Commit Graph

75 Commits

Author SHA1 Message Date
Linus Torvalds
3ee31b89d9 xen: fixes and features for 4.14
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Merge tag 'for-linus-4.14b-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen updates from Juergen Gross:

 - the new pvcalls backend for routing socket calls from a guest to dom0

 - some cleanups of Xen code

 - a fix for wrong usage of {get,put}_cpu()

* tag 'for-linus-4.14b-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (27 commits)
  xen/mmu: set MMU_NORMAL_PT_UPDATE in remap_area_mfn_pte_fn
  xen: Don't try to call xen_alloc_p2m_entry() on autotranslating guests
  xen/events: events_fifo: Don't use {get,put}_cpu() in xen_evtchn_fifo_init()
  xen/pvcalls: use WARN_ON(1) instead of __WARN()
  xen: remove not used trace functions
  xen: remove unused function xen_set_domain_pte()
  xen: remove tests for pvh mode in pure pv paths
  xen-platform: constify pci_device_id.
  xen: cleanup xen.h
  xen: introduce a Kconfig option to enable the pvcalls backend
  xen/pvcalls: implement write
  xen/pvcalls: implement read
  xen/pvcalls: implement the ioworker functions
  xen/pvcalls: disconnect and module_exit
  xen/pvcalls: implement release command
  xen/pvcalls: implement poll command
  xen/pvcalls: implement accept command
  xen/pvcalls: implement listen command
  xen/pvcalls: implement bind command
  xen/pvcalls: implement connect command
  ...
2017-09-07 10:24:21 -07:00
Julien Grall
22f12f0df8 xen/events: events_fifo: Don't use {get,put}_cpu() in xen_evtchn_fifo_init()
When booting Linux as Xen guest with CONFIG_DEBUG_ATOMIC, the following
splat appears:

[    0.002323] Mountpoint-cache hash table entries: 1024 (order: 1, 8192 bytes)
[    0.019717] ASID allocator initialised with 65536 entries
[    0.020019] xen:grant_table: Grant tables using version 1 layout
[    0.020051] Grant table initialized
[    0.020069] BUG: sleeping function called from invalid context at /data/src/linux/mm/page_alloc.c:4046
[    0.020100] in_atomic(): 1, irqs_disabled(): 0, pid: 1, name: swapper/0
[    0.020123] no locks held by swapper/0/1.
[    0.020143] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.13.0-rc5 #598
[    0.020166] Hardware name: FVP Base (DT)
[    0.020182] Call trace:
[    0.020199] [<ffff00000808a5c0>] dump_backtrace+0x0/0x270
[    0.020222] [<ffff00000808a95c>] show_stack+0x24/0x30
[    0.020244] [<ffff000008c1ef20>] dump_stack+0xb8/0xf0
[    0.020267] [<ffff0000081128c0>] ___might_sleep+0x1c8/0x1f8
[    0.020291] [<ffff000008112948>] __might_sleep+0x58/0x90
[    0.020313] [<ffff0000082171b8>] __alloc_pages_nodemask+0x1c0/0x12e8
[    0.020338] [<ffff00000827a110>] alloc_page_interleave+0x38/0x88
[    0.020363] [<ffff00000827a904>] alloc_pages_current+0xdc/0xf0
[    0.020387] [<ffff000008211f38>] __get_free_pages+0x28/0x50
[    0.020411] [<ffff0000086566a4>] evtchn_fifo_alloc_control_block+0x2c/0xa0
[    0.020437] [<ffff0000091747b0>] xen_evtchn_fifo_init+0x38/0xb4
[    0.020461] [<ffff0000091746c0>] xen_init_IRQ+0x44/0xc8
[    0.020484] [<ffff000009128adc>] xen_guest_init+0x250/0x300
[    0.020507] [<ffff000008083974>] do_one_initcall+0x44/0x130
[    0.020531] [<ffff000009120df8>] kernel_init_freeable+0x120/0x288
[    0.020556] [<ffff000008c31ca8>] kernel_init+0x18/0x110
[    0.020578] [<ffff000008083710>] ret_from_fork+0x10/0x40
[    0.020606] xen:events: Using FIFO-based ABI
[    0.020658] Xen: initializing cpu0
[    0.027727] Hierarchical SRCU implementation.
[    0.036235] EFI services will not be available.
[    0.043810] smp: Bringing up secondary CPUs ...

This is because get_cpu() in xen_evtchn_fifo_init() will disable
preemption, but __get_free_page() might sleep (GFP_ATOMIC is not set).

xen_evtchn_fifo_init() will always be called before SMP is initialized,
so {get,put}_cpu() could be replaced by a simple smp_processor_id().

This also avoid to modify evtchn_fifo_alloc_control_block that will be
called in other context.

Signed-off-by: Julien Grall <julien.grall@arm.com>
Reported-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Fixes: 1fe565517b ("xen/events: use the FIFO-based ABI if available")
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2017-08-31 09:45:55 -04:00
Thomas Gleixner
4447ac1195 x86/idt: Simplify alloc_intr_gate()
The only users of alloc_intr_gate() are hypervisors, which both check the
used_vectors bitmap whether they have allocated the gate already. Move that
check into alloc_intr_gate() and simplify the users.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Juergen Gross <jgross@suse.com>
Reviewed-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
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: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20170828064959.580830286@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-29 12:07:28 +02:00
Liu Shuo
020db9d3c1 xen/events: Fix interrupt lost during irq_disable and irq_enable
Here is a device has xen-pirq-MSI interrupt. Dom0 might lost interrupt
during driver irq_disable/irq_enable. Here is the scenario,
 1. irq_disable -> disable_dynirq -> mask_evtchn(irq channel)
 2. dev interrupt raised by HW and Xen mark its evtchn as pending
 3. irq_enable -> startup_pirq -> eoi_pirq ->
    clear_evtchn(channel of irq) -> clear pending status
 4. consume_one_event process the irq event without pending bit assert
    which result in interrupt lost once
 5. No HW interrupt raising anymore.

