1. 12 12月, 2016 1 次提交
  2. 11 12月, 2016 2 次提交
  3. 09 12月, 2016 2 次提交
    • H
      parisc: Fix TLB related boot crash on SMP machines · 24d0492b
      Helge Deller 提交于
      At bootup we run measurements to calculate the best threshold for when we
      should be using full TLB flushes instead of just flushing a specific amount of
      TLB entries.  This performance test is run over the kernel text segment.
      
      But running this TLB performance test on the kernel text segment turned out to
      crash some SMP machines when the kernel text pages were mapped as huge pages.
      
      To avoid those crashes this patch simply skips this test on some SMP machines
      and calculates an optimal threshold based on the maximum number of available
      TLB entries and number of online CPUs.
      
      On a technical side, this seems to happen:
      The TLB measurement code uses flush_tlb_kernel_range() to flush specific TLB
      entries with a page size of 4k (pdtlb 0(sr1,addr)). On UP systems this purge
      instruction seems to work without problems even if the pages were mapped as
      huge pages.  But on SMP systems the TLB purge instruction is broadcasted to
      other CPUs. Those CPUs then crash the machine because the page size is not as
      expected.  C8000 machines with PA8800/PA8900 CPUs were not affected by this
      problem, because the required cache coherency prohibits to use huge pages at
      all.  Sadly I didn't found any documentation about this behaviour, so this
      finding is purely based on testing with phyiscal SMP machines (A500-44 and
      J5000, both were 2-way boxes).
      
      Cc: <stable@vger.kernel.org> # v3.18+
      Signed-off-by: NHelge Deller <deller@gmx.de>
      24d0492b
    • R
      ARM: dts: orion5x: fix number of sata port for linkstation ls-gl · 038ccb3e
      Roger Shimizu 提交于
      Bug report from Debian [0] shows there's minor changed model of
      Linkstation LS-GL that uses the 2nd SATA port of the SoC.
      So it's necessary to enable two SATA ports, though for that specific
      model only the 2nd one is used.
      
      [0] https://bugs.debian.org/845611
      
      Fixes: b1742ffa ("ARM: dts: orion5x: add device tree for buffalo linkstation ls-gl")
      Reported-by: NRyan Tandy <ryan@nardis.ca>
      Tested-by: NRyan Tandy <ryan@nardis.ca>
      Signed-off-by: NRoger Shimizu <rogershimizu@gmail.com>
      Signed-off-by: NGregory CLEMENT <gregory.clement@free-electrons.com>
      038ccb3e
  4. 08 12月, 2016 2 次提交
  5. 07 12月, 2016 2 次提交
    • J
      parisc: Remove unnecessary TLB purges from flush_dcache_page_asm and flush_icache_page_asm · febe4296
      John David Anglin 提交于
      We have four routines in pacache.S that use temporary alias pages:
      copy_user_page_asm(), clear_user_page_asm(), flush_dcache_page_asm() and
      flush_icache_page_asm().  copy_user_page_asm() and clear_user_page_asm()
      don't purge the TLB entry used for the operation.
      flush_dcache_page_asm() and flush_icache_page_asm do purge the entry.
      
      Presumably, this was thought to optimize TLB use.  However, the
      operation is quite heavy weight on PA 1.X processors as we need to take
      the TLB lock and a TLB broadcast is sent to all processors.
      
      This patch removes the purges from flush_dcache_page_asm() and
      flush_icache_page_asm.
      Signed-off-by: NJohn David Anglin  <dave.anglin@bell.net>
      Cc: <stable@vger.kernel.org> # v3.16+
      Signed-off-by: NHelge Deller <deller@gmx.de>
      febe4296
    • J
      parisc: Purge TLB before setting PTE · c78e710c
      John David Anglin 提交于
      The attached change interchanges the order of purging the TLB and
      setting the corresponding page table entry.  TLB purges are strongly
      ordered.  It occurred to me one night that setting the PTE first might
      have subtle ordering issues on SMP machines and cause random memory
      corruption.
      
      A TLB lock guards the insertion of user TLB entries.  So after the TLB
      is purged, a new entry can't be inserted until the lock is released.
      This ensures that the new PTE value is used when the lock is released.
      
