The PCI pool API is deprecated. This commit replaces the PCI pool old
API by the appropriate function with the DMA pool API.
Signed-off-by: Romain Perier <romain.perier@collabora.com>
Acked-by: Peter Senna Tschudin <peter.senna@collabora.com>
Tested-by: Peter Senna Tschudin <peter.senna@collabora.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

Limit PDMA send to 512 B to avoid data corruption on DTC3181E. The
corruption is always the same: one byte missing at the beginning of a
128 B block. It happens only with slow Quantum LPS 240 drive, not with
faster IBM DORS-32160. It's not clear what causes this. Documentation
for the DTC436 chip has not been made available.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

The polling loops in pread() and pwrite() can easily become infinite
loops and hang the machine.

Merge the IRQ check into host buffer wait loop and add polling limit.

Also place a limit on polling for 53C80 registers accessibility.

[Use NCR5380_poll_politely2() for register polling. Rely on polling for
gated IRQ rather than polling for phase error, like the algorithm in the
53c400 datasheet. Move DTC436 workarounds into a separate patch.
Factor-out common code as wait_for_53c80_access(). Rework the residual
calculations. -- F.T.]
Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

The word "read" may be used to mean "DMA read operation" or "SCSI READ
command", though a READ command implies writing to memory.
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

When an IRQ arrives during PDMA transfer, pread() and pwrite() return
without waiting for the 53C80 registers to be ready and this ends up
messing up the chip state. This was observed with SONY CDU-55S which is
slow enough to disconnect during 4096-byte reads.

IRQ during PDMA is not an error so don't return -1. Instead, store the
remaining byte count for use by NCR5380_dma_residual().

[Poll for the BASR_END_DMA_TRANSFER condition rather than remove the
error message -- F.T.]
Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

generic_NCR5380_dma_xfer_len() incorrectly uses cmd->transfersize which
causes rescan-scsi-bus and CD-ROM access to hang the system.  Use
cmd->SCp.this_residual instead, like other NCR5380 drivers.
Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Tested-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

When issuing a bus reset we should complete all commands, not
just the command triggering the reset.
Signed-off-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Raghava Aditya Renukunta  <RaghavaAditya.Renukunta@microsemi.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

To correctly identify which fib has a scsi command callback this
patch implements a flag FIB_CONTEXT_FLAG_SCSI_CMD.
Signed-off-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Raghava Aditya Renukunta  <RaghavaAditya.Renukunta@microsemi.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

aac_hba_send() will return FAILED for any non-SCSI command requests,
failing any TMFs. This patch updates the check to allow TMFs.
Signed-off-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Raghava Aditya Renukunta  <RaghavaAditya.Renukunta@microsemi.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

When sending a reset fib we shouldn't rely on the scsi command,
but rather set the TMF status in the map_info->reset_state variable.
That allows us to send a TMF independent on a scsi command.
Signed-off-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Raghava Aditya Renukunta  <RaghavaAditya.Renukunta@microsemi.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

Split off device, target, and bus reset functionality into
individual functions.
Signed-off-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Raghava Aditya Renukunta  <RaghavaAditya.Renukunta@microsemi.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

Split off the host reset parts of aac_eh_reset() into a separate
host reset function.
Signed-off-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Raghava Aditya Renukunta  <RaghavaAditya.Renukunta@microsemi.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

Split off reset FIB generation into separate functions.
Signed-off-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Raghava Aditya Renukunta  <RaghavaAditya.Renukunta@microsemi.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

Pull x86 platform driver fix from Darren Hart:
 "Fix loop preventing some platforms from waking up via the power button
  in s2idle:

   - intel-vbtn: match power button on press rather than release"

* tag 'platform-drivers-x86-v4.13-4' of git://git.infradead.org/linux-platform-drivers-x86:
  platform/x86: intel-vbtn: match power button on press rather than release

