pm24.git/arch/x86, branch v4.9

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

2016-12-07T19:39:27Z

Pull x86 fixes from Ingo Molnar: "Misc fixes: a core dumping crash fix, a guess-unwinder regression fix, plus three build warning fixes" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/unwind: Fix guess-unwinder regression x86/build: Annotate die() with noreturn to fix build warning on clang x86/platform/olpc: Fix resume handler build warning x86/apic/uv: Silence a shift wrapping warning x86/coredump: Always use user_regs_struct for compat_elf_gregset_t

perf/x86: Fix full width counter, counter overflow

2016-12-06T08:44:28Z

Lukasz reported that perf stat counters overflow handling is broken on KNL/SLM. Both these parts have full_width_write set, and that does indeed have a problem. In order to deal with counter wrap, we must sample the counter at at least half the counter period (see also the sampling theorem) such that we can unambiguously reconstruct the count. However commit: 069e0c3c4058 ("perf/x86/intel: Support full width counting") sets the sampling interval to the full period, not half. Fixing that exposes another issue, in that we must not sign extend the delta value when we shift it right; the counter cannot have decremented after all. With both these issues fixed, counter overflow functions correctly again. Reported-by: Lukasz Odzioba Tested-by: Liang, Kan Tested-by: Odzioba, Lukasz Signed-off-by: Peter Zijlstra (Intel) Cc: Alexander Shishkin Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Thomas Gleixner Cc: Vince Weaver Cc: stable@vger.kernel.org Fixes: 069e0c3c4058 ("perf/x86/intel: Support full width counting") Signed-off-by: Ingo Molnar

perf/x86/intel: Enable C-state residency events for Knights Mill

2016-12-06T08:44:27Z

The Knights Mill is enough close to Knights Landing so the path reuses C-state residency support of the latter. Signed-off-by: Piotr Luc Signed-off-by: Peter Zijlstra (Intel) Cc: Alexander Shishkin Cc: Arnaldo Carvalho de Melo Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Thomas Gleixner Cc: Vince Weaver Link: http://lkml.kernel.org/r/20161201000853.18260-1-piotr.luc@intel.com Signed-off-by: Ingo Molnar

x86/unwind: Fix guess-unwinder regression

2016-11-28T06:47:54Z

My attempt at fixing some KASAN false positive warnings was rather brain dead, and it broke the guess unwinder. With frame pointers disabled, /proc//stack is broken: # cat /proc/1/stack [] 0xffffffffffffffff Restore the code flow to more closely resemble its previous state, while still using READ_ONCE_NOCHECK() macros to silence KASAN false positives. Signed-off-by: Josh Poimboeuf Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Fixes: c2d75e03d630 ("x86/unwind: Prevent KASAN false positive warnings in guess unwinder") Link: http://lkml.kernel.org/r/b824f92c2c22eca5ec95ac56bd2a7c84cf0b9df9.1480309971.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar

x86/build: Annotate die() with noreturn to fix build warning on clang

2016-11-28T06:47:22Z

Fixes below warning with clang: In file included from ../arch/x86/tools/relocs_64.c:17: ../arch/x86/tools/relocs.c:977:6: warning: variable 'do_reloc' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized] Signed-off-by: Peter Foley Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/20161126222229.673-1-pefoley2@pefoley.com Signed-off-by: Ingo Molnar

x86/platform/olpc: Fix resume handler build warning

2016-11-28T06:46:03Z

Fix: arch/x86/platform/olpc/olpc-xo15-sci.c:199:12: warning: ‘xo15_sci_resume’ defined but not used [-Wunused-function] static int xo15_sci_resume(struct device *dev) ^ which I see in randconfig builds here. Signed-off-by: Borislav Petkov Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/20161126142706.13602-1-bp@alien8.de Signed-off-by: Ingo Molnar

