Only mark a page as managed when it is released back to the allocator.
This ensures that the managed page count does not get falsely increased
when a VM is running. Correspondingly change it so that pages are
marked as unmanaged after getting them from the allocator.
Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>

/proc/xen/xenbus does not work correctly.  A read blocked waiting for
a xenstore message holds the mutex needed for atomic file position
updates.  This blocks any writes on the same file handle, which can
deadlock if the write is needed to unblock the read.

Clear FMODE_ATOMIC_POS when opening this device to always get
character device like sematics.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>

Instead of requesting a new slot on the ring to the backend early, do
so only after all has been setup for the request to be sent. This
makes error handling easier as we don't need to undo the request id
allocation and ring slot allocation.
Suggested-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>

On systems with sufficiently large e820 tables, and several IOAPICs, it
is possible for the XENMEM_machine_memory_map callback (and its
counterpart, XENMEM_memory_map) to attempt to return an e820 table with
more than 128 entries.  This callback adds entries to the BIOS-provided
e820 table to account for IOAPIC registers, which, on sufficiently large
systems, can result in an e820 table that is too large to copy back into
xen_e820_map.

This change simply increases the size of xen_e820_map to E820_X_MAX to
ensure that there is enough room to store the entire e820 map returned
from this callback.
Signed-off-by: Alex Thorlton <athorlton@sgi.com>
Suggested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Juergen Gross <jgross@suse.com>

It's really not necessary to limit E820_X_MAX to 128 in the non-EFI
case.  This commit drops E820_X_MAX's dependency on CONFIG_EFI, so that
E820_X_MAX is always at least slightly larger than E820MAX.

The real motivation behind this is actually to prevent some issues in
the Xen kernel, where the XENMEM_machine_memory_map hypercall can
produce an e820 map larger than 128 entries, even on systems where the
original e820 table was quite a bit smaller than that, depending on how
many IOAPICs are installed on the system.
Signed-off-by: Alex Thorlton <athorlton@sgi.com>
Suggested-by: Ingo Molnar <mingo@redhat.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Juergen Gross <jgross@suse.com>

The function is never called under PV guests, and only shows up
when MSI (or MSI-X) cannot be allocated. Convert the message
to include the error value.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>

Variable err is initialized with 0. As a result, the return value may
be 0 even if get_zeroed_page() fails to allocate memory. This patch fixes
the bug, initializing err with "-ENOMEM".
Signed-off-by: Pan Bian <bianpan2016@163.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>

Variable rc is reset in the loop, and its value will be non-negative
during the second and after repeat of the loop. If it fails to allocate
memory then, it may return a non-negative integer, which indicates no
error. This patch fixes the bug, assigning "-ENOMEM" to rc when
kzalloc() or alloc_page() returns NULL, and removing the initialization
of rc outside of the loop.
Signed-off-by: Pan Bian <bianpan2016@163.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>

The function xen_guest_init is using __alloc_percpu with an alignment
which are not power of two.

However, the percpu allocator never supported alignments which are not power
of two and has always behaved incorectly in thise case.

Commit 3ca45a46 "percpu: ensure requested alignment is power of two"
introduced a check which trigger a warning [1] when booting linux-next
on Xen. But in reality this bug was always present.

This can be fixed by replacing the call to __alloc_percpu with
alloc_percpu. The latter will use an alignment which are a power of two.

[1]

