At least the tcm_qla2xxx fabric driver calls into transport_deregister_session()
while holding an IRQ-disabled spinlock, so the inner locking needs to
use spin_lock_irqsave() instead of spin_lock_bh().

This fixes warnings seen with tcm_qla2xxx like:

    WARNING: at kernel/softirq.c:159 local_bh_enable_ip+0x98/0xb0()
    Call Trace:
     [<ffffffff8104e65f>] warn_slowpath_common+0x7f/0xc0
     [<ffffffff8104e6ba>] warn_slowpath_null+0x1a/0x20
     [<ffffffff81055368>] local_bh_enable_ip+0x98/0xb0
     [<ffffffff814d5284>] _raw_spin_unlock_bh+0x14/0x20
     [<ffffffffa027b7f6>] transport_deregister_session+0x96/0x180 [target_core_mod]
     [<ffffffffa00f7731>] tcm_qla2xxx_free_session+0xd1/0x170 [tcm_qla2xxx]
     [<ffffffffa01b9173>] qla_tgt_sess_put+0xc3/0x140 [qla2xxx]
     [<ffffffffa01bf40f>] qla_tgt_stop_phase1+0x8f/0x2c0 [qla2xxx]
     [<ffffffffa00f735e>] tcm_qla2xxx_tpg_store_enable+0x6e/0xd0 [tcm_qla2xxx]
     [<ffffffffa026ca29>] target_fabric_tpg_attr_store+0x39/0x40 [target_core_mod]
     [<ffffffffa00a575d>] configfs_write_file+0xbd/0x120 [configfs]
     [<ffffffff811464a6>] vfs_write+0xc6/0x180
     [<ffffffff811467c1>] sys_write+0x51/0x90
     [<ffffffff814dd382>] system_call_fastpath+0x16/0x1b
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

There's no need for the #ifdef protection when building into the kernel,
and in fact we need the module_init() for the initialization function to
be called.
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Make a log message more useful by printing both the page and subpage
that an initiator is requesting.
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch fixes two bugs in allocation failure handling in
iscsit_allocate_se_cmd_for_tmr():

This first reported by DanC is a free-after call to transport_free_se_cmd(), this
patch drops the transport_free_se_cmd() call all together, as iscsit_release_cmd()
will release existing allocations as expected.

The second is a bug where iscsi_cmd_t was being leaked on a cmd->tmr_req allocation
failure, so make this jump to iscsit_release_cmd() as well.
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

The iSCSI target configfs code to print out an initiator's IPv6 address
is not fully implemented. This patch uses snprintf() with the "%pI6c"
format string to format the IPv6 address for display purposes.
Signed-off-by: Chris Boot <bootc@bootc.net>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch fixes two bugs associated with transport_do_task_sg_chain()
operation where transport_allocate_data_tasks() was incorrectly setting
task_padded_sg for all tasks, and causing bogus task->task_sg_nents
assignments + OOPsen with fabrics depending upon this code.  The first bit
here adds a task_sg_nents_padded check in transport_allocate_data_tasks()
to include an extra SGL vector when necessary for tasks that expect to
be linked using sg_chain().

The second change involves making transport_do_task_sg_chain() properly
account for the extra SGL vector when task->task_padded_sg is set for
the non trailing ->task_sg or single ->task_sg allocations.  Note this
patch also removes the BUG_ON(!task->task_padded_sg) check within
transport_do_task_sg_chain() as we expect this to happen normally
with the updated logic in transport_allocate_data_tasks(), along with
being bogus for CONTROL_SG_IO_CDB type payloads.

So far this bugfix has been tested with tcm_qla2xxx and iblock backends
in (task_count > 1)( and (task_count == 1) operation.
Reported-by: Kiran Patil <kiran.patil@intel.com>
Cc: Kiran Patil <kiran.patil@intel.com>
Cc: Andy Grover <agrover@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch addresses recent breakage with multiple se_task (task_count > 1)
operation following backend dev->se_sub_dev->se_dev_attrib.max_sectors in new
transport_allocate_data_tasks() code.  The initial bug here was a bogus
task->task_sg_nents assignment in transport_allocate_data_tasks() based on
the passed parameter, which now uses DIV_ROUND_UP(task_size, PAGE_SIZE) to
determine the proper number of per task SGL entries for the (task_count > 1)
case.

