kernel.git/drivers/xen/events.c, branch linux-3.7.y

xen/events: fix RCU warning, or Call idle notifier after irq_enter()

2012-11-07T15:41:27Z

exit_idle() should be called after irq_enter(), otherwise it throws: [ INFO: suspicious RCU usage. ] 3.6.5 #1 Not tainted ------------------------------- include/linux/rcupdate.h:725 rcu_read_lock() used illegally while idle! other info that might help us debug this: RCU used illegally from idle CPU! rcu_scheduler_active = 1, debug_locks = 1 RCU used illegally from extended quiescent state! 1 lock held by swapper/0/0: #0: (rcu_read_lock){......}, at: [] __atomic_notifier_call_chain+0x0/0x140 stack backtrace: Pid: 0, comm: swapper/0 Not tainted 3.6.5 #1 Call Trace: [] lockdep_rcu_suspicious+0xe2/0x130 [] __atomic_notifier_call_chain+0x12c/0x140 [] ? atomic_notifier_chain_unregister+0x90/0x90 [] ? trace_hardirqs_off+0xd/0x10 [] atomic_notifier_call_chain+0x16/0x20 [] exit_idle+0x43/0x50 [] xen_evtchn_do_upcall+0x25/0x50 [] xen_do_hypervisor_callback+0x1e/0x30 [] ? hypercall_page+0x3aa/0x1000 [] ? hypercall_page+0x3aa/0x1000 [] ? xen_safe_halt+0x10/0x20 [] ? default_idle+0xba/0x570 [] ? cpu_idle+0xdf/0x140 [] ? rest_init+0x135/0x144 [] ? csum_partial_copy_generic+0x16c/0x16c [] ? start_kernel+0x3db/0x3e8 [] ? repair_env_string+0x5a/0x5a [] ? x86_64_start_reservations+0x131/0x135 [] ? xen_start_kernel+0x465/0x46 Git commit 98ad1cc14a5c4fd658f9d72c6ba5c86dfd3ce0d5 Author: Frederic Weisbecker Date: Fri Oct 7 18:22:09 2011 +0200 x86: Call idle notifier after irq_enter() did this, but it missed the Xen code. Signed-off-by: Mojiong Qiu Cc: stable@vger.kernel.org # from 3.3 and newer. Signed-off-by: Konrad Rzeszutek Wilk

xen: events: pirq_check_eoi_map is X86 specific

2012-10-19T19:17:53Z

On ARM I see: drivers/xen/events.c:280:13: warning: 'pirq_check_eoi_map' defined but not used [-Wunused-function] Signed-off-by: Ian Campbell Cc: Stefano Stabellini Signed-off-by: Konrad Rzeszutek Wilk

xen: mark xen_init_IRQ __init

2012-10-02T16:34:56Z

xen_init_IRQ should be marked __init because it calls other functions marked __init and is always called by functions marked __init (on both x86 and arm). Also remove the unused EXPORT_SYMBOL_GPL(xen_init_IRQ). Both changes were introduced by "xen/arm: receive Xen events on ARM". Signed-off-by: Stefano Stabellini Signed-off-by: Konrad Rzeszutek Wilk

xen/arm: receive Xen events on ARM

2012-09-14T13:37:32Z

Compile events.c on ARM. Parse, map and enable the IRQ to get event notifications from the device tree (node "/xen"). Signed-off-by: Stefano Stabellini Acked-by: Konrad Rzeszutek Wilk

xen: clear IRQ_NOAUTOEN and IRQ_NOREQUEST

2012-08-23T14:18:12Z

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. Signed-off-by: Stefano Stabellini Acked-by: Konrad Rzeszutek Wilk Signed-off-by: Konrad Rzeszutek Wilk

xen/events: fix unmask_evtchn for PV on HVM guests

2012-08-23T14:18:07Z

When unmask_evtchn is called, if we already have an event pending, we just set evtchn_pending_sel waiting for local_irq_enable to be called. That is because PV guests set the irq_enable pvops to xen_irq_enable_direct in xen_setup_vcpu_info_placement: xen_irq_enable_direct is implemented in assembly in arch/x86/xen/xen-asm.S and call xen_force_evtchn_callback if XEN_vcpu_info_pending is set. However HVM guests (and ARM guests) do not change or do not have the irq_enable pvop, so evtchn_unmask cannot work properly for them. Considering that having the pending_irq bit set when unmask_evtchn is called is not very common, and it is simpler to keep the native_irq_enable implementation for HVM guests (and ARM guests), the best thing to do is just use the EVTCHNOP_unmask hypercall (Xen re-injects pending events in response). Signed-off-by: Stefano Stabellini Signed-off-by: Konrad Rzeszutek Wilk

