kernel.git/drivers/xen/events.c, branch linux-3.11.y

xen/events: mask events when changing their VCPU binding

2013-08-20T14:13:04Z

When a event is being bound to a VCPU there is a window between the EVTCHNOP_bind_vpcu call and the adjustment of the local per-cpu masks where an event may be lost. The hypervisor upcalls the new VCPU but the kernel thinks that event is still bound to the old VCPU and ignores it. There is even a problem when the event is being bound to the same VCPU as there is a small window beween the clear_bit() and set_bit() calls in bind_evtchn_to_cpu(). When scanning for pending events, the kernel may read the bit when it is momentarily clear and ignore the event. Avoid this by masking the event during the whole bind operation. Signed-off-by: David Vrabel Signed-off-by: Konrad Rzeszutek Wilk Reviewed-by: Jan Beulich CC: stable@vger.kernel.org

xen/events: initialize local per-cpu mask for all possible events

2013-08-20T14:13:02Z

The sizeof() argument in init_evtchn_cpu_bindings() is incorrect resulting in only the first 64 (or 32 in 32-bit guests) ports having their bindings being initialized to VCPU 0. In most cases this does not cause a problem as request_irq() will set the irq affinity which will set the correct local per-cpu mask. However, if the request_irq() is called on a VCPU other than 0, there is a window between the unmasking of the event and the affinity being set were an event may be lost because it is not locally unmasked on any VCPU. If request_irq() is called on VCPU 0 then local irqs are disabled during the window and the race does not occur. Fix this by initializing all NR_EVENT_CHANNEL bits in the local per-cpu masks. Signed-off-by: David Vrabel Signed-off-by: Konrad Rzeszutek Wilk CC: stable@vger.kernel.org

xen: Convert printks to pr_

2013-06-28T15:19:58Z

Convert printks to pr_ (excludes printk(KERN_DEBUG...) to be more consistent throughout the xen subsystem. Add pr_fmt with KBUILD_MODNAME or "xen:" KBUILD_MODNAME Coalesce formats and add missing word spaces Add missing newlines Align arguments and reflow to 80 columns Remove DRV_NAME from formats as pr_fmt adds the same content This does change some of the prefixes of these messages but it also does make them more consistent. Signed-off-by: Joe Perches Signed-off-by: Konrad Rzeszutek Wilk

Merge tag 'stable/for-linus-3.10-rc0-tag-two' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

2013-05-11T23:19:30Z

Pull Xen bug-fixes from Konrad Rzeszutek Wilk: - More fixes in the vCPU PVHVM hotplug path. - Add more documentation. - Fix various ARM related issues in the Xen generic drivers. - Updates in the xen-pciback driver per Bjorn's updates. - Mask the x2APIC feature for PV guests. * tag 'stable/for-linus-3.10-rc0-tag-two' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen/pci: Used cached MSI-X capability offset xen/pci: Use PCI_MSIX_TABLE_BIR, not PCI_MSIX_FLAGS_BIRMASK xen: clear IRQ_NOAUTOEN and IRQ_NOREQUEST xen: mask x2APIC feature in PV xen: SWIOTLB is only used on x86 xen/spinlock: Fix check from greater than to be also be greater or equal to. xen/smp/pvhvm: Don't point per_cpu(xen_vpcu, 33 and larger) to shared_info xen/vcpu: Document the xen_vcpu_info and xen_vcpu xen/vcpu/pvhvm: Fix vcpu hotplugging hanging.

xen: clear IRQ_NOAUTOEN and IRQ_NOREQUEST

2013-05-08T12:38:12Z

Reset the IRQ_NOAUTOEN and IRQ_NOREQUEST flags that are enabled by default on ARM. If IRQ_NOAUTOEN is set, __setup_irq doesn't call irq_startup, that is responsible for calling irq_unmask at startup time. As a result event channels remain masked. The clear is already made in bind_evtchn_to_irq with commit a8636c0 but was missing on all others bind_*_to_irq. Move the clear in xen_irq_info_common_init. On x86, IRQ_NOAUTOEN and IRQ_NOREQUEST are cleared by default, so this commit doesn't impact this architecture. Acked-by: Stefano Stabellini Signed-off-by: Julien Grall Signed-off-by: Konrad Rzeszutek Wilk

