In preparation for further changes, tidy sdhci_request() a bit.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Tested-by: NBaolin Wang <baolin.wang7@gmail.com>
Link: https://lore.kernel.org/r/20200412090349.1607-5-adrian.hunter@intel.comSigned-off-by: NUlf Hansson <ulf.hansson@linaro.org>

sdhci_finish_data() is defined before it is referenced, so forward
declaration is not necessary.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Tested-by: NBaolin Wang <baolin.wang7@gmail.com>
Link: https://lore.kernel.org/r/20200412090349.1607-4-adrian.hunter@intel.comSigned-off-by: NUlf Hansson <ulf.hansson@linaro.org>

sdhci_send_command() has not been used outside of sdhci.c for many
years. Stop exporting it.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Tested-by: NBaolin Wang <baolin.wang7@gmail.com>
Link: https://lore.kernel.org/r/20200412090349.1607-3-adrian.hunter@intel.comSigned-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Add 2 helper functions to make the use of the auto-CMD23 flag more
readable.
Signed-off-by: NAdrian Hunter <adrian.hunter@intel.com>
Tested-by: NBaolin Wang <baolin.wang7@gmail.com>
Link: https://lore.kernel.org/r/20200412090349.1607-2-adrian.hunter@intel.comSigned-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Use the well defined HIGH_SPEED_BUS_SPEED macro in mmc_sd_switch_hs()
to make code more readable.
Signed-off-by: NJisheng Zhang <Jisheng.Zhang@synaptics.com>
Link: https://lore.kernel.org/r/20200410145643.630b0731@xhacker.debianSigned-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Instead of reimplementing the logic in mmc_regulator_set_vqmmc(), use the
mmc code function directly.

This also allows us to fix a related issue on STM32MP1, when a voltage
switch of 1.8V is done for the eMMC, but the current level is already set
to 1.8V. More precisely, in this scenario the call to the
->post_sig_volt_switch() hangs, indefinitely waiting for the voltage switch
to complete. Fix this problem by checking if mmc_regulator_set_vqmmc()
returned 1 and then skip invoking the callback.
Signed-off-by: NMarek Vasut <marex@denx.de>
Link: https://lore.kernel.org/r/20200416163649.336967-3-marex@denx.de
[Ulf: Updated the commit message]
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Adjust mmc_regulator_set_vqmmc() to return 1 if the voltage switch was
skipped because the regulator voltage was already correct. This allows
drivers to detect such condition and possibly skip various voltage
switching extras.
Signed-off-by: NMarek Vasut <marex@denx.de>
Link: https://lore.kernel.org/r/20200416163649.336967-2-marex@denx.deSigned-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Patch all drivers which use mmc_regulator_set_vqmmc() and prepare them for
the fact that mmc_regulator_set_vqmmc() can return a value > 0, which would
happen if the signal voltage switch did NOT happen, because the voltage was
already set correctly.
Signed-off-by: NMarek Vasut <marex@denx.de>
Link: https://lore.kernel.org/r/20200416163649.336967-1-marex@denx.de
[Ulf: Re-worked/simplified the code a bit]
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Clang warns:

drivers/mmc/host/sdhci-of-arasan.c:784:9: warning: variable 'ret' is
uninitialized when used here [-Wuninitialized]
        return ret;
               ^~~
drivers/mmc/host/sdhci-of-arasan.c:738:9: note: initialize the variable
'ret' to silence this warning
        int ret;
               ^
                = 0
drivers/mmc/host/sdhci-of-arasan.c:860:9: warning: variable 'ret' is
uninitialized when used here [-Wuninitialized]
        return ret;
               ^~~
drivers/mmc/host/sdhci-of-arasan.c:810:9: note: initialize the variable
'ret' to silence this warning
        int ret;
               ^
                = 0
2 warnings generated.

This looks like a copy paste error. Neither function has handling that
needs ret so just remove it and return 0 directly.