      Since making this change, no random segmentation faults have been
      observed on the Debian hppa buildd servers.
      Signed-off-by: NJohn David Anglin  <dave.anglin@bell.net>
      Cc: <stable@vger.kernel.org> # v3.16+
      Signed-off-by: NHelge Deller <deller@gmx.de>
      c78e710c
  6. 06 12月, 2016 2 次提交
  7. 03 12月, 2016 1 次提交
  8. 01 12月, 2016 3 次提交
  9. 30 11月, 2016 1 次提交
  10. 29 11月, 2016 3 次提交
  11. 28 11月, 2016 4 次提交
  12. 25 11月, 2016 10 次提交
    • J
      parisc: Also flush data TLB in flush_icache_page_asm · 5035b230
      John David Anglin 提交于
      This is the second issue I noticed in reviewing the parisc TLB code.
      
      The fic instruction may use either the instruction or data TLB in
      flushing the instruction cache.  Thus, on machines with a split TLB, we
      should also flush the data TLB after setting up the temporary alias
      registers.
      
      Although this has no functional impact, I changed the pdtlb and pitlb
      instructions to consistently use the index register %r0.  These
      instructions do not support integer displacements.
      
      Tested on rp3440 and c8000.
      Signed-off-by: NJohn David Anglin  <dave.anglin@bell.net>
      Cc: <stable@vger.kernel.org> # v3.16+
      Signed-off-by: NHelge Deller <deller@gmx.de>
      5035b230
    • J
      parisc: Fix race in pci-dma.c · c0452fb9
      John David Anglin 提交于
      We are still troubled by occasional random segmentation faults and
      memory memory corruption on SMP machines.  The causes quite a few
      package builds to fail on the Debian buildd machines for parisc.  When
      gcc-6 failed to build three times in a row, I looked again at the TLB
      related code.  I found a couple of issues.  This is the first.
      
      In general, we need to ensure page table updates and corresponding TLB
      purges are atomic.  The attached patch fixes an instance in pci-dma.c
      where the page table update was not guarded by the TLB lock.
      
      Tested on rp3440 and c8000.  So far, no further random segmentation
      faults have been observed.
      Signed-off-by: NJohn David Anglin  <dave.anglin@bell.net>
      Cc: <stable@vger.kernel.org> # v3.16+
      Signed-off-by: NHelge Deller <deller@gmx.de>
      c0452fb9
    • H
      parisc: Switch to generic sched_clock implementation · 43b1f6ab
      Helge Deller 提交于
      Drop the open-coded sched_clock() function and replace it by the provided
      GENERIC_SCHED_CLOCK implementation.  We have seen quite some hung tasks in the
      past, which seem to be fixed by this patch.
      Signed-off-by: NHelge Deller <deller@gmx.de>
      Cc: <stable@vger.kernel.org> # v4.7+
      Signed-off-by: NHelge Deller <deller@gmx.de>
      43b1f6ab
    • J
      parisc: Fix races in parisc_setup_cache_timing() · 741dc7bf
      John David Anglin 提交于
      Helge reported to me the following startup crash:
      
