1142 Commits

Author SHA1 Message Date
David Vrabel
95afae4814 xen: remove DEFINE_XENBUS_DRIVER() macro
The DEFINE_XENBUS_DRIVER() macro looks a bit weird and causes sparse
errors.

Replace the uses with standard structure definitions instead.  This is
similar to pci and usb device registration.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-10-06 10:27:57 +01:00
Chen Gang
305559f165 xen/xenbus: Remove BUG_ON() when error string trucated
xenbus_va_dev_error() is for printing error, so when error string is
too long to be truncated, need not BUG_ON(), still return truncation
string is OK.

Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-10-06 10:27:56 +01:00
Chen Gang
c7440a2f22 xen/xenbus: Correct the comments for xenbus_grant_ring()
A grant reference (which is a positive number) can indicate success, so
the original comments need be improved.

Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-10-06 10:27:56 +01:00
Daniel Kiper
342cd340f6 xen/efi: Directly include needed headers
I discovered that some needed stuff is defined/declared in headers
which are not included directly. Currently it works but if somebody
remove required headers from currently included headers then build
will break. So, just in case directly include all needed headers.

Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-09-23 13:36:20 +00:00
Dan Carpenter
495daef902 xen-scsiback: clean up a type issue in scsiback_make_tpg()
This code was confusing because we had an unsigned long and then we
compared it to UINT_MAX and then we stored it in a u16.  How many bytes
is this supposed to have: 2, 4 or 16???

I've made it a u16 throughout.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-09-23 13:36:20 +00:00
Juergen Gross
d9d660f6e5 xen-scsiback: Add Xen PV SCSI backend driver
Introduces the Xen pvSCSI backend. With pvSCSI it is possible for a
Xen domU to issue SCSI commands to a SCSI LUN assigned to that
domU. The SCSI commands are passed to the pvSCSI backend in a driver
domain (usually Dom0) which is owner of the physical device. This
allows e.g. to use SCSI tape drives in a Xen domU.

The code is taken from the pvSCSI implementation in Xen done by
Fujitsu based on Linux kernel 2.6.18.

Changes from the original version are:
- port to upstream kernel
- put all code in just one source file
- adapt to Linux style guide
- use target core infrastructure instead doing pure pass-through
- enable module unloading
- support SG-list in grant page(s)
- support task abort
- remove redundant struct backend
- allocate resources dynamically
- correct minor error in scsiback_fast_flush_area
- free allocated resources in case of error during I/O preparation
- remove CDB emulation, now handled by target core infrastructure

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-09-23 13:36:19 +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
Chen Gang
46e3626adb xen/grant-table: refactor error cleanup in grow_gnttab_list()
The cleanup loop in grow_gnttab_list() is safe from the underflow of
the unsigned 'i' since nr_glist_frames is >= 1, but refactor it
anyway.

Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-09-23 13:36:18 +00:00
Ethan Zhao
be507fd090 xen/pciback: Use PCI device flag helper functions
Use PCI device flag helper functions when assigning or releasing device.
No functional change.

Signed-off-by: Ethan Zhao <ethan.zhao@oracle.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: David Vrabel <david.vrabel@citrix.com>
2014-09-16 16:19:17 -06:00
Linus Torvalds
7ee2d2d671 xen: bug fixes for 3.17-rc4
- Fix for PVHVM suspend/resume and migration
 - Don't pointlessly retry certain ballooning ops
 - Fix gntalloc when grefs have run out.
 - Fix PV boot if KSALR is enable or very large modules are used.
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Merge tag 'stable/for-linus-3.17-b-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull Xen bug fixes from David Vrabel:
 - fix for PVHVM suspend/resume and migration
 - don't pointlessly retry certain ballooning ops
 - fix gntalloc when grefs have run out.
 - fix PV boot if KSALR is enable or very large modules are used.