Link: https://github.com/ClangBuiltLinux/linux/issues/996Reported-by: Nkernelci.org bot <bot@kernelci.org>
Signed-off-by: NNathan Chancellor <natechancellor@gmail.com>
Reviewed-by: NNick Desaulniers <ndesaulniers@google.com>
Link: https://lore.kernel.org/r/20200416182402.16858-1-natechancellor@gmail.comSigned-off-by: NUlf Hansson <ulf.hansson@linaro.org>

No need to call platform_get_resource twice when we still have the
pointer from before. Also, use '%pa' for a resource_size_t pointer.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: NNiklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Link: https://lore.kernel.org/r/20200408142252.21958-1-wsa+renesas@sang-engineering.comSigned-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Reviewed-by: NGeert Uytterhoeven <geert+renesas@glider.be>

When tuning HS400, if all TAPS are good, we can utilize the SMPCMP
register to select the optimal TAP. For that, we populate a second
bitmap with SMPCMP results and query it in case the regular bitmap is
full (= all good).
Signed-off-by: NMasaharu Hayakawa <masaharu.hayakawa.ry@renesas.com>
Signed-off-by: NTakeshi Saito <takeshi.saito.xv@renesas.com>
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Tested-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/20200408094638.10375-4-wsa+renesas@sang-engineering.comSigned-off-by: NUlf Hansson <ulf.hansson@linaro.org>

The comment and the define about how TAPs are selected were confusing to
me because the good TAP was only valid if it was bigger than a *_MAX_*
value. Rename the define and adapt the comment to what really happens.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/20200408094638.10375-3-wsa+renesas@sang-engineering.comSigned-off-by: NUlf Hansson <ulf.hansson@linaro.org>

To select the best TAP, we need to find the longest stream of set bits
in a bit field. There is now a helper function for bitmaps which
iterates over all region of set bits. Using it makes the code much more
concise and easier to understand. Double so, because we need to handle
two bitmaps in the near future. Remove a superfluous comment while here.
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: NYoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/20200408094638.10375-2-wsa+renesas@sang-engineering.comSigned-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Use FIELD_GET and FIELD_PREP to get access to the register fields. Delete
the shift macros and use GENMASK() for the touched macros.

Note that, this has the side-effect of changing the constants to 64-bit on
64-bit platforms.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: NAdrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/20200408072105.422-2-yamada.masahiro@socionext.comSigned-off-by: NUlf Hansson <ulf.hansson@linaro.org>

In the SDHCI specification, the Capabilities Register (Offset 0x40h)
is the 64-bit width register, but in Linux, it is represented as two
registers, SDHCI_CAPABILITIES and SDHCI_CAPABILITIES_1 so that drivers
can use 32-bit register accessors.

The upper 32-bit field is associated with SDHCI_CAPABILITIES_1.

Move the definition of SDHCI_CAPABILITIES_1 to the correct place.
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: NAdrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/20200408072105.422-1-yamada.masahiro@socionext.comSigned-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Modify code to fix the warnings reported by kernel-doc for better
documentation.
Signed-off-by: NManish Narani <manish.narani@xilinx.com>
Link: https://lore.kernel.org/r/1586195015-128992-7-git-send-email-manish.narani@xilinx.comSigned-off-by: NUlf Hansson <ulf.hansson@linaro.org>

The SDHCI clock operations are platform specific. So it better to define
them separately for particular platform. This will prevent multiple
if..else conditions and will make it easy for user to add their own
clock operations handlers.
Signed-off-by: NManish Narani <manish.narani@xilinx.com>
Link: https://lore.kernel.org/r/1586195015-128992-6-git-send-email-manish.narani@xilinx.comSigned-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Existing driver code has the platform specific structures scattered
throughout the driver code. Rearrange the platform specific data
structures for more modularity and readability. This will help in adding
new static functions with more ease.
Signed-off-by: NManish Narani <manish.narani@xilinx.com>
Link: https://lore.kernel.org/r/1586195015-128992-5-git-send-email-manish.narani@xilinx.comSigned-off-by: NUlf Hansson <ulf.hansson@linaro.org>

