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* Merge branch 'x86-platform-for-linus' of ↵Linus Torvalds2017-11-131-4/+5
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 platform updates from Ingo Molnar: "The main changes in this cycle were: - a refactoring of the early virt init code by merging 'struct x86_hyper' into 'struct x86_platform' and 'struct x86_init', which allows simplifications and also the addition of a new ->guest_late_init() callback. (Juergen Gross) - timer_setup() conversion of the UV code (Kees Cook)" * 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/virt/xen: Use guest_late_init to detect Xen PVH guest x86/virt, x86/platform: Add ->guest_late_init() callback to hypervisor_x86 structure x86/virt, x86/acpi: Add test for ACPI_FADT_NO_VGA x86/virt: Add enum for hypervisors to replace x86_hyper x86/virt, x86/platform: Merge 'struct x86_hyper' into 'struct x86_platform' and 'struct x86_init' x86/platform/UV: Convert timers to use timer_setup()
| * x86/virt, x86/platform: Add ->guest_late_init() callback to hypervisor_x86 ↵Juergen Gross2017-11-101-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | structure Add a new guest_late_init callback to the hypervisor_x86 structure. It will replace the current kvm_guest_init() call which is changed to make use of the new callback. Signed-off-by: Juergen Gross <jgross@suse.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: kvm@vger.kernel.org Cc: rkrcmar@redhat.com Link: http://lkml.kernel.org/r/20171109132739.23465-5-jgross@suse.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * x86/virt: Add enum for hypervisors to replace x86_hyperJuergen Gross2017-11-101-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The x86_hyper pointer is only used for checking whether a virtual device is supporting the hypervisor the system is running on. Use an enum for that purpose instead and drop the x86_hyper pointer. Signed-off-by: Juergen Gross <jgross@suse.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Xavier Deguillard <xdeguillard@vmware.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: akataria@vmware.com Cc: arnd@arndb.de Cc: boris.ostrovsky@oracle.com Cc: devel@linuxdriverproject.org Cc: dmitry.torokhov@gmail.com Cc: gregkh@linuxfoundation.org Cc: haiyangz@microsoft.com Cc: kvm@vger.kernel.org Cc: kys@microsoft.com Cc: linux-graphics-maintainer@vmware.com Cc: linux-input@vger.kernel.org Cc: moltmann@vmware.com Cc: pbonzini@redhat.com Cc: pv-drivers@vmware.com Cc: rkrcmar@redhat.com Cc: sthemmin@microsoft.com Cc: virtualization@lists.linux-foundation.org Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/20171109132739.23465-3-jgross@suse.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * x86/virt, x86/platform: Merge 'struct x86_hyper' into 'struct x86_platform' ↵Juergen Gross2017-11-101-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | and 'struct x86_init' Instead of x86_hyper being either NULL on bare metal or a pointer to a struct hypervisor_x86 in case of the kernel running as a guest merge the struct into x86_platform and x86_init. This will remove the need for wrappers making it hard to find out what is being called. With dummy functions added for all callbacks testing for a NULL function pointer can be removed, too. Suggested-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Juergen Gross <jgross@suse.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: akataria@vmware.com Cc: boris.ostrovsky@oracle.com Cc: devel@linuxdriverproject.org Cc: haiyangz@microsoft.com Cc: kvm@vger.kernel.org Cc: kys@microsoft.com Cc: pbonzini@redhat.com Cc: rkrcmar@redhat.com Cc: rusty@rustcorp.com.au Cc: sthemmin@microsoft.com Cc: virtualization@lists.linux-foundation.org Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/20171109132739.23465-2-jgross@suse.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | X86/KVM: Decrypt shared per-cpu variables when SEV is activeBrijesh Singh2017-11-071-3/+37
|/ | | | | | | | | | | | | | | | | | When SEV is active, guest memory is encrypted with a guest-specific key, a guest memory region shared with the hypervisor must be mapped as decrypted before it can be shared. Signed-off-by: Brijesh Singh <brijesh.singh@amd.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Tested-by: Borislav Petkov <bp@suse.de> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: kvm@vger.kernel.org Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Paolo Bonzini <pbonzini@redhat.com> Link: https://lkml.kernel.org/r/20171020143059.3291-17-brijesh.singh@amd.com
* kvm/x86: Avoid async PF preempting the kernel incorrectlyBoqun Feng2017-10-041-4/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, in PREEMPT_COUNT=n kernel, kvm_async_pf_task_wait() could call schedule() to reschedule in some cases. This could result in accidentally ending the current RCU read-side critical section early, causing random memory corruption in the guest, or otherwise preempting the currently running task inside between preempt_disable and preempt_enable. The difficulty to handle this well is because we don't know whether an async PF delivered in a preemptible section or RCU read-side critical section for PREEMPT_COUNT=n, since preempt_disable()/enable() and rcu_read_lock/unlock() are both no-ops in that case. To cure this, we treat any async PF interrupting a kernel context as one that cannot be preempted, preventing kvm_async_pf_task_wait() from choosing the schedule() path in that case. To do so, a second parameter for kvm_async_pf_task_wait() is introduced, so that we know whether it's called from a context interrupting the kernel, and the parameter is set properly in all the callsites. Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Wanpeng Li <wanpeng.li@hotmail.com> Cc: stable@vger.kernel.org Signed-off-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
