The following members of struct transaction_s aka transaction_t
were turned into lock-free variables in the past:
- t_updates
- t_outstanding_credits
- t_handle_count
However, the documentation has not been updated yet.
This commit replaced the annotated lock by [none].
Found by LockDoc (Alexander Lochmann, Horst Schirmeier and Olaf Spinczyk)
Signed-off-by: Alexander Lochmann <alexander.lochmann@tu-dortmund.de>
Signed-off-by: Horst Schirmeier <horst.schirmeier@tu-dortmund.de>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
We can hold j_state_lock for writing at the beginning of
jbd2_journal_commit_transaction() for a rather long time (reportedly for
30 ms) due cleaning revoke bits of all revoked buffers under it. The
handling of revoke tables as well as cleaning of t_reserved_list, and
checkpoint lists does not need j_state_lock for anything. It is only
needed to prevent new handles from joining the transaction. Generally
T_LOCKED transaction state prevents new handles from joining the
transaction - except for reserved handles which have to allowed to join
while we wait for other handles to complete.
To prevent reserved handles from joining the transaction while cleaning
up lists, add new transaction state T_SWITCH and watch for it when
starting reserved handles. With this we can just drop the lock for
operations that don't need it.
Reported-and-tested-by: Adrian Hunter <adrian.hunter@intel.com>
Suggested-by: "Theodore Y. Ts'o" <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Instead of running with interrupts disabled, use a semaphore. This should
make it easier for backends that may need to sleep (e.g. EFI) when
performing a write:
|BUG: sleeping function called from invalid context at kernel/sched/completion.c:99
|in_atomic(): 1, irqs_disabled(): 1, pid: 2236, name: sig-xstate-bum
|Preemption disabled at:
|[<ffffffff99d60512>] pstore_dump+0x72/0x330
|CPU: 26 PID: 2236 Comm: sig-xstate-bum Tainted: G D 4.20.0-rc3 #45
|Call Trace:
| dump_stack+0x4f/0x6a
| ___might_sleep.cold.91+0xd3/0xe4
| __might_sleep+0x50/0x90
| wait_for_completion+0x32/0x130
| virt_efi_query_variable_info+0x14e/0x160
| efi_query_variable_store+0x51/0x1a0
| efivar_entry_set_safe+0xa3/0x1b0
| efi_pstore_write+0x109/0x140
| pstore_dump+0x11c/0x330
| kmsg_dump+0xa4/0xd0
| oops_exit+0x22/0x30
...
Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Fixes: 21b3ddd39f ("efi: Don't use spinlocks for efi vars")
Signed-off-by: Kees Cook <keescook@chromium.org>
In later patches we will need to map types to names, so create a
constant table for that which can also be used in different parts of
old and new code. This saves the type in the PRZ which will be useful
in later patches.
Instead of having an explicit PSTORE_TYPE_UNKNOWN, just use ..._MAX.
This includes removing the now redundant filename templates which can use
a single format string. Also, there's no reason to limit the "is it still
compressed?" test to only PSTORE_TYPE_DMESG when building the pstorefs
filename. Records are zero-initialized, so a backend would need to have
explicitly set compressed=1.
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Co-developed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
This improves and updates some comments:
- dump handler comment out of sync from calling convention
- fix kern-doc typo
and improves status output:
- reminder that only kernel crash dumps are compressed
- do not be silent about ECC infrastructure failures
Signed-off-by: Kees Cook <keescook@chromium.org>
When initialing a prz, if invalid data is found (no PERSISTENT_RAM_SIG),
the function call path looks like this:
ramoops_init_prz ->
persistent_ram_new -> persistent_ram_post_init -> persistent_ram_zap
persistent_ram_zap
As we can see, persistent_ram_zap() is called twice.
We can avoid this by adding an option to persistent_ram_new(), and
only call persistent_ram_zap() when it is needed.
Signed-off-by: Peng Wang <wangpeng15@xiaomi.com>
[kees: minor tweak to exit path and commit log]
Signed-off-by: Kees Cook <keescook@chromium.org>
We need to ignore bits in the cleared mask when iterating over all set
bits.
Fixes: ea86ea2cdc ("sbitmap: ammortize cost of clearing bits")
Reported-by: Jens Axboe@kernel.dk>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
With MSG_ZEROCOPY, each skb holds a reference to a struct ubuf_info.
Release of its last reference triggers a completion notification.
The TCP stack in tcp_sendmsg_locked holds an extra ref independent of
the skbs, because it can build, send and free skbs within its loop,
possibly reaching refcount zero and freeing the ubuf_info too soon.
The UDP stack currently also takes this extra ref, but does not need
it as all skbs are sent after return from __ip(6)_append_data.
Avoid the extra refcount_inc and refcount_dec_and_test, and generally
the sock_zerocopy_put in the common path, by passing the initial
reference to the first skb.
This approach is taken instead of initializing the refcount to 0, as
that would generate error "refcount_t: increment on 0" on the
next skb_zcopy_set.
Changes
v3 -> v4
- Move skb_zcopy_set below the only kfree_skb that might cause
a premature uarg destroy before skb_zerocopy_put_abort
- Move the entire skb_shinfo assignment block, to keep that
cacheline access in one place
Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Extend zerocopy to udp sockets. Allow setting sockopt SO_ZEROCOPY and
interpret flag MSG_ZEROCOPY.
