1. 23 10月, 2015 2 次提交
  2. 28 9月, 2015 1 次提交
    • V
      x86/xen: Support kexec/kdump in HVM guests by doing a soft reset · 0b34a166
      Vitaly Kuznetsov 提交于
      Currently there is a number of issues preventing PVHVM Xen guests from
      doing successful kexec/kdump:
      
        - Bound event channels.
        - Registered vcpu_info.
        - PIRQ/emuirq mappings.
        - shared_info frame after XENMAPSPACE_shared_info operation.
        - Active grant mappings.
      
      Basically, newly booted kernel stumbles upon already set up Xen
      interfaces and there is no way to reestablish them. In Xen-4.7 a new
      feature called 'soft reset' is coming. A guest performing kexec/kdump
      operation is supposed to call SCHEDOP_shutdown hypercall with
      SHUTDOWN_soft_reset reason before jumping to new kernel. Hypervisor
      (with some help from toolstack) will do full domain cleanup (but
      keeping its memory and vCPU contexts intact) returning the guest to
      the state it had when it was first booted and thus allowing it to
      start over.
      
      Doing SHUTDOWN_soft_reset on Xen hypervisors which don't support it is
      probably OK as by default all unknown shutdown reasons cause domain
      destroy with a message in toolstack log: 'Unknown shutdown reason code
      5. Destroying domain.'  which gives a clue to what the problem is and
      eliminates false expectations.
      Signed-off-by: NVitaly Kuznetsov <vkuznets@redhat.com>
      Cc: <stable@vger.kernel.org>
      Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
      0b34a166
  3. 09 9月, 2015 2 次提交
  4. 08 9月, 2015 1 次提交
  5. 03 9月, 2015 1 次提交
    • P
      xen-netback: add support for multicast control · 210c34dc
      Paul Durrant 提交于
      Xen's PV network protocol includes messages to add/remove ethernet
      multicast addresses to/from a filter list in the backend. This allows
      the frontend to request the backend only forward multicast packets
      which are of interest thus preventing unnecessary noise on the shared
      ring.
      
      The canonical netif header in git://xenbits.xen.org/xen.git specifies
      the message format (two more XEN_NETIF_EXTRA_TYPEs) so the minimal
      necessary changes have been pulled into include/xen/interface/io/netif.h.
      
      To prevent the frontend from extending the multicast filter list
      arbitrarily a limit (XEN_NETBK_MCAST_MAX) has been set to 64 entries.
      This limit is not specified by the protocol and so may change in future.
      If the limit is reached then the next XEN_NETIF_EXTRA_TYPE_MCAST_ADD
      sent by the frontend will be failed with NETIF_RSP_ERROR.
      Signed-off-by: NPaul Durrant <paul.durrant@citrix.com>
      Cc: Ian Campbell <ian.campbell@citrix.com>
      Cc: Wei Liu <wei.liu2@citrix.com>
      Acked-by: NWei Liu <wei.liu2@citrix.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      210c34dc
  6. 20 8月, 2015 6 次提交
  7. 20 5月, 2015 1 次提交
    • D
      xen/events: don't bind non-percpu VIRQs with percpu chip · 77bb3dfd
      David Vrabel 提交于
      A non-percpu VIRQ (e.g., VIRQ_CONSOLE) may be freed on a different
      VCPU than it is bound to.  This can result in a race between
      handle_percpu_irq() and removing the action in __free_irq() because
      handle_percpu_irq() does not take desc->lock.  The interrupt handler
      sees a NULL action and oopses.
      
      Only use the percpu chip/handler for per-CPU VIRQs (like VIRQ_TIMER).
      
        # cat /proc/interrupts | grep virq
         40:      87246          0  xen-percpu-virq      timer0
         44:          0          0  xen-percpu-virq      debug0
         47:          0      20995  xen-percpu-virq      timer1
         51:          0          0  xen-percpu-virq      debug1
         69:          0          0   xen-dyn-virq      xen-pcpu
         74:          0          0   xen-dyn-virq      mce
         75:         29          0   xen-dyn-virq      hvc_console
      Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
      Cc: <stable@vger.kernel.org>
      77bb3dfd
  8. 30 4月, 2015 1 次提交
    • B
      xen: Suspend ticks on all CPUs during suspend · 2b953a5e
      Boris Ostrovsky 提交于
      Commit 77e32c89 ("clockevents: Manage device's state separately for
      the core") decouples clockevent device's modes from states. With this
      change when a Xen guest tries to resume, it won't be calling its
      set_mode op which needs to be done on each VCPU in order to make the
      hypervisor aware that we are in oneshot mode.
      