      [    0.000000] Linux version 4.8.0-1-parisc64-smp (debian-kernel@lists.debian.org) (gcc version 5.4.1 20161019 (GCC) ) #1 SMP Debian 4.8.7-1 (2016-11-13)
      [    0.000000] The 64-bit Kernel has started...
      [    0.000000] Kernel default page size is 4 KB. Huge pages enabled with 1 MB physical and 2 MB virtual size.
      [    0.000000] Determining PDC firmware type: System Map.
      [    0.000000] model 9000/785/J5000
      [    0.000000] Total Memory: 2048 MB
      [    0.000000] Memory: 2018528K/2097152K available (9272K kernel code, 3053K rwdata, 1319K rodata, 1024K init, 840K bss, 78624K reserved, 0K cma-reserved)
      [    0.000000] virtual kernel memory layout:
      [    0.000000]     vmalloc : 0x0000000000008000 - 0x000000003f000000   (1007 MB)
      [    0.000000]     memory  : 0x0000000040000000 - 0x00000000c0000000   (2048 MB)
      [    0.000000]       .init : 0x0000000040100000 - 0x0000000040200000   (1024 kB)
      [    0.000000]       .data : 0x0000000040b0e000 - 0x0000000040f533e0   (4372 kB)
      [    0.000000]       .text : 0x0000000040200000 - 0x0000000040b0e000   (9272 kB)
      [    0.768910] Brought up 1 CPUs
      [    0.992465] NET: Registered protocol family 16
      [    2.429981] Releasing cpu 1 now, hpa=fffffffffffa2000
      [    2.635751] CPU(s): 2 out of 2 PA8500 (PCX-W) at 440.000000 MHz online
      [    2.726692] Setting cache flush threshold to 1024 kB
      [    2.729932] Not-handled unaligned insn 0x43ffff80
      [    2.798114] Setting TLB flush threshold to 140 kB
      [    2.928039] Unaligned handler failed, ret = -1
      [    3.000419]       _______________________________
      [    3.000419]      < Your System ate a SPARC! Gah! >
      [    3.000419]       -------------------------------
      [    3.000419]              \   ^__^
      [    3.000419]                  (__)\       )\/\
      [    3.000419]                   U  ||----w |
      [    3.000419]                      ||     ||
      [    9.340055] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.8.0-1-parisc64-smp #1 Debian 4.8.7-1
      [    9.448082] task: 00000000bfd48060 task.stack: 00000000bfd50000
      [    9.528040]
      [   10.760029] IASQ: 0000000000000000 0000000000000000 IAOQ: 000000004025d154 000000004025d158
      [   10.868052]  IIR: 43ffff80    ISR: 0000000000340000  IOR: 000001ff54150960
      [   10.960029]  CPU:        1   CR30: 00000000bfd50000 CR31: 0000000011111111
      [   11.052057]  ORIG_R28: 000000004021e3b4
      [   11.100045]  IAOQ[0]: irq_exit+0x94/0x120
      [   11.152062]  IAOQ[1]: irq_exit+0x98/0x120
      [   11.208031]  RP(r2): irq_exit+0xb8/0x120
      [   11.256074] Backtrace:
      [   11.288067]  [<00000000402cd944>] cpu_startup_entry+0x1e4/0x598
      [   11.368058]  [<0000000040109528>] smp_callin+0x2c0/0x2f0
      [   11.436308]  [<00000000402b53fc>] update_curr+0x18c/0x2d0
      [   11.508055]  [<00000000402b73b8>] dequeue_entity+0x2c0/0x1030
      [   11.584040]  [<00000000402b3cc0>] set_next_entity+0x80/0xd30
      [   11.660069]  [<00000000402c1594>] pick_next_task_fair+0x614/0x720
      [   11.740085]  [<000000004020dd34>] __schedule+0x394/0xa60
      [   11.808054]  [<000000004020e488>] schedule+0x88/0x118
      [   11.876039]  [<0000000040283d3c>] rescuer_thread+0x4d4/0x5b0
      [   11.948090]  [<000000004028fc4c>] kthread+0x1ec/0x248
      [   12.016053]  [<0000000040205020>] end_fault_vector+0x20/0xc0
      [   12.092239]  [<00000000402050c0>] _switch_to_ret+0x0/0xf40
      [   12.164044]
      [   12.184036] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.8.0-1-parisc64-smp #1 Debian 4.8.7-1
      [   12.244040] Backtrace:
      [   12.244040]  [<000000004021c480>] show_stack+0x68/0x80
      [   12.244040]  [<00000000406f332c>] dump_stack+0xec/0x168
      [   12.244040]  [<000000004021c74c>] die_if_kernel+0x25c/0x430
      [   12.244040]  [<000000004022d320>] handle_unaligned+0xb48/0xb50
      [   12.244040]
      [   12.632066] ---[ end trace 9ca05a7215c7bbb2 ]---
      [   12.692036] Kernel panic - not syncing: Attempted to kill the idle task!
      