Now use enable_dynirq for enable_pirq of xen_pirq_chip to remove
eoi_pirq when irq_enable.

Signed-off-by: Liu Shuo <shuo.a.liu@intel.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2017-08-11 16:46:01 +02:00
Juergen Gross
e91b2b1194 xen: dont fiddle with event channel masking in suspend/resume
Instead of fiddling with masking the event channels during suspend
and resume handling let do the irq subsystem do its job. It will do
the mask and unmask operations as needed.

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2017-07-27 19:55:46 +02:00
Linus Torvalds
6e6c5b9606 xen: features and fixes for 4.13-rc1
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Merge tag 'for-linus-4.13-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen updates from Juergen Gross:
 "Other than fixes and cleanups it contains:

   - support > 32 VCPUs at domain restore

   - support for new sysfs nodes related to Xen

   - some performance tuning for Linux running as Xen guest"

* tag 'for-linus-4.13-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  x86/xen: allow userspace access during hypercalls
  x86: xen: remove unnecessary variable in xen_foreach_remap_area()
  xen: allocate page for shared info page from low memory
  xen: avoid deadlock in xenbus driver
  xen: add sysfs node for hypervisor build id
  xen: sync include/xen/interface/version.h
  xen: add sysfs node for guest type
  doc,xen: document hypervisor sysfs nodes for xen
  xen/vcpu: Handle xen_vcpu_setup() failure at boot
  xen/vcpu: Handle xen_vcpu_setup() failure in hotplug
  xen/pv: Fix OOPS on restore for a PV, !SMP domain
  xen/pvh*: Support > 32 VCPUs at domain restore
  xen/vcpu: Simplify xen_vcpu related code
  xen-evtchn: Bind dyn evtchn:qemu-dm interrupt to next online VCPU
  xen: avoid type warning in xchg_xen_ulong
  xen: fix HYPERVISOR_dm_op() prototype
  xen: don't print error message in case of missing Xenstore entry
  arm/xen: Adjust one function call together with a variable assignment
  arm/xen: Delete an error message for a failed memory allocation in __set_phys_to_machine_multi()
  arm/xen: Improve a size determination in __set_phys_to_machine_multi()
2017-07-06 19:11:24 -07:00
Thomas Gleixner
ef1c2cc885 xen/events: Add support for effective affinity mask
Update the effective affinity mask when an interrupt was successfully
targeted to a CPU.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Christoph Hellwig <hch@lst.de>
Link: http://lkml.kernel.org/r/20170619235446.799944725@linutronix.de
2017-06-22 18:21:23 +02:00
Anoob Soman
c48f64ab47 xen-evtchn: Bind dyn evtchn:qemu-dm interrupt to next online VCPU
A HVM domian booting generates around 200K (evtchn:qemu-dm xen-dyn)
interrupts,in a short period of time. All these evtchn:qemu-dm are bound
to VCPU 0, until irqbalance sees these IRQ and moves it to a different VCPU.
In one configuration, irqbalance runs every 10 seconds, which means
irqbalance doesn't get to see these burst of interrupts and doesn't
re-balance interrupts most of the time, making all evtchn:qemu-dm to be
processed by VCPU0. This cause VCPU0 to spend most of time processing
hardirq and very little time on softirq. Moreover, if dom0 kernel PREEMPTION
is disabled, VCPU0 never runs watchdog (process context), triggering a
softlockup detection code to panic.

Binding evtchn:qemu-dm to next online VCPU, will spread hardirq
processing evenly across different CPU. Later, irqbalance will try to balance
evtchn:qemu-dm, if required.

Signed-off-by: Anoob Soman <anoob.soman@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2017-06-13 15:30:27 +02:00
Boris Ostrovsky
84d582d236 xen: Revert commits da72ff5bfc and 72a9b18629
Recent discussion (http://marc.info/?l=xen-devel&m=149192184523741)
established that commit 72a9b18629 ("xen: Remove event channel
notification through Xen PCI platform device") (and thus commit
da72ff5bfc ("partially revert "xen: Remove event channel
notification through Xen PCI platform device"")) are unnecessary and,
in fact, prevent HVM guests from booting on Xen releases prior to 4.0

Therefore we revert both of those commits.

The summary of that discussion is below:

  Here is the brief summary of the current situation:

  Before the offending commit (72a9b18629):

  1) INTx does not work because of the reset_watches path.
  2) The reset_watches path is only taken if you have Xen > 4.0
  3) The Linux Kernel by default will use vector inject if the hypervisor
     support. So even INTx does not work no body running the kernel with
     Xen > 4.0 would notice. Unless he explicitly disabled this feature
     either in the kernel or in Xen (and this can only be disabled by
     modifying the code, not user-supported way to do it).

  After the offending commit (+ partial revert):

  1) INTx is no longer support for HVM (only for PV guests).
  2) Any HVM guest The kernel will not boot on Xen < 4.0 which does
     not have vector injection support. Since the only other mode
     supported is INTx which.