This also means we now need to enforce a PAGE_SIZE aligned max_sector count
value for this to work as expected without bringing back the pre v3.1
transport_map_mem_to_sg() logic to handle SGL offsets across multiple tasks.
So this patch adds se_dev_align_max_sectors() to round down max_sectors as
necessary to ensure this alignment via se_dev_set_default_attribs() and
se_dev_align_max_sectors() and keeps it simple for (task_count > 1)
operation.

So far this bugfix has been tested with (task_count > 1) operation
using iscsi-target and iblock backends.
Reported-by: Chris Boot <bootc@bootc.net>
Cc: Kiran Patil <kiran.patil@intel.com>
Cc: Andy Grover <agrover@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch adds the missing transport_cmd_get_valid_sectors() check for
SCF_SCSI_DATA_SG_IO_CDB type payloads to ensure that a received LBA + range
does not exeed past the end of associated backend struct se_device.

This patch also fixes a bug in the failure path of transport_new_cmd_obj()
where this check can fail, so change to use a signed 'rc' and return '-EINVAL'
to signal proper transport_generic_request_failure() handling.
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch fixes a SYNCHRONIZE_CACHE CDB handling bug with IBLOCK/FILEIO
backends where transport_cmd_get_valid_sectors() was incorrectly rejecting
a zero LBA + range CDB from being processed, and returning CHECK_CONDITION.

This includes changing transport_cmd_get_valid_sectors() to return '0' on
success and '-EINVAL' on failure (this makes more sense than sectors),
and to only check transport_cmd_get_valid_sectors() when a non zero LBA +
range SYNCHRONIZE_CACHE operation has been receieved for the non passthrough
case.
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch removes a duplicate set of transport_complete_task() calls in
target_emulate_unmap() and target_emulate_write_same() as the completion
call is already done within transport_emulate_control_cdb()

This patch also adds a check in transport_emulate_control_cdb() for the
existing SCF_EMULATE_CDB_ASYNC flag currently used by SYNCHRONIZE_CACHE
in order to handle IMMEDIATE processing.
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

For all flavours of WRITE_SAME, we only expect to handle a single block
of data-out buffer payload, regardless of the number of logical blocks
presented in the CDB.  This patch changes all flavours of WRITE_SAME in
transport_generic_cmd_sequencer() to pass '1' into transport_get_size()
instead of the extracted 'sectors' to properly handle the default usage
of sg_write_same without the --xferlen parameter.
Reported-by: Eric Seppanen <eric@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@risingtidesystems.com>

This patch adds initial WRITE_SAME (10) w/ UNMAP=1 support following updates in
sbcr26 to allow UNMAP=1 for the non 16 + 32 byte CDB case.  It also refactors
current pSCSI passthrough passthrough checks into target_check_write_same_discard()
ahead of UNMAP=0 w/ write payload support into target_core_iblock.c.

This includes the support for handling WRITE_SAME in transport_emulate_control_cdb(),
and converts target_emulate_write_same to accept num_blocks directly for
WRITE_SAME, WRITE_SAME_16 and WRITE_SAME_32.
Reported-by: Eric Seppanen <eric@purestorage.com>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@risingtidesystems.com>

This patch fixes a bug for fabrics using tfo->new_cmd_map() that
are expect transport_generic_request_failure() to be calling
transport_send_check_condition_and_sense() for both READ and WRITE,
instead of only for READ exceptions.

This was originally observed with a failed WRITE_SAME_16 w/ unmap=0
using tcm_loop.
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch fixes a forever loop bug in iscsit_attach_ooo_cmdsn()
while walking sess->sess_ooo_cmdsn_list when the received
CmdSN is less than the tail of the list.
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

We returned on the line before already.
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Use BUG_ON(x) rather than if(x) BUG();

The semantic patch that fixes this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ identifier x; @@
-if (x) BUG();
+BUG_ON(x);

@@ identifier x; @@
-if (!x) BUG();
+BUG_ON(!x);
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

We leak memory if the allocations for 'new_param->name' or
'new_param->value' fail in iscsi_target_parameters.c::iscsi_copy_param_list()

We also do a lot of variable assignments that are completely pointless
if the allocations fail.

So, let's move the allocations before the assignments and also make
sure that we free whatever was allocated to one if the allocation fail.

