasklist_lock sched: normalize_rt_tasks(): Don't use _irqsave for tasklist_lock, use task_rq_lock() sched: Fix the task-group check in tg_has_rt_tasks() sched/fair: Leverage the idle state info when choosing the "idlest" cpu sched: Let the scheduler see CPU idle states sched/deadline: Fix inter- exclusive cpusets migrations sched/deadline: Clear dl_entity params when setscheduling to different class sched/numa: Kill the wrong/dead TASK_DEAD check in task_numa_fault() ...
2014-10-03sched/x86: Fix up typo in topology detectionDave Hansen
Commit: cebf15eb09a2 ("x86, sched: Add new topology for multi-NUMA-node CPUs") some code to try to detect the situation where we have a NUMA node inside of the "DIE" sched domain. It detected this by looking for cpus which match_die() but do not match NUMA nodes via topology_same_node(). I wrote it up as: if (match_die(c, o) == !topology_same_node(c, o)) which actually seemed to work some of the time, albiet accidentally. It should have been doing an &&, not an ==. This code essentially chopped off the "DIE" domain on one of Andrew Morton's systems. He reported that this patch fixed his issue. Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reported-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Dave Hansen <dave@sr71.net> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: David Rientjes <rientjes@google.com> Cc: Igor Mammedov <imammedo@redhat.com> Cc: Jan Kiszka <jan.kiszka@siemens.com> Cc: Lan Tianyu <tianyu.lan@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Toshi Kani <toshi.kani@hp.com> Link: http://lkml.kernel.org/r/20140930214546.FD481CFF@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-09-24sched: Fix unreleased llc_shared_mask bit during CPU hotplugWanpeng Li
The following bug can be triggered by hot adding and removing a large number of xen domain0's vcpus repeatedly: BUG: unable to handle kernel NULL pointer dereference at 0000000000000004 IP: [..] find_busiest_group PGD 5a9d5067 PUD 13067 PMD 0 Oops: 0000 [#3] SMP [...] Call Trace: load_balance ? _raw_spin_unlock_irqrestore idle_balance __schedule schedule schedule_timeout ? lock_timer_base schedule_timeout_uninterruptible msleep lock_device_hotplug_sysfs online_store dev_attr_store sysfs_write_file vfs_write SyS_write system_call_fastpath Last level cache shared mask is built during CPU up and the build_sched_domain() routine takes advantage of it to setup the sched domain CPU topology. However, llc_shared_mask is not released during CPU disable, which leads to an invalid sched domainCPU topology. This patch fix it by releasing the llc_shared_mask correctly during CPU disable. Yasuaki also reported that this can happen on real hardware: https://lkml.org/lkml/2014/7/22/1018 His case is here: == Here is an example on my system. My system has 4 sockets and each socket has 15 cores and HT is enabled. In this case, each core of sockes is numbered as follows: | CPU# Socket#0 | 0-14 , 60-74 Socket#1 | 15-29, 75-89 Socket#2 | 30-44, 90-104 Socket#3 | 45-59, 105-119 Then llc_shared_mask of CPU#30 has 0x3fff80000001fffc0000000. It means that last level cache of Socket#2 is shared with CPU#30-44 and 90-104. When hot-removing socket#2 and #3, each core of sockets is numbered as follows: | CPU# Socket#0 | 0-14 , 60-74 Socket#1 | 15-29, 75-89 But llc_shared_mask is not cleared. So llc_shared_mask of CPU#30 remains having 0x3fff80000001fffc0000000. After that, when hot-adding socket#2 and #3, each core of sockets is numbered as follows: | CPU# Socket#0 | 0-14 , 60-74 Socket#1 | 15-29, 75-89 Socket#2 | 30-59 Socket#3 | 90-119 Then llc_shared_mask of CPU#30 becomes 0x3fff8000fffffffc0000000. It means that last level cache of Socket#2 is shared with CPU#30-59 and 90-104. So the mask has the wrong value. Signed-off-by: Wanpeng Li <wanpeng.li@linux.intel.com> Tested-by: Linn Crosetto <linn@hp.com> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Toshi Kani <toshi.kani@hp.com> Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: <stable@vger.kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Steven Rostedt <srostedt@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/1411547885-48165-1-git-send-email-wanpeng.li@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-09-24x86/smpboot: Speed up suspend/resume by avoiding 100ms sleep for CPU offline ↵Lan Tianyu
