1. 14 6月, 2016 1 次提交
    • J
      MIPS: KVM: Fix modular KVM under QEMU · 797179bc
      James Hogan 提交于
      Copy __kvm_mips_vcpu_run() into unmapped memory, so that we can never
      get a TLB refill exception in it when KVM is built as a module.
      
      This was observed to happen with the host MIPS kernel running under
      QEMU, due to a not entirely transparent optimisation in the QEMU TLB
      handling where TLB entries replaced with TLBWR are copied to a separate
      part of the TLB array. Code in those pages continue to be executable,
      but those mappings persist only until the next ASID switch, even if they
      are marked global.
      
      An ASID switch happens in __kvm_mips_vcpu_run() at exception level after
      switching to the guest exception base. Subsequent TLB mapped kernel
      instructions just prior to switching to the guest trigger a TLB refill
      exception, which enters the guest exception handlers without updating
      EPC. This appears as a guest triggered TLB refill on a host kernel
      mapped (host KSeg2) address, which is not handled correctly as user
      (guest) mode accesses to kernel (host) segments always generate address
      error exceptions.
      Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
      Cc: Paolo Bonzini <pbonzini@redhat.com>
      Cc: Radim Krčmář <rkrcmar@redhat.com>
      Cc: Ralf Baechle <ralf@linux-mips.org>
      Cc: kvm@vger.kernel.org
      Cc: linux-mips@linux-mips.org
      Cc: <stable@vger.kernel.org> # 3.10.x-
      Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      797179bc
  2. 03 6月, 2016 1 次提交
    • L
      Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm · 4340fa55
      Linus Torvalds 提交于
      Pull KVM fixes from Radim Krčmář:
       "ARM:
         - two fixes for 4.6 vgic [Christoffer] (cc stable)
      
         - six fixes for 4.7 vgic [Marc]
      
        x86:
         - six fixes from syzkaller reports [Paolo] (two of them cc stable)
      
         - allow OS X to boot [Dmitry]
      
         - don't trust compilers [Nadav]"
      
      * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
        KVM: x86: fix OOPS after invalid KVM_SET_DEBUGREGS
        KVM: x86: avoid vmalloc(0) in the KVM_SET_CPUID
        KVM: irqfd: fix NULL pointer dereference in kvm_irq_map_gsi
        KVM: fail KVM_SET_VCPU_EVENTS with invalid exception number
        KVM: x86: avoid vmalloc(0) in the KVM_SET_CPUID
        kvm: x86: avoid warning on repeated KVM_SET_TSS_ADDR
        KVM: Handle MSR_IA32_PERF_CTL
        KVM: x86: avoid write-tearing of TDP
        KVM: arm/arm64: vgic-new: Removel harmful BUG_ON
        arm64: KVM: vgic-v3: Relax synchronization when SRE==1
        arm64: KVM: vgic-v3: Prevent the guest from messing with ICC_SRE_EL1
        arm64: KVM: Make ICC_SRE_EL1 access return the configured SRE value
        KVM: arm/arm64: vgic-v3: Always resample level interrupts
        KVM: arm/arm64: vgic-v2: Always resample level interrupts
        KVM: arm/arm64: vgic-v3: Clear all dirty LRs
        KVM: arm/arm64: vgic-v2: Clear all dirty LRs
      4340fa55
  3. 02 6月, 2016 12 次提交
    • P
      KVM: x86: fix OOPS after invalid KVM_SET_DEBUGREGS · d14bdb55
      Paolo Bonzini 提交于
      MOV to DR6 or DR7 causes a #GP if an attempt is made to write a 1 to
      any of bits 63:32.  However, this is not detected at KVM_SET_DEBUGREGS
      time, and the next KVM_RUN oopses:
      