* kvm/x86: Handle async PF in RCU read-side critical sectionsBoqun Feng2017-09-291-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Sasha Levin reported a WARNING: | WARNING: CPU: 0 PID: 6974 at kernel/rcu/tree_plugin.h:329 | rcu_preempt_note_context_switch kernel/rcu/tree_plugin.h:329 [inline] | WARNING: CPU: 0 PID: 6974 at kernel/rcu/tree_plugin.h:329 | rcu_note_context_switch+0x16c/0x2210 kernel/rcu/tree.c:458 ... | CPU: 0 PID: 6974 Comm: syz-fuzzer Not tainted 4.13.0-next-20170908+ #246 | Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS | 1.10.1-1ubuntu1 04/01/2014 | Call Trace: ... | RIP: 0010:rcu_preempt_note_context_switch kernel/rcu/tree_plugin.h:329 [inline] | RIP: 0010:rcu_note_context_switch+0x16c/0x2210 kernel/rcu/tree.c:458 | RSP: 0018:ffff88003b2debc8 EFLAGS: 00010002 | RAX: 0000000000000001 RBX: 1ffff1000765bd85 RCX: 0000000000000000 | RDX: 1ffff100075d7882 RSI: ffffffffb5c7da20 RDI: ffff88003aebc410 | RBP: ffff88003b2def30 R08: dffffc0000000000 R09: 0000000000000001 | R10: 0000000000000000 R11: 0000000000000000 R12: ffff88003b2def08 | R13: 0000000000000000 R14: ffff88003aebc040 R15: ffff88003aebc040 | __schedule+0x201/0x2240 kernel/sched/core.c:3292 | schedule+0x113/0x460 kernel/sched/core.c:3421 | kvm_async_pf_task_wait+0x43f/0x940 arch/x86/kernel/kvm.c:158 | do_async_page_fault+0x72/0x90 arch/x86/kernel/kvm.c:271 | async_page_fault+0x22/0x30 arch/x86/entry/entry_64.S:1069 | RIP: 0010:format_decode+0x240/0x830 lib/vsprintf.c:1996 | RSP: 0018:ffff88003b2df520 EFLAGS: 00010283 | RAX: 000000000000003f RBX: ffffffffb5d1e141 RCX: ffff88003b2df670 | RDX: 0000000000000001 RSI: dffffc0000000000 RDI: ffffffffb5d1e140 | RBP: ffff88003b2df560 R08: dffffc0000000000 R09: 0000000000000000 | R10: ffff88003b2df718 R11: 0000000000000000 R12: ffff88003b2df5d8 | R13: 0000000000000064 R14: ffffffffb5d1e140 R15: 0000000000000000 | vsnprintf+0x173/0x1700 lib/vsprintf.c:2136 | sprintf+0xbe/0xf0 lib/vsprintf.c:2386 | proc_self_get_link+0xfb/0x1c0 fs/proc/self.c:23 | get_link fs/namei.c:1047 [inline] | link_path_walk+0x1041/0x1490 fs/namei.c:2127 ... This happened when the host hit a page fault, and delivered it as in an async page fault, while the guest was in an RCU read-side critical section. The guest then tries to reschedule in kvm_async_pf_task_wait(), but rcu_preempt_note_context_switch() would treat the reschedule as a sleep in RCU read-side critical section, which is not allowed (even in preemptible RCU). Thus the WARN. To cure this, make kvm_async_pf_task_wait() go to the halt path if the PF happens in a RCU read-side critical section. Reported-by: Sasha Levin <levinsasha928@gmail.com> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: stable@vger.kernel.org Signed-off-by: Boqun Feng <boqun.feng@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* kvm,x86: Fix apf_task_wake_one() wq serializationDavidlohr Bueso2017-09-151-1/+1
| | | | | | | | | | | | | | | | | During code inspection, the following potential race was seen: CPU0 CPU1 kvm_async_pf_task_wait apf_task_wake_one [L] swait_active(&n->wq) [S] prepare_to_swait(&n.wq) [L] if (!hlist_unhahed(&n.link)) schedule() [S] hlist_del_init(&n->link); Properly serialize swait_active() checks such that a wakeup is not missed. Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* x86/idt: Hide set_intr_gate()Thomas Gleixner2017-08-291-1/+1
| | | | | | | | | | | | | | | | | | | | | | | set_intr_gate() is an internal function of the IDT code. The only user left is the KVM code which replaces the pagefault handler eventually. Provide an explicit update_intr_gate() function and make set_intr_gate() static. While at it replace the magic number 14 in the KVM code with the proper trap define. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Cc: Andy 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: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/20170828064959.663008004@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
* x86/traps: Simplify pagefault tracing logicThomas Gleixner2017-08-291-1/+1
| | | | | | | | | | | | | | | | | | Make use of the new irqvector tracing static key and remove the duplicated trace_do_pagefault() implementation. If irq vector tracing is disabled, then the overhead of this is a single NOP5, which is a reasonable tradeoff to avoid duplicated code and the unholy macro mess. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/20170828064956.672965407@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
* KVM: async_pf: make rcu irq exit if not triggered from idle taskWanpeng Li2017-08-011-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | WARNING: CPU: 5 PID: 1242 at kernel/rcu/tree_plugin.h:323 rcu_note_context_switch+0x207/0x6b0 CPU: 5 PID: 1242 Comm: unity-settings- Not tainted 4.13.0-rc2+ #1 RIP: 0010:rcu_note_context_switch+0x207/0x6b0 Call Trace: __schedule+0xda/0xba0 ? kvm_async_pf_task_wait+0x1b2/0x270 schedule+0x40/0x90 kvm_async_pf_task_wait+0x1cc/0x270 ? prepare_to_swait+0x22/0x70 do_async_page_fault+0x77/0xb0 ? do_async_page_fault+0x77/0xb0 async_page_fault+0x28/0x30 RIP: 0010:__d_lookup_rcu+0x90/0x1e0 I encounter this when trying to stress the async page fault in L1 guest w/ L2 guests running. Commit 9b132fbe5419 (Add rcu user eqs exception hooks for async page fault) adds rcu_irq_enter/exit() to kvm_async_pf_task_wait() to exit cpu idle eqs when needed, to protect the code that needs use rcu. However, we need to call the pair even if the function calls schedule(), as seen from the above backtrace. This patch fixes it by informing the RCU subsystem exit/enter the irq towards/away from idle for both n.halted and !n.halted. Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: stable@vger.kernel.org Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
* KVM: async_pf: Let guest support delivery of async_pf from guest modeWanpeng Li2017-07-141-1/+6
| | | | | | | | | | | | | | | | Adds another flag bit (bit 2) to MSR_KVM_ASYNC_PF_EN. If bit 2 is 1, async page faults are delivered to L1 as #PF vmexits; if bit 2 is 0, kvm_can_do_async_pf returns 0 if in guest mode. This is similar to what svm.c wanted to do all along, but it is only enabled for Linux as L1 hypervisor. Foreign hypervisors must never receive async page faults as vmexits, because they'd probably be very confused about that. Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
* kvm: async_pf: fix rcu_irq_enter() with irqs enabledPaolo Bonzini2017-06-061-1/+1
| | | | | | | | | | | | | | native_safe_halt enables interrupts, and you just shouldn't call rcu_irq_enter() with interrupts enabled. Reorder the call with the following local_irq_disable() to respect the invariant. Reported-by: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Tested-by: Wanpeng Li <wanpeng.li@hotmail.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
* x86/kvm: virt_xxx memory barriers instead of mandatory barriersWanpeng Li2017-04-121-2/+2
| | | | | | | | | | | | | | virt_xxx memory barriers are implemented trivially using the low-level __smp_xxx macros, __smp_xxx is equal to a compiler barrier for strong TSO memory model, however, mandatory barriers will unconditional add memory barriers, this patch replaces the rmb() in kvm_steal_clock() by virt_rmb(). Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
* Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2017-02-221-1/+25