There's also some small CodingStyle fixups in there (curly braces on
both branches of if statement, only one variable per line) since I was
in the area anyway. And finally, error messages in the function are
put on a single line for easy grep'abillity.
Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Use ERR_CAST inlined function instead of ERR_PTR(PTR_ERR(...))

The semantic patch that makes this output is available
in scripts/coccinelle/api/err_cast.cocci.

More information about semantic patching is available at
http://coccinelle.lip6.fr/Signed-off-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch changes target_emulate_inquiry_std() to set the 'not connected'
(0x35) bit in standard INQUIRY response data when we are processing a
request to a virtual LUN=0 mapping from struct se_device *g_lun0_dev that
have been setup for us in transport_lookup_cmd_lun().

This addresses an issue where qla2xxx FC clients need to be able
to create demo-mode I_T FC Nexuses by default, but should not be
exposing the default set of TPG LUNs to all FC clients.  This includes
adding an new optional target_core_fabric_ops->tpg_check_demo_mode_login_only()
caller to allow demo_mode nexuses to skip the old default of bulding
a demo-mode MappedLUNs list via core_tpg_add_node_to_devs().

(roland: Add missing tpg_check_demo_mode_login_only check in core_dev_add_lun)
Reported-by: Roland Dreier <roland@purestorage.com>
Cc: Andrew Vasquez <andrew.vasquez@qlogic.com>
Signed-off-by: Nicholas Bellinger <nab@risingtidesystems.com>

This patch changes transport_send_check_condition_and_sense() for
TCM_NON_EXISTENT_LUN emulation to use 0x25 (LOGICAL UNIT NOT SUPPORTED)
instead of the original 0x20 (INVALID COMMAND OPERATION CODE).  This is
helpful to distinguish between TCM_UNSUPPORTED_SCSI_OPCODE ASC=0x20
exceptions.
Signed-off-by: Nicholas A. Bellinger <nab@risingtidesystems.com>

Commit db64fe02 ("mm: rewrite vmap layer") introduced code that does
address calculations under the assumption that VMAP_BLOCK_SIZE is a
power of two.  However, this might not be true if CONFIG_NR_CPUS is not
set to a power of two.

Wrong vmap_block index/offset values could lead to memory corruption.
However, this has never been observed in practice (or never been
diagnosed correctly); what caught this was the BUG_ON in vb_alloc() that
checks for inconsistent vmap_block indices.

To fix this, ensure that VMAP_BLOCK_SIZE always is a power of two.

BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=31572Reported-by: Pavel Kysilka <goldenfish@linuxsoft.cz>
Reported-by: Matias A. Fonzo <selk@dragora.org>
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Krzysztof Helt <krzysztof.h1@poczta.fm>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: 2.6.28+ <stable@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc:
  mmc: remove unused "ddr" parameter in struct mmc_ios
  mmc: dw_mmc: Fix DDR mode support.
  mmc: core: use defined R1_STATE_PRG macro for card status
  mmc: sdhci: use f_max instead of host->clock for timeouts
  mmc: sdhci: move timeout_clk calculation farther down
  mmc: sdhci: check host->clock before using it as a denominator
  mmc: Revert "mmc: sdhci: Fix SDHCI_QUIRK_TIMEOUT_USES_SDCLK"
  mmc: tmio: eliminate unused variable 'mmc' warning
  mmc: esdhc-imx: fix card interrupt loss on freescale eSDHC
  mmc: sdhci-s3c: Fix build for header change
  mmc: dw_mmc: Fix mask in IDMAC_SET_BUFFER1_SIZE macro
  mmc: cb710: fix possible pci_dev leak in cb710_pci_configure()
  mmc: core: Detect eMMC v4.5 ext_csd entries
  mmc: mmc_test: avoid stalled file in debugfs
  mmc: sdhci-s3c: add BROKEN_ADMA_ZEROLEN_DESC quirk
  mmc: sdhci: pxav3: controller needs 32 bit ADMA addressing
  mmc: sdhci: fix retuning timer wrongly deleted in sdhci_tasklet_finish

* 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/staging:
  hwmon: (ibmaem) add missing kfree
  hwmon: (pmbus/lm25066) Ignore byte writes to non-zero pages
  hwmon: (pmbus) Virtualize pmbus_write_byte