         general protection fault: 0000 [#1] SMP
         CPU: 2 PID: 14987 Comm: a.out Not tainted 4.4.9-300.fc23.x86_64 #1
         Hardware name: LENOVO 2325F51/2325F51, BIOS G2ET32WW (1.12 ) 05/30/2012
         [...]
         Call Trace:
          [<ffffffffa072c93d>] kvm_arch_vcpu_ioctl_run+0x141d/0x14e0 [kvm]
          [<ffffffffa071405d>] kvm_vcpu_ioctl+0x33d/0x620 [kvm]
          [<ffffffff81241648>] do_vfs_ioctl+0x298/0x480
          [<ffffffff812418a9>] SyS_ioctl+0x79/0x90
          [<ffffffff817a0f2e>] entry_SYSCALL_64_fastpath+0x12/0x71
         Code: 55 83 ff 07 48 89 e5 77 27 89 ff ff 24 fd 90 87 80 81 0f 23 fe 5d c3 0f 23 c6 5d c3 0f 23 ce 5d c3 0f 23 d6 5d c3 0f 23 de 5d c3 <0f> 23 f6 5d c3 0f 0b 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00
         RIP  [<ffffffff810639eb>] native_set_debugreg+0x2b/0x40
          RSP <ffff88005836bd50>
      
      Testcase (beautified/reduced from syzkaller output):
      
          #include <unistd.h>
          #include <sys/syscall.h>
          #include <string.h>
          #include <stdint.h>
          #include <linux/kvm.h>
          #include <fcntl.h>
          #include <sys/ioctl.h>
      
          long r[8];
      
          int main()
          {
              struct kvm_debugregs dr = { 0 };
      
              r[2] = open("/dev/kvm", O_RDONLY);
              r[3] = ioctl(r[2], KVM_CREATE_VM, 0);
              r[4] = ioctl(r[3], KVM_CREATE_VCPU, 7);
      
              memcpy(&dr,
                     "\x5d\x6a\x6b\xe8\x57\x3b\x4b\x7e\xcf\x0d\xa1\x72"
                     "\xa3\x4a\x29\x0c\xfc\x6d\x44\x00\xa7\x52\xc7\xd8"
                     "\x00\xdb\x89\x9d\x78\xb5\x54\x6b\x6b\x13\x1c\xe9"
                     "\x5e\xd3\x0e\x40\x6f\xb4\x66\xf7\x5b\xe3\x36\xcb",
                     48);
              r[7] = ioctl(r[4], KVM_SET_DEBUGREGS, &dr);
              r[6] = ioctl(r[4], KVM_RUN, 0);
          }
      Reported-by: NDmitry Vyukov <dvyukov@google.com>
      Cc: stable@vger.kernel.org
      Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
      d14bdb55
    • P
      KVM: x86: avoid vmalloc(0) in the KVM_SET_CPUID · f8c1b85b
      Paolo Bonzini 提交于
      This causes an ugly dmesg splat.  Beautified syzkaller testcase:
      
          #include <unistd.h>
          #include <sys/syscall.h>
          #include <sys/ioctl.h>
          #include <fcntl.h>
          #include <linux/kvm.h>
      
          long r[8];
      
          int main()
          {
              struct kvm_irq_routing ir = { 0 };
              r[2] = open("/dev/kvm", O_RDWR);
              r[3] = ioctl(r[2], KVM_CREATE_VM, 0);
              r[4] = ioctl(r[3], KVM_SET_GSI_ROUTING, &ir);
              return 0;
          }
      Reported-by: NDmitry Vyukov <dvyukov@google.com>
      Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
      f8c1b85b
    • P
      KVM: irqfd: fix NULL pointer dereference in kvm_irq_map_gsi · c622a3c2
      Paolo Bonzini 提交于
      Found by syzkaller:
      