  So based on this summary, I think before commit (72a9b18629) we were
  in much better position from a user point of view.

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2017-05-02 11:18:05 +02:00
Boris Ostrovsky
063334f305 xen/x86: Remove PVH support
We are replacing existing PVH guests with new implementation.

We are keeping xen_pvh_domain() macro (for now set to zero) because
when we introduce new PVH implementation later in this series we will
reuse current PVH-specific code (xen_pvh_gnttab_setup()), and that
code is conditioned by 'if (xen_pvh_domain())'. (We will also need
a noop xen_pvh_domain() for !CONFIG_XEN_PVH).

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2017-02-07 08:07:01 -05:00
Linus Torvalds
383378d115 xen: features and fixes for 4.10 rc2
- small fixes for xenbus driver
 - one fix for xen dom0 boot on huge system
 - small cleanups
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Merge tag 'for-linus-4.10-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen fixes and cleanups from Juergen Gross:

 - small fixes for xenbus driver

 - one fix for xen dom0 boot on huge system

 - small cleanups

* tag 'for-linus-4.10-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  Xen: ARM: Zero reserved fields of xatp before making hypervisor call
  xen: events: Replace BUG() with BUG_ON()
  xen: remove stale xs_input_avail() from header
  xen: return xenstore command failures via response instead of rc
  xen: xenbus driver must not accept invalid transaction ids
  xen/evtchn: use rb_entry()
  xen/setup: Don't relocate p2m over existing one
2017-01-05 10:29:40 -08:00
Shyam Saini
f9751a60f1 xen: events: Replace BUG() with BUG_ON()
Replace BUG() with BUG_ON() using coccinelle

Signed-off-by: Shyam Saini <mayhs11saini@gmail.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2017-01-03 14:37:39 +01:00
Thomas Gleixner
73c1b41e63 cpu/hotplug: Cleanup state names
When the state names got added a script was used to add the extra argument
to the calls. The script basically converted the state constant to a
string, but the cleanup to convert these strings into meaningful ones did
not happen.

Replace all the useless strings with 'subsys/xxx/yyy:state' strings which
are used in all the other places already.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Link: http://lkml.kernel.org/r/20161221192112.085444152@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-25 10:47:44 +01:00
Linus Torvalds
aa3ecf388a xen: features and fixes for 4.10 rc0
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Merge tag 'for-linus-4.10-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen updates from Juergen Gross:
 "Xen features and fixes for 4.10

  These are some fixes, a move of some arm related headers to share them
  between arm and arm64 and a series introducing a helper to make code
  more readable.

  The most notable change is David stepping down as maintainer of the
  Xen hypervisor interface. This results in me sending you the pull
  requests for Xen related code from now on"

* tag 'for-linus-4.10-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (29 commits)
  xen/balloon: Only mark a page as managed when it is released
  xenbus: fix deadlock on writes to /proc/xen/xenbus
  xen/scsifront: don't request a slot on the ring until request is ready
  xen/x86: Increase xen_e820_map to E820_X_MAX possible entries
  x86: Make E820_X_MAX unconditionally larger than E820MAX
  xen/pci: Bubble up error and fix description.
  xen: xenbus: set error code on failure
  xen: set error code on failures
  arm/xen: Use alloc_percpu rather than __alloc_percpu
  arm/arm64: xen: Move shared architecture headers to include/xen/arm
  xen/events: use xen_vcpu_id mapping for EVTCHNOP_status
  xen/gntdev: Use VM_MIXEDMAP instead of VM_IO to avoid NUMA balancing
  xen-scsifront: Add a missing call to kfree
  MAINTAINERS: update XEN HYPERVISOR INTERFACE
  xenfs: Use proc_create_mount_point() to create /proc/xen
  xen-platform: use builtin_pci_driver
  xen-netback: fix error handling output
  xen: make use of xenbus_read_unsigned() in xenbus
  xen: make use of xenbus_read_unsigned() in xen-pciback
  xen: make use of xenbus_read_unsigned() in xen-fbfront
  ...
2016-12-13 16:07:55 -08:00
Thomas Gleixner
34bc3560c6 x86: Remove empty idle.h header
One include less is always a good thing(tm). Good riddance.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/20161209182912.2726-6-bp@alien8.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-09 21:23:22 +01:00
Vitaly Kuznetsov
b36585a0a3 xen/events: use xen_vcpu_id mapping for EVTCHNOP_status
EVTCHNOP_status hypercall returns Xen's idea of vcpu id so we need to
compare it against xen_vcpu_id mapping, not the Linux cpu id.

Suggested-by: Radim Krcmar <rkrcmar@redhat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
2016-11-30 07:39:09 +01:00
Len Brown
7a3e686e1b x86/idle: Remove enter_idle(), exit_idle()
Upon removal of the is_idle flag, these routines became NOPs.

Signed-off-by: Len Brown <len.brown@intel.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: http://lkml.kernel.org/r/822f2c22cc5890f7b8ea0eeec60277eb44505b4e.1479449716.git.len.brown@intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-18 12:07:57 +01:00
KarimAllah Ahmed
72a9b18629 xen: Remove event channel notification through Xen PCI platform device
Ever since commit 254d1a3f02 ("xen/pv-on-hvm kexec: shutdown watches
from old kernel") using the INTx interrupt from Xen PCI platform
device for event channel notification would just lockup the guest
during bootup.  postcore_initcall now calls xs_reset_watches which
will eventually try to read a value from XenStore and will get stuck
on read_reply at XenBus forever since the platform driver is not
probed yet and its INTx interrupt handler is not registered yet. That
means that the guest can not be notified at this moment of any pending
event channels and none of the per-event handlers will ever be invoked
(including the XenStore one) and the reply will never be picked up by
the kernel.