This patch was previously part of the zerocopy RFC patchsets. Zerocopy
is not effective at small MTU. With segmentation offload building
larger datagrams, the benefit of page flipping outweights the cost of
generating a completion notification.
tools/testing/selftests/net/msg_zerocopy.sh after applying follow-on
test patch and making skb_orphan_frags_rx same as skb_orphan_frags:
ipv4 udp -t 1
tx=191312 (11938 MB) txc=0 zc=n
rx=191312 (11938 MB)
ipv4 udp -z -t 1
tx=304507 (19002 MB) txc=304507 zc=y
rx=304507 (19002 MB)
ok
ipv6 udp -t 1
tx=174485 (10888 MB) txc=0 zc=n
rx=174485 (10888 MB)
ipv6 udp -z -t 1
tx=294801 (18396 MB) txc=294801 zc=y
rx=294801 (18396 MB)
ok
Changes
v1 -> v2
- Fixup reverse christmas tree violation
v2 -> v3
- Split refcount avoidance optimization into separate patch
- Fix refcount leak on error in fragmented case
(thanks to Paolo Abeni for pointing this one out!)
- Fix refcount inc on zero
- Test sock_flag SOCK_ZEROCOPY directly in __ip_append_data.
This is needed since commit 5cf4a8532c ("tcp: really ignore
MSG_ZEROCOPY if no SO_ZEROCOPY") did the same for tcp.
Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In sctp_hash_transport/sctp_epaddr_lookup_transport, it dereferences
a transport's asoc under rcu_read_lock while asoc is freed not after
a grace period, which leads to a use-after-free panic.
This patch fixes it by calling kfree_rcu to make asoc be freed after
a grace period.
Note that only the asoc's memory is delayed to free in the patch, it
won't cause sk to linger longer.
Thanks Neil and Marcelo to make this clear.
Fixes: 7fda702f93 ("sctp: use new rhlist interface on sctp transport rhashtable")
Fixes: cd2b708750 ("sctp: check duplicate node before inserting a new transport")
Reported-by: syzbot+0b05d8aa7cb185107483@syzkaller.appspotmail.com
Reported-by: syzbot+aad231d51b1923158444@syzkaller.appspotmail.com
Suggested-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Kalle Valo says:
====================
wireless-drivers-next patches for 4.21
First set of patches for 4.21. Most notable here is support for
Quantenna's QSR1000/QSR2000 chipsets and more flexible ways to provide
nvram files for brcmfmac.
Major changes:
brcmfmac
* add support for first trying to get a board specific nvram file
* add support for getting nvram contents from EFI variables
qtnfmac
* use single PCIe driver for all platforms and rename
Kconfig option CONFIG_QTNFMAC_PEARL_PCIE to CONFIG_QTNFMAC_PCIE
* add support for QSR1000/QSR2000 (Topaz) family of chipsets
ath10k
* add support for WCN3990 firmware crash recovery
* add firmware memory dump support for QCA4019
wil6210
* add firmware error recovery while in AP mode
ath9k
* remove experimental notice from dynack feature
iwlwifi
* PCI IDs for some new 9000-series cards
* improve antenna usage on connection problems
* new firmware debugging infrastructure
* some more work on 802.11ax
* improve support for multiple RF modules with 22000 devices
cordic
* move cordic macros and defines to a public header file
* convert brcmsmac and b43 to fully use cordic library
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
We've switched all users to nvmem_get_mac_address(). Remove the now
dead code.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
We already have of_get_nvmem_mac_address() but some non-DT systems want
to read the MAC address from NVMEM too. Implement a generalized routine
that takes struct device as argument.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some users of rhashtables might need to move an object from one table
to another - this appears to be the reason for the incomplete usage
of NULLS markers.
To support these, we store a unique NULLS_MARKER at the end of
each chain, and when a search fails to find a match, we check
if the NULLS marker found was the expected one. If not, the search
may not have examined all objects in the target bucket, so it is
repeated.
The unique NULLS_MARKER is derived from the address of the
head of the chain. As this cannot be derived at load-time the
static rhnull in rht_bucket_nested() needs to be initialised
at run time.
Any caller of a lookup function must still be prepared for the
possibility that the object returned is in a different table - it
might have been there for some time.
Note that this does NOT provide support for other uses of
NULLS_MARKERs such as allocating with SLAB_TYPESAFE_BY_RCU or changing
the key of an object and re-inserting it in the same table.
These could only be done safely if new objects were inserted
at the *start* of a hash chain, and that is not currently the case.
Signed-off-by: NeilBrown <neilb@suse.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Existing functions to retreive the l3mdev of a device did not walk the
master chain to find the upper master. This patch adds a function to
find the l3mdev, even indirect through e.g. a bridge:
+----------+
| |
| vrf-blue |
| |
+----+-----+
|
|
+----+-----+
| |
| br-blue |
| |
+----+-----+
|
|
+----+-----+
| |
| eth0 |
| |
+----------+
This will properly resolve the l3mdev of eth0 to vrf-blue.
Signed-off-by: Alexis Bauvin <abauvin@scaleway.com>
Reviewed-by: Amine Kherbouche <akherbouche@scaleway.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Tested-by: Amine Kherbouche <akherbouche@scaleway.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
UDP tunnel sockets are always opened unbound to a specific device. This
patch allow the socket to be bound on a custom device