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull KVM updates from Paolo Bonzini: "4.11 is going to be a relatively large release for KVM, with a little over 200 commits and noteworthy changes for most architectures. ARM: - GICv3 save/restore - cache flushing fixes - working MSI injection for GICv3 ITS - physical timer emulation MIPS: - various improvements under the hood - support for SMP guests - a large rewrite of MMU emulation. KVM MIPS can now use MMU notifiers to support copy-on-write, KSM, idle page tracking, swapping, ballooning and everything else. KVM_CAP_READONLY_MEM is also supported, so that writes to some memory regions can be treated as MMIO. The new MMU also paves the way for hardware virtualization support. PPC: - support for POWER9 using the radix-tree MMU for host and guest - resizable hashed page table - bugfixes. s390: - expose more features to the guest - more SIMD extensions - instruction execution protection - ESOP2 x86: - improved hashing in the MMU - faster PageLRU tracking for Intel CPUs without EPT A/D bits - some refactoring of nested VMX entry/exit code, preparing for live migration support of nested hypervisors - expose yet another AVX512 CPUID bit - host-to-guest PTP support - refactoring of interrupt injection, with some optimizations thrown in and some duct tape removed. - remove lazy FPU handling - optimizations of user-mode exits - optimizations of vcpu_is_preempted() for KVM guests generic: - alternative signaling mechanism that doesn't pound on tsk->sighand->siglock" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (195 commits) x86/kvm: Provide optimized version of vcpu_is_preempted() for x86-64 x86/paravirt: Change vcp_is_preempted() arg type to long KVM: VMX: use correct vmcs_read/write for guest segment selector/base x86/kvm/vmx: Defer TR reload after VM exit x86/asm/64: Drop __cacheline_aligned from struct x86_hw_tss x86/kvm/vmx: Simplify segment_base() x86/kvm/vmx: Get rid of segment_base() on 64-bit kernels x86/kvm/vmx: Don't fetch the TSS base from the GDT x86/asm: Define the kernel TSS limit in a macro kvm: fix page struct leak in handle_vmon KVM: PPC: Book3S HV: Disable HPT resizing on POWER9 for now KVM: Return an error code only as a constant in kvm_get_dirty_log() KVM: Return an error code only as a constant in kvm_get_dirty_log_protect() KVM: Return directly after a failed copy_from_user() in kvm_vm_compat_ioctl() KVM: x86: remove code for lazy FPU handling KVM: race-free exit from KVM_RUN without POSIX signals KVM: PPC: Book3S HV: Turn "KVM guest htab" message into a debug message KVM: PPC: Book3S PR: Ratelimit copy data failure error messages KVM: Support vCPU-based gfn->hva cache KVM: use separate generations for each address space ...
| * x86/kvm: Provide optimized version of vcpu_is_preempted() for x86-64Waiman Long2017-02-211-0/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It was found when running fio sequential write test with a XFS ramdisk on a KVM guest running on a 2-socket x86-64 system, the %CPU times as reported by perf were as follows: 69.75% 0.59% fio [k] down_write 69.15% 0.01% fio [k] call_rwsem_down_write_failed 67.12% 1.12% fio [k] rwsem_down_write_failed 63.48% 52.77% fio [k] osq_lock 9.46% 7.88% fio [k] __raw_callee_save___kvm_vcpu_is_preempt 3.93% 3.93% fio [k] __kvm_vcpu_is_preempted Making vcpu_is_preempted() a callee-save function has a relatively high cost on x86-64 primarily due to at least one more cacheline of data access from the saving and restoring of registers (8 of them) to and from stack as well as one more level of function call. To reduce this performance overhead, an optimized assembly version of the the __raw_callee_save___kvm_vcpu_is_preempt() function is provided for x86-64. With this patch applied on a KVM guest on a 2-socket 16-core 32-thread system with 16 parallel jobs (8 on each socket), the aggregrate bandwidth of the fio test on an XFS ramdisk were as follows: I/O Type w/o patch with patch -------- --------- ---------- random read 8141.2 MB/s 8497.1 MB/s seq read 8229.4 MB/s 8304.2 MB/s random write 1675.5 MB/s 1701.5 MB/s seq write 1681.3 MB/s 1699.9 MB/s There are some increases in the aggregated bandwidth because of the patch. The perf data now became: 70.78% 0.58% fio [k] down_write 70.20% 0.01% fio [k] call_rwsem_down_write_failed 69.70% 1.17% fio [k] rwsem_down_write_failed 59.91% 55.42% fio [k] osq_lock 10.14% 10.14% fio [k] __kvm_vcpu_is_preempted The assembly code was verified by using a test kernel module to compare the output of C __kvm_vcpu_is_preempted() and that of assembly __raw_callee_save___kvm_vcpu_is_preempt() to verify that they matched. Suggested-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Waiman Long <longman@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| * x86/paravirt: Change vcp_is_preempted() arg type to longWaiman Long2017-02-211-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | The cpu argument in the function prototype of vcpu_is_preempted() is changed from int to long. That makes it easier to provide a better optimized assembly version of that function. For Xen, vcpu_is_preempted(long) calls xen_vcpu_stolen(int), the downcast from long to int is not a problem as vCPU number won't exceed 32 bits. Signed-off-by: Waiman Long <longman@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | locking/spinlocks/x86, paravirt: Remove paravirt_ticketlocks_enabledWaiman Long2017-01-141-14/+0
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is a follow-up of commit: cfd8983f03c7b2 ("x86, locking/spinlocks: Remove ticket (spin)lock implementation") The static_key structure 'paravirt_ticketlocks_enabled' is now removed as it is no longer used. As a result, the init functions kvm_spinlock_init_jump() and xen_init_spinlocks_jump() are also removed. A simple build and boot test was done to verify it. Signed-off-by: Waiman Long <longman@redhat.com> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Alok Kataria <akataria@vmware.com> Cc: Chris Wright <chrisw@sous-sol.org> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Juergen Gross <jgross@suse.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kvm@vger.kernel.org Cc: linux-arch@vger.kernel.org Cc: virtualization@lists.linux-foundation.org Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/1484252878-1962-1-git-send-email-longman@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* Merge branch 'x86-idle-for-linus' of ↵Linus Torvalds2016-12-121-3/+0
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 idle updates from Ingo Molnar: "There were two bigger changes in this development cycle: - remove idle notifiers: 32 files changed, 74 insertions(+), 803 deletions(-) These notifiers were of questionable value and the main usecase, the i7300 driver, was essentially unmaintained and can be removed, plus modern power management concepts don't need the callback - so use this golden opportunity and get rid of this opaque and fragile callback from a latency sensitive code path. (Len Brown, Thomas Gleixner) - improve the AMD Erratum 400 workaround that used high overhead MSR polling in the idle loop (Borisla Petkov, Thomas Gleixner)" * 'x86-idle-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86: Remove empty idle.h header x86/amd: Simplify AMD E400 aware idle routine x86/amd: Check for the C1E bug post ACPI subsystem init x86/bugs: Separate AMD E400 erratum and C1E bug x86/cpufeature: Provide helper to set bugs bits x86/idle: Remove enter_idle(), exit_idle() x86: Remove x86_test_and_clear_bit_percpu() x86/idle: Remove is_idle flag x86/idle: Remove idle_notifier i7300_idle: Remove this driver