      This happens because clockevents_tick_resume() (which is an intermediate
      step of resuming ticks on a processor) doesn't call clockevents_set_state()
      anymore and because during suspend clockevent devices on all VCPUs (except
      for the one doing the suspend) are left in ONESHOT state. As result, during
      resume the clockevents state machine will assume that device is already
      where it should be and doesn't need to be updated.
      
      To avoid this problem we should suspend ticks on all VCPUs during
      suspend.
      Signed-off-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
      Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
      2b953a5e
  9. 27 4月, 2015 1 次提交
  10. 15 4月, 2015 1 次提交
  11. 16 3月, 2015 3 次提交
  12. 02 3月, 2015 1 次提交
  13. 24 2月, 2015 1 次提交
    • D
      x86/xen: allow privcmd hypercalls to be preempted · fdfd811d
      David Vrabel 提交于
      Hypercalls submitted by user space tools via the privcmd driver can
      take a long time (potentially many 10s of seconds) if the hypercall
      has many sub-operations.
      
      A fully preemptible kernel may deschedule such as task in any upcall
      called from a hypercall continuation.
      
      However, in a kernel with voluntary or no preemption, hypercall
      continuations in Xen allow event handlers to be run but the task
      issuing the hypercall will not be descheduled until the hypercall is
      complete and the ioctl returns to user space.  These long running
      tasks may also trigger the kernel's soft lockup detection.
      
      Add xen_preemptible_hcall_begin() and xen_preemptible_hcall_end() to
      bracket hypercalls that may be preempted.  Use these in the privcmd
      driver.
      
      When returning from an upcall, call xen_maybe_preempt_hcall() which
      adds a schedule point if if the current task was within a preemptible
      hypercall.
      
      Since _cond_resched() can move the task to a different CPU, clear and
      set xen_in_preemptible_hcall around the call.
      Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
      Reviewed-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
      fdfd811d
  14. 28 1月, 2015 5 次提交
  15. 14 1月, 2015 1 次提交
  16. 13 1月, 2015 1 次提交
    • J
      x86/xen: properly retrieve NMI reason · f221b04f
      Jan Beulich 提交于
      Using the native code here can't work properly, as the hypervisor would
      normally have cleared the two reason bits by the time Dom0 gets to see
      the NMI (if passed to it at all). There's a shared info field for this,
      and there's an existing hook to use - just fit the two together. This
      is particularly relevant so that NMIs intended to be handled by APEI /
      GHES actually make it to the respective handler.
      
      Note that the hook can (and should) be used irrespective of whether
      being in Dom0, as accessing port 0x61 in a DomU would be even worse,
      while the shared info field would just hold zero all the time. Note
      further that hardware NMI handling for PVH doesn't currently work
      anyway due to missing code in the hypervisor (but it is expected to
      work the native rather than the PV way).
      Signed-off-by: NJan Beulich <jbeulich@suse.com>
      Reviewed-by: NBoris Ostrovsky <boris.ostrovsky@oracle.com>
      Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
      f221b04f
  17. 04 12月, 2014 2 次提交
  18. 06 10月, 2014 1 次提交
  19. 03 10月, 2014 1 次提交
  20. 23 9月, 2014 2 次提交
  21. 12 9月, 2014 1 次提交
  22. 30 7月, 2014 1 次提交
    • D
      x86/xen: safely map and unmap grant frames when in atomic context · b7dd0e35
      David Vrabel 提交于
      arch_gnttab_map_frames() and arch_gnttab_unmap_frames() are called in
      atomic context but were calling alloc_vm_area() which might sleep.
      
      Also, if a driver attempts to allocate a grant ref from an interrupt
      and the table needs expanding, then the CPU may already by in lazy MMU
      mode and apply_to_page_range() will BUG when it tries to re-enable
      lazy MMU mode.
      
      These two functions are only used in PV guests.
      
      Introduce arch_gnttab_init() to allocates the virtual address space in
      advance.
      
      Avoid the use of apply_to_page_range() by using saving and using the
      array of PTE addresses from the alloc_vm_area() call (which ensures
      that the required page tables are pre-allocated).
      Signed-off-by: NDavid Vrabel <david.vrabel@citrix.com>
      Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
      b7dd0e35
  23. 19 7月, 2014 3 次提交