* tag 'stable/for-linus-3.17-b-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  x86/xen: don't copy bogus duplicate entries into kernel page tables
  xen/gntalloc: safely delete grefs in add_grefs() undo path
  xen/gntalloc: fix oops after runnning out of grant refs
  xen/balloon: cancel ballooning if adding new memory failed
  xen/manage: Always freeze/thaw processes when suspend/resuming
2014-09-11 16:52:29 -07:00
David Vrabel
5903c6bd1a xen/gntalloc: safely delete grefs in add_grefs() undo path
If a gref could not be added (perhaps because the limit has been
reached or there are no more grant references available), the undo
path may crash because __del_gref() frees the gref while it is being
used for a list iteration.

A comment suggests that using list_for_each_entry() is safe since the
gref isn't removed from the list being iterated over, but it is freed
and thus list_for_each_entry_safe() must be used.

Also, explicitly delete the gref from the local per-file list, even
though this is not strictly necessary.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2014-09-04 13:14:05 +01:00
David Vrabel
e9de2e5fd6 xen/gntalloc: fix oops after runnning out of grant refs
Only set gref->gref_id if foreign access was successfully granted and
the grant ref is valid.

If gref->gref_id == -ENOSPC the test in __del_gref() would incorrectly
attempt to end foreign access (because grant_ref_t is unsigned).

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reported-by: Dave Scott <dave.scott@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2014-09-04 13:13:13 +01:00
David Vrabel
3dcf63677d xen/balloon: cancel ballooning if adding new memory failed
If the balloon driver is adding additional memory regions to the
balloon and add_memory() fails it will likely continuously fail so
cancel the balloon operation.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2014-09-02 15:37:19 +01:00
Ross Lagerwall
61a734d305 xen/manage: Always freeze/thaw processes when suspend/resuming
Always freeze processes when suspending and thaw processes when resuming
to prevent a race noticeable with HVM guests.

This prevents a deadlock where the khubd kthread (which is designed to
be freezable) acquires a usb device lock and then tries to allocate
memory which requires the disk which hasn't been resumed yet.
Meanwhile, the xenwatch thread deadlocks waiting for the usb device
lock.

Freezing processes fixes this because the khubd thread is only thawed
after the xenwatch thread finishes resuming all the devices.

Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Cc: stable@vger.kernel.org
2014-09-02 15:36:59 +01:00
Benoit Taine
9baa3c34ac PCI: Remove DEFINE_PCI_DEVICE_TABLE macro use
We should prefer `struct pci_device_id` over `DEFINE_PCI_DEVICE_TABLE` to
meet kernel coding style guidelines.  This issue was reported by checkpatch.

A simplified version of the semantic patch that makes this change is as
follows (http://coccinelle.lip6.fr/):

// <smpl>

@@
identifier i;
declarer name DEFINE_PCI_DEVICE_TABLE;
initializer z;
@@

- DEFINE_PCI_DEVICE_TABLE(i)
+ const struct pci_device_id i[]
= z;

// </smpl>

[bhelgaas: add semantic patch]
Signed-off-by: Benoit Taine <benoit.taine@lip6.fr>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-08-12 12:15:14 -06:00
Linus Torvalds
e306e3be1c - Remove unused V2 grant table support.
- Note that Konrad is xen-blkkback/front maintainer.
 - Add 'xen_nopv' option to disable PV extentions for x86 HVM guests.
 - Misc. minor cleanups.
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Merge tag 'stable/for-linus-3.17-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull Xen updates from David Vrabel:
 - remove unused V2 grant table support
 - note that Konrad is xen-blkkback/front maintainer
 - add 'xen_nopv' option to disable PV extentions for x86 HVM guests
 - misc minor cleanups

* tag 'stable/for-linus-3.17-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen-pciback: Document the 'quirks' sysfs file
  xen/pciback: Fix error return code in xen_pcibk_attach()
  xen/events: drop negativity check of unsigned parameter
  xen/setup: Remove Identity Map Debug Message
  xen/events/fifo: remove a unecessary use of BM()
  xen/events/fifo: ensure all bitops are properly aligned even on x86
  xen/events/fifo: reset control block and local HEADs on resume
  xen/arm: use BUG_ON
  xen/grant-table: remove support for V2 tables
  x86/xen: safely map and unmap grant frames when in atomic context
  MAINTAINERS: Make me the Xen block subsystem (front and back) maintainer
  xen: Introduce 'xen_nopv' to disable PV extensions for HVM guests.
2014-08-07 11:33:15 -07:00
Linus Torvalds
76f09aa464 Merge branch 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull EFI changes from Ingo Molnar:
 "Main changes in this cycle are:

   - arm64 efi stub fixes, preservation of FP/SIMD registers across
     firmware calls, and conversion of the EFI stub code into a static
     library - Ard Biesheuvel

   - Xen EFI support - Daniel Kiper

   - Support for autoloading the efivars driver - Lee, Chun-Yi

   - Use the PE/COFF headers in the x86 EFI boot stub to request that
     the stub be loaded with CONFIG_PHYSICAL_ALIGN alignment - Michael
     Brown

   - Consolidate all the x86 EFI quirks into one file - Saurabh Tangri

   - Additional error logging in x86 EFI boot stub - Ulf Winkelvos

   - Support loading initrd above 4G in EFI boot stub - Yinghai Lu

   - EFI reboot patches for ACPI hardware reduced platforms"

* 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (31 commits)
  efi/arm64: Handle missing virtual mapping for UEFI System Table
  arch/x86/xen: Silence compiler warnings
  xen: Silence compiler warnings
  x86/efi: Request desired alignment via the PE/COFF headers
  x86/efi: Add better error logging to EFI boot stub
  efi: Autoload efivars
  efi: Update stale locking comment for struct efivars
  arch/x86: Remove efi_set_rtc_mmss()
  arch/x86: Replace plain strings with constants
  xen: Put EFI machinery in place
  xen: Define EFI related stuff
  arch/x86: Remove redundant set_bit(EFI_MEMMAP) call
  arch/x86: Remove redundant set_bit(EFI_SYSTEM_TABLES) call
  efi: Introduce EFI_PARAVIRT flag
  arch/x86: Do not access EFI memory map if it is not available
  efi: Use early_mem*() instead of early_io*()
  arch/ia64: Define early_memunmap()
  x86/reboot: Add EFI reboot quirk for ACPI Hardware Reduced flag
  efi/reboot: Allow powering off machines using EFI
  efi/reboot: Add generic wrapper around EfiResetSystem()
  ...
2014-08-04 17:13:50 -07:00
Wei Yongjun
2ef760323a xen/pciback: Fix error return code in xen_pcibk_attach()
Fix to return -EFAULT from the error handling case instead of 0 when
version mismatch with pcifront.

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Reviewed-by Jan Beulich <jbeulich@suse.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-08-01 15:44:46 +01:00
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 05a812ac474d0d6aef6d54b66bb08b81abde79c6 (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
acba648dca Fix BUG when trying to expand the grant table. This seems to occur
often during boot with Ubuntu 14.04 PV guests.
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Merge tag 'stable/for-linus-3.16-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull Xen fix from David Vrabel:
 "Fix BUG when trying to expand the grant table.  This seems to occur
  often during boot with Ubuntu 14.04 PV guests"

* tag 'stable/for-linus-3.16-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  x86/xen: safely map and unmap grant frames when in atomic context
2014-07-30 09:00:20 -07:00
David Vrabel
b7dd0e350e x86/xen: safely map and unmap grant frames when in atomic context
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: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2014-07-30 14:22:47 +01:00
Daniel Kiper
be81c8a1da xen: Put EFI machinery in place
This patch enables EFI usage under Xen dom0. Standard EFI Linux
Kernel infrastructure cannot be used because it requires direct
access to EFI data and code. However, in dom0 case it is not possible
because above mentioned EFI stuff is fully owned and controlled
by Xen hypervisor. In this case all calls from dom0 to EFI must
be requested via special hypercall which in turn executes relevant
EFI code in behalf of dom0.

When dom0 kernel boots it checks for EFI availability on a machine.
If it is detected then artificial EFI system table is filled.
Native EFI callas are replaced by functions which mimics them
by calling relevant hypercall. Later pointer to EFI system table
is passed to standard EFI machinery and it continues EFI subsystem
initialization taking into account that there is no direct access
to EFI boot services, runtime, tables, structures, etc. After that
system runs as usual.