Merge tag 'stable/for-linus-3.10-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

2013-04-29T15:16:51Z

Pull Xen updates from Konrad Rzeszutek Wilk: "Features: - Populate the boot_params with EDD data. - Cleanups in the IRQ code. Bug-fixes: - CPU hotplug offline/online in PVHVM mode. - Re-upload processor PM data after ACPI S3 suspend/resume cycle." And Konrad gets a gold star for sending the pull request early when he thought he'd be away for the first week of the merge window (but because of 3.9 dragging out to -rc8 he then re-sent the reminder on the first day of the merge window anyway) * tag 'stable/for-linus-3.10-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen: resolve section mismatch warnings in xen-acpi-processor xen: Re-upload processor PM data to hypervisor after S3 resume (v2) xen/smp: Unifiy some of the PVs and PVHVM offline CPU path xen/smp/pvhvm: Don't initialize IRQ_WORKER as we are using the native one. xen/spinlock: Disable IRQ spinlock (PV) allocation on PVHVM xen/spinlock: Check against default value of -1 for IRQ line. xen/time: Add default value of -1 for IRQ and check for that. xen/events: Check that IRQ value passed in is valid. xen/time: Fix kasprintf splat when allocating timer%d IRQ line. xen/smp/spinlock: Fix leakage of the spinlock interrupt line for every CPU online/offline xen/smp: Fix leakage of timer interrupt line for every CPU online/offline. xen kconfig: fix select INPUT_XEN_KBDDEV_FRONTEND xen: drop tracking of IRQ vector x86/xen: populate boot_params with EDD data

xen/events: Check that IRQ value passed in is valid.

2013-04-16T20:05:13Z

We naively assume that the IRQ value passed in is correct. If it is not, then any dereference operation for the 'info' structure will result in crash - so might as well guard ourselves and sprinkle copious amounts of WARN_ON. Signed-off-by: Konrad Rzeszutek Wilk

xen: drop tracking of IRQ vector

2013-04-16T19:05:45Z

For quite a few Xen versions, this wasn't the IRQ vector anymore anyway, and it is not being used by the kernel for anything. Hence drop the field from struct irq_info, and respective function parameters. Signed-off-by: Jan Beulich Acked-by: Stefano Stabellini Signed-off-by: Konrad Rzeszutek Wilk

xen/events: Handle VIRQ_TIMER before any other hardirq in event loop.

2013-04-02T18:01:21Z

This avoids any other hardirq handler seeing a very stale jiffies value immediately after wakeup from a long idle period. The one observable symptom of this was a USB keyboard, with software keyboard repeat, which would always repeat a key immediately that it was pressed. This is due to the key press waking the guest, the key handler immediately runs, sees an old jiffies value, and then that jiffies value significantly updated, before the key is unpressed. Reviewed-by: David Vrabel Signed-off-by: Keir Fraser Signed-off-by: Konrad Rzeszutek Wilk

xen/events: avoid race with raising an event in unmask_evtchn()

2013-03-27T16:06:04Z

In unmask_evtchn(), when the mask bit is cleared after testing for pending and the event becomes pending between the test and clear, then the upcall will not become pending and the event may be lost or delayed. Avoid this by always clearing the mask bit before checking for pending. If a hypercall is needed, remask the event as EVTCHNOP_unmask will only retrigger pending events if they were masked. This fixes a regression introduced in 3.7 by b5e579232d635b79a3da052964cb357ccda8d9ea (xen/events: fix unmask_evtchn for PV on HVM guests) which reordered the clear mask and check pending operations. Changes in v2: - set mask before hypercall. Cc: stable@vger.kernel.org Acked-by: Stefano Stabellini Signed-off-by: David Vrabel Signed-off-by: Konrad Rzeszutek Wilk