| * x86: Remove empty idle.h headerThomas Gleixner2016-12-091-1/+0
| | | | | | | | | | | | | | | | | | | | | | One include less is always a good thing(tm). Good riddance. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Jiri Olsa <jolsa@redhat.com> Link: http://lkml.kernel.org/r/20161209182912.2726-6-bp@alien8.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
| * x86/idle: Remove enter_idle(), exit_idle()Len Brown2016-11-181-2/+0
| | | | | | | | | | | | | | | | | | | | | | Upon removal of the is_idle flag, these routines became NOPs. Signed-off-by: Len Brown <len.brown@intel.com> Acked-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: http://lkml.kernel.org/r/822f2c22cc5890f7b8ea0eeec60277eb44505b4e.1479449716.git.len.brown@intel.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | Merge branch 'x86-apic-for-linus' of ↵Linus Torvalds2016-12-121-2/+2
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 apic updates from Ingo Molnar: "Misc changes: - optimize (reduce) IRQ handler tracing overhead (Wanpeng Li) - clean up MSR helpers (Borislav Petkov) - fix build warning on some configs (Sebastian Andrzej Siewior)" * 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/msr: Cleanup/streamline MSR helpers x86/apic: Prevent tracing on apic_msr_write_eoi() x86/msr: Add wrmsr_notrace() x86/apic: Get rid of "warning: 'acpi_ioapic_lock' defined but not used"
| * | x86/apic: Prevent tracing on apic_msr_write_eoi()Wanpeng Li2016-11-091-2/+2
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 <peterz@infradead.org> Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Cc: kvm@vger.kernel.org Cc: Mike Galbraith <efault@gmx.de> Cc: Borislav Petkov <bp@alien8.de> Link: http://lkml.kernel.org/r/1478488420-5982-3-git-send-email-wanpeng.li@hotmail.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | x86/paravirt: Optimize native pv_lock_ops.vcpu_is_preempted()Peter Zijlstra2016-11-221-12/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Avoid the pointless function call to pv_lock_ops.vcpu_is_preempted() when a paravirt spinlock enabled kernel is ran on native hardware. Do this by patching out the CALL instruction with "XOR %RAX,%RAX" which has the same effect (0 return value). Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: David.Laight@ACULAB.COM Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: benh@kernel.crashing.org Cc: boqun.feng@gmail.com Cc: borntraeger@de.ibm.com Cc: bsingharora@gmail.com Cc: dave@stgolabs.net Cc: jgross@suse.com Cc: kernellwp@gmail.com Cc: konrad.wilk@oracle.com Cc: mpe@ellerman.id.au Cc: paulmck@linux.vnet.ibm.com Cc: paulus@samba.org Cc: pbonzini@redhat.com Cc: rkrcmar@redhat.com Cc: will.deacon@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | x86/kvm: Support the vCPU preemption checkPan Xinhui2016-11-221-0/+12
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Support the vcpu_is_preempted() functionality under KVM. This will enhance lock performance on overcommitted hosts (more runnable vCPUs than physical CPUs in the system) as doing busy waits for preempted vCPUs will hurt system performance far worse than early yielding. struct kvm_steal_time::preempted indicates that if one vCPU is running or not after commit "x86, kvm/x86.c: support vCPU preempted check". unix benchmark result: host: kernel 4.8.1, i5-4570, 4 cpus guest: kernel 4.8.1, 8 vcpus test-case after-patch before-patch Execl Throughput | 18307.9 lps | 11701.6 lps File Copy 1024 bufsize 2000 maxblocks | 1352407.3 KBps | 790418.9 KBps File Copy 256 bufsize 500 maxblocks | 367555.6 KBps | 222867.7 KBps File Copy 4096 bufsize 8000 maxblocks | 3675649.7 KBps | 1780614.4 KBps Pipe Throughput | 11872208.7 lps | 11855628.9 lps Pipe-based Context Switching | 1495126.5 lps | 1490533.9 lps Process Creation | 29881.2 lps | 28572.8 lps Shell Scripts (1 concurrent) | 23224.3 lpm | 22607.4 lpm Shell Scripts (8 concurrent) | 3531.4 lpm | 3211.9 lpm System Call Overhead | 10385653.0 lps | 10419979.0 lps Signed-off-by: Pan Xinhui <xinhui.pan@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Cc: David.Laight@ACULAB.COM Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: benh@kernel.crashing.org Cc: boqun.feng@gmail.com Cc: borntraeger@de.ibm.com Cc: bsingharora@gmail.com Cc: dave@stgolabs.net Cc: jgross@suse.com Cc: kernellwp@gmail.com Cc: konrad.wilk@oracle.com Cc: linuxppc-dev@lists.ozlabs.org Cc: mpe@ellerman.id.au Cc: paulmck@linux.vnet.ibm.com Cc: paulus@samba.org Cc: rkrcmar@redhat.com Cc: virtualization@lists.linux-foundation.org Cc: will.deacon@arm.com Cc: xen-devel-request@lists.xenproject.org Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/1478077718-37424-10-git-send-email-xinhui.pan@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* Merge branch 'smp-hotplug-for-linus' of ↵Linus Torvalds2016-10-031-27/+16
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull CPU hotplug updates from Thomas Gleixner: "Yet another batch of cpu hotplug core updates and conversions: - Provide core infrastructure for multi instance drivers so the drivers do not have to keep custom lists. - Convert custom lists to the new infrastructure. The block-mq custom list conversion comes through the block tree and makes the diffstat tip over to more lines removed than added. - Handle unbalanced hotplug enable/disable calls more gracefully. - Remove the obsolete CPU_STARTING/DYING notifier support. - Convert another batch of notifier users. The relayfs changes which conflicted with the conversion have been shipped to me by Andrew. The remaining lot is targeted for 4.10 so that we finally can remove the rest of the notifiers" * 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (46 commits) cpufreq: Fix up conversion to hotplug state machine blk/mq: Reserve hotplug states for block multiqueue x86/apic/uv: Convert to hotplug state machine s390/mm/pfault: Convert to hotplug state machine mips/loongson/smp: Convert to hotplug state machine mips/octeon/smp: Convert to hotplug state machine fault-injection/cpu: Convert to hotplug state machine padata: Convert to hotplug state machine cpufreq: Convert to hotplug state machine ACPI/processor: Convert to hotplug state machine virtio scsi: Convert to hotplug state machine oprofile/timer: Convert to hotplug state machine block/softirq: Convert to hotplug state machine lib/irq_poll: Convert to hotplug state machine x86/microcode: Convert to hotplug state machine sh/SH-X3 SMP: Convert to hotplug state machine ia64/mca: Convert to hotplug state machine ARM/OMAP/wakeupgen: Convert to hotplug state machine ARM/shmobile: Convert to hotplug state machine arm64/FP/SIMD: Convert to hotplug state machine ...