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

2016-11-26T20:18:59Z

Pull KVM fixes from Radim Krčmář: "Four fixes for bugs found by syzkaller on x86, all for stable" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: x86: check for pic and ioapic presence before use KVM: x86: fix out-of-bounds accesses of rtc_eoi map KVM: x86: drop error recovery in em_jmp_far and em_ret_far KVM: x86: fix out-of-bounds access in lapic

KVM: x86: check for pic and ioapic presence before use

2016-11-24T17:39:28Z

Split irqchip allows pic and ioapic routes to be used without them being created, which results in NULL access. Check for NULL and avoid it. (The setup is too racy for a nicer solutions.) Found by syzkaller: general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: CPU: 3 PID: 11923 Comm: kworker/3:2 Not tainted 4.9.0-rc5+ #27 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 Workqueue: events irqfd_inject task: ffff88006a06c7c0 task.stack: ffff880068638000 RIP: 0010:[...] [...] __lock_acquire+0xb35/0x3380 kernel/locking/lockdep.c:3221 RSP: 0000:ffff88006863ea20 EFLAGS: 00010006 RAX: dffffc0000000000 RBX: dffffc0000000000 RCX: 0000000000000000 RDX: 0000000000000039 RSI: 0000000000000000 RDI: 1ffff1000d0c7d9e RBP: ffff88006863ef58 R08: 0000000000000001 R09: 0000000000000000 R10: 00000000000001c8 R11: 0000000000000000 R12: ffff88006a06c7c0 R13: 0000000000000001 R14: ffffffff8baab1a0 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff88006d100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000004abdd0 CR3: 000000003e2f2000 CR4: 00000000000026e0 Stack: ffffffff894d0098 1ffff1000d0c7d56 ffff88006863ecd0 dffffc0000000000 ffff88006a06c7c0 0000000000000000 ffff88006863ecf8 0000000000000082 0000000000000000 ffffffff815dd7c1 ffffffff00000000 ffffffff00000000 Call Trace: [...] lock_acquire+0x2a2/0x790 kernel/locking/lockdep.c:3746 [...] __raw_spin_lock include/linux/spinlock_api_smp.h:144 [...] _raw_spin_lock+0x38/0x50 kernel/locking/spinlock.c:151 [...] spin_lock include/linux/spinlock.h:302 [...] kvm_ioapic_set_irq+0x4c/0x100 arch/x86/kvm/ioapic.c:379 [...] kvm_set_ioapic_irq+0x8f/0xc0 arch/x86/kvm/irq_comm.c:52 [...] kvm_set_irq+0x239/0x640 arch/x86/kvm/../../../virt/kvm/irqchip.c:101 [...] irqfd_inject+0xb4/0x150 arch/x86/kvm/../../../virt/kvm/eventfd.c:60 [...] process_one_work+0xb40/0x1ba0 kernel/workqueue.c:2096 [...] worker_thread+0x214/0x18a0 kernel/workqueue.c:2230 [...] kthread+0x328/0x3e0 kernel/kthread.c:209 [...] ret_from_fork+0x2a/0x40 arch/x86/entry/entry_64.S:433 Reported-by: Dmitry Vyukov Cc: stable@vger.kernel.org Fixes: 49df6397edfc ("KVM: x86: Split the APIC from the rest of IRQCHIP.") Signed-off-by: Radim Krčmář