[    0.023921] illegal size (48) or align (48) for percpu allocation
[    0.024167] ------------[ cut here ]------------
[    0.024344] WARNING: CPU: 0 PID: 1 at linux/mm/percpu.c:892 pcpu_alloc+0x88/0x6c0
[    0.024584] Modules linked in:
[    0.024708]
[    0.024804] CPU: 0 PID: 1 Comm: swapper/0 Not tainted
4.9.0-rc7-next-20161128 #473
[    0.025012] Hardware name: Foundation-v8A (DT)
[    0.025162] task: ffff80003d870000 task.stack: ffff80003d844000
[    0.025351] PC is at pcpu_alloc+0x88/0x6c0
[    0.025490] LR is at pcpu_alloc+0x88/0x6c0
[    0.025624] pc : [<ffff00000818e678>] lr : [<ffff00000818e678>]
pstate: 60000045
[    0.025830] sp : ffff80003d847cd0
[    0.025946] x29: ffff80003d847cd0 x28: 0000000000000000
[    0.026147] x27: 0000000000000000 x26: 0000000000000000
[    0.026348] x25: 0000000000000000 x24: 0000000000000000
[    0.026549] x23: 0000000000000000 x22: 00000000024000c0
[    0.026752] x21: ffff000008e97000 x20: 0000000000000000
[    0.026953] x19: 0000000000000030 x18: 0000000000000010
[    0.027155] x17: 0000000000000a3f x16: 00000000deadbeef
[    0.027357] x15: 0000000000000006 x14: ffff000088f79c3f
[    0.027573] x13: ffff000008f79c4d x12: 0000000000000041
[    0.027782] x11: 0000000000000006 x10: 0000000000000042
[    0.027995] x9 : ffff80003d847a40 x8 : 6f697461636f6c6c
[    0.028208] x7 : 6120757063726570 x6 : ffff000008f79c84
[    0.028419] x5 : 0000000000000005 x4 : 0000000000000000
[    0.028628] x3 : 0000000000000000 x2 : 000000000000017f
[    0.028840] x1 : ffff80003d870000 x0 : 0000000000000035
[    0.029056]
[    0.029152] ---[ end trace 0000000000000000 ]---
[    0.029297] Call trace:
[    0.029403] Exception stack(0xffff80003d847b00 to
                               0xffff80003d847c30)
[    0.029621] 7b00: 0000000000000030 0001000000000000
ffff80003d847cd0 ffff00000818e678
[    0.029901] 7b20: 0000000000000002 0000000000000004
ffff000008f7c060 0000000000000035
[    0.030153] 7b40: ffff000008f79000 ffff000008c4cd88
ffff80003d847bf0 ffff000008101778
[    0.030402] 7b60: 0000000000000030 0000000000000000
ffff000008e97000 00000000024000c0
[    0.030647] 7b80: 0000000000000000 0000000000000000
0000000000000000 0000000000000000
[    0.030895] 7ba0: 0000000000000035 ffff80003d870000
000000000000017f 0000000000000000
[    0.031144] 7bc0: 0000000000000000 0000000000000005
ffff000008f79c84 6120757063726570
[    0.031394] 7be0: 6f697461636f6c6c ffff80003d847a40
0000000000000042 0000000000000006
[    0.031643] 7c00: 0000000000000041 ffff000008f79c4d
ffff000088f79c3f 0000000000000006
[    0.031877] 7c20: 00000000deadbeef 0000000000000a3f
[    0.032051] [<ffff00000818e678>] pcpu_alloc+0x88/0x6c0
[    0.032229] [<ffff00000818ece8>] __alloc_percpu+0x18/0x20
[    0.032409] [<ffff000008d9606c>] xen_guest_init+0x174/0x2f4
[    0.032591] [<ffff0000080830f8>] do_one_initcall+0x38/0x130
[    0.032783] [<ffff000008d90c34>] kernel_init_freeable+0xe0/0x248
[    0.032995] [<ffff00000899a890>] kernel_init+0x10/0x100
[    0.033172] [<ffff000008082ec0>] ret_from_fork+0x10/0x50
Reported-by: Wei Chen <wei.chen@arm.com>
Link: https://lkml.org/lkml/2016/11/28/669Signed-off-by: Julien Grall <julien.grall@arm.com>
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Cc: stable@vger.kernel.org

ARM and arm64 Xen ports share a number of headers, leading to
packaging issues when these headers needs to be exported, as it
breaks the reasonable requirement that an architecture port
has self-contained headers.