| * x86/kvm: Convert to hotplug state machineSebastian Andrzej Siewior2016-09-061-27/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Install the callbacks via the state machine. The online & down callbacks are invoked on the target CPU so we can avoid using smp_call_function_single(). local_irq_disable() is used because smp_call_function_single() used to invoke the function with interrupts disabled. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Cc: kvm@vger.kernel.org Cc: Peter Zijlstra <peterz@infradead.org> Cc: Gleb Natapov <gleb@kernel.org> Cc: rt@linutronix.de Link: http://lkml.kernel.org/r/20160818125731.27256-15-bigeasy@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | x86, locking/spinlocks: Remove ticket (spin)lock implementationPeter Zijlstra2016-09-301-245/+0
|/ | | | | | | | | | | | | | | | | | | | | We've unconditionally used the queued spinlock for many releases now. Its time to remove the old ticket lock code. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Waiman Long <waiman.long@hpe.com> Cc: Waiman.Long@hpe.com Cc: david.vrabel@citrix.com Cc: dhowells@redhat.com Cc: pbonzini@redhat.com Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/20160518184302.GO3193@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
* Merge branch 'x86-headers-for-linus' of ↵Linus Torvalds2016-08-011-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 header cleanups from Ingo Molnar: "This tree is a cleanup of the x86 tree reducing spurious uses of module.h - which should improve build performance a bit" * 'x86-headers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86, crypto: Restore MODULE_LICENSE() to glue_helper.c so it loads x86/apic: Remove duplicated include from probe_64.c x86/ce4100: Remove duplicated include from ce4100.c x86/headers: Include spinlock_types.h in x8664_ksyms_64.c for missing spinlock_t x86/platform: Delete extraneous MODULE_* tags fromm ts5500 x86: Audit and remove any remaining unnecessary uses of module.h x86/kvm: Audit and remove any unnecessary uses of module.h x86/xen: Audit and remove any unnecessary uses of module.h x86/platform: Audit and remove any unnecessary uses of module.h x86/lib: Audit and remove any unnecessary uses of module.h x86/kernel: Audit and remove any unnecessary uses of module.h x86/mm: Audit and remove any unnecessary uses of module.h x86: Don't use module.h just for AUTHOR / LICENSE tags
| * x86/kernel: Audit and remove any unnecessary uses of module.hPaul Gortmaker2016-07-141-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Historically a lot of these existed because we did not have a distinction between what was modular code and what was providing support to modules via EXPORT_SYMBOL and friends. That changed when we forked out support for the latter into the export.h file. This means we should be able to reduce the usage of module.h in code that is obj-y Makefile or bool Kconfig. The advantage in doing so is that module.h itself sources about 15 other headers; adding significantly to what we feed cpp, and it can obscure what headers we are effectively using. Since module.h was the source for init.h (for __init) and for export.h (for EXPORT_SYMBOL) we consider each obj-y/bool instance for the presence of either and replace as needed. Build testing revealed some implicit header usage that was fixed up accordingly. Note that some bool/obj-y instances remain since module.h is the header for some exception table entry stuff, and for things like __init_or_module (code that is tossed when MODULES=n). Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.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/20160714001901.31603-4-paul.gortmaker@windriver.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | KVM: Fix steal clock warp during guest CPU hotplugWanpeng Li2016-06-141-2/+0
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Sometimes, after CPU hotplug you can observe a spike in stolen time (100%) followed by the CPU being marked as 100% idle when it's actually busy with a CPU hog task. The trace looks like the following: cpuhp/1-12 [001] d.h1 167.461657: account_process_tick: steal = 1291385514, prev_steal_time = 0 cpuhp/1-12 [001] d.h1 167.461659: account_process_tick: steal_jiffies = 1291 <idle>-0 [001] d.h1 167.462663: account_process_tick: steal = 18732255, prev_steal_time = 1291000000 <idle>-0 [001] d.h1 167.462664: account_process_tick: steal_jiffies = 18446744072437 The sudden decrease of "steal" causes steal_jiffies to underflow. The root cause is kvm_steal_time being reset to 0 after hot-plugging back in a CPU. Instead, the preexisting value can be used, which is what the core scheduler code expects. John Stultz also reported a similar issue after guest S3. Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Wanpeng Li <wanpeng.li@hotmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: John Stultz <john.stultz@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1465813966-3116-2-git-send-email-wanpeng.li@hotmail.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* Merge branch 'x86-boot-for-linus' of ↵Linus Torvalds2016-05-161-8/+0
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 boot updates from Ingo Molnar: "The biggest changes in this cycle were: - prepare for more KASLR related changes, by restructuring, cleaning up and fixing the existing boot code. (Kees Cook, Baoquan He, Yinghai Lu) - simplifly/concentrate subarch handling code, eliminate paravirt_enabled() usage. (Luis R Rodriguez)" * 'x86-boot-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (50 commits) x86/KASLR: Clarify purpose of each get_random_long() x86/KASLR: Add virtual address choosing function x86/KASLR: Return earliest overlap when avoiding regions x86/KASLR: Add 'struct slot_area' to manage random_addr slots x86/boot: Add missing file header comments x86/KASLR: Initialize mapping_info every time x86/boot: Comment what finalize_identity_maps() does x86/KASLR: Build identity mappings on demand x86/boot: Split out kernel_ident_mapping_init() x86/boot: Clean up indenting for asm/boot.h x86/KASLR: Improve comments around the mem_avoid[] logic x86/boot: Simplify pointer casting in choose_random_location() x86/KASLR: Consolidate mem_avoid[] entries x86/boot: Clean up pointer casting x86/boot: Warn on future overlapping memcpy() use x86/boot: Extract error reporting functions x86/boot: Correctly bounds-check relocations x86/KASLR: Clean up unused code from old 'run_size' and rename it to 'kernel_total_size' x86/boot: Fix "run_size" calculation x86/boot: Calculate decompression size during boot not build ...