during S3 With certain kernel configurations, CPU offline consumes more than 100ms during S3. It's a timing related issue: native_cpu_die() would occasionally fall into a 100ms sleep when the CPU idle loop thread marked the CPU state to DEAD too slowly. What native_cpu_die() does is that it polls the CPU state and waits for 100ms if CPU state hasn't been marked to DEAD. The 100ms sleep doesn't make sense and is purely historic. To avoid such long sleeping, this patch adds a 'struct completion' to each CPU, waits for the completion in native_cpu_die() and wakes up the completion when the CPU state is marked to DEAD. Tested on an Intel Xeon server with 48 cores, Ivybridge and on Haswell laptops. The CPU offlining cost on these machines is reduced from more than 100ms to less than 5ms. The system suspend time is reduced by 2.3s on the servers. Borislav and Prarit also helped to test the patch on an AMD machine and a few systems of various sizes and configurations (multi-socket, single-socket, no hyper threading, etc.). No issues were seen. Tested-by: Prarit Bhargava <prarit@redhat.com> Signed-off-by: Lan Tianyu <tianyu.lan@intel.com> Acked-by: Borislav Petkov <bp@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: srostedt@redhat.com Cc: toshi.kani@hp.com Cc: imammedo@redhat.com Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/1409039025-32310-1-git-send-email-tianyu.lan@intel.com [ Improved a few minor details in the code, cleaned up the changelog. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-09-24x86, sched: Add new topology for multi-NUMA-node CPUsDave Hansen
I'm getting the spew below when booting with Haswell (Xeon E5-2699 v3) CPUs and the "Cluster-on-Die" (CoD) feature enabled in the BIOS. It seems similar to the issue that some folks from AMD ran in to on their systems and addressed in this commit: 161270fc1f9d ("x86/smp: Fix topology checks on AMD MCM CPUs") Both these Intel and AMD systems break an assumption which is being enforced by topology_sane(): a socket may not contain more than one NUMA node. AMD special-cased their system by looking for a cpuid flag. The Intel mode is dependent on BIOS options and I do not know of a way which it is enumerated other than the tables being parsed during the CPU bringup process. In other words, we have to trust the ACPI tables <shudder>. This detects the situation where a NUMA node occurs at a place in the middle of the "CPU" sched domains. It replaces the default topology with one that relies on the NUMA information from the firmware (SRAT table) for all levels of sched domains above the hyperthreads. This also fixes a sysfs bug. We used to freak out when we saw the "mc" group cross a node boundary, so we stopped building the MC group. MC gets exported as the 'core_siblings_list' in /sys/devices/system/cpu/cpu*/topology/ and this caused CPUs with the same 'physical_package_id' to not be listed together in 'core_siblings_list'. This violates a statement from Documentation/ABI/testing/sysfs-devices-system-cpu: core_siblings: internal kernel map of cpu#'s hardware threads within the same physical_package_id. core_siblings_list: human-readable list of the logical CPU numbers within the same physical_package_id as cpu#. The sysfs effects here cause an issue with the hwloc tool where it gets confused and thinks there are more sockets than are physically present. Before this patch, there are two packages: # cd /sys/devices/system/cpu/ # cat cpu*/topology/physical_package_id | sort | uniq -c 18 0 18 1 But 4 _sets_ of core siblings: # cat cpu*/topology/core_siblings_list | sort | uniq -c 9 0-8 9 18-26 9 27-35 9 9-17 After this set, there are only 2 sets of core siblings, which is what we expect for a 2-socket system. # cat cpu*/topology/physical_package_id | sort | uniq -c 18 0 18 1 # cat cpu*/topology/core_siblings_list | sort | uniq -c 18 0-17 18 18-35 Example spew: ... NMI watchdog: enabled on all CPUs, permanently consumes one hw-PMU counter. #2 #3 #4 #5 #6 #7 #8 .... node #1, CPUs: #9 ------------[ cut here ]------------ WARNING: CPU: 9 PID: 0 at /home/ak/hle/linux-hle-2.6/arch/x86/kernel/smpboot.c:306 topology_sane.isra.2+0x74/0x90() sched: CPU #9's mc-sibling CPU #0 is not on the same node! [node: 1 != 0]. Ignoring dependency. Modules linked in: CPU: 9 PID: 0 Comm: swapper/9 Not tainted 3.17.0-rc1-00293-g8e01c4d-dirty #631 Hardware name: Intel Corporation S2600WTT/S2600WTT, BIOS GRNDSDP1.86B.0036.R05.1407140519 07/14/2014 0000000000000009 ffff88046ddabe00 ffffffff8172e485 ffff88046ddabe48 ffff88046ddabe38 ffffffff8109691d 000000000000b001 0000000000000009 ffff88086fc12580 000000000000b020 0000000000000009 ffff88046ddabe98 Call Trace: [<ffffffff8172e485>] dump_stack+0x45/0x56 [<ffffffff8109691d>] warn_slowpath_common+0x7d/0xa0 [<ffffffff8109698c>] warn_slowpath_fmt+0x4c/0x50 [<ffffffff81074f94>] topology_sane.isra.2+0x74/0x90 [<ffffffff8107530e>] set_cpu_sibling_map+0x31e/0x4f0 [<ffffffff8107568d>] start_secondary+0x1ad/0x240 ---[ end trace 3fe5f587a9fcde61 ]--- #10 #11 #12 #13 #14 #15 #16 #17 .... node #2, CPUs: #18 #19 #20 #21 #22 #23 #24 #25 #26 .... node #3, CPUs: #27 #28 #29 #30 #31 #32 #33 #34 #35 Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> [ Added LLC domain and s/match_mc/match_die/ ] Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: David Rientjes <rientjes@google.com> Cc: Igor Mammedov <imammedo@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Toshi Kani <toshi.kani@hp.com> Cc: brice.goglin@gmail.com Cc: "H. Peter Anvin" <hpa@linux.intel.com> Link: http://lkml.kernel.org/r/20140918193334.C065EBCE@viggo.jf.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-09-16x86/smpboot: Initialize secondary CPU only if master CPU will wait for itIgor Mammedov
Hang is observed on virtual machines during CPU hotplug, especially in big guests with many CPUs. (It reproducible more often if host is over-committed). It happens because master CPU gives up waiting on secondary CPU and allows it to run wild. As result AP causes locking or crashing system. For example as described here: https://lkml.org/lkml/2014/3/6/257 If master CPU have sent STARTUP IPI successfully, and AP signalled to master CPU that it's ready to start initialization, make master CPU wait indefinitely till AP is onlined. To ensure that AP won't ever run wild, make it wait at early startup till master CPU confirms its intention to wait for AP. If AP doesn't respond in 10 seconds, the master CPU will timeout and cancel AP onlining. Signed-off-by: Igor Mammedov <imammedo@redhat.com> Acked-by: Toshi Kani <toshi.kani@hp.com> Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/1403266991-12233-1-git-send-email-imammedo@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-07-31x86, apic: Remove setup_portio_remap callbackDavid Rientjes
Since commit b5660ba76b41 ("x86, platforms: Remove NUMAQ") removed NUMAQ, the setup_portio_remap() apic callback has been obsolete. Remove it. Signed-off-by: David Rientjes <rientjes@google.com> Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1407302351480.17503@chino.kir.corp.google.com Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2014-07-31x86, apic: Remove smp_callin_clear_local_apic callbackDavid Rientjes