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6:
  ASoC: Fix compile warning in wm8750.c
  ASoC: omap: Update e-mail address of Jarkko Nikula
  ASoC: SAMSUNG: Add I2S0 internal dma driver
  ASoC: Terminate WM8750 SPI device ID table
  ASoC: Add missing break in WM8994 probe
  ALSA: snd-usb-caiaq: Correct offset fields of outbound iso_frame_desc
  ALSA: azt3328 - adjust error handling code to include debugging code
  ALSA: hda - Add CONFIG_SND_HDA_POWER_SAVE to stac_vrefout_set()
  ALSA: usb-audio - Add quirk for BOSS Micro BR-80
  ASoC: Fix typo in wm8750 spi_ids
  ASoC: Fix warning in Speyside WM8962
  ASoC: Fix SPI driver binding for WM8987
  ASoC: Fix binding of WM8750 on Jive
  ASoC: WM8903: Free IRQ on device removal
  ASoC: Tegra: wm8903 machine driver: Allow re-insertion of module
  ASoC: Tegra: tegra_pcm_deallocate_dma_buffer: Don't OOPS

Remove the name of Sergey Kostyliov as maintainer of befs.
In the MAINTAINERS file, befs is orphaned.
Signed-off-by: Marcos Souza <marcos.mage@gmail.com>
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Change resource URL to new git tree -
(http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git).
Signed-off-by: Ralf Thielow <ralf.thielow@googlemail.com>
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add a documentation file describing the usage of Ramoops
Signed-off-by: Sergiu Iordache <sergiu@chromium.org>
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add better Thunderbird information.
Add Thunderbird Registry instructions to:
  Enable UTF8 & Preformat mode
  Disable HTML mode
Signed-off-by: Paul McQuade <paulmcquad@gmail.com>
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

General cleanups to kernel-parameters.txt:
 - add missing $ARCH that are being used/referenced
 - alphabetize the parameter restrictions list
 - spell "IA-64" as listed in arch/ia64/Kconfig instead of "IA64"
 - remove trailing whitespace
 - use hyphen in 32-bit etc.
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Usually kernel parameters are documented in kernel-parameters.txt
but user_debug is only documented in the Kconfig. Document the
option and point to the Kconfig help text for more info.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Dropping LSD (Linux Source Driver) since it hasn't been available
for a long time.
Signed-off-by: Luis de Bethencourt <luis@debethencourt.com>
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fixed a spelling error.
Signed-off-by: Zac Storer <zac.3.14159@gmail.com>
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

"mmc: dw_mmc: Fix DDR mode support" removed the last user.
Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

Host driver can't get a hint of DDR mode through ios->ddr flag anymore.
ios->timing is currently used to inform DDR mode as a substitute.
And capability of MMC_CAP_MMC_HIGHSPEED is added for DDR support.
Signed-off-by: Seungwon Jeon <tgih.jun@samsung.com>
Acked-by: Will Newton <will.newton@imgtec.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

When timeout_clk is calculated the host->clock could be zero.
So, instead of host->clock the calculation now uses mmc->f_max.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

This moves the calculation below the assignment of mmc->f_max, which
we need for calculating timeout_clk in the next patch in this series.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

Sometimes host->clock could be zero which is a legal situation. This
patch checks host->clock before usage as a denominator when timeout is
calculated. A similar patch is applied for mmc core (see commit e9b86841,
"mmc: fix division by zero in MMC core").

Without this patch, the execution of the sdhci_calc_timeout could end up
with a backtrace:

<0>[    4.014319] divide error: 0000 [#1] PREEMPT SMP
<4>[    4.014352] Modules linked in: g_ether
<4>[    4.014376]
<4>[    4.014393] Pid: 33, comm: kworker/u:2 Not tainted 3.0.0+ #646
<4>[    4.014421] EIP: 0060:[<c12fa38e>] EFLAGS: 00010046 CPU: 1
<4>[    4.014449] EIP is at sdhci_calc_timeout+0x2e/0x100
<4>[    4.014468] EAX: 00000000 EBX: f5930fc8 ECX: 00000000 EDX: 00000000
<4>[    4.014488] ESI: f5291de8 EDI: f5291db8 EBP: f5291c6c ESP: f5291c50
<4>[    4.014508]  DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
<0>[    4.014529] Process kworker/u:2 (pid: 33, ti=f5290000 task=f53065a0 task.ti=f5290000)
<0>[    4.014546] Stack:
<4>[    4.014557]  00000082 c1054fdd f5291c78 04000000 f5930fc8 f5291de8 f5291db8 f5291cac
<4>[    4.014611]  c12fab7c c107a98b f5291c88 c13b6d3f f593109c f5882000 f5291cac c1054fdd
<4>[    4.014663]  00000000 00000000 f5882000 00000082 f5930fc8 f5291db8 0000000a f5291ccc
<0>[    4.014716] Call Trace:
<4>[    4.014743]  [<c1054fdd>] ? mod_timer+0x11d/0x380
<4>[    4.014770]  [<c12fab7c>] sdhci_prepare_data+0x2c/0x3a0
<4>[    4.014798]  [<c107a98b>] ? trace_hardirqs_off+0xb/0x10
<4>[    4.014827]  [<c13b6d3f>] ? _raw_spin_unlock_irqrestore+0x2f/0x60
<4>[    4.014854]  [<c1054fdd>] ? mod_timer+0x11d/0x380
<4>[    4.014880]  [<c12fc7db>] sdhci_send_command+0xdb/0x210
<4>[    4.014906]  [<c12fd5f3>] sdhci_request+0xc3/0x150
<4>[    4.014932]  [<c12ec56a>] mmc_start_request+0xda/0x200
<4>[    4.014960]  [<c120d7c2>] ? __raw_spin_lock_init+0x32/0x60
<4>[    4.014989]  [<c1066a85>] ? __init_waitqueue_head+0x35/0x50
<4>[    4.015015]  [<c12ec70b>] mmc_wait_for_req+0x7b/0x90
<4>[    4.015045]  [<c12f0c67>] mmc_send_cxd_data+0xf7/0x130
<4>[    4.015076]  [<c12ecbc0>] ? mmc_erase+0x140/0x140
<4>[    4.015102]  [<c12f139d>] mmc_send_ext_csd+0x1d/0x20
<4>[    4.015125]  [<c12efef0>] mmc_get_ext_csd+0x70/0x140
<4>[    4.015151]  [<c12effe8>] mmc_compare_ext_csds+0x28/0x190
<4>[    4.015176]  [<c12f039f>] mmc_init_card+0x24f/0x650
<4>[    4.015201]  [<c13b6d5d>] ? _raw_spin_unlock_irqrestore+0x4d/0x60
<4>[    4.015226]  [<c107fd9c>] ? trace_hardirqs_on_caller+0x11c/0x160
<4>[    4.015255]  [<c12f09a4>] mmc_attach_mmc+0xa4/0x190
<4>[    4.015282]  [<c12ee3f0>] mmc_rescan+0x210/0x240
<4>[    4.015311]  [<c105f9b6>] process_one_work+0x176/0x550
<4>[    4.015336]  [<c105f93a>] ? process_one_work+0xfa/0x550
<4>[    4.015360]  [<c12ee1e0>] ? mmc_init_erase+0x140/0x140
<4>[    4.015385]  [<c1061c2a>] worker_thread+0x12a/0x2c0
<4>[    4.015410]  [<c1061b00>] ? manage_workers.clone.18+0x100/0x100
<4>[    4.015437]  [<c1066244>] kthread+0x74/0x80
<4>[    4.015463]  [<c10661d0>] ? __init_kthread_worker+0x60/0x60
<4>[    4.015490]  [<c13b7dfa>] kernel_thread_helper+0x6/0xd
<0>[    4.015507] Code: 57 89 d7 56 53 89 c3 83 ec 10 8b 40 04 8b 72 28 f6 c4 10 89 45 f0 0f 85 91 00 00 00 85 f6 0f 84 c1 00 00 00 8b 4e 04 31 d2 89 c8 <f7> 73 58 ba d3 4d 62 10 89 c1 8b 06 f7 e2 c1 ea 06 01 d1 f7 45
<0>[    4.015829] EIP: [<c12fa38e>] sdhci_calc_timeout+0x2e/0x100 SS:ESP 0068:f5291c50
Reported-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

This reverts commit 4b01681c, which introduced a new potential
divide by zero in the process of fixing one.  The subsequent commits
attempt to fix the issue properly.
Signed-off-by: Chris Ball <cjb@laptop.org>