There is 'struct sdhci_arasan_data' but also
'struct sdhci_arasan_of_data sdhci_arasan_data'. Rename the latter to
avoid confusion with the name of the struct.
Reported-by: NAdrian Hunter <adrian.hunter@intel.com>
Signed-off-by: NManish Narani <manish.narani@xilinx.com>
Link: https://lore.kernel.org/r/1586195015-128992-4-git-send-email-manish.narani@xilinx.comSigned-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Add support to set tap delays for Xilinx Versal SD controller. The tap
delay registers have moved to SD controller space in Versal. Make the
changes accordingly.
Signed-off-by: NManish Narani <manish.narani@xilinx.com>
Acked-by: NAdrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/1586195015-128992-3-git-send-email-manish.narani@xilinx.comSigned-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Add documentation for 'xlnx,versal-8.9a' SDHCI controller followed by
example.
Signed-off-by: NManish Narani <manish.narani@xilinx.com>
Reviewed-by: NRob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/1586195015-128992-2-git-send-email-manish.narani@xilinx.comSigned-off-by: NUlf Hansson <ulf.hansson@linaro.org>

Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20200409125422.21842-1-ulf.hansson@linaro.org

The in-parameter struct mmc_data *data is never NULL, because the caller
always provides a valid pointer. Hence drop the corresponding redundant
code.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Acked-by: NKrzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20200407143903.22477-1-ulf.hansson@linaro.org

The in-parameter "wait" is always set to 0 by the caller, hence just drop
it and its corresponding code.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Acked-by: NManuel Lauss <manuel.lauss@gmail.com>
Link: https://lore.kernel.org/r/20200406114337.8802-1-ulf.hansson@linaro.org

The MMC_CAP_ERASE and MMC_CAP_CMD23 flags are already being set in the
common sdhci_setup_host(). This makes it redundant to set them for
sdhci-sprd, so let's drop them.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Reviewed-by: NBaolin Wang <baolin.wang7@gmail.com>
Acked-by: NAdrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/20200406113724.8504-1-ulf.hansson@linaro.org

Instead of explicitly checking for SDIO specific requests and then
returning an error code, let's set MMC_CAP2_NO_SDIO to tell the mmc core to
prevent them altogether.
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20200401145531.23247-1-ulf.hansson@linaro.org

Pull EFI fixes from Thomas Gleixner:
 "A set of EFI fixes:

   - Don't return a garbage screen info when EFI framebuffer is not
     available

   - Make the early EFI console work properly with wider fonts instead
     of drawing garbage

   - Prevent a memory buffer leak in allocate_e820()

   - Print the firmware error record properly so it can be decoded by
     users

   - Fix a symbol clash in the host tool build which only happens with
     newer compilers.

   - Add a missing check for the event log version of TPM which caused
     boot failures on several Dell systems due to an attempt to decode
     SHA-1 format with the crypto agile algorithm"

* tag 'efi-urgent-2020-05-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tpm: check event log version before reading final events
  efi: Pull up arch-specific prototype efi_systab_show_arch()
  x86/boot: Mark global variables as static
  efi: cper: Add support for printing Firmware Error Record Reference
  efi/libstub/x86: Avoid EFI map buffer alloc in allocate_e820()
  efi/earlycon: Fix early printk for wider fonts
  efi/libstub: Avoid returning uninitialized data from setup_graphics()

Pull x86 fixes from Thomas Gleixner:
 "Two fixes for x86:

   - Unbreak stack dumps for inactive tasks by interpreting the special
     first frame left by __switch_to_asm() correctly.

     The recent change not to skip the first frame so ORC and frame
     unwinder behave in the same way caused all entries to be
     unreliable, i.e. prepended with '?'.

   - Use cpumask_available() instead of an implicit NULL check of a
     cpumask_var_t in mmio trace to prevent a Clang build warning"

* tag 'x86-urgent-2020-05-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/unwind/orc: Fix unwind_get_return_address_ptr() for inactive tasks
  x86/mmiotrace: Use cpumask_available() for cpumask_var_t variables

Pull scheduler fixes from Thomas Gleixner:
 "A set of fixes for the scheduler:

   - Fix handling of throttled parents in enqueue_task_fair() completely.

     The recent fix overlooked a corner case where the first iteration
     terminates due to an entity already being on the runqueue which
     makes the list management incomplete and later triggers the
     assertion which checks for completeness.

   - Fix a similar problem in unthrottle_cfs_rq().

   - Show the correct uclamp values in procfs which prints the effective
     value twice instead of requested and effective"

* tag 'sched-urgent-2020-05-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/fair: Fix unthrottle_cfs_rq() for leaf_cfs_rq list
  sched/debug: Fix requested task uclamp values shown in procfs
  sched/fair: Fix enqueue_task_fair() warning some more

Pull networking fixes from David Miller:

 1) Fix RCU warnings in ipv6 multicast router code, from Madhuparna
    Bhowmik.