Since commit b5660ba76b41 ("x86, platforms: Remove NUMAQ") removed NUMAQ, the smp_callin_clear_local_apic() apic callback has been obsolete. Remove it. Signed-off-by: David Rientjes <rientjes@google.com> Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1407302349040.17503@chino.kir.corp.google.com Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2014-06-08Merge branch 'next' (accumulated 3.16 merge window patches) into masterLinus Torvalds
Now that 3.15 is released, this merges the 'next' branch into 'master', bringing us to the normal situation where my 'master' branch is the merge window. * accumulated work in next: (6809 commits) ufs: sb mutex merge + mutex_destroy powerpc: update comments for generic idle conversion cris: update comments for generic idle conversion idle: remove cpu_idle() forward declarations nbd: zero from and len fields in NBD_CMD_DISCONNECT. mm: convert some level-less printks to pr_* MAINTAINERS: adi-buildroot-devel is moderated MAINTAINERS: add linux-api for review of API/ABI changes mm/kmemleak-test.c: use pr_fmt for logging fs/dlm/debug_fs.c: replace seq_printf by seq_puts fs/dlm/lockspace.c: convert simple_str to kstr fs/dlm/config.c: convert simple_str to kstr mm: mark remap_file_pages() syscall as deprecated mm: memcontrol: remove unnecessary memcg argument from soft limit functions mm: memcontrol: clean up memcg zoneinfo lookup mm/memblock.c: call kmemleak directly from memblock_(alloc|free) mm/mempool.c: update the kmemleak stack trace for mempool allocations lib/radix-tree.c: update the kmemleak stack trace for radix tree allocations mm: introduce kmemleak_update_trace() mm/kmemleak.c: use %u to print ->checksum ...
2014-06-08Revert "x86/smpboot: Initialize secondary CPU only if master CPU will wait ↵Linus Torvalds
for it" This reverts commit 3e1a878b7ccdb31da6d9d2b855c72ad87afeba3f. It came in very late, and already has one reported failure: Sitsofe reports that the current tree fails to boot on his EeePC, and bisected it down to this. Rather than waste time trying to figure out what's wrong, just revert it. Reported-by: Sitsofe Wheeler <sitsofe@gmail.com> Cc: Igor Mammedov <imammedo@redhat.com> Cc: Toshi Kani <toshi.kani@hp.com> Cc: Thomas Gleixner <tglx@linutronix.de> Acked-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-05x86/smpboot: Initialize secondary CPU only if master CPU will wait for itIgor Mammedov
Hang is observed on virtual machines during CPU hotplug, especially in big guests with many CPUs. (It reproducible more often if host is over-committed). It happens because master CPU gives up waiting on secondary CPU and allows it to run wild. As result AP causes locking or crashing system. For example as described here: https://lkml.org/lkml/2014/3/6/257 If master CPU have sent STARTUP IPI successfully, and AP signalled to master CPU that it's ready to start initialization, make master CPU wait indefinitely till AP is onlined. To ensure that AP won't ever run wild, make it wait at early startup till master CPU confirms its intention to wait for AP. If AP doesn't respond in 10 seconds, the master CPU will timeout and cancel AP onlining. Signed-off-by: Igor Mammedov <imammedo@redhat.com> Acked-by: Toshi Kani <toshi.kani@hp.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1401975765-22328-4-git-send-email-imammedo@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-06-05x86/smpboot: Log error on secondary CPU wakeup failure at ERR levelIgor Mammedov
If system is running without debug level logging, it will not log error if do_boot_cpu() failed to wakeup AP. It may lead to silent AP bringup failures at boot time. Change message level to KERN_ERR to make error visible to user as it's done on other architectures. Signed-off-by: Igor Mammedov <imammedo@redhat.com> Acked-by: Toshi Kani <toshi.kani@hp.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1401975765-22328-3-git-send-email-imammedo@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-06-05x86: Fix list/memory corruption on CPU hotplugIgor Mammedov