Pull ext4 fixes from Ted Ts'o:
 "A large number of ext4 bug fixes and cleanups for v4.13"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: fix copy paste error in ext4_swap_extents()
  ext4: fix overflow caused by missing cast in ext4_resize_fs()
  ext4, project: expand inode extra size if possible
  ext4: cleanup ext4_expand_extra_isize_ea()
  ext4: restructure ext4_expand_extra_isize
  ext4: fix forgetten xattr lock protection in ext4_expand_extra_isize
  ext4: make xattr inode reads faster
  ext4: inplace xattr block update fails to deduplicate blocks
  ext4: remove unused mode parameter
  ext4: fix warning about stack corruption
  ext4: fix dir_nlink behaviour
  ext4: silence array overflow warning
  ext4: fix SEEK_HOLE/SEEK_DATA for blocksize < pagesize
  ext4: release discard bio after sending discard commands
  ext4: convert swap_inode_data() over to use swap() on most of the fields
  ext4: error should be cleared if ea_inode isn't added to the cache
  ext4: Don't clear SGID when inheriting ACLs
  ext4: preserve i_mode if __ext4_set_acl() fails
  ext4: remove unused metadata accounting variables
  ext4: correct comment references to ext4_ext_direct_IO()

Pull MIPS fixes from Ralf Baechle:
 "This fixes two build issues for ralink platforms, both due to missing
  #includes which used to be included indirectly via other headers"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
  MIPS: ralink: mt7620: Add missing header
  MIPS: ralink: Fix build error due to missing header

The latest change of compat_sys_sigpending in commit 8f13621a
("sigpending(): move compat to native") has broken it in two ways.

First, it tries to write 4 bytes more than userspace expects:
sizeof(old_sigset_t) == sizeof(long) == 8 instead of
sizeof(compat_old_sigset_t) == sizeof(u32) == 4.

Second, on big endian architectures these bytes are being written in the
wrong order.

This bug was found by strace test suite.
Reported-by: Anatoly Pugachev <matorola@gmail.com>
Inspired-by: Eugene Syromyatnikov <evgsyr@gmail.com>
Fixes: 8f13621a ("sigpending(): move compat to native")
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This bug was found by a static code checker tool for copy paste
problems.
Signed-off-by: Maninder Singh <maninder1.s@samsung.com>
Signed-off-by: Vaneet Narang <v.narang@samsung.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

On a 32-bit platform, the value of n_blcoks_count may be wrong during
the file system is resized to size larger than 2^32 blocks.  This may
caused the superblock being corrupted with zero blocks count.

Fixes: 1c6bd717Signed-off-by: Jerry Lee <jerrylee@qnap.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org # 3.7+

When upgrading from old format, try to set project id
to old file first time, it will return EOVERFLOW, but if
that file is dirtied(touch etc), changing project id will
be allowed, this might be confusing for users, we could
try to expand @i_extra_isize here too.
Reported-by: Zhang Yi <yi.zhang@huawei.com>
Signed-off-by: Miao Xie <miaoxie@huawei.com>
Signed-off-by: Wang Shilong <wshilong@ddn.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Clean up some goto statement, make ext4_expand_extra_isize_ea() clearer.
Signed-off-by: Miao Xie <miaoxie@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Wang Shilong <wshilong@ddn.com>

Current ext4_expand_extra_isize just tries to expand extra isize, if
someone is holding xattr lock or some check fails, it will give up.
So rename its name to ext4_try_to_expand_extra_isize.

Besides that, we clean up unnecessary check and move some relative checks
into it.
Signed-off-by: Miao Xie <miaoxie@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Wang Shilong <wshilong@ddn.com>

We should avoid the contention between the i_extra_isize update and
the inline data insertion, so move the xattr trylock in front of
i_extra_isize update.
Signed-off-by: Miao Xie <miaoxie@huawei.com>
Reviewed-by: Wang Shilong <wshilong@ddn.com>

ext4_xattr_inode_read() currently reads each block sequentially while
waiting for io operation to complete before moving on to the next
block. This prevents request merging in block layer.