Fix the issue by moving the 5 header files to include/xen/arm,
and keep local placeholders to include the relevant files.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>

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>

Commit 9c17d965 ("xen/gntdev: Grant maps should not be subject to
NUMA balancing") set VM_IO flag to prevent grant maps from being
subjected to NUMA balancing.

It was discovered recently that this flag causes get_user_pages() to
always fail with -EFAULT.

check_vma_flags
__get_user_pages
__get_user_pages_locked
__get_user_pages_unlocked
get_user_pages_fast
iov_iter_get_pages
dio_refill_pages
do_direct_IO
do_blockdev_direct_IO
do_blockdev_direct_IO
ext4_direct_IO_read
generic_file_read_iter
aio_run_iocb

(which can happen if guest's vdisk has direct-io-safe option).

To avoid this let's use VM_MIXEDMAP flag instead --- it prevents
NUMA balancing just as VM_IO does and has no effect on
check_vma_flags().

Cc: stable@vger.kernel.org
Reported-by: Olaf Hering <olaf@aepfle.de>
Suggested-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: Hugh Dickins <hughd@google.com>
Tested-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Juergen Gross <jgross@suse.com>

Most error branches following the call to kmalloc contain
a call to kfree. This patch add these calls where they are
missing.

This issue was found with Hector.
Signed-off-by: Quentin Lambert <lambert.quentin@gmail.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>

I am no longer in a postion to be a maintainer of the Xen subsystem.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Acked-by: Juergen Gross <jgross@suse.com>
Acked-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>

Mounting proc in user namespace containers fails if the xenbus
filesystem is mounted on /proc/xen because this directory fails
the "permanently empty" test. proc_create_mount_point() exists
specifically to create such mountpoints in proc but is currently
proc-internal. Export this interface to modules, then use it in
xenbus when creating /proc/xen.
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Juergen Gross <jgross@suse.com>

Use builtin_pci_driver() helper to simplify the code.
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>

The connect function prints an unintialized error code after an
earlier initialization was removed:

drivers/net/xen-netback/xenbus.c: In function 'connect':
drivers/net/xen-netback/xenbus.c:938:3: error: 'err' may be used uninitialized in this function [-Werror=maybe-uninitialized]

This prints it as -EINVAL instead, which seems to be the most
appropriate error code. Before the patch that caused the warning,
this would print a positive number returned by vsscanf() instead,
which is also wrong. We probably don't need a backport though,
as fixing the warning here should be sufficient.

Fixes: f95842e7 ("xen: make use of xenbus_read_unsigned() in xen-netback")
Fixes: 8d3d53b3 ("xen-netback: Add support for multiple queues")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Signed-off-by: Juergen Gross <jgross@suse.com>

Use xenbus_read_unsigned() instead of xenbus_scanf() when possible.
This requires to change the type of the reads from int to unsigned,
but these cases have been wrong before: negative values are not allowed
for the modified cases.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: David Vrabel <david.vrabel@citrix.com>

Use xenbus_read_unsigned() instead of xenbus_scanf() when possible.
This requires to change the type of the read from int to unsigned,
but this case has been wrong before: negative values are not allowed
for the modified case.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: David Vrabel <david.vrabel@citrix.com>

Use xenbus_read_unsigned() instead of xenbus_scanf() when possible.
This requires to change the type of the reads from int to unsigned,
but these cases have been wrong before: negative values are not allowed
for the modified cases.

Cc: tomi.valkeinen@ti.com
Cc: linux-fbdev@vger.kernel.org
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: David Vrabel <david.vrabel@citrix.com>

Use xenbus_read_unsigned() instead of xenbus_scanf() when possible.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: David Vrabel <david.vrabel@citrix.com>

Use xenbus_read_unsigned() instead of xenbus_scanf() when possible.
This requires to change the type of the read from int to unsigned,
but this case has been wrong before: negative values are not allowed
for the modified case.

Cc: bhelgaas@google.com
Cc: linux-pci@vger.kernel.org
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: David Vrabel <david.vrabel@citrix.com>

Use xenbus_read_unsigned() instead of xenbus_scanf() when possible.
This requires to change the type of some reads from int to unsigned,
but these cases have been wrong before: negative values are not allowed
for the modified cases.