      We have the insn 0x43ffff80 in IIR but from IAOQ we should have:
         4025d150:   0f f3 20 df     ldd,s r19(r31),r31
         4025d154:   0f 9f 00 9c     ldw r31(ret0),ret0
         4025d158:   bf 80 20 58     cmpb,*<> r0,ret0,4025d18c <irq_exit+0xcc>
      
      Cpu0 has just completed running parisc_setup_cache_timing:
      
      [    2.429981] Releasing cpu 1 now, hpa=fffffffffffa2000
      [    2.635751] CPU(s): 2 out of 2 PA8500 (PCX-W) at 440.000000 MHz online
      [    2.726692] Setting cache flush threshold to 1024 kB
      [    2.729932] Not-handled unaligned insn 0x43ffff80
      [    2.798114] Setting TLB flush threshold to 140 kB
      [    2.928039] Unaligned handler failed, ret = -1
      
      From the backtrace, cpu1 is in smp_callin:
      
      void __init smp_callin(void)
      {
             int slave_id = cpu_now_booting;
      
             smp_cpu_init(slave_id);
             preempt_disable();
      
             flush_cache_all_local(); /* start with known state */
             flush_tlb_all_local(NULL);
      
             local_irq_enable();  /* Interrupts have been off until now */
      
             cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
      
      So, it has just flushed its caches and the TLB. It would seem either the
      flushes in parisc_setup_cache_timing or smp_callin have corrupted kernel
      memory.
      
      The attached patch reworks parisc_setup_cache_timing to remove the races
      in setting the cache and TLB flush thresholds. It also corrects the
      number of bytes flushed in the TLB calculation.
      
      The patch flushes the cache and TLB on cpu0 before starting the
      secondary processors so that they are started from a known state.
      
      Tested with a few reboots on c8000.
      Signed-off-by: NJohn David Anglin  <dave.anglin@bell.net>
      Cc: <stable@vger.kernel.org> # v3.18+
      Signed-off-by: NHelge Deller <deller@gmx.de>
      741dc7bf
    • M
      MIPS: mm: Fix output of __do_page_fault · 2a872a5d
      Matt Redfearn 提交于
      Since commit 4bcc595c ("printk: reinstate KERN_CONT for printing
      continuation lines") the output from __do_page_fault on MIPS has been
      pretty unreadable due to the lack of KERN_CONT markers. Use pr_cont
      to provide the appropriate markers & restore the expected output.
      Signed-off-by: NMatt Redfearn <matt.redfearn@imgtec.com>
      Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
      Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
      Cc: Andrew Morton <akpm@linux-foundation.org>
      Cc: linux-mips@linux-mips.org
      Cc: linux-kernel@vger.kernel.org
      Patchwork: https://patchwork.linux-mips.org/patch/14544/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>
      2a872a5d
    • A
      powerpc/mm: Fixup kernel read only mapping · 984d7a1e
      Aneesh Kumar K.V 提交于
      With commit e58e87ad ("powerpc/mm: Update _PAGE_KERNEL_RO") we
      started using the ppp value 0b110 to map kernel readonly. But that
      facility was only added as part of ISA 2.04. For earlier ISA version
      only supported ppp bit value for readonly mapping is 0b011. (This
      implies both user and kernel get mapped using the same ppp bit value for
      readonly mapping.).
      Update the code such that for earlier architecture version we use ppp
      value 0b011 for readonly mapping. We don't differentiate between power5+
      and power5 here and apply the new ppp bits only from power6 (ISA 2.05).
      This keep the changes minimal.
      
      This fixes issue with PS3 spu usage reported at
      https://lkml.kernel.org/r/rep.1421449714.geoff@infradead.org
      
      Fixes: e58e87ad ("powerpc/mm: Update _PAGE_KERNEL_RO")
      Cc: stable@vger.kernel.org # v4.7+
      Tested-by: NGeoff Levand <geoff@infradead.org>
      Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
      Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      984d7a1e
    • R
      KVM: x86: check for pic and ioapic presence before use · df492896
      Radim Krčmář 提交于
      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: NDmitry Vyukov <dvyukov@google.com>
      Cc: stable@vger.kernel.org
      Fixes: 49df6397 ("KVM: x86: Split the APIC from the rest of IRQCHIP.")
      Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
      df492896
    • R
      KVM: x86: fix out-of-bounds accesses of rtc_eoi map · 81cdb259
      Radim Krčmář 提交于
      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: NDmitry Vyukov <dvyukov@google.com>
      Cc: stable@vger.kernel.org
      Fixes: af1bae54 ("KVM: x86: bump KVM_MAX_VCPU_ID to 1023")
      Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
      Reviewed-by: NDavid Hildenbrand <david@redhat.com>
      Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
      81cdb259
    • R
      KVM: x86: drop error recovery in em_jmp_far and em_ret_far · 2117d539
      Radim Krčmář 提交于
      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: NDmitry Vyukov <dvyukov@google.com>
      Cc: stable@vger.kernel.org
      Fixes: d1442d85 ("KVM: x86: Handle errors when RIP is set during far jumps")
      Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
      2117d539
    • R
      KVM: x86: fix out-of-bounds access in lapic · 444fdad8
      Radim Krčmář 提交于
      Cluster xAPIC delivery incorrectly assumed that dest_id <= 0xff.
      With enabled KVM_X2APIC_API_USE_32BIT_IDS in KVM_CAP_X2APIC_API, a
      userspace can send an interrupt with dest_id that results in
      out-of-bounds access.
      