| * x86/paravirt: Remove paravirt_enabled()Luis R. Rodriguez2016-04-221-8/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that all previous paravirt_enabled() uses were replaced with proper x86 semantics by the previous patches we can remove the unused paravirt_enabled() mechanism. Signed-off-by: Luis R. Rodriguez <mcgrof@kernel.org> Acked-by: Juergen Gross <jgross@suse.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: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: andrew.cooper3@citrix.com Cc: andriy.shevchenko@linux.intel.com Cc: bigeasy@linutronix.de Cc: boris.ostrovsky@oracle.com Cc: david.vrabel@citrix.com Cc: ffainelli@freebox.fr Cc: george.dunlap@citrix.com Cc: glin@suse.com Cc: jlee@suse.com Cc: josh@joshtriplett.org Cc: julien.grall@linaro.org Cc: konrad.wilk@oracle.com Cc: kozerkov@parallels.com Cc: lenb@kernel.org Cc: lguest@lists.ozlabs.org Cc: linux-acpi@vger.kernel.org Cc: lv.zheng@intel.com Cc: matt@codeblueprint.co.uk Cc: mbizon@freebox.fr Cc: rjw@rjwysocki.net Cc: robert.moore@intel.com Cc: rusty@rustcorp.com.au Cc: tiwai@suse.de Cc: toshi.kani@hp.com Cc: xen-devel@lists.xensource.com Link: http://lkml.kernel.org/r/1460592286-300-15-git-send-email-mcgrof@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | x86/cpufeature: Remove cpu_has_hypervisorBorislav Petkov2016-03-311-1/+1
|/ | | | | | | | | | | | | | Use boot_cpu_has() instead. Tested-by: David Kershner <david.kershner@unisys.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: sparmaintainer@unisys.com Cc: virtualization@lists.linux-foundation.org Link: http://lkml.kernel.org/r/1459266123-21878-3-git-send-email-bp@alien8.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
* kvm, rt: change async pagefault code locking for PREEMPT_RTRik van Riel2016-03-221-18/+19
| | | | | | | | | | The async pagefault wake code can run from the idle task in exception context, so everything here needs to be made non-preemptible. Conversion to a simple wait queue and raw spinlock does the trick. Signed-off-by: Rik van Riel <riel@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2015-06-241-2/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull first batch of KVM updates from Paolo Bonzini: "The bulk of the changes here is for x86. And for once it's not for silicon that no one owns: these are really new features for everyone. Details: - ARM: several features are in progress but missed the 4.2 deadline. So here is just a smattering of bug fixes, plus enabling the VFIO integration. - s390: Some fixes/refactorings/optimizations, plus support for 2GB pages. - x86: * host and guest support for marking kvmclock as a stable scheduler clock. * support for write combining. * support for system management mode, needed for secure boot in guests. * a bunch of cleanups required for the above * support for virtualized performance counters on AMD * legacy PCI device assignment is deprecated and defaults to "n" in Kconfig; VFIO replaces it On top of this there are also bug fixes and eager FPU context loading for FPU-heavy guests. - Common code: Support for multiple address spaces; for now it is used only for x86 SMM but the s390 folks also have plans" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (124 commits) KVM: s390: clear floating interrupt bitmap and parameters KVM: x86/vPMU: Enable PMU handling for AMD PERFCTRn and EVNTSELn MSRs KVM: x86/vPMU: Implement AMD vPMU code for KVM KVM: x86/vPMU: Define kvm_pmu_ops to support vPMU function dispatch KVM: x86/vPMU: introduce kvm_pmu_msr_idx_to_pmc KVM: x86/vPMU: reorder PMU functions KVM: x86/vPMU: whitespace and stylistic adjustments in PMU code KVM: x86/vPMU: use the new macros to go between PMC, PMU and VCPU KVM: x86/vPMU: introduce pmu.h header KVM: x86/vPMU: rename a few PMU functions KVM: MTRR: do not map huge page for non-consistent range KVM: MTRR: simplify kvm_mtrr_get_guest_memory_type KVM: MTRR: introduce mtrr_for_each_mem_type KVM: MTRR: introduce fixed_mtrr_addr_* functions KVM: MTRR: sort variable MTRRs KVM: MTRR: introduce var_mtrr_range KVM: MTRR: introduce fixed_mtrr_segment table KVM: MTRR: improve kvm_mtrr_get_guest_memory_type KVM: MTRR: do not split 64 bits MSR content KVM: MTRR: clean up mtrr default type ...
| * kvm: x86: Make functions that have no external callers staticNicholas Krause2015-05-201-2/+2
| | | | | | | | | | | | | | | | | | This makes the functions kvm_guest_cpu_init and kvm_init_debugfs static now due to having no external callers outside their declarations in the file, kvm.c. Signed-off-by: Nicholas Krause <xerofoify@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | locking/pvqspinlock: Rename QUEUED_SPINLOCK to QUEUED_SPINLOCKSIngo Molnar2015-05-111-5/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Valentin Rothberg reported that we use CONFIG_QUEUED_SPINLOCKS in arch/x86/kernel/paravirt_patch_32.c, while the symbol is called CONFIG_QUEUED_SPINLOCK. (Note the extra 'S') But the typo was natural: the proper English term for such a generic object would be 'queued spinlocks' - so rename this and related symbols accordingly to the plural form. Reported-by: Valentin Rothberg <valentinrothberg@gmail.com> Cc: Douglas Hatch <doug.hatch@hp.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Scott J Norton <scott.norton@hp.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Waiman Long <Waiman.Long@hp.com> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | locking/pvqspinlock, x86: Enable PV qspinlock for KVMWaiman Long2015-05-081-0/+43
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds the necessary KVM specific code to allow KVM to support the CPU halting and kicking operations needed by the queue spinlock PV code. Signed-off-by: Waiman Long <Waiman.Long@hp.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Daniel J Blueman <daniel@numascale.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Douglas Hatch <doug.hatch@hp.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Paolo Bonzini <paolo.bonzini@gmail.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Cc: Rik van Riel <riel@redhat.com> Cc: Scott J Norton <scott.norton@hp.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: virtualization@lists.linux-foundation.org Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/1429901803-29771-11-git-send-email-Waiman.Long@hp.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* watchdog: introduce the hardlockup_detector_disable() functionUlrich Obergfell2015-04-141-1/+1
| | | | | | | | | | | | | | Have kvm_guest_init() use hardlockup_detector_disable() instead of watchdog_enable_hardlockup_detector(false). Remove the watchdog_hardlockup_detector_is_enabled() and the watchdog_enable_hardlockup_detector() function which are no longer needed. Signed-off-by: Ulrich Obergfell <uobergfe@redhat.com> Signed-off-by: Don Zickus <dzickus@redhat.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* x86/spinlocks/paravirt: Fix memory corruption on unlockRaghavendra K T2015-02-181-4/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Paravirt spinlock clears slowpath flag after doing unlock. As explained by Linus currently it does: prev = *lock; add_smp(&lock->tickets.head, TICKET_LOCK_INC); /* add_smp() is a full mb() */ if (unlikely(lock->tickets.tail & TICKET_SLOWPATH_FLAG)) __ticket_unlock_slowpath(lock, prev); which is *exactly* the kind of things you cannot do with spinlocks, because after you've done the "add_smp()" and released the spinlock for the fast-path, you can't access the spinlock any more. Exactly because a fast-path lock might come in, and release the whole data structure. Linus suggested that we should not do any writes to lock after unlock(), and we can move slowpath clearing to fastpath lock. So this patch implements the fix with: 1. Moving slowpath flag to head (Oleg): Unlocked locks don't care about the slowpath flag; therefore we can keep it set after the last unlock, and clear it again on the first (try)lock. -- this removes the write after unlock. note that keeping slowpath flag would result in unnecessary kicks. By moving the slowpath flag from the tail to the head ticket we also avoid the need to access both the head and tail tickets on unlock. 2. use xadd to avoid read/write after unlock that checks the need for unlock_kick (Linus): We further avoid the need for a read-after-release by using xadd; the prev head value will include the slowpath flag and indicate if we need to do PV kicking of suspended spinners -- on modern chips xadd isn't (much) more expensive than an add + load. Result: setup: 16core (32 cpu +ht sandy bridge 8GB 16vcpu guest) benchmark overcommit %improve kernbench 1x -0.13 kernbench 2x 0.02 dbench 1x -1.77 dbench 2x -0.63 [Jeremy: Hinted missing TICKET_LOCK_INC for kick] [Oleg: Moved slowpath flag to head, ticket_equals idea] [PeterZ: Added detailed changelog] Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Reported-by: Sasha Levin <sasha.levin@oracle.com> Tested-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Cc: Andrew Jones <drjones@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Christoph Lameter <cl@linux.