The exact stack where things get stuck during xenbus_init:

-xenbus_init
 -xs_init
  -xs_reset_watches
   -xenbus_scanf
    -xenbus_read
     -xs_single
      -xs_single
       -xs_talkv

Vector callbacks have always been the favourite event notification
mechanism since their introduction in commit 38e20b07ef ("x86/xen:
event channels delivery on HVM.") and the vector callback feature has
always been advertised for quite some time by Xen that's why INTx was
broken for several years now without impacting anyone.

Luckily this also means that event channel notification through INTx
is basically dead-code which can be safely removed without impacting
anybody since it has been effectively disabled for more than 4 years
with nobody complaining about it (at least as far as I'm aware of).

This commit removes event channel notification through Xen PCI
platform device.

Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: David Vrabel <david.vrabel@citrix.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Julien Grall <julien.grall@citrix.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: Ross Lagerwall <ross.lagerwall@citrix.com>
Cc: xen-devel@lists.xenproject.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-pci@vger.kernel.org
Cc: Anthony Liguori <aliguori@amazon.com>
Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-09-30 11:44:34 +01:00
Sebastian Andrzej Siewior
c8761e2016 xen/events: Convert to hotplug state machine
Install the callbacks via the state machine.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-09-30 11:23:04 +01:00
Vitaly Kuznetsov
be78da1cf4 xen/events: fifo: use xen_vcpu_id mapping
EVTCHNOP_init_control has vCPU id as a parameter and Xen's idea of
vCPU id should be used. Use the newly introduced xen_vcpu_id mapping
to convert it from Linux's id.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-07-25 13:34:12 +01:00
Vitaly Kuznetsov
8058c0b897 xen/events: use xen_vcpu_id mapping in events_base
EVTCHNOP_bind_ipi and EVTCHNOP_bind_virq pass vCPU id as a parameter
and Xen's idea of vCPU id should be used. Use the newly introduced
xen_vcpu_id mapping to convert it from Linux's id.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-07-25 13:34:06 +01:00
Vitaly Kuznetsov
ad5475f9fa x86/xen: use xen_vcpu_id mapping for HYPERVISOR_vcpu_op
HYPERVISOR_vcpu_op() passes Linux's idea of vCPU id as a parameter
while Xen's idea is expected. In some cases these ideas diverge so we
need to do remapping.

Convert all callers of HYPERVISOR_vcpu_op() to use xen_vcpu_nr().

Leave xen_fill_possible_map() and xen_filter_cpu_maps() intact as
they're only being called by PV guests before perpu areas are
initialized. While the issue could be solved by switching to
early_percpu for xen_vcpu_id I think it's not worth it: PV guests will
probably never get to the point where their idea of vCPU id diverges
from Xen's.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-07-25 13:32:34 +01:00
Ross Lagerwall
f0f393877c xen/events: Don't move disabled irqs
Commit ff1e22e7a6 ("xen/events: Mask a moving irq") open-coded
irq_move_irq() but left out checking if the IRQ is disabled. This broke
resuming from suspend since it tries to move a (disabled) irq without
holding the IRQ's desc->lock. Fix it by adding in a check for disabled
IRQs.

The resulting stacktrace was:
kernel BUG at /build/linux-UbQGH5/linux-4.4.0/kernel/irq/migration.c:31!
invalid opcode: 0000 [#1] SMP
Modules linked in: xenfs xen_privcmd ...
CPU: 0 PID: 9 Comm: migration/0 Not tainted 4.4.0-22-generic #39-Ubuntu
Hardware name: Xen HVM domU, BIOS 4.6.1-xs125180 05/04/2016
task: ffff88003d75ee00 ti: ffff88003d7bc000 task.ti: ffff88003d7bc000
RIP: 0010:[<ffffffff810e26e2>]  [<ffffffff810e26e2>] irq_move_masked_irq+0xd2/0xe0
RSP: 0018:ffff88003d7bfc50  EFLAGS: 00010046
RAX: 0000000000000000 RBX: ffff88003d40ba00 RCX: 0000000000000001
RDX: 0000000000000001 RSI: 0000000000000100 RDI: ffff88003d40bad8
RBP: ffff88003d7bfc68 R08: 0000000000000000 R09: ffff88003d000000
R10: 0000000000000000 R11: 000000000000023c R12: ffff88003d40bad0
R13: ffffffff81f3a4a0 R14: 0000000000000010 R15: 00000000ffffffff
FS:  0000000000000000(0000) GS:ffff88003da00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd4264de624 CR3: 0000000037922000 CR4: 00000000003406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffff88003d40ba38 0000000000000024 0000000000000000 ffff88003d7bfca0
 ffffffff814c8d92 00000010813ef89d 00000000805ea732 0000000000000009
 0000000000000024 ffff88003cc39b80 ffff88003d7bfce0 ffffffff814c8f66
Call Trace:
 [<ffffffff814c8d92>] eoi_pirq+0xb2/0xf0
 [<ffffffff814c8f66>] __startup_pirq+0xe6/0x150
 [<ffffffff814ca659>] xen_irq_resume+0x319/0x360
 [<ffffffff814c7e75>] xen_suspend+0xb5/0x180
 [<ffffffff81120155>] multi_cpu_stop+0xb5/0xe0
 [<ffffffff811200a0>] ? cpu_stop_queue_work+0x80/0x80
 [<ffffffff811203d0>] cpu_stopper_thread+0xb0/0x140
 [<ffffffff810a94e6>] ? finish_task_switch+0x76/0x220
 [<ffffffff810ca731>] ? __raw_callee_save___pv_queued_spin_unlock+0x11/0x20
 [<ffffffff810a3935>] smpboot_thread_fn+0x105/0x160
 [<ffffffff810a3830>] ? sort_range+0x30/0x30
 [<ffffffff810a0588>] kthread+0xd8/0xf0
 [<ffffffff810a04b0>] ? kthread_create_on_node+0x1e0/0x1e0
 [<ffffffff8182568f>] ret_from_fork+0x3f/0x70
 [<ffffffff810a04b0>] ? kthread_create_on_node+0x1e0/0x1e0

Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-05-24 12:58:54 +01:00
Boris Ostrovsky
ff1e22e7a6 xen/events: Mask a moving irq
Moving an unmasked irq may result in irq handler being invoked on both
source and target CPUs.

With 2-level this can happen as follows:

On source CPU:
        evtchn_2l_handle_events() ->
            generic_handle_irq() ->
                handle_edge_irq() ->
                   eoi_pirq():
                       irq_move_irq(data);

                       /***** WE ARE HERE *****/

                       if (VALID_EVTCHN(evtchn))
                           clear_evtchn(evtchn);

If at this moment target processor is handling an unrelated event in
evtchn_2l_handle_events()'s loop it may pick up our event since target's
cpu_evtchn_mask claims that this event belongs to it *and* the event is
unmasked and still pending. At the same time, source CPU will continue
executing its own handle_edge_irq().

With FIFO interrupt the scenario is similar: irq_move_irq() may result
in a EVTCHNOP_unmask hypercall which, in turn, may make the event
pending on the target CPU.

We can avoid this situation by moving and clearing the event while
keeping event masked.

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-04-04 11:18:00 +01:00
Linus Torvalds
55fc733c7e xen: features and fixes for 4.6-rc0
- Make earlyprintk=xen work for HVM guests.
 - Remove module support for things never built as modules.
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Merge tag 'for-linus-4.6-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen updates from David Vrabel:
 "Features and fixes for 4.6:

  - Make earlyprintk=xen work for HVM guests

  - Remove module support for things never built as modules"

* tag 'for-linus-4.6-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  drivers/xen: make platform-pci.c explicitly non-modular
  drivers/xen: make sys-hypervisor.c explicitly non-modular
  drivers/xen: make xenbus_dev_[front/back]end explicitly non-modular
  drivers/xen: make [xen-]ballon explicitly non-modular
  xen: audit usages of module.h ; remove unnecessary instances
  xen/x86: Drop mode-selecting ifdefs in startup_xen()
  xen/x86: Zero out .bss for PV guests
  hvc_xen: make early_printk work with HVM guests
  hvc_xen: fix xenboot for DomUs
  hvc_xen: add earlycon support
2016-03-22 12:55:17 -07:00
Paul Gortmaker
59aa56bf2a xen: audit usages of module.h ; remove unnecessary instances
Code that uses no modular facilities whatsoever should not be
sourcing module.h at all, since that header drags in a bunch
of other headers with it.

Similarly, code that is not explicitly using modular facilities
like module_init() but only is declaring module_param setup
variables should be using moduleparam.h and not the larger
module.h file for that.

In making this change, we also uncover an implicit use of BUG()
in inline fcns within arch/arm/include/asm/xen/hypercall.h so
we explicitly source <linux/bug.h> for that file now.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2016-03-21 15:13:32 +00:00
Peter Zijlstra
25528213fe tags: Fix DEFINE_PER_CPU expansions
$ make tags
  GEN     tags
ctags: Warning: drivers/acpi/processor_idle.c:64: null expansion of name pattern "\1"
ctags: Warning: drivers/xen/events/events_2l.c:41: null expansion of name pattern "\1"
ctags: Warning: kernel/locking/lockdep.c:151: null expansion of name pattern "\1"
ctags: Warning: kernel/rcu/rcutorture.c:133: null expansion of name pattern "\1"
ctags: Warning: kernel/rcu/rcutorture.c:135: null expansion of name pattern "\1"
ctags: Warning: kernel/workqueue.c:323: null expansion of name pattern "\1"
ctags: Warning: net/ipv4/syncookies.c:53: null expansion of name pattern "\1"
ctags: Warning: net/ipv6/syncookies.c:44: null expansion of name pattern "\1"
ctags: Warning: net/rds/page.c:45: null expansion of name pattern "\1"

Which are all the result of the DEFINE_PER_CPU pattern:

  scripts/tags.sh:200:	'/\<DEFINE_PER_CPU([^,]*, *\([[:alnum:]_]*\)/\1/v/'
  scripts/tags.sh:201:	'/\<DEFINE_PER_CPU_SHARED_ALIGNED([^,]*, *\([[:alnum:]_]*\)/\1/v/'

The below cures them. All except the workqueue one are within reasonable
distance of the 80 char limit. TJ do you have any preference on how to
fix the wq one, or shall we just not care its too long?