This patch is based on Jan Beulich and Tang Liang work.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Tang Liang <liang.tang@oracle.com>
Signed-off-by: Daniel Kiper <daniel.kiper@oracle.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2014-07-18 21:23:58 +01:00
Linus Torvalds
59ca9ee428 Fixes:
- Fixes console deadlock when resuming PV guests
  - Fix regression hit when ballooning and resuming PV guests
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Merge tag 'stable/for-linus-3.16-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull Xen fixes from Konrad Rzeszutek Wilk:
 "Two fixes found during migration of PV guests.  David would be the one
  doing this pull but he is on vacation.

  Fixes:
   - fix console deadlock when resuming PV guests
   - fix regression hit when ballooning and resuming PV guests"

* tag 'stable/for-linus-3.16-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/balloon: set ballooned out pages as invalid in p2m
  xen/manage: fix potential deadlock when resuming the console
2014-07-17 08:02:35 -10:00
David Vrabel
438b33c714 xen/grant-table: remove support for V2 tables
Since 11c7ff17c9b6dbf3a4e4f36be30ad531a6cf0ec9 (xen/grant-table: Force
to use v1 of grants.) the code for V2 grant tables is not used.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2014-07-14 15:28:30 -04:00
David Vrabel
162e371712 x86/xen: safely map and unmap grant frames when in atomic context
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.

N.B. 'alloc_vm_area' pre-allocates the pagetable so there is no need
to worry about having to do a PGD/PUD/PMD walk (like apply_to_page_range
does) and we can instead do set_pte.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
----
[v2: Add comment about alloc_vm_area]
[v3: Fix compile error found by 0-day bot]
2014-07-14 15:28:02 -04:00
David Vrabel
fb9a0c4436 xen/balloon: set ballooned out pages as invalid in p2m
Since cd9151e26d31048b2b5e00fd02e110e07d2200c9 (xen/balloon: set a
mapping for ballooned out pages), a ballooned out page had its entry
in the p2m set to the MFN of one of the scratch pages.  This means
that the p2m will contain many entries pointing to the same MFN.

During a domain save, these many-to-one entries are not identified as
such and the scratch page is saved multiple times. On restore the
ballooned pages are populated with new frames and the domain may use
up its allocation before all pages can be restored.

Since the original fix only needed to keep a mapping for the ballooned
page it is safe to set ballooned out pages as INVALID_P2M_ENTRY in the
p2m (as they were before). Thus preventing them from being saved and
re-populated on restore.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reported-by: Marek Marczykowski <marmarek@invisiblethingslab.com>
Tested-by: Marek Marczykowski <marmarek@invisiblethingslab.com>
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Cc: <stable@vger.kernel.org>
2014-07-04 15:17:43 +01:00
David Vrabel
1b6478231c xen/manage: fix potential deadlock when resuming the console
Calling xen_console_resume() in xen_suspend() causes a warning because
it locks irq_mapping_update_lock (a mutex) and this may sleep.  If a
userspace process is using the evtchn device then this mutex may be
locked at the point of the stop_machine() call and
xen_console_resume() would then deadlock.

Resuming the console after stop_machine() returns avoids this
deadlock.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: <stable@vger.kernel.org>
2014-07-03 11:02:28 +01:00
Linus Torvalds
3d09c62394 xen: regression and PVH fixes for 3.16-rc1
- Fix dom0 PVH memory setup on latest unstable Xen releases.
 - Fix 64-bit x86 PV guest boot failure on Xen 3.1 and earlier.
 - Fix resume regression on non-PV (auto-translated physmap) guests.
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Merge tag 'stable/for-linus-3.16-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull Xen fixes from David Vrabel:
 "Xen regression and PVH fixes for 3.16-rc1

   - fix dom0 PVH memory setup on latest unstable Xen releases
   - fix 64-bit x86 PV guest boot failure on Xen 3.1 and earlier
   - fix resume regression on non-PV (auto-translated physmap) guests"

* tag 'stable/for-linus-3.16-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/grant-table: fix suspend for non-PV guests
  x86/xen: no need to explicitly register an NMI callback
  Revert "xen/pvh: Update E820 to work with PVH (v2)"
  x86/xen: fix memory setup for PVH dom0
2014-06-19 07:53:27 -10:00
David Vrabel
13cd36a37a xen/grant-table: fix suspend for non-PV guests
Commit aa8532c32216ae07c3813b9aeb774517878a7573 (xen: refactor suspend
pre/post hooks) broke resuming PVHVM (auto-translated physmap) guests.