KVM: x86: fix out-of-bounds accesses of rtc_eoi map

2016-11-24T17:37:19Z

KVM was using arrays of size KVM_MAX_VCPUS with vcpu_id, but ID can be bigger that the maximal number of VCPUs, resulting in out-of-bounds access. Found by syzkaller: BUG: KASAN: slab-out-of-bounds in __apic_accept_irq+0xb33/0xb50 at addr [...] Write of size 1 by task a.out/27101 CPU: 1 PID: 27101 Comm: a.out Not tainted 4.9.0-rc5+ #49 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 [...] Call Trace: [...] __apic_accept_irq+0xb33/0xb50 arch/x86/kvm/lapic.c:905 [...] kvm_apic_set_irq+0x10e/0x180 arch/x86/kvm/lapic.c:495 [...] kvm_irq_delivery_to_apic+0x732/0xc10 arch/x86/kvm/irq_comm.c:86 [...] ioapic_service+0x41d/0x760 arch/x86/kvm/ioapic.c:360 [...] ioapic_set_irq+0x275/0x6c0 arch/x86/kvm/ioapic.c:222 [...] kvm_ioapic_inject_all arch/x86/kvm/ioapic.c:235 [...] kvm_set_ioapic+0x223/0x310 arch/x86/kvm/ioapic.c:670 [...] kvm_vm_ioctl_set_irqchip arch/x86/kvm/x86.c:3668 [...] kvm_arch_vm_ioctl+0x1a08/0x23c0 arch/x86/kvm/x86.c:3999 [...] kvm_vm_ioctl+0x1fa/0x1a70 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3099 Reported-by: Dmitry Vyukov Cc: stable@vger.kernel.org Fixes: af1bae5497b9 ("KVM: x86: bump KVM_MAX_VCPU_ID to 1023") Reviewed-by: Paolo Bonzini Reviewed-by: David Hildenbrand Signed-off-by: Radim Krčmář

KVM: x86: drop error recovery in em_jmp_far and em_ret_far

2016-11-24T17:36:54Z

em_jmp_far and em_ret_far assumed that setting IP can only fail in 64 bit mode, but syzkaller proved otherwise (and SDM agrees). Code segment was restored upon failure, but it was left uninitialized outside of long mode, which could lead to a leak of host kernel stack. We could have fixed that by always saving and restoring the CS, but we take a simpler approach and just break any guest that manages to fail as the error recovery is error-prone and modern CPUs don't need emulator for this. Found by syzkaller: WARNING: CPU: 2 PID: 3668 at arch/x86/kvm/emulate.c:2217 em_ret_far+0x428/0x480 Kernel panic - not syncing: panic_on_warn set ... CPU: 2 PID: 3668 Comm: syz-executor Not tainted 4.9.0-rc4+ #49 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011 [...] Call Trace: [...] __dump_stack lib/dump_stack.c:15 [...] dump_stack+0xb3/0x118 lib/dump_stack.c:51 [...] panic+0x1b7/0x3a3 kernel/panic.c:179 [...] __warn+0x1c4/0x1e0 kernel/panic.c:542 [...] warn_slowpath_null+0x2c/0x40 kernel/panic.c:585 [...] em_ret_far+0x428/0x480 arch/x86/kvm/emulate.c:2217 [...] em_ret_far_imm+0x17/0x70 arch/x86/kvm/emulate.c:2227 [...] x86_emulate_insn+0x87a/0x3730 arch/x86/kvm/emulate.c:5294 [...] x86_emulate_instruction+0x520/0x1ba0 arch/x86/kvm/x86.c:5545 [...] emulate_instruction arch/x86/include/asm/kvm_host.h:1116 [...] complete_emulated_io arch/x86/kvm/x86.c:6870 [...] complete_emulated_mmio+0x4e9/0x710 arch/x86/kvm/x86.c:6934 [...] kvm_arch_vcpu_ioctl_run+0x3b7a/0x5a90 arch/x86/kvm/x86.c:6978 [...] kvm_vcpu_ioctl+0x61e/0xdd0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2557 [...] vfs_ioctl fs/ioctl.c:43 [...] do_vfs_ioctl+0x18c/0x1040 fs/ioctl.c:679 [...] SYSC_ioctl fs/ioctl.c:694 [...] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:685 [...] entry_SYSCALL_64_fastpath+0x1f/0xc2 Reported-by: Dmitry Vyukov Cc: stable@vger.kernel.org Fixes: d1442d85cc30 ("KVM: x86: Handle errors when RIP is set during far jumps") Signed-off-by: Radim Krčmář