          BUG: unable to handle kernel NULL pointer dereference at 0000000000000120
          IP: [<ffffffffa0797202>] kvm_irq_map_gsi+0x12/0x90 [kvm]
          PGD 6f80b067 PUD b6535067 PMD 0
          Oops: 0000 [#1] SMP
          CPU: 3 PID: 4988 Comm: a.out Not tainted 4.4.9-300.fc23.x86_64 #1
          [...]
          Call Trace:
           [<ffffffffa0795f62>] irqfd_update+0x32/0xc0 [kvm]
           [<ffffffffa0796c7c>] kvm_irqfd+0x3dc/0x5b0 [kvm]
           [<ffffffffa07943f4>] kvm_vm_ioctl+0x164/0x6f0 [kvm]
           [<ffffffff81241648>] do_vfs_ioctl+0x298/0x480
           [<ffffffff812418a9>] SyS_ioctl+0x79/0x90
           [<ffffffff817a1062>] tracesys_phase2+0x84/0x89
          Code: b5 71 a7 e0 5b 41 5c 41 5d 5d f3 c3 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48 8b 8f 10 2e 00 00 31 c0 48 89 e5 <39> 91 20 01 00 00 76 6a 48 63 d2 48 8b 94 d1 28 01 00 00 48 85
          RIP  [<ffffffffa0797202>] kvm_irq_map_gsi+0x12/0x90 [kvm]
           RSP <ffff8800926cbca8>
          CR2: 0000000000000120
      
      Testcase:
      
          #include <unistd.h>
          #include <sys/syscall.h>
          #include <string.h>
          #include <stdint.h>
          #include <linux/kvm.h>
          #include <fcntl.h>
          #include <sys/ioctl.h>
      
          long r[26];
      
          int main()
          {
              memset(r, -1, sizeof(r));
              r[2] = open("/dev/kvm", 0);
              r[3] = ioctl(r[2], KVM_CREATE_VM, 0);
      
              struct kvm_irqfd ifd;
              ifd.fd = syscall(SYS_eventfd2, 5, 0);
              ifd.gsi = 3;
              ifd.flags = 2;
              ifd.resamplefd = ifd.fd;
              r[25] = ioctl(r[3], KVM_IRQFD, &ifd);
              return 0;
          }
      Reported-by: NDmitry Vyukov <dvyukov@google.com>
      Cc: stable@vger.kernel.org
      Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
      c622a3c2
    • P
      KVM: fail KVM_SET_VCPU_EVENTS with invalid exception number · 78e546c8
      Paolo Bonzini 提交于
      This cannot be returned by KVM_GET_VCPU_EVENTS, so it is okay to return
      EINVAL.  It causes a WARN from exception_type:
      
          WARNING: CPU: 3 PID: 16732 at arch/x86/kvm/x86.c:345 exception_type+0x49/0x50 [kvm]()
          CPU: 3 PID: 16732 Comm: a.out Tainted: G        W       4.4.6-300.fc23.x86_64 #1
          Hardware name: LENOVO 2325F51/2325F51, BIOS G2ET32WW (1.12 ) 05/30/2012
           0000000000000286 000000006308a48b ffff8800bec7fcf8 ffffffff813b542e
           0000000000000000 ffffffffa0966496 ffff8800bec7fd30 ffffffff810a40f2
           ffff8800552a8000 0000000000000000 00000000002c267c 0000000000000001
          Call Trace:
           [<ffffffff813b542e>] dump_stack+0x63/0x85
           [<ffffffff810a40f2>] warn_slowpath_common+0x82/0xc0
           [<ffffffff810a423a>] warn_slowpath_null+0x1a/0x20
           [<ffffffffa0924809>] exception_type+0x49/0x50 [kvm]
           [<ffffffffa0934622>] kvm_arch_vcpu_ioctl_run+0x10a2/0x14e0 [kvm]
           [<ffffffffa091c04d>] kvm_vcpu_ioctl+0x33d/0x620 [kvm]
           [<ffffffff81241248>] do_vfs_ioctl+0x298/0x480
           [<ffffffff812414a9>] SyS_ioctl+0x79/0x90
           [<ffffffff817a04ee>] entry_SYSCALL_64_fastpath+0x12/0x71
          ---[ end trace b1a0391266848f50 ]---
      
      Testcase (beautified/reduced from syzkaller output):
      