The gnttab_suspend() would clear the mapping for the grant table
frames, but the ->unmap_frames() call is only applicable to PV guests.

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reported-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Tested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2014-06-18 10:58:01 +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
Linus Torvalds
776edb5931 Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into next
Pull core locking updates from Ingo Molnar:
 "The main changes in this cycle were:

   - reduced/streamlined smp_mb__*() interface that allows more usecases
     and makes the existing ones less buggy, especially in rarer
     architectures

   - add rwsem implementation comments

   - bump up lockdep limits"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (33 commits)
  rwsem: Add comments to explain the meaning of the rwsem's count field
  lockdep: Increase static allocations
  arch: Mass conversion of smp_mb__*()
  arch,doc: Convert smp_mb__*()
  arch,xtensa: Convert smp_mb__*()
  arch,x86: Convert smp_mb__*()
  arch,tile: Convert smp_mb__*()
  arch,sparc: Convert smp_mb__*()
  arch,sh: Convert smp_mb__*()
  arch,score: Convert smp_mb__*()
  arch,s390: Convert smp_mb__*()
  arch,powerpc: Convert smp_mb__*()
  arch,parisc: Convert smp_mb__*()
  arch,openrisc: Convert smp_mb__*()
  arch,mn10300: Convert smp_mb__*()
  arch,mips: Convert smp_mb__*()
  arch,metag: Convert smp_mb__*()
  arch,m68k: Convert smp_mb__*()
  arch,m32r: Convert smp_mb__*()
  arch,ia64: Convert smp_mb__*()
  ...
2014-06-03 12:57:53 -07:00
Linus Torvalds
9f888b3a10 xen: features and fixes for 3.16-rc0
- Support foreign mappings in PVH domains (needed when dom0 is PVH)
 
 - Fix mapping high MMIO regions in x86 PV guests (this is also the
   first half of removing the PAGE_IOMAP PTE flag).
 
 - ARM suspend/resume support.
 
 - ARM multicall support.
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Merge tag 'stable/for-linus-3.16-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip into next

Pull Xen updates from David Vrabel:
 "xen: features and fixes for 3.16-rc0
   - support foreign mappings in PVH domains (needed when dom0 is PVH)

   - fix mapping high MMIO regions in x86 PV guests (this is also the
     first half of removing the PAGE_IOMAP PTE flag).

   - ARM suspend/resume support.

   - ARM multicall support"

* tag 'stable/for-linus-3.16-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  x86/xen: map foreign pfns for autotranslated guests
  xen-acpi-processor: Don't display errors when we get -ENOSYS
  xen/pciback: Document the entry points for 'pcistub_put_pci_dev'
  xen/pciback: Document when the 'unbind' and 'bind' functions are called.
  xen-pciback: Document when we FLR an PCI device.
  xen-pciback: First reset, then free.
  xen-pciback: Cleanup up pcistub_put_pci_dev
  x86/xen: do not use _PAGE_IOMAP in xen_remap_domain_mfn_range()
  x86/xen: set regions above the end of RAM as 1:1
  x86/xen: only warn once if bad MFNs are found during setup
  x86/xen: compactly store large identity ranges in the p2m
  x86/xen: fix set_phys_range_identity() if pfn_e > MAX_P2M_PFN
  x86/xen: rename early_p2m_alloc() and early_p2m_alloc_middle()
  xen/x86: set panic notifier priority to minimum
  arm,arm64/xen: introduce HYPERVISOR_suspend()
  xen: refactor suspend pre/post hooks
  arm: xen: export HYPERVISOR_multicall to modules.
  arm64: introduce virt_to_pfn
  arm/xen: Remove definiition of virt_to_pfn in asm/xen/page.h
  arm: xen: implement multicall hypercall support.
2014-06-02 08:24:12 -07:00
Konrad Rzeszutek Wilk
1a4b50f674 xen-acpi-processor: Don't display errors when we get -ENOSYS
which is a perfectly legal error. This can be triggered if the
user has booted Xen with the no-cpuidle parameter.