Merge tag 'stable/for-linus-3.5-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

2012-06-16T00:17:15Z

Pull five Xen bug-fixes from Konrad Rzeszutek Wilk: - When booting as PVHVM we would try to use PV console - but would not validate the parameters causing us to crash during restore b/c we re-use the wrong event channel. - When booting on machines with SR-IOV PCI bridge we didn't check for the bridge and tried to use it. - Under AMD machines would advertise the APERFMPERF resulting in needless amount of MSRs from the guest. - A global value (xen_released_pages) was not subtracted at bootup when pages were added back in. This resulted in the balloon worker having the wrong account of how many pages were truly released. - Fix dead-lock when xen-blkfront is run in the same domain as xen-blkback. * tag 'stable/for-linus-3.5-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen: mark local pages as FOREIGN in the m2p_override xen/setup: filter APERFMPERF cpuid feature out xen/balloon: Subtract from xen_released_pages the count that is populated. xen/pci: Check for PCI bridge before using it. xen/events: Add WARN_ON when quick lookup found invalid type. xen/hvc: Check HVM_PARAM_CONSOLE_[EVTCHN|PFN] for correctness. xen/hvc: Fix error cases around HVM_PARAM_CONSOLE_PFN xen/hvc: Collapse error logic.

xen/events: Add WARN_ON when quick lookup found invalid type.

2012-05-30T14:16:24Z

All of the bind_XYZ_to_irq do a quick lookup to see if the event exists. And if it does, then the initialized IRQ number is returned instead of initializing a new IRQ number. This patch adds an extra logic to check that the type returned is proper one and that there is an IRQ handler setup for it. This patch has the benefit of being able to find drivers that are doing something naught. [v1: Enhanced based on Stefano's review] Signed-off-by: Konrad Rzeszutek Wilk

Merge tag 'stable/for-linus-3.5-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

2012-05-24T23:02:08Z

Pull Xen updates from Konrad Rzeszutek Wilk: "Features: * Extend the APIC ops implementation and add IRQ_WORKER vector support so that 'perf' can work properly. * Fix self-ballooning code, and balloon logic when booting as initial domain. * Move array printing code to generic debugfs * Support XenBus domains. * Lazily free grants when a domain is dead/non-existent. * In M2P code use batching calls Bug-fixes: * Fix NULL dereference in allocation failure path (hvc_xen) * Fix unbinding of IRQ_WORKER vector during vCPU hot-unplug * Fix HVM guest resume - we would leak an PIRQ value instead of reusing the existing one." Fix up add-add onflicts in arch/x86/xen/enlighten.c due to addition of apic ipi interface next to the new apic_id functions. * tag 'stable/for-linus-3.5-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen: do not map the same GSI twice in PVHVM guests. hvc_xen: NULL dereference on allocation failure xen: Add selfballoning memory reservation tunable. xenbus: Add support for xenbus backend in stub domain xen/smp: unbind irqworkX when unplugging vCPUs. xen: enter/exit lazy_mmu_mode around m2p_override calls xen/acpi/sleep: Enable ACPI sleep via the __acpi_os_prepare_sleep xen: implement IRQ_WORK_VECTOR handler xen: implement apic ipi interface xen/setup: update VA mapping when releasing memory during setup xen/setup: Combine the two hypercall functions - since they are quite similar. xen/setup: Populate freed MFNs from non-RAM E820 entries and gaps to E820 RAM xen/setup: Only print "Freeing XXX-YYY pfn range: Z pages freed" if Z > 0 xen/gnttab: add deferred freeing logic debugfs: Add support to print u32 array in debugfs xen/p2m: An early bootup variant of set_phys_to_machine xen/p2m: Collapse early_alloc_p2m_middle redundant checks. xen/p2m: Allow alloc_p2m_middle to call reserve_brk depending on argument xen/p2m: Move code around to allow for better re-usage.

xen: do not map the same GSI twice in PVHVM guests.

2012-05-21T18:11:36Z

PV on HVM guests map GSIs into event channels. At restore time the event channels are resumed by restore_pirqs. Device drivers might try to register the same GSI again through ACPI at restore time, but the GSI has already been mapped and bound by restore_pirqs. This patch detects these situations and avoids mapping the same GSI multiple times. Without this patch we get: (XEN) irq.c:2235: dom4: pirq 23 or emuirq 28 already mapped and waste a pirq. CC: stable@kernel.org Signed-off-by: Stefano Stabellini Signed-off-by: Konrad Rzeszutek Wilk