          #include <unistd.h>
          #include <sys/syscall.h>
          #include <string.h>
          #include <stdint.h>
          #include <fcntl.h>
          #include <sys/ioctl.h>
          #include <linux/kvm.h>
      
          long r[31];
      
          int main()
          {
              memset(r, -1, sizeof(r));
              r[2] = open("/dev/kvm", O_RDONLY);
              r[3] = ioctl(r[2], KVM_CREATE_VM, 0);
              r[7] = ioctl(r[3], KVM_CREATE_VCPU, 0);
      
              struct kvm_vcpu_events ve = {
                      .exception.injected = 1,
                      .exception.nr = 0xd4
              };
              r[27] = ioctl(r[7], KVM_SET_VCPU_EVENTS, &ve);
              r[30] = ioctl(r[7], KVM_RUN, 0);
              return 0;
          }
      Reported-by: NDmitry Vyukov <dvyukov@google.com>
      Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
      78e546c8
    • P
      KVM: x86: avoid vmalloc(0) in the KVM_SET_CPUID · 83676e92
      Paolo Bonzini 提交于
      This causes an ugly dmesg splat.  Beautified syzkaller testcase:
      
          #include <unistd.h>
          #include <sys/syscall.h>
          #include <sys/ioctl.h>
          #include <fcntl.h>
          #include <linux/kvm.h>
      
          long r[8];
      
          int main()
          {
              struct kvm_cpuid2 c = { 0 };
              r[2] = open("/dev/kvm", O_RDWR);
              r[3] = ioctl(r[2], KVM_CREATE_VM, 0);
              r[4] = ioctl(r[3], KVM_CREATE_VCPU, 0x8);
              r[7] = ioctl(r[4], KVM_SET_CPUID, &c);
              return 0;
          }
      Reported-by: NDmitry Vyukov <dvyukov@google.com>
      Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
      83676e92
    • P
      kvm: x86: avoid warning on repeated KVM_SET_TSS_ADDR · b21629da
      Paolo Bonzini 提交于
      Found by syzkaller:
      
          WARNING: CPU: 3 PID: 15175 at arch/x86/kvm/x86.c:7705 __x86_set_memory_region+0x1dc/0x1f0 [kvm]()
          CPU: 3 PID: 15175 Comm: a.out Tainted: G        W       4.4.6-300.fc23.x86_64 #1
          Hardware name: LENOVO 2325F51/2325F51, BIOS G2ET32WW (1.12 ) 05/30/2012
           0000000000000286 00000000950899a7 ffff88011ab3fbf0 ffffffff813b542e
           0000000000000000 ffffffffa0966496 ffff88011ab3fc28 ffffffff810a40f2
           00000000000001fd 0000000000003000 ffff88014fc50000 0000000000000000
          Call Trace:
           [<ffffffff813b542e>] dump_stack+0x63/0x85
           [<ffffffff810a40f2>] warn_slowpath_common+0x82/0xc0
           [<ffffffff810a423a>] warn_slowpath_null+0x1a/0x20
           [<ffffffffa09251cc>] __x86_set_memory_region+0x1dc/0x1f0 [kvm]
           [<ffffffffa092521b>] x86_set_memory_region+0x3b/0x60 [kvm]
           [<ffffffffa09bb61c>] vmx_set_tss_addr+0x3c/0x150 [kvm_intel]
           [<ffffffffa092f4d4>] kvm_arch_vm_ioctl+0x654/0xbc0 [kvm]
           [<ffffffffa091d31a>] kvm_vm_ioctl+0x9a/0x6f0 [kvm]
           [<ffffffff81241248>] do_vfs_ioctl+0x298/0x480
           [<ffffffff812414a9>] SyS_ioctl+0x79/0x90
           [<ffffffff817a04ee>] entry_SYSCALL_64_fastpath+0x12/0x71
      
      Testcase:
      
          #include <unistd.h>
          #include <sys/ioctl.h>
          #include <fcntl.h>
          #include <string.h>
          #include <linux/kvm.h>
      
          long r[8];
      
          int main()
          {
              memset(r, -1, sizeof(r));
      	r[2] = open("/dev/kvm", O_RDONLY|O_TRUNC);
              r[3] = ioctl(r[2], KVM_CREATE_VM, 0x0ul);
              r[5] = ioctl(r[3], KVM_SET_TSS_ADDR, 0x20000000ul);
              r[7] = ioctl(r[3], KVM_SET_TSS_ADDR, 0x20000000ul);
              return 0;
          }
      Reported-by: NDmitry Vyukov <dvyukov@google.com>
      Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
      Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
      b21629da
    • D
      KVM: Handle MSR_IA32_PERF_CTL · 0c2df2a1
      Dmitry Bilunov 提交于
      Intel CPUs having Turbo Boost feature implement an MSR to provide a
      control interface via rdmsr/wrmsr instructions. One could detect the
      presence of this feature by issuing one of these instructions and
      handling the #GP exception which is generated in case the referenced MSR
      is not implemented by the CPU.
      