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-03-15 16:55:16 -07:00
Michael S. Tsirkin
234927540e xen/events: use virt_xxx barriers
drivers/xen/events/events_fifo.c uses rmb() to communicate with the
other side.

For guests compiled with CONFIG_SMP, smp_rmb would be sufficient, so
rmb() here is only needed if a non-SMP guest runs on an SMP host.

Switch to the virt_rmb barrier which serves this exact purpose.

Pull in asm/barrier.h here to make sure the file is self-contained.

Suggested-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: David Vrabel <david.vrabel@citrix.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2016-01-12 20:47:04 +02:00
Ross Lagerwall
3de88d622f xen/events/fifo: Consume unprocessed events when a CPU dies
When a CPU is offlined, there may be unprocessed events on a port for
that CPU.  If the port is subsequently reused on a different CPU, it
could be in an unexpected state with the link bit set, resulting in
interrupts being missed. Fix this by consuming any unprocessed events
for a particular CPU when that CPU dies.

Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Cc: <stable@vger.kernel.org> # 3.14+
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-12-02 13:23:25 +00:00
Boris Ostrovsky
b4ff8389ed xen/events: Always allocate legacy interrupts on PV guests
After commit 8c058b0b9c ("x86/irq: Probe for PIC presence before
allocating descs for legacy IRQs") early_irq_init() will no longer
preallocate descriptors for legacy interrupts if PIC does not
exist, which is the case for Xen PV guests.

Therefore we may need to allocate those descriptors ourselves.

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-11-26 18:05:01 +00:00
Julien Grall
a001c9d95c xen/events: fifo: Make it running on 64KB granularity
Only use the first 4KB of the page to store the events channel info. It
means that we will waste 60KB every time we allocate page for:
     * control block: a page is allocating per CPU
     * event array: a page is allocating everytime we need to expand it

I think we can reduce the memory waste for the 2 areas by:

    * control block: sharing between multiple vCPUs. Although it will
    require some bookkeeping in order to not free the page when the CPU
    goes offline and the other CPUs sharing the page still there

    * event array: always extend the array event by 64K (i.e 16 4K
    chunk). That would require more care when we fail to expand the
    event channel.

Signed-off-by: Julien Grall <julien.grall@citrix.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-10-23 14:20:38 +01:00
Linus Torvalds
06ab838c20 xen: MFN/GFN/BFN terminology changes for 4.3-rc0
- Use the correct GFN/BFN terms more consistently.
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Merge tag 'for-linus-4.3-rc0b-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen terminology fixes from David Vrabel:
 "Use the correct GFN/BFN terms more consistently"

* tag 'for-linus-4.3-rc0b-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/xenbus: Rename the variable xen_store_mfn to xen_store_gfn
  xen/privcmd: Further s/MFN/GFN/ clean-up
  hvc/xen: Further s/MFN/GFN clean-up
  video/xen-fbfront: Further s/MFN/GFN clean-up
  xen/tmem: Use xen_page_to_gfn rather than pfn_to_gfn
  xen: Use correctly the Xen memory terminologies
  arm/xen: implement correctly pfn_to_mfn
  xen: Make clear that swiotlb and biomerge are dealing with DMA address
2015-09-10 16:21:11 -07:00
Linus Torvalds
752240e74d xen: features and fixes for 4.3-rc0
- Convert xen-blkfront to the multiqueue API
 - [arm] Support binding event channels to different VCPUs.
 - [x86] Support > 512 GiB in a PV guests (off by default as such a
   guest cannot be migrated with the current toolstack).
 - [x86] PMU support for PV dom0 (limited support for using perf with
   Xen and other guests).
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Merge tag 'for-linus-4.3-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen updates from David Vrabel:
 "Xen features and fixes for 4.3:

   - Convert xen-blkfront to the multiqueue API
   - [arm] Support binding event channels to different VCPUs.
   - [x86] Support > 512 GiB in a PV guests (off by default as such a
     guest cannot be migrated with the current toolstack).
   - [x86] PMU support for PV dom0 (limited support for using perf with
     Xen and other guests)"

* tag 'for-linus-4.3-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (33 commits)
  xen: switch extra memory accounting to use pfns
  xen: limit memory to architectural maximum
  xen: avoid another early crash of memory limited dom0
  xen: avoid early crash of memory limited dom0
  arm/xen: Remove helpers which are PV specific
  xen/x86: Don't try to set PCE bit in CR4
  xen/PMU: PMU emulation code
  xen/PMU: Intercept PMU-related MSR and APIC accesses
  xen/PMU: Describe vendor-specific PMU registers
  xen/PMU: Initialization code for Xen PMU
  xen/PMU: Sysfs interface for setting Xen PMU mode
  xen: xensyms support
  xen: remove no longer needed p2m.h
  xen: allow more than 512 GB of RAM for 64 bit pv-domains
  xen: move p2m list if conflicting with e820 map
  xen: add explicit memblock_reserve() calls for special pages
  mm: provide early_memremap_ro to establish read-only mapping
  xen: check for initrd conflicting with e820 map
  xen: check pre-allocated page tables for conflict with memory map
  xen: check for kernel memory conflicting with memory layout
  ...
2015-09-08 11:46:48 -07:00
Julien Grall
0df4f266b3 xen: Use correctly the Xen memory terminologies
Based on include/xen/mm.h [1], Linux is mistakenly using MFN when GFN
is meant, I suspect this is because the first support for Xen was for
PV. This resulted in some misimplementation of helpers on ARM and
confused developers about the expected behavior.