      Found by syzkaller:
      
        BUG: KASAN: slab-out-of-bounds in kvm_irq_delivery_to_apic_fast+0x11fa/0x1210 at addr ffff88003d9ca750
        Read of size 8 by task syz-executor/22923
        CPU: 0 PID: 22923 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
         [...] kasan_object_err+0x1c/0x70 mm/kasan/report.c:156
         [...] print_address_description mm/kasan/report.c:194
         [...] kasan_report_error mm/kasan/report.c:283
         [...] kasan_report+0x231/0x500 mm/kasan/report.c:303
         [...] __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:329
         [...] kvm_irq_delivery_to_apic_fast+0x11fa/0x1210 arch/x86/kvm/lapic.c:824
         [...] kvm_irq_delivery_to_apic+0x132/0x9a0 arch/x86/kvm/irq_comm.c:72
         [...] kvm_set_msi+0x111/0x160 arch/x86/kvm/irq_comm.c:157
         [...] kvm_send_userspace_msi+0x201/0x280 arch/x86/kvm/../../../virt/kvm/irqchip.c:74
         [...] kvm_vm_ioctl+0xba5/0x1670 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3015
         [...] 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: NDmitry Vyukov <dvyukov@google.com>
      Cc: stable@vger.kernel.org
      Fixes: e45115b6 ("KVM: x86: use physical LAPIC array for logical x2APIC")
      Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
      Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
      444fdad8
  13. 24 11月, 2016 5 次提交
    • P
      MIPS: Mask out limit field when calculating wired entry count · 10313980
      Paul Burton 提交于
      Since MIPSr6 the Wired register is split into 2 fields, with the upper
      16 bits of the register indicating a limit on the value that the wired
      entry count in the bottom 16 bits of the register can take. This means
      that simply reading the wired register doesn't get us a valid TLB entry
      index any longer, and we instead need to retrieve only the lower 16 bits
      of the register. Introduce a new num_wired_entries() function which does
      this on MIPSr6 or higher and simply returns the value of the wired
      register on older architecture revisions, and make use of it when
      reading the number of wired entries.
      
      Since commit e710d666 ("MIPS: tlb-r4k: If there are wired entries,
      don't use TLBINVF") we have been using a non-zero number of wired
      entries to determine whether we should avoid use of the tlbinvf
      instruction (which would invalidate wired entries) and instead loop over
      TLB entries in local_flush_tlb_all(). This loop begins with the number
      of wired entries, or before this patch some large bogus TLB index on
      MIPSr6 systems. Thus since the aforementioned commit some MIPSr6 systems
      with FTLBs have been prone to leaving stale address translations in the
      FTLB & crashing in various weird & wonderful ways when we later observe
      the wrong memory.
      Signed-off-by: NPaul Burton <paul.burton@imgtec.com>
      Cc: Matt Redfearn <matt.redfearn@imgtec.com>
      Cc: linux-mips@linux-mips.org
      Patchwork: https://patchwork.linux-mips.org/patch/14557/Signed-off-by: NRalf Baechle <ralf@linux-mips.org>
      10313980
    • O
      powerpc/boot: Fix the early OPAL console wrappers · a1ff5741
      Oliver O'Halloran 提交于
      When configured with CONFIG_PPC_EARLY_DEBUG_OPAL=y the kernel expects
      the OPAL entry and base addresses to be passed in r8 and r9
      respectively. Currently the wrapper does not attempt to restore these
      values before entering the decompressed kernel which causes the kernel
      to branch into whatever happens to be in r9 when doing a write to the
      OPAL console in early boot.
      