currently if AP wake up is failed, master CPU marks AP as not present in do_boot_cpu() by calling set_cpu_present(cpu, false). That leads to following list corruption on the next physical CPU hotplug: [ 418.107336] WARNING: CPU: 1 PID: 45 at lib/list_debug.c:33 __list_add+0xbe/0xd0() [ 418.115268] list_add corruption. prev->next should be next (ffff88003dc57600), but was ffff88003e20c3a0. (prev=ffff88003e20c3a0). [ 418.123693] Modules linked in: nf_conntrack_netbios_ns nf_conntrack_broadcast ipt_MASQUERADE ip6t_REJECT ipt_REJECT cfg80211 xt_conntrack rfkill ee [ 418.138979] CPU: 1 PID: 45 Comm: kworker/u10:1 Not tainted 3.14.0-rc6+ #387 [ 418.149989] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2007 [ 418.165750] Workqueue: kacpi_hotplug acpi_hotplug_work_fn [ 418.166433] 0000000000000021 ffff880038ca7988 ffffffff8159b22d 0000000000000021 [ 418.176460] ffff880038ca79d8 ffff880038ca79c8 ffffffff8106942c ffff880038ca79e8 [ 418.177453] ffff88003e20c3a0 ffff88003dc57600 ffff88003e20c3a0 00000000ffffffea [ 418.178445] Call Trace: [ 418.185811] [<ffffffff8159b22d>] dump_stack+0x49/0x5c [ 418.186440] [<ffffffff8106942c>] warn_slowpath_common+0x8c/0xc0 [ 418.187192] [<ffffffff81069516>] warn_slowpath_fmt+0x46/0x50 [ 418.191231] [<ffffffff8136ef51>] ? acpi_ns_get_node+0xb7/0xc7 [ 418.193889] [<ffffffff812f796e>] __list_add+0xbe/0xd0 [ 418.196649] [<ffffffff812e2aa9>] kobject_add_internal+0x79/0x200 [ 418.208610] [<ffffffff812e2e18>] kobject_add_varg+0x38/0x60 [ 418.213831] [<ffffffff812e2ef4>] kobject_add+0x44/0x70 [ 418.229961] [<ffffffff813e2c60>] device_add+0xd0/0x550 [ 418.234991] [<ffffffff813f0e95>] ? pm_runtime_init+0xe5/0xf0 [ 418.250226] [<ffffffff813e32be>] device_register+0x1e/0x30 [ 418.255296] [<ffffffff813e82a3>] register_cpu+0xe3/0x130 [ 418.266539] [<ffffffff81592be5>] arch_register_cpu+0x65/0x150 [ 418.285845] [<ffffffff81355c0d>] acpi_processor_hotadd_init+0x5a/0x9b ... Which is caused by the fact that generic_processor_info() allocates logical CPU id by calling: cpu = cpumask_next_zero(-1, cpu_present_mask); which returns id of previously failed to wake up CPU, since its bit is cleared by do_boot_cpu() and as result register_cpu() tries to register another CPU with the same id as already present but failed to be onlined CPU. Taking in account that AP will not do anything if master CPU failed to wake it up, there is no reason to mark that AP as not present and break next cpu hotplug attempts. As a side effect of not marking AP as not present, user would be allowed to online it again later. Also fix memory corruption in acpi_unmap_lsapic() if during CPU hotplug master CPU failed to wake up AP it set percpu x86_cpu_to_apicid to BAD_APICID=0xFFFF for AP. However following attempt to unplug that CPU will lead to out of bound write access to __apicid_to_node[] which is 32768 items long on x86_64 kernel. So with above fix of cpu_present_mask make sure that a present CPU has a valid APIC ID by not setting x86_cpu_to_apicid to BAD_APICID in do_boot_cpu() on failure and allow acpi_processor_remove()->acpi_unmap_lsapic() cleanly remove CPU. Signed-off-by: Igor Mammedov <imammedo@redhat.com> Acked-by: Toshi Kani <toshi.kani@hp.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1401975765-22328-2-git-send-email-imammedo@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-05-04x86, espfix: Make espfix64 a Kconfig option, fix UMLH. Peter Anvin
Make espfix64 a hidden Kconfig option. This fixes the x86-64 UML build which had broken due to the non-existence of init_espfix_bsp() in UML: since UML uses its own Kconfig, this option does not appear in the UML build. This also makes it possible to make support for 16-bit segments a configuration option, for the people who want to minimize the size of the kernel. Reported-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: Richard Weinberger <richard@nod.at> Link: http://lkml.kernel.org/r/1398816946-3351-1-git-send-email-hpa@linux.intel.com
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