 2) Nexthop attributes aren't being checked properly because of
    mis-initialized iterator, from David Ahern.

 3) Revert iop_idents_reserve() change as it caused performance
    regressions and was just working around what is really a UBSAN bug
    in the compiler. From Yuqi Jin.

 4) Read MAC address properly from ROM in bmac driver (double iteration
    proceeds past end of address array), from Jeremy Kerr.

 5) Add Microsoft Surface device IDs to r8152, from Marc Payne.

 6) Prevent reference to freed SKB in __netif_receive_skb_core(), from
    Boris Sukholitko.

 7) Fix ACK discard behavior in rxrpc, from David Howells.

 8) Preserve flow hash across packet scrubbing in wireguard, from Jason
    A. Donenfeld.

 9) Cap option length properly for SO_BINDTODEVICE in AX25, from Eric
    Dumazet.

10) Fix encryption error checking in kTLS code, from Vadim Fedorenko.

11) Missing BPF prog ref release in flow dissector, from Jakub Sitnicki.

12) dst_cache must be used with BH disabled in tipc, from Eric Dumazet.

13) Fix use after free in mlxsw driver, from Jiri Pirko.

14) Order kTLS key destruction properly in mlx5 driver, from Tariq
    Toukan.

15) Check devm_platform_ioremap_resource() return value properly in
    several drivers, from Tiezhu Yang.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (71 commits)
  net: smsc911x: Fix runtime PM imbalance on error
  net/mlx4_core: fix a memory leak bug.
  net: ethernet: ti: cpsw: fix ASSERT_RTNL() warning during suspend
  net: phy: mscc: fix initialization of the MACsec protocol mode
  net: stmmac: don't attach interface until resume finishes
  net: Fix return value about devm_platform_ioremap_resource()
  net/mlx5: Fix error flow in case of function_setup failure
  net/mlx5e: CT: Correctly get flow rule
  net/mlx5e: Update netdev txq on completions during closure
  net/mlx5: Annotate mutex destroy for root ns
  net/mlx5: Don't maintain a case of del_sw_func being null
  net/mlx5: Fix cleaning unmanaged flow tables
  net/mlx5: Fix memory leak in mlx5_events_init
  net/mlx5e: Fix inner tirs handling
  net/mlx5e: kTLS, Destroy key object after destroying the TIS
  net/mlx5e: Fix allowed tc redirect merged eswitch offload cases
  net/mlx5: Avoid processing commands before cmdif is ready
  net/mlx5: Fix a race when moving command interface to events mode
  net/mlx5: Add command entry handling completion
  rxrpc: Fix a memory leak in rxkad_verify_response()
  ...

Remove runtime PM usage counter decrement when the
increment function has not been called to keep the
counter balanced.
Signed-off-by: NDinghao Liu <dinghao.liu@zju.edu.cn>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Saeed Mahameed says:

====================
mlx5 fixes 2020-05-22

This series introduces some fixes to mlx5 driver.

Please pull and let me know if there is any problem.

For -stable v4.13
   ('net/mlx5: Add command entry handling completion')

For -stable v5.2
   ('net/mlx5: Fix error flow in case of function_setup failure')
   ('net/mlx5: Fix memory leak in mlx5_events_init')

For -stable v5.3
   ('net/mlx5e: Update netdev txq on completions during closure')
   ('net/mlx5e: kTLS, Destroy key object after destroying the TIS')
   ('net/mlx5e: Fix inner tirs handling')

For -stable v5.6
   ('net/mlx5: Fix cleaning unmanaged flow tables')
   ('net/mlx5: Fix a race when moving command interface to events mode')
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In function mlx4_opreq_action(), pointer "mailbox" is not released,
when mlx4_cmd_box() return and error, causing a memory leak bug.
Fix this issue by going to "out" label, mlx4_free_cmd_mailbox() can
free this pointer.

Fixes: fe6f700d ("net/mlx4_core: Respond to operation request by firmware")
Signed-off-by: NQiushi Wu <wu000273@umn.edu>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

vlan_for_each() are required to be called with rtnl_lock taken, otherwise
ASSERT_RTNL() warning will be triggered - which happens now during System
resume from suspend:
  cpsw_suspend()
  |- cpsw_ndo_stop()
    |- __hw_addr_ref_unsync_dev()
      |- cpsw_purge_all_mc()
         |- vlan_for_each()
            |- ASSERT_RTNL();

Hence, fix it by surrounding cpsw_ndo_stop() by rtnl_lock/unlock() calls.