      This patch adds a platform_ops hook that can be used to branch into the
      new kernel. The OPAL console driver patches this at runtime so that if
      the console is used it will be restored just prior to entering the
      kernel.
      
      Fixes: 656ad58e ("powerpc/boot: Add OPAL console to epapr wrappers")
      Cc: stable@vger.kernel.org # v4.8+
      Signed-off-by: NOliver O'Halloran <oohall@gmail.com>
      Signed-off-by: NMichael Ellerman <mpe@ellerman.id.au>
      a1ff5741
    • D
      x86/apic/uv: Silence a shift wrapping warning · c4597fd7
      Dan Carpenter 提交于
      'm_io' is stored in 6 bits so it's a number in the 0-63 range.  Static
      analysis tools complain that 1 << 63 will wrap so I have changed it to
      1ULL << m_io.
      
      This code is over three years old so presumably the bug doesn't happen
      very frequently in real life or someone would have complained by now.
      Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
      Cc: Alex Thorlton <athorlton@sgi.com>
      Cc: Dimitri Sivanich <sivanich@sgi.com>
      Cc: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Mike Travis <travis@sgi.com>
      Cc: Nathan Zimmer <nzimmer@sgi.com>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: kernel-janitors@vger.kernel.org
      Fixes: b15cc4a1 ("x86, uv, uv3: Update x2apic Support for SGI UV3")
      Link: http://lkml.kernel.org/r/20161123221908.GA23997@mwandaSigned-off-by: NIngo Molnar <mingo@kernel.org>
      c4597fd7
    • D
      x86/coredump: Always use user_regs_struct for compat_elf_gregset_t · 7b2dd368
      Dmitry Safonov 提交于
      Commit:
      
        90954e7b ("x86/coredump: Use pr_reg size, rather that TIF_IA32 flag")
      
      changed the coredumping code to construct the elf coredump file according
      to register set size - and that's good: if binary crashes with 32-bit code
      selector, generate 32-bit ELF core, otherwise - 64-bit core.
      
      That was made for restoring 32-bit applications on x86_64: we want
      32-bit application after restore to generate 32-bit ELF dump on crash.
      
      All was quite good and recently I started reworking 32-bit applications
      dumping part of CRIU: now it has two parasites (32 and 64) for seizing
      compat/native tasks, after rework it'll have one parasite, working in
      64-bit mode, to which 32-bit prologue long-jumps during infection.
      
      And while it has worked for my work machine, in VM with
      !CONFIG_X86_X32_ABI during reworking I faced that segfault in 32-bit
      binary, that has long-jumped to 64-bit mode results in dereference
      of garbage:
      
       32-victim[19266]: segfault at f775ef65 ip 00000000f775ef65 sp 00000000f776aa50 error 14
       BUG: unable to handle kernel paging request at ffffffffffffffff
       IP: [<ffffffff81332ce0>] strlen+0x0/0x20
       [...]
       Call Trace:
        [] elf_core_dump+0x11a9/0x1480
        [] do_coredump+0xa6b/0xe60
        [] get_signal+0x1a8/0x5c0
        [] do_signal+0x23/0x660
        [] exit_to_usermode_loop+0x34/0x65
        [] prepare_exit_to_usermode+0x2f/0x40
        [] retint_user+0x8/0x10
      
      That's because we have 64-bit registers set (with according total size)
      and we're writing it to elf_thread_core_info which has smaller size
      on !CONFIG_X86_X32_ABI. That lead to overwriting ELF notes part.
      
      Tested on 32-, 64-bit ELF crashes and on 32-bit binaries that have
      jumped with 64-bit code selector - all is readable with gdb.
      Signed-off-by: NDmitry Safonov <dsafonov@virtuozzo.com>
      Cc: Andy Lutomirski <luto@kernel.org>
      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: Linus Torvalds <torvalds@linux-foundation.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Cc: Thomas Gleixner <tglx@linutronix.de>
      Cc: Josh Poimboeuf <jpoimboe@redhat.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>
      Cc: linux-mm@kvack.org
      Fixes: 90954e7b ("x86/coredump: Use pr_reg size, rather that TIF_IA32 flag")
      Signed-off-by: NIngo Molnar <mingo@kernel.org>
      7b2dd368
    • C
      tile: avoid using clocksource_cyc2ns with absolute cycle count · e658a6f1
      Chris Metcalf 提交于
      For large values of "mult" and long uptimes, the intermediate
      result of "cycles * mult" can overflow 64 bits.  For example,
      the tile platform calls clocksource_cyc2ns with a 1.2 GHz clock;
      we have mult = 853, and after 208.5 days, we overflow 64 bits.
      