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dave Jones <davej@redhat.com> Cc: David Vrabel <david.vrabel@citrix.com> Cc: Fernando Luis Vázquez Cao <fernando_b1@lab.ntt.co.jp> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Ulrich Obergfell <uobergfe@redhat.com> Cc: Waiman Long <Waiman.Long@hp.com> Cc: a.ryabinin@samsung.com Cc: dave@stgolabs.net Cc: hpa@zytor.com Cc: jasowang@redhat.com Cc: jeremy@goop.org Cc: paul.gortmaker@windriver.com Cc: riel@redhat.com Cc: tglx@linutronix.de Cc: waiman.long@hp.com Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/20150215173043.GA7471@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* x86, kvm: Clear paravirt_enabled on KVM guests for espfix32's benefitAndy Lutomirski2014-12-101-1/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | paravirt_enabled has the following effects: - Disables the F00F bug workaround warning. There is no F00F bug workaround any more because Linux's standard IDT handling already works around the F00F bug, but the warning still exists. This is only cosmetic, and, in any event, there is no such thing as KVM on a CPU with the F00F bug. - Disables 32-bit APM BIOS detection. On a KVM paravirt system, there should be no APM BIOS anyway. - Disables tboot. I think that the tboot code should check the CPUID hypervisor bit directly if it matters. - paravirt_enabled disables espfix32. espfix32 should *not* be disabled under KVM paravirt. The last point is the purpose of this patch. It fixes a leak of the high 16 bits of the kernel stack address on 32-bit KVM paravirt guests. Fixes CVE-2014-8134. Cc: stable@vger.kernel.org Suggested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* Merge branch 'for-3.18-consistent-ops' of ↵Linus Torvalds2014-10-151-11/+11
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu Pull percpu consistent-ops changes from Tejun Heo: "Way back, before the current percpu allocator was implemented, static and dynamic percpu memory areas were allocated and handled separately and had their own accessors. The distinction has been gone for many years now; however, the now duplicate two sets of accessors remained with the pointer based ones - this_cpu_*() - evolving various other operations over time. During the process, we also accumulated other inconsistent operations. This pull request contains Christoph's patches to clean up the duplicate accessor situation. __get_cpu_var() uses are replaced with with this_cpu_ptr() and __this_cpu_ptr() with raw_cpu_ptr(). Unfortunately, the former sometimes is tricky thanks to C being a bit messy with the distinction between lvalues and pointers, which led to a rather ugly solution for cpumask_var_t involving the introduction of this_cpu_cpumask_var_ptr(). This converts most of the uses but not all. Christoph will follow up with the remaining conversions in this merge window and hopefully remove the obsolete accessors" * 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (38 commits) irqchip: Properly fetch the per cpu offset percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t -fix ia64: sn_nodepda cannot be assigned to after this_cpu conversion. Use __this_cpu_write. percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t Revert "powerpc: Replace __get_cpu_var uses" percpu: Remove __this_cpu_ptr clocksource: Replace __this_cpu_ptr with raw_cpu_ptr sparc: Replace __get_cpu_var uses avr32: Replace __get_cpu_var with __this_cpu_write blackfin: Replace __get_cpu_var uses tile: Use this_cpu_ptr() for hardware counters tile: Replace __get_cpu_var uses powerpc: Replace __get_cpu_var uses alpha: Replace __get_cpu_var ia64: Replace __get_cpu_var uses s390: cio driver &__get_cpu_var replacements s390: Replace __get_cpu_var uses mips: Replace __get_cpu_var uses MIPS: Replace __get_cpu_var uses in FPU emulator. arm: Replace __this_cpu_ptr with raw_cpu_ptr ...
| * x86: Replace __get_cpu_var usesChristoph Lameter2014-08-261-11/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | __get_cpu_var() is used for multiple purposes in the kernel source. One of them is address calculation via the form &__get_cpu_var(x). This calculates the address for the instance of the percpu variable of the current processor based on an offset. Other use cases are for storing and retrieving data from the current processors percpu area. __get_cpu_var() can be used as an lvalue when writing data or on the right side of an assignment. __get_cpu_var() is defined as : #define __get_cpu_var(var) (*this_cpu_ptr(&(var))) __get_cpu_var() always only does an address determination. However, store and retrieve operations could use a segment prefix (or global register on other platforms) to avoid the address calculation. this_cpu_write() and this_cpu_read() can directly take an offset into a percpu area and use optimized assembly code to read and write per cpu variables. This patch converts __get_cpu_var into either an explicit address calculation using this_cpu_ptr() or into a use of this_cpu operations that use the offset. Thereby address calculations are avoided and less registers are used when code is generated. Transformations done to __get_cpu_var() 1. Determine the address of the percpu instance of the current processor. DEFINE_PER_CPU(int, y); int *x = &__get_cpu_var(y); Converts to int *x = this_cpu_ptr(&y); 2. Same as #1 but this time an array structure is involved. DEFINE_PER_CPU(int, y[20]); int *x = __get_cpu_var(y); Converts to int *x = this_cpu_ptr(y); 3. Retrieve the content of the current processors instance of a per cpu variable. DEFINE_PER_CPU(int, y); int x = __get_cpu_var(y) Converts to int x = __this_cpu_read(y); 4. Retrieve the content of a percpu struct DEFINE_PER_CPU(struct mystruct, y); struct mystruct x = __get_cpu_var(y); Converts to memcpy(&x, this_cpu_ptr(&y), sizeof(x)); 5. Assignment to a per cpu variable DEFINE_PER_CPU(int, y) __get_cpu_var(y) = x; Converts to __this_cpu_write(y, x); 6. Increment/Decrement etc of a per cpu variable DEFINE_PER_CPU(int, y); __get_cpu_var(y)++ Converts to __this_cpu_inc(y) Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86@kernel.org Acked-by: H. Peter Anvin <hpa@linux.intel.com> Acked-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Christoph Lameter <cl@linux.com> Signed-off-by: Tejun Heo <tj@kernel.org>
* | kvm: ensure hard lockup detection is disabled by defaultUlrich Obergfell2014-10-141-0/+8
|/ | | | | | | | | | | | | Use watchdog_enable_hardlockup_detector() to set hard lockup detection's default value to false. It's risky to run this detection in a guest, as false positives are easy to trigger, especially if the host is overcommitted. Signed-off-by: Ulrich Obergfell <uobergfe@redhat.com> Signed-off-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Don Zickus <dzickus@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'perf-core-for-linus' of ↵Linus Torvalds2014-06-121-1/+3
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull more perf updates from Ingo Molnar: "A second round of perf updates: - wide reaching kprobes sanitization and robustization, with the hope of fixing all 'probe this function crashes the kernel' bugs, by Masami Hiramatsu. - uprobes updates from Oleg Nesterov: tmpfs support, corner case fixes and robustization work. - perf tooling updates and fixes from Jiri Olsa, Namhyung Ki, Arnaldo et al: * Add support to accumulate hist periods (Namhyung Kim) * various fixes, refactorings and enhancements" * 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (101 commits) perf: Differentiate exec() and non-exec() comm events perf: Fix perf_event_comm() vs. exec() assumption uprobes/x86: Rename arch_uprobe->def to ->defparam, minor comment updates perf/documentation: Add description for conditional branch filter perf/x86: Add conditional branch filtering support perf/tool: Add conditional branch filter 'cond' to perf record perf: Add new conditional branch filter 'PERF_SAMPLE_BRANCH_COND' uprobes: Teach copy_insn() to support tmpfs uprobes: Shift ->readpage check from __copy_insn() to uprobe_register() perf/x86: Use common PMU interrupt disabled code perf/ARM: Use common PMU interrupt disabled code perf: Disable sampled events if no PMU interrupt perf: Fix use after free in perf_remove_from_context() perf tools: Fix 'make help' message error perf record: Fix poll return value propagation perf tools: Move elide bool into perf_hpp_fmt struct perf tools: Remove elide setup for SORT_MODE__MEMORY mode perf tools: Fix "==" into "=" in ui_browser__warning assignment perf tools: Allow overriding sysfs and proc finding with env var perf tools: Consider header files outside perf directory in tags target ...