Add a ext4_bread_batch() function that starts reads for all blocks
then optionally waits for them to complete. A similar logic is used
in ext4_find_entry(), so update that code to use the new function.
Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

When an xattr block has a single reference, block is updated inplace
and it is reinserted to the cache. Later, a cache lookup is performed
to see whether an existing block has the same contents. This cache
lookup will most of the time return the just inserted entry so
deduplication is not achieved.

Running the following test script will produce two xattr blocks which
can be observed in "File ACL: " line of debugfs output:

  mke2fs -b 1024 -I 128 -F -O extent /dev/sdb 1G
  mount /dev/sdb /mnt/sdb

  touch /mnt/sdb/{x,y}

  setfattr -n user.1 -v aaa /mnt/sdb/x
  setfattr -n user.2 -v bbb /mnt/sdb/x

  setfattr -n user.1 -v aaa /mnt/sdb/y
  setfattr -n user.2 -v bbb /mnt/sdb/y

  debugfs -R 'stat x' /dev/sdb | cat
  debugfs -R 'stat y' /dev/sdb | cat

This patch defers the reinsertion to the cache so that we can locate
other blocks with the same contents.
Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>

ext4_alloc_file_blocks() does not use its mode parameter. Remove it.
Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

After commit 62d1034f53e3 ("fortify: use WARN instead of BUG for now"),
we get a warning about possible stack overflow from a memcpy that
was not strictly bounded to the size of the local variable:

    inlined from 'ext4_mb_seq_groups_show' at fs/ext4/mballoc.c:2322:2:
include/linux/string.h:309:9: error: '__builtin_memcpy': writing between 161 and 1116 bytes into a region of size 160 overflows the destination [-Werror=stringop-overflow=]

We actually had a bug here that would have been found by the warning,
but it was already fixed last year in commit 30a9d7af ("ext4: fix
stack memory corruption with 64k block size").

This replaces the fixed-length structure on the stack with a variable-length
structure, using the correct upper bound that tells the compiler that
everything is really fine here. I also change the loop count to check
for the same upper bound for consistency, but the existing code is
already correct here.

Note that while clang won't allow certain kinds of variable-length arrays
in structures, this particular instance is fine, as the array is at the
end of the structure, and the size is strictly bounded.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

The dir_nlink feature has been enabled by default for new ext4
filesystems since e2fsprogs-1.41 in 2008, and was automatically
enabled by the kernel for older ext4 filesystems since the
dir_nlink feature was added with ext4 in kernel 2.6.28+ when
the subdirectory count exceeded EXT4_LINK_MAX-1.

Automatically adding the file system features such as dir_nlink is
generally frowned upon, since it could cause the file system to not be
mountable on older kernel, thus preventing the administrator from
rolling back to an older kernel if necessary.

In this case, the administrator might also want to disable the feature
because glibc's fts_read() function does not correctly optimize
directory traversal for directories that use st_nlinks field of 1 to
indicate that the number of links in the directory are not tracked by
the file system, and could fail to traverse the full directory
hierarchy.  Fortunately, in the past ten years very few users have
complained about incomplete file system traversal by glibc's
fts_read().

This commit also changes ext4_inc_count() to allow i_nlinks to reach
the full EXT4_LINK_MAX links on the parent directory (including "."
and "..") before changing i_links_count to be 1.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=196405Signed-off-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

I get a static checker warning:

    fs/ext4/ext4.h:3091 ext4_set_de_type()
    error: buffer overflow 'ext4_type_by_mode' 15 <= 15

It seems unlikely that we would hit this read overflow in real life, but
it's also simple enough to make the array 16 bytes instead of 15.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

ext4_find_unwritten_pgoff() does not properly handle a situation when
starting index is in the middle of a page and blocksize < pagesize. The
following command shows the bug on filesystem with 1k blocksize:

  xfs_io -f -c "falloc 0 4k" \
            -c "pwrite 1k 1k" \
            -c "pwrite 3k 1k" \
            -c "seek -a -r 0" foo

In this example, neither lseek(fd, 1024, SEEK_HOLE) nor lseek(fd, 2048,
SEEK_DATA) will return the correct result.