Cc: netdev@vger.kernel.org
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: David Vrabel <david.vrabel@citrix.com>

Use xenbus_read_unsigned() instead of xenbus_scanf() when possible.
This requires to change the type of some reads from int to unsigned,
but these cases have been wrong before: negative values are not allowed
for the modified cases.

Cc: wei.liu2@citrix.com
Cc: paul.durrant@citrix.com
Cc: netdev@vger.kernel.org
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: David Vrabel <david.vrabel@citrix.com>

Use xenbus_read_unsigned() instead of xenbus_scanf() when possible.
This requires to change the type of the reads from int to unsigned,
but these cases have been wrong before: negative values are not allowed
for the modified cases.

Cc: dmitry.torokhov@gmail.com
Cc: linux-input@vger.kernel.org
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: David Vrabel <david.vrabel@citrix.com>

Use xenbus_read_unsigned() instead of xenbus_scanf() when possible.
This requires to change the type of one read from int to unsigned,
but this case has been wrong before: negative values are not allowed
for the modified case.

Cc: peterhuewe@gmx.de
Cc: tpmdd@selhorst.net
Cc: jarkko.sakkinen@linux.intel.com
Cc: jgunthorpe@obsidianresearch.com
Cc: tpmdd-devel@lists.sourceforge.net
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Acked-by: David Vrabel <david.vrabel@citrix.com>

Use xenbus_read_unsigned() instead of xenbus_scanf() when possible.
This requires to change the type of some reads from int to unsigned,
but these cases have been wrong before: negative values are not allowed
for the modified cases.

Cc: konrad.wilk@oracle.com
Cc: roger.pau@citrix.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: David Vrabel <david.vrabel@citrix.com>

Use xenbus_read_unsigned() instead of xenbus_scanf() when possible.
This requires to change the type of one read from int to unsigned,
but this case has been wrong before: negative values are not allowed
for the modified case.

Cc: konrad.wilk@oracle.com
Cc: roger.pau@citrix.com
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: David Vrabel <david.vrabel@citrix.com>

There are multiple instances of code reading an optional unsigned
parameter from Xenstore via xenbus_scanf(). Instead of repeating the
same code over and over add a service function doing the job.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: David Vrabel <david.vrabel@citrix.com>

Pull i2c fix from Wolfram Sang:
 "A bugfix for the I2C core fixing a (rare) race condition"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: core: fix NULL pointer dereference under race condition

Merge branches 'sched-urgent-for-linus' and 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull stack vmap fixups from Thomas Gleixner:
 "Two small patches related to sched_show_task():

   - make sure to hold a reference on the task stack while accessing it

   - remove the thread_saved_pc printout

  .. and add a sanity check into release_task_stack() to catch problems
  with task stack references"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/core: Remove pointless printout in sched_show_task()
  sched/core: Fix oops in sched_show_task()

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  fork: Add task stack refcounting sanity check and prevent premature task stack freeing

Pull MD fixes from Shaohua Li:
 "There are several bug fixes queued:

   - fix raid5-cache recovery bugs

   - fix discard IO error handling for raid1/10

   - fix array sync writes bogus position to superblock

   - fix IO error handling for raid array with external metadata"

* tag 'md/4.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md:
  md: be careful not lot leak internal curr_resync value into metadata. -- (all)
  raid1: handle read error also in readonly mode
  raid5-cache: correct condition for empty metadata write
  md: report 'write_pending' state when array in sync
  md/raid5: write an empty meta-block when creating log super-block
  md/raid5: initialize next_checkpoint field before use
  RAID10: ignore discard error
  RAID1: ignore discard error