For instance, with pfn_to_mfn, we expect to get an MFN based on the name.
Although, if we look at the implementation on x86, it's returning a GFN.

For clarity and avoid new confusion, replace any reference to mfn with
gfn in any helpers used by PV drivers. The x86 code will still keep some
reference of pfn_to_mfn which may be used by all kind of guests
No changes as been made in the hypercall field, even
though they may be invalid, in order to keep the same as the defintion
in xen repo.

Note that page_to_mfn has been renamed to xen_page_to_gfn to avoid a
name to close to the KVM function gfn_to_page.

Take also the opportunity to simplify simple construction such
as pfn_to_mfn(page_to_pfn(page)) into xen_page_to_gfn. More complex clean up
will come in follow-up patches.

[1] http://xenbits.xen.org/gitweb/?p=xen.git;a=commitdiff;h=e758ed14f390342513405dd766e874934573e6cb

Signed-off-by: Julien Grall <julien.grall@citrix.com>
Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-09-08 18:03:49 +01:00
Julien Grall
4a5b69464e xen/events: Support event channel rebind on ARM
Currently, the event channel rebind code is gated with the presence of
the vector callback.

The virtual interrupt controller on ARM has the concept of per-CPU
interrupt (PPI) which allow us to support per-VCPU event channel.
Therefore there is no need of vector callback for ARM.

Xen is already using a free PPI to notify the guest VCPU of an event.
Furthermore, the xen code initialization in Linux (see
arch/arm/xen/enlighten.c) is requesting correctly a per-CPU IRQ.

Introduce new helper xen_support_evtchn_rebind to allow architecture
decide whether rebind an event is support or not. It will always return
true on ARM and keep the same behavior on x86.

This is also allow us to drop the usage of xen_have_vector_callback
entirely in the ARM code.

Signed-off-by: Julien Grall <julien.grall@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-08-20 12:24:15 +01:00
David Vrabel
ad6cd7bafc Revert "xen/events/fifo: Handle linked events when closing a port"
This reverts commit fcdf31a7c1.

This was causing a WARNING whenever a PIRQ was closed since
shutdown_pirq() is called with irqs disabled.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Cc: <stable@vger.kernel.org>
2015-08-11 11:05:42 +01:00
Ross Lagerwall
fcdf31a7c1 xen/events/fifo: Handle linked events when closing a port
An event channel bound to a CPU that was offlined may still be linked
on that CPU's queue.  If this event channel is closed and reused,
subsequent events will be lost because the event channel is never
unlinked and thus cannot be linked onto the correct queue.

When a channel is closed and the event is still linked into a queue,
ensure that it is unlinked before completing.

If the CPU to which the event channel bound is online, spin until the
event is handled by that CPU. If that CPU is offline, it can't handle
the event, so clear the event queue during the close, dropping the
events.

This fixes the missing interrupts (and subsequent disk stalls etc.)
when offlining a CPU.

Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-08-04 15:41:59 +01:00
Jiang Liu
c149e4cd08 x86/irq: Use access helper irq_data_get_affinity_mask()
This is a preparatory patch for moving irq_data struct members.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2015-07-13 21:22:47 +02:00
Julien Grall
a9fd60e268 xen: Include xen/page.h rather than asm/xen/page.h
Using xen/page.h will be necessary later for using common xen page
helpers.

As xen/page.h already include asm/xen/page.h, always use the later.

Signed-off-by: Julien Grall <julien.grall@citrix.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Wei Liu <wei.liu2@citrix.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: netdev@vger.kernel.org
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-06-17 16:14:18 +01:00
David Vrabel
77bb3dfdc0 xen/events: don't bind non-percpu VIRQs with percpu chip
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: David Vrabel <david.vrabel@citrix.com>
Cc: <stable@vger.kernel.org>
2015-05-19 19:55:36 +01:00
Boris Ostrovsky
16e6bd5970 xen/events: Set irq_info->evtchn before binding the channel to CPU in __startup_pirq()
.. because bind_evtchn_to_cpu(evtchn, cpu) will map evtchn to
'info' and pass 'info' down to xen_evtchn_port_bind_to_cpu().

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Tested-by: Annie Li <annie.li@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-05-05 18:27:14 +01:00
Boris Ostrovsky
5cec988349 xen/events: Clear cpu_evtchn_mask before resuming
When a guest is resumed, the hypervisor may change event channel
assignments. If this happens and the guest uses 2-level events it
is possible for the interrupt to be claimed by wrong VCPU since
cpu_evtchn_mask bits may be stale. This can happen even though
evtchn_2l_bind_to_cpu() attempts to clear old bits: irq_info that
is passed in is not necessarily the original one (from pre-migration
times) but instead is freshly allocated during resume and so any
information about which CPU the channel was bound to is lost.

Thus we should clear the mask during resume.

We also need to make sure that bits for xenstore and console channels
are set when these two subsystems are resumed. While rebind_evtchn_irq()
(which is invoked for both of them on a resume) calls irq_set_affinity(),
the latter will in fact postpone setting affinity until handling the
interrupt. But because cpu_evtchn_mask will have bits for these two
cleared we won't be able to take the interrupt.

With that in mind, we need to bind those two channels explicitly in
rebind_evtchn_irq(). We will keep irq_set_affinity() so that we have a
pass through generic irq affinity code later, in case something needs
to be updated there as well.

(Also replace cpumask_of(0) with cpumask_of(info->cpu) in
rebind_evtchn_irq(): it should be set to zero in preceding
xen_irq_info_evtchn_setup().)

Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reported-by: Annie Li <annie.li@oracle.com>
Cc: <stable@vger.kernel.org> # 3.14+
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-05-05 18:27:11 +01:00
Juergen Gross
85e40b0539 xen/events: avoid NULL pointer dereference in dom0 on large machines
Using the pvops kernel a NULL pointer dereference was detected on a
large machine (144 processors) when booting as dom0 in
evtchn_fifo_unmask() during assignment of a pirq.

The event channel in question was the first to need a new entry in
event_array[] in events_fifo.c. Unfortunately xen_irq_info_pirq_setup()
is called with evtchn being 0 for a new pirq and the real event channel
number is assigned to the pirq only during __startup_pirq().

It is mandatory to call xen_evtchn_port_setup() after assigning the
event channel number to the pirq to make sure all memory needed for the
event channel is allocated.

Signed-off-by: Juergen Gross <jgross@suse.com>
Cc: <stable@vger.kernel.org> # 3.14+
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2015-03-06 13:16:32 +00:00
Juergen Gross
854072dd0f xen/events: support threaded irqs for interdomain event channels
Export bind_interdomain_evtchn_to_irq() so drivers can use threaded
interrupt handlers with:

 irq = bind_interdomain_evtchn_to_irq(remote_dom, remote_port);
 if (irq < 0)
     /* error */
 ret = request_threaded_irq(...);

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-09-23 13:36:19 +00:00
Andrey Utkin
474b8feafb xen/events: drop negativity check of unsigned parameter
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=80531
Reported-by: David Binderman <dcb314@hotmail.com>
Signed-off-by: Andrey Utkin <andrey.krieger.utkin@gmail.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-08-01 15:44:45 +01:00
Frediano Ziglio
e4a7431240 xen/events/fifo: remove a unecessary use of BM()
Since 05a812ac47 (xen/events/fifo:
correctly align bitops), ready is an unsigned long instead of uint32_t
and the BM() macro is no longer required.

Signed-off-by: Frediano Ziglio <frediano.ziglio@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2014-07-31 17:59:18 +01:00
David Vrabel
dcecb8fd93 xen/events/fifo: ensure all bitops are properly aligned even on x86
When using the FIFO-based ABI on x86_64, if the last port is at the
end of an event array page then sync_test_bit() on this port's event
word will read beyond the end of the page and in certain circumstances
this may fault.

The fault requires the following page in the kernel's direct mapping
to be not present, which would mean:

a) the array page is the last page of RAM; or

b) the following page is ballooned out /and/ it has been used for a
   foreign mapping by a kernel driver (such as netback or blkback)
   /and/ the grant has been unmapped.

Use the infrastructure added for arm64 to ensure that all bitops
operating on event words are unsigned long aligned.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: stable@vger.kernel.org
2014-07-31 17:58:38 +01:00
David Vrabel
c12784c3d1 xen/events/fifo: reset control block and local HEADs on resume
When using the FIFO-based event channel ABI, if the control block or
the local HEADs are not reset after resuming the guest may see stale
HEAD values and will fail to traverse the FIFO correctly.

This may prevent one or more VCPUs from receiving any events following
a resume.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: stable@vger.kernel.org
2014-07-31 17:58:21 +01:00
Linus Torvalds
d09cc3659d Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into next
Pull core irq updates from Thomas Gleixner:
 "The irq department delivers:

   - Another tree wide update to get rid of the horrible create_irq
     interface along with its even more horrible variants.  That also
     gets rid of the last leftovers of the initial sparse irq hackery.
     arch/driver specific changes have been either acked or ignored.

   - A fix for the spurious interrupt detection logic with threaded
     interrupts.

   - A new ARM SoC interrupt controller

   - The usual pile of fixes and improvements all over the place"

* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (40 commits)
  Documentation: brcmstb-l2: Add Broadcom STB Level-2 interrupt controller binding
  irqchip: brcmstb-l2: Add Broadcom Set Top Box Level-2 interrupt controller
  genirq: Improve documentation to match current implementation
  ARM: iop13xx: fix msi support with sparse IRQ
  genirq: Provide !SMP stub for irq_set_affinity_notifier()
  irqchip: armada-370-xp: Move the devicetree binding documentation
  irqchip: gic: Use mask field in GICC_IAR
  genirq: Remove dynamic_irq mess
  ia64: Use irq_init_desc
  genirq: Replace dynamic_irq_init/cleanup
  genirq: Remove irq_reserve_irq[s]
  genirq: Replace reserve_irqs in core code
  s390: Avoid call to irq_reserve_irqs()
  s390: Remove pointless arch_show_interrupts()
  s390: pci: Check return value of alloc_irq_desc() proper
  sh: intc: Remove pointless irq_reserve_irqs() invocation
  x86, irq: Remove pointless irq_reserve_irqs() call
  genirq: Make create/destroy_irq() ia64 private
  tile: Use SPARSE_IRQ
  tile: pci: Use irq_alloc/free_hwirq()
  ...
2014-06-04 15:59:13 -07:00
Thomas Gleixner
d07c9f1875 x86: Get rid of get_nr_irqs_gsi()
No need to expose this outside of the ioapic code. The dynamic
allocations are guaranteed not to happen in the gsi space. See commit
62a08ae2a.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Grant Likely <grant.likely@linaro.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: x86@kernel.org
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/20140507154335.959870037@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2014-05-16 14:05:19 +02:00