      Since clocksource_cyc2ns() is intended to be used for relative
      cycle counts, not absolute cycle counts, performance is more
      importance than accepting a wider range of cycle values.  So,
      just use mult_frac() directly in tile's sched_clock().
      
      Commit 4cecf6d4 ("sched, x86: Avoid unnecessary overflow
      in sched_clock") by Salman Qazi results in essentially the same
      generated code for x86 as this change does for tile.  In fact,
      a follow-on change by Salman introduced mult_frac() and switched
      to using it, so the C code was largely identical at that point too.
      
      Peter Zijlstra then added mul_u64_u32_shr() and switched x86
      to use it.  This is, in principle, better; by optimizing the
      64x64->64 multiplies to be 32x32->64 multiplies we can potentially
      save some time.  However, the compiler piplines the 64x64->64
      multiplies pretty well, and the conditional branch in the generic
      mul_u64_u32_shr() causes some bubbles in execution, with the
      result that it's pretty much a wash.  If tilegx provided its own
      implementation of mul_u64_u32_shr() without the conditional branch,
      we could potentially save 3 cycles, but that seems like small gain
      for a fair amount of additional build scaffolding; no other platform
      currently provides a mul_u64_u32_shr() override, and tile doesn't
      currently have an <asm/div64.h> header to put the override in.
      
      Additionally, gcc currently has an optimization bug that prevents
      it from recognizing the opportunity to use a 32x32->64 multiply,
      and so the result would be no better than the existing mult_frac()
      until such time as the compiler is fixed.
      
      For now, just using mult_frac() seems like the right answer.
      
      Cc: stable@kernel.org [v3.4+]
      Signed-off-by: NChris Metcalf <cmetcalf@mellanox.com>
      e658a6f1
  14. 23 11月, 2016 2 次提交
    • R
      Revert "arm: move exports to definitions" · 8478132a
      Russell King 提交于
      This reverts commit 4dd1837d.
      
      Moving the exports for assembly code into the assembly files breaks
      KSYM trimming, but also breaks modversions.
      
      While fixing the KSYM trimming is trivial, fixing modversions brings
      us to a technically worse position that we had prior to the above
      change:
      
      - We end up with the prototype definitions divorsed from everything
        else, which means that adding or removing assembly level ksyms
        become more fragile:
        * if adding a new assembly ksyms export, a missed prototype in
          asm-prototypes.h results in a successful build if no module in
          the selected configuration makes use of the symbol.
        * when removing a ksyms export, asm-prototypes.h will get forgotten,
          with armksyms.c, you'll get a build error if you forget to touch
          the file.
      
      - We end up with the same amount of include files and prototypes,
        they're just in a header file instead of a .c file with their
        exports.
      
      As for lines of code, we don't get much of a size reduction:
       (original commit)
       47 files changed, 131 insertions(+), 208 deletions(-)
       (fix for ksyms trimming)
       7 files changed, 18 insertions(+), 5 deletions(-)
       (two fixes for modversions)
       1 file changed, 34 insertions(+)
       3 files changed, 7 insertions(+), 2 deletions(-)
      which results in a net total of only 25 lines deleted.
      
      As there does not seem to be much benefit from this change of approach,
      revert the change.
      Signed-off-by: NRussell King <rmk+kernel@armlinux.org.uk>
      8478132a
    • L
      ARM: dts: STiH407-family: fix i2c nodes · 86b4522d
      Loic Pallardy 提交于
      The I2C nodes are missing #address-cells and #size-cells. This is
      causing warning at device tree compilation when some I2C device
      sub-nodes are defined.
      Signed-off-by: NLoic Pallardy <loic.pallardy@st.com>
      86b4522d