      KVM's vCPU model behaves exactly as a real CPU in this case by injecting
      a fault when MSR_IA32_PERF_CTL is called (which KVM does not support).
      However, some operating systems use this register during an early boot
      stage in which their kernel is not capable of handling #GP correctly,
      causing #DP and finally a triple fault effectively resetting the vCPU.
      
      This patch implements a dummy handler for MSR_IA32_PERF_CTL to avoid the
      crashes.
      Signed-off-by: NDmitry Bilunov <kmeaw@yandex-team.ru>
      Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
      0c2df2a1
    • N
      KVM: x86: avoid write-tearing of TDP · b19ee2ff
      Nadav Amit 提交于
      In theory, nothing prevents the compiler from write-tearing PTEs, or
      split PTE writes. These partially-modified PTEs can be fetched by other
      cores and cause mayhem. I have not really encountered such case in
      real-life, but it does seem possible.
      
      For example, the compiler may try to do something creative for
      kvm_set_pte_rmapp() and perform multiple writes to the PTE.
      Signed-off-by: NNadav Amit <nadav.amit@gmail.com>
      Signed-off-by: NRadim Krčmář <rkrcmar@redhat.com>
      b19ee2ff
    • R
      Merge tag 'kvm-arm-for-v4.7-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm · 13e98fd1
      Radim Krčmář 提交于
      KVM/ARM Fixes for v4.7-rc2
      
      Fixes for the vgic, 2 of the patches address a bug introduced in v4.6
      while the rest are for the new vgic.
      13e98fd1
    • M
      KVM: arm/arm64: vgic-new: Removel harmful BUG_ON · 05fb05a6
      Marc Zyngier 提交于
      When changing the active bit from an MMIO trap, we decide to
      explode if the intid is that of a private interrupt.
      
      This flawed logic comes from the fact that we were assuming that
      kvm_vcpu_kick() as called by kvm_arm_halt_vcpu() would not return before
      the called vcpu responded, but this is not the case, so we need to
      perform this wait even for private interrupts.
      
      Dropping the BUG_ON seems like the right thing to do.
      
       [ Commit message tweaked by Christoffer ]
      Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
      Signed-off-by: NChristoffer Dall <christoffer.dall@linaro.org>
      05fb05a6
    • L
      Merge tag 'pinctrl-v4.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl · 719af93a
      Linus Torvalds 提交于
      Pull pin control fixes from Linus Walleij:
       "Here are three pin control fixes for v4.7.  Not much, and just driver
        fixes:
      
         - add device tree matches to MAINTAINERS
      
         - inversion bug in the Nomadik driver
      
         - dual edge handling bug in the mediatek driver"
      
      * tag 'pinctrl-v4.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
        pinctrl: mediatek: fix dual-edge code defect
        MAINTAINERS: Add file patterns for pinctrl device tree bindings
        pinctrl: nomadik: fix inversion of gpio direction
      719af93a
    • L
      Merge tag 'dma-buf-for-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/sumits/dma-buf · ebb8cb2b
      Linus Torvalds 提交于
      Pull dma-buf updates from Sumit Semwal:
      
       - use of vma_pages instead of explicit computation
      
       - DocBook and headerdoc updates for dma-buf
      
      * tag 'dma-buf-for-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/sumits/dma-buf:
        dma-buf: use vma_pages()
        fence: add missing descriptions for fence
        doc: update/fixup dma-buf related DocBook
        reservation: add headerdoc comments
        dma-buf: headerdoc fixes
      ebb8cb2b
  4. 01 6月, 2016 23 次提交
  5. 31 5月, 2016 3 次提交