| * kprobes, x86: Use NOKPROBE_SYMBOL() instead of __kprobes annotationMasami Hiramatsu2014-04-241-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use NOKPROBE_SYMBOL macro for protecting functions from kprobes instead of __kprobes annotation under arch/x86. This applies nokprobe_inline annotation for some cases, because NOKPROBE_SYMBOL() will inhibit inlining by referring the symbol address. This just folds a bunch of previous NOKPROBE_SYMBOL() cleanup patches for x86 to one patch. Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Link: http://lkml.kernel.org/r/20140417081814.26341.51656.stgit@ltc230.yrl.intra.hitachi.co.jp Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Borislav Petkov <bp@suse.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Fernando Luis Vázquez Cao <fernando_b1@lab.ntt.co.jp> Cc: Gleb Natapov <gleb@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Jonathan Lebon <jlebon@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Matt Fleming <matt.fleming@intel.com> Cc: Michel Lespinasse <walken@google.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Seiji Aguchi <seiji.aguchi@hds.com> Cc: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com> Cc: Tejun Heo <tj@kernel.org> Cc: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | x86: fix page fault tracing when KVM guest support enabledDave Hansen2014-05-221-1/+1
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I noticed on some of my systems that page fault tracing doesn't work: cd /sys/kernel/debug/tracing echo 1 > events/exceptions/enable cat trace; # nothing shows up I eventually traced it down to CONFIG_KVM_GUEST. At least in a KVM VM, enabling that option breaks page fault tracing, and disabling fixes it. I tried on some old kernels and this does not appear to be a regression: it never worked. There are two page-fault entry functions today. One when tracing is on and another when it is off. The KVM code calls do_page_fault() directly instead of calling the traced version: > dotraplinkage void __kprobes > do_async_page_fault(struct pt_regs *regs, unsigned long > error_code) > { > enum ctx_state prev_state; > > switch (kvm_read_and_reset_pf_reason()) { > default: > do_page_fault(regs, error_code); > break; > case KVM_PV_REASON_PAGE_NOT_PRESENT: I'm also having problems with the page fault tracing on bare metal (same symptom of no trace output). I'm unsure if it's related. Steven had an alternative to this which has zero overhead when tracing is off where this includes the standard noops even when tracing is disabled. I'm unconvinced that the extra complexity of his apporach: http://lkml.kernel.org/r/20140508194508.561ed220@gandalf.local.home is worth it, expecially considering that the KVM code is already making page fault entry slower here. This solution is dirt-simple. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86@kernel.org Cc: Peter Zijlstra <peterz@infradead.org> Cc: Gleb Natapov <gleb@redhat.com> Cc: kvm@vger.kernel.org Cc: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: "H. Peter Anvin" <hpa@zytor.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* kvm: remove redundant registration of BSP's hv_clock areaFernando Luis Vázquez Cao2014-02-221-1/+0
| | | | | | | | | | | These days hv_clock allocation is memblock based (i.e. the percpu allocator is not involved), which means that the physical address of each of the per-cpu hv_clock areas is guaranteed to remain unchanged through all its lifetime and we do not need to update its location after CPU bring-up. Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds2014-01-311-0/+32
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull more KVM updates from Paolo Bonzini: "Second batch of KVM updates. Some minor x86 fixes, two s390 guest features that need some handling in the host, and all the PPC changes. The PPC changes include support for little-endian guests and enablement for new POWER8 features" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (45 commits) x86, kvm: correctly access the KVM_CPUID_FEATURES leaf at 0x40000101 x86, kvm: cache the base of the KVM cpuid leaves kvm: x86: move KVM_CAP_HYPERV_TIME outside #ifdef KVM: PPC: Book3S PR: Cope with doorbell interrupts KVM: PPC: Book3S HV: Add software abort codes for transactional memory KVM: PPC: Book3S HV: Add new state for transactional memory powerpc/Kconfig: Make TM select VSX and VMX KVM: PPC: Book3S HV: Basic little-endian guest support KVM: PPC: Book3S HV: Add support for DABRX register on POWER7 KVM: PPC: Book3S HV: Prepare for host using hypervisor doorbells KVM: PPC: Book3S HV: Handle new LPCR bits on POWER8 KVM: PPC: Book3S HV: Handle guest using doorbells for IPIs KVM: PPC: Book3S HV: Consolidate code that checks reason for wake from nap KVM: PPC: Book3S HV: Implement architecture compatibility modes for POWER8 KVM: PPC: Book3S HV: Add handler for HV facility unavailable KVM: PPC: Book3S HV: Flush the correct number of TLB sets on POWER8 KVM: PPC: Book3S HV: Context-switch new POWER8 SPRs KVM: PPC: Book3S HV: Align physical and virtual CPU thread numbers KVM: PPC: Book3S HV: Don't set DABR on POWER8 kvm/ppc: IRQ disabling cleanup ...
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