Pull SCSI fixes from James Bottomley:
 "Two more important data integrity fixes related to RAID device drivers
  which wrongly throw away the SYNCHRONIZE CACHE command in the non-RAID
  path and a memory leak in the scsi_debug driver"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: arcmsr: Send SYNCHRONIZE_CACHE command to firmware
  scsi: scsi_debug: Fix memory leak if LBP enabled and module is unloaded
  scsi: megaraid_sas: Fix data integrity failure for JBOD (passthrough) devices

Pull input subsystem updates from Dmitry Torokhov.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: psmouse - cleanup Focaltech code
  Input: i8042 - add XMG C504 to keyboard reset table

Pull FireWire (IEEE 1394) fixes from Stefan Richter:

 - add missing input validation to the firewire-net driver. Invalid
   IP-over-1394 encapsulation headers could trigger buffer overflows
   (CVE 2016-8633).

 - IP-over-1394 link fragmentation headers were read and written
   incorrectly, breaking fragmented RX/TX with other OS's stacks.

* tag 'firewire-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394:
  firewire: net: fix fragmented datagram_size off-by-one
  firewire: net: guard against rx buffer overflows

Pull media fixes from Mauro Carvalho Chehab:
 "A series of fixup patches meant to fix the usage of DMA on stack, plus
  one warning fixup"

* tag 'media/v4.9-3' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (32 commits)
  [media] radio-bcm2048: don't ignore errors
  [media] pctv452e: fix semicolon.cocci warnings
  [media] flexcop-usb: don't use stack for DMA
  [media] stk-webcam: don't use stack for DMA
  [media] s2255drv: don't use stack for DMA
  [media] cpia2_usb: don't use stack for DMA
  [media] digitv: handle error code on RC query
  [media] dw2102: return error if su3000_power_ctrl() fails
  [media] nova-t-usb2: handle error code on RC query
  [media] technisat-usb2: use DMA buffers for I2C transfers
  [media] pctv452e: don't call BUG_ON() on non-fatal error
  [media] pctv452e: don't do DMA on stack
  [media] nova-t-usb2: don't do DMA on stack
  [media] gp8psk: don't go past the buffer size
  [media] gp8psk: don't do DMA on stack
  [media] dtv5100: don't do DMA on stack
  [media] dtt200u: handle USB control message errors
  [media] dtt200u: don't do DMA on stack
  [media] dtt200u-fe: handle errors on USB control messages
  [media] dtt200u-fe: don't do DMA on stack
  ...

Pull PCI fixes from Bjorn Helgaas:

 - fix for a Qualcomm driver issue that causes a use-before-set crash

 - fix for DesignWare iATU unroll support that causes external aborts
   when enabling the host bridge

* tag 'pci-v4.9-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
  PCI: designware: Check for iATU unroll support after initializing host
  PCI: qcom: Fix pp->dev usage before assignment

Pull MTD fixes from Brian Norris:

 - MAINTAINERS updates to reflect some new maintainers/submaintainers.

   We have some great volunteers who've been developing and reviewing
   already. We're going to try a group maintainership model, so
   eventually you'll probably see pull requests from people besides me.

 - NAND fixes from Boris:
    "Three simple fixes:

      - fix a non-critical bug in the gpmi driver
      - fix a bug in the 'automatic NAND timings selection' feature
        introduced in 4.9-rc1
      - fix a false positive uninitialized-var warning"

* tag 'for-linus-20161104' of git://git.infradead.org/linux-mtd:
  mtd: mtk: avoid warning in mtk_ecc_encode
  mtd: nand: Fix data interface configuration logic
  mtd: nand: gpmi: disable the clocks on errors
  MAINTAINERS: add more people to the MTD maintainer team
  MAINTAINERS: add a maintainer for the SPI NOR subsystem

Pull MMC fixes from Ulf Hansson:
 "MMC host:

   - sdhci-msm: Fix error path in probe
   - dw_mmc-pltfm: Avoid NULL pointer dereference"

* tag 'mmc-v4.9-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc:
  mmc: sdhci-msm: Fix error return code in sdhci_msm_probe()
  mmc: dw_mmc-pltfm: fix the potential NULL pointer dereference