Reported-by-and-Tested-by: Don Slutz <dslutz@verizon.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2014-05-23 12:34:00 -04:00
Konrad Rzeszutek Wilk
0a9fd01529 xen/pciback: Document the entry points for 'pcistub_put_pci_dev'
which are quite a few. It should be evident that dealing with that
many options is a bit complex.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
2014-05-23 12:33:55 -04:00
Konrad Rzeszutek Wilk
24d8bf1b0a xen/pciback: Document when the 'unbind' and 'bind' functions are called.
And also mention that you cannot do any pci_reset_function,
pci_reset_slot, or such calls. This is because they take the same
lock as SysFS does - and we would end up with a dead-lock if
we call those functions.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
2014-05-23 12:33:50 -04:00
Konrad Rzeszutek Wilk
8be9df6d4b xen-pciback: Document when we FLR an PCI device.
When the toolstack wants us to drop or add an PCI device it
changes the XenBus state to Configuring - and as result of that
we find out which devices we should still be exporting out and
which ones not. For the ones we don't need anymore we need to
do an PCI reset so that it is ready for the next guest.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
2014-05-23 12:33:43 -04:00
Konrad Rzeszutek Wilk
fcb8ce968f xen-pciback: First reset, then free.
We were doing the operations of freeing and reset in the wrong
order. Granted nothing broke because the reset functions just
set bar->which = 0.

But nonethless this was incorrect.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
2014-05-23 12:33:36 -04:00
Konrad Rzeszutek Wilk
8899035eec xen-pciback: Cleanup up pcistub_put_pci_dev
We are using 'psdev->dev','found_psdev->dev', and 'dev' at the
same time - and they all point to the same structure.

To keep it straight lets just use one - 'dev'.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
2014-05-23 12:33:30 -04:00
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
Linus Torvalds
619b589190 Xen bug fixes for 3.15-rc5
- Fix arm64 crash on boot.
 - Quiet a noisy arm build warning (virt_to_pfn() redefined).
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Merge tag 'stable/for-linus-3.15-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen bug fixes from David Vrabel:
 - Fix arm64 crash on boot.
 - Quiet a noisy arm build warning (virt_to_pfn() redefined).

* tag 'stable/for-linus-3.15-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  arm64: introduce virt_to_pfn
  xen/events/fifo: correctly align bitops
  arm/xen: Remove definiition of virt_to_pfn in asm/xen/page.h
2014-05-13 11:21:01 +09:00
David Vrabel
aa8532c322 xen: refactor suspend pre/post hooks
New architectures currently have to provide implementations of 5 different
functions: xen_arch_pre_suspend(), xen_arch_post_suspend(),
xen_arch_hvm_post_suspend(), xen_mm_pin_all(), and xen_mm_unpin_all().

Refactor the suspend code to only require xen_arch_pre_suspend() and
xen_arch_post_suspend().

Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
2014-05-12 17:19:56 +01:00
Vladimir Murzin
05a812ac47 xen/events/fifo: correctly align bitops
FIFO event channels require bitops on 32-bit aligned values (the event
words).  Linux's bitops require unsigned long alignment which may be
64-bits.

On arm64 an incorrectly unaligned access will fault.

Fix this by aligning the bitops along with an adjustment for bit
position and using an unsigned long for the local copy of the ready
word.