Fix the problem by neglecting buffers in a page before starting offset.
Reported-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
CC: stable@vger.kernel.org # 3.8+

This fixes a problem where the system gets stuck in a loop
unable to wakeup via power button in s2idle.

The problem happens because:
 - press power button:
   - system emits 0xc0 (power press), event ignored
   - system emits 0xc1 (power release), event processed,
     emited as KEY_POWER
   - set wakeup_mode to true
   - system goes to s2idle
 - press power button
   - system emits 0xc0 (power press), wakeup_mode is true,
     system wakes
   - system emits 0xc1 (power release), event processed,
     emited as KEY_POWER
   - system goes to s2idle again

To avoid this situation, process the presses (which matches what
intel-hid does too).

Verified on an Dell XPS 9365
Signed-off-by: Mario Limonciello <mario.limonciello@dell.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>

Pull media fixes from Mauro Carvalho Chehab:
 "This series is larger than I would like to submit for -rc4. My
  original intent were to sent it to either -rc2 or -rc3. Unfortunately,
  due to my vacations, I got a lot of pending stuff after my return, and
  had to do some biz trips, with prevented me to send this earlier.

  Several fixes:

   - some fixes at atomisp staging driver

   - several gcc 7 warning fixes

   - cleanup media SVG files, in order to fix PDF build on some distros

   - fix random Kconfig build of venus driver

   - some fixes for the venus driver

   - some changes from semaphone to mutex in ngene's driver

   - some locking fixes at dib0700 driver

   - several fixes on ngene's driver and frontends to make it properly
     support some new boards added on Kernel 4.13

   - some fixes to CEC drivers

   - omap_vout: vrfb: convert to dmaengine

   - docs-rst: document EBUSY for VIDIOC_S_FMT

  Please notice that the big diffstat changes here are at the SVG files.

  Visually, the images look the same, but the file size is now a lot
  smaller than before, and they don't use some XML tags that would cause
  them to be badly parsed by some ImageMagick versions, or to require a
  lot of memory by TeTex, with would break PDF output on some
  distributions"

* tag 'media/v4.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (68 commits)
  media: atomisp2: array underflow in imx_enum_frame_size()
  media: atomisp2: array underflow in ap1302_enum_frame_size()
  media: atomisp2: Array underflow in atomisp_enum_input()
  media: platform: davinci: drop VPFE_CMD_S_CCDC_RAW_PARAMS
  media: platform: davinci: return -EINVAL for VPFE_CMD_S_CCDC_RAW_PARAMS ioctl
  media: venus: don't abuse dma_alloc for non-DMA allocations
  media: venus: hfi: fix error handling in hfi_sys_init_done()
  media: venus: fix compile-test build on non-qcom ARM platform
  media: venus: mark PM functions as __maybe_unused
  media: cec-notifier: small improvements
  media: pulse8-cec: persistent_config should be off by default
  media: cec: cec_transmit_attempt_done: ignore CEC_TX_STATUS_MAX_RETRIES
  media: staging: atomisp: array underflow in ioctl
  media: lirc: LIRC_GET_REC_RESOLUTION should return microseconds
  media: svg: avoid too long lines
  media: svg files: simplify files
  media: selection.svg: simplify the SVG file
  media: vimc: set id_table for platform drivers
  media: staging: atomisp: disable warnings with cc-disable-warning
  media: davinci: variable 'common' set but not used
  ...

We've changed the discard command handling into parallel manner.
But, in this change, I forgot decreasing the usage count of the bio
which was used to send discard request. I'm sorry about that.

Fixes: a0154344 ("ext4: send parallel discards on commit completions")
Signed-off-by: Daeho Jeong <daeho.jeong@samsung.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>

Pull GPIO fixes from Linus Walleij:

 - LP87565: set the proper output level for direction_output.

 - stm32: fix the kernel build by selecting the hierarchical irqdomain
   symbol properly - this happens to be done in the pin control
   framework but whatever, it had dependencies to GPIO so we need to
   apply it here.