Fixes: 15180eca ("net: ethernet: ti: cpsw: fix vlan mcast")
Signed-off-by: NGrygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

At the very end of the MACsec block initialization in the MSCC PHY
driver, the MACsec "protocol mode" is set. This setting should be set
based on the PHY id within the package, as the bank used to access the
register used depends on this. This was not done correctly, and only the
first bank was used leading to the two upper PHYs being unstable when
using the VSC8584. This patch fixes it.

Fixes: 1bbe0ecc ("net: phy: mscc: macsec initialization")
Signed-off-by: NAntoine Tenart <antoine.tenart@bootlin.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 14b41a29 ("net: stmmac: Delete txtimer in suspend") was the
first attempt to fix a race between mod_timer() and setup_timer()
during stmmac_resume(). However the issue still exists as the commit
only addressed half of the issue.

Same race can still happen as stmmac_resume() re-attaches interface
way too early - even before hardware is fully initialized.  Worse,
doing so allows network traffic to restart and stmmac_tx_timer_arm()
being called in the middle of stmmac_resume(), which re-init tx timers
in stmmac_init_coalesce().  timer_list will be corrupted and system
crashes as a result of race between mod_timer() and setup_timer().

  systemd--1995    2.... 552950018us : stmmac_suspend: 4994
  ksoftirq-9       0..s2 553123133us : stmmac_tx_timer_arm: 2276
  systemd--1995    0.... 553127896us : stmmac_resume: 5101
  systemd--320     7...2 553132752us : stmmac_tx_timer_arm: 2276
  (sd-exec-1999    5...2 553135204us : stmmac_tx_timer_arm: 2276
  ---------------------------------
  pc : run_timer_softirq+0x468/0x5e0
  lr : run_timer_softirq+0x570/0x5e0
  Call trace:
   run_timer_softirq+0x468/0x5e0
   __do_softirq+0x124/0x398
   irq_exit+0xd8/0xe0
   __handle_domain_irq+0x6c/0xc0
   gic_handle_irq+0x60/0xb0
   el1_irq+0xb8/0x180
   arch_cpu_idle+0x38/0x230
   default_idle_call+0x24/0x3c
   do_idle+0x1e0/0x2b8
   cpu_startup_entry+0x28/0x48
   secondary_start_kernel+0x1b4/0x208

Fix this by deferring netif_device_attach() to the end of
stmmac_resume().
Signed-off-by: NLeon Yu <leoyu@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When call function devm_platform_ioremap_resource(), we should use IS_ERR()
to check the return value and return PTR_ERR() if failed.
Signed-off-by: NTiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The srmmu_nocache_init() uses __nocache_fix() macro to add an offset to
page table entry to access srmmu_nocache_pool.

But since sparc32 has only three actual page table levels, pgd, p4d and
pud are essentially the same thing and pgd_offset() and p4d_offset() are
no-ops, the __nocache_fix() should be done only at PUD level.

Remove __nocache_fix() for p4d_offset() and pud_offset() and keep it
only for PUD and lower levels.

Fixes: c2bc26f7 ("sparc32: use PUD rather than PGD to get PMD in srmmu_nocache_init()")
Signed-off-by: NMike Rapoport <rppt@linux.ibm.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Anatoly Pugachev <matorola@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Merge misc fixes from Andrew Morton:
 "11 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  MAINTAINERS: add files related to kdump
  z3fold: fix use-after-free when freeing handles
  sparc32: use PUD rather than PGD to get PMD in srmmu_nocache_init()
  MAINTAINERS: update email address for Naoya Horiguchi
  sh: include linux/time_types.h for sockios
  kasan: disable branch tracing for core runtime
  selftests/vm/write_to_hugetlbfs.c: fix unused variable warning
  selftests/vm/.gitignore: add mremap_dontunmap
  rapidio: fix an error in get_user_pages_fast() error handling
  x86: bitops: fix build regression
  device-dax: don't leak kernel memory to user space after unloading kmem