Cc: stable@vger.kernel.org
Signed-off-by: Vladimir Murzin <murzin.v@gmail.com>
Tested-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org>
Reviewed-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-04-28 11:09:40 +01:00
Peter Zijlstra
4e857c58ef arch: Mass conversion of smp_mb__*()
Mostly scripted conversion of the smp_mb__* barriers.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/n/tip-55dhyhocezdw1dg7u19hmh1u@git.kernel.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-arch@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-18 14:20:48 +02:00
Linus Torvalds
88764e0a3e Xen regression and bug fixes for 3.15-rc1.
- Fix completely broken 32-bit PV guests caused by x86 refactoring
   32-bit thread_info.
 - Only enable ticketlock slow path on Xen (not bare metal).
 - Fix two bugs with PV guests not shutting down when requested.
 - Fix a minor memory leak in xen-pciback error path.
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Merge tag 'stable/for-linus-3.15-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull Xen fixes from David Vrabel:
 "Xen regression and bug fixes for 3.15-rc1:

   - fix completely broken 32-bit PV guests caused by x86 refactoring
     32-bit thread_info.
   - only enable ticketlock slow path on Xen (not bare metal)
   - fix two bugs with PV guests not shutting down when requested
   - fix a minor memory leak in xen-pciback error path"

* tag 'stable/for-linus-3.15-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen/manage: Poweroff forcefully if user-space is not yet up.
  xen/xenbus: Avoid synchronous wait on XenBus stalling shutdown/restart.
  xen/spinlock: Don't enable them unconditionally.
  xen-pciback: silence an unwanted debug printk
  xen: fix memory leak in __xen_pcibk_add_pci_dev()
  x86/xen: Fix 32-bit PV guests's usage of kernel_stack
2014-04-17 10:54:07 -07:00
Konrad Rzeszutek Wilk
eb47f71200 xen/manage: Poweroff forcefully if user-space is not yet up.
The user can launch the guest in this sequence:

xl create -p /vm.cfg	[launch, but pause it]
xl shutdown latest	[sets control/shutdown=poweroff]
xl unpause latest
xl console latest	[and see that the guest has completely
ignored the shutdown request]

In reality the guest hasn't ignored it. It registers a watch
and gets a notification that there is value. It then calls
the shutdown_handler which ends up calling orderly_shutdown.

Unfortunately that is so early in the bootup that there
are no user-space. Which means that the orderly_shutdown fails.
But since the force flag was set to false it continues on without
reporting.

What we really want to is to use the force when we are in the
SYSTEM_BOOTING state and not use the 'force' when SYSTEM_RUNNING.

However, if we are in the running state - and the shutdown command
has been given before the user-space has been setup, there is nothing
we can do. Worst yet, we stop ignoring the 'xl shutdown' requests!

As such, the other part of this patch is to only stop ignoring
the 'xl shutdown' when we are truly in the power off sequence.

That means the user can do multiple 'xl shutdown' and we will try
to act on them instead of ignoring them.

Fixes-Bug: http://bugs.xenproject.org/xen/bug/6
Reported-by:  Alex Bligh <alex@alex.org.uk>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-04-15 17:41:29 +01:00
Konrad Rzeszutek Wilk
027bd7e899 xen/xenbus: Avoid synchronous wait on XenBus stalling shutdown/restart.
The 'read_reply' works with 'process_msg' to read of a reply in XenBus.
'process_msg' is running from within the 'xenbus' thread. Whenever
a message shows up in XenBus it is put on a xs_state.reply_list list
and 'read_reply' picks it up.

The problem is if the backend domain or the xenstored process is killed.
In which case 'xenbus' is still awaiting - and 'read_reply' if called -
stuck forever waiting for the reply_list to have some contents.

This is normally not a problem - as the backend domain can come back
or the xenstored process can be restarted. However if the domain
is in process of being powered off/restarted/halted - there is no
point of waiting on it coming back - as we are effectively being
terminated and should not impede the progress.

This patch solves this problem by checking whether the guest is the
right domain. If it is an initial domain and hurtling towards death -
there is no point of continuing the wait. All other type of guests
continue with their behavior (as Xenstore is expected to still be
running in another domain).

Fixes-Bug: http://bugs.xenproject.org/xen/bug/8
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-04-15 17:41:28 +01:00
Dan Carpenter
c0914e6166 xen-pciback: silence an unwanted debug printk
There is a missing curly brace here so we might print some extra debug
information.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
2014-04-15 17:41:12 +01:00