 - Select the hierarchical IRQ domain also for Xgene.

 - Fix wakeups to work on MXC.

 - Fix up the device tree binding on Exar that went astray, also add the
   right bindings.

 - Fix the unwanted events for edges from the library.

 - Fix the unbalanced chanined IRQ on the Tegra.

* tag 'gpio-v4.13-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
  gpio: tegra: fix unbalanced chained_irq_enter/exit
  gpiolib: skip unwanted events, don't convert them to opposite edge
  gpio: exar: Use correct property prefix and document bindings
  gpio: gpio-mxc: Fix: higher 16 GPIOs usable as wake source
  gpio: xgene-sb: select IRQ_DOMAIN_HIERARCHY
  pinctrl: stm32: select IRQ_DOMAIN_HIERARCHY instead of depends on
  gpio: lp87565: Set proper output level and direction for direction_output
  MAINTAINERS: Add entry for Whiskey Cove PMIC GPIO driver

Pull clk fixes from Stephen Boyd:
 "A handful of critical fixes for changes introduce this merge window.

   - The TI sci_clk_get() API was pretty broken and nobody noticed.

   - There were some CPUfreq crashes on C.H.I.P devices because we
     failed to propagate rates up the clk tree.

   - Also, the Intel Atom PMC clk driver needs to mark a clk critical if
     the firmware has it enabled already so that audio doesn't get
     killed on Baytrail.

   - Gemini devices have a dead serial console because the reset control
     usage in the serial driver assume one method of reset that gemini
     doesn't support (this will be fixed in the next version in the
     reset framework so this is the small fix for -rc series).

   - Finally we have two rate calculation fixes, one for Exynos and one
     for Meson SoCs, that fix rate inconsistencies"

* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
  clk: keystone: sci-clk: Fix sci_clk_get
  clk: meson: mpll: fix mpll0 fractional part ignored
  clk: samsung: exynos5420: The EPLL rate table corrections
  clk: sunxi-ng: sun5i: Add clk_set_rate_parent to the CPU clock
  clk: x86: Do not gate clocks enabled by the firmware
  clk: gemini: Fix reset regression

Pull KVM fixes from Radim Krčmář:
 "ARM:

   - Yet another race with VM destruction plugged

   - A set of small vgic fixes

  x86:

   - Preserve pending INIT

   - RCU fixes in paravirtual async pf, VM teardown, and VMXOFF
     emulation

   - nVMX interrupt injection and dirty tracking fixes

   - initialize to make UBSAN happy"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: arm/arm64: vgic: Use READ_ONCE fo cmpxchg
  KVM: nVMX: Fix interrupt window request with "Acknowledge interrupt on exit"
  KVM: nVMX: mark vmcs12 pages dirty on L2 exit
  kvm: nVMX: don't flush VMCS12 during VMXOFF or VCPU teardown
  KVM: nVMX: do not pin the VMCS12
  KVM: avoid using rcu_dereference_protected
  KVM: X86: init irq->level in kvm_pv_kick_cpu_op
  KVM: X86: Fix loss of pending INIT due to race
  KVM: async_pf: make rcu irq exit if not triggered from idle task
  KVM: nVMX: fixes to nested virt interrupt injection
  KVM: nVMX: do not fill vm_exit_intr_error_code in prepare_vmcs12
  KVM: arm/arm64: Handle hva aging while destroying the vm
  KVM: arm/arm64: PMU: Fix overflow interrupt injection
  KVM: arm/arm64: Fix bug in advertising KVM_CAP_MSI_DEVID capability

Pull x86 fix from Thomas Gleixner:
 "The recent irq core changes unearthed API abuse in the HPET code,
  which manifested itself in a suspend/resume regression.

  The fix replaces the cruft with the proper function calls and cures
  the regression"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/hpet: Cure interface abuse in the resume path

Pull timer fix from Thomas Gleixner:
 "A single fix for a multiplication overflow in the timer code on 32bit
  systems"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  timers: Fix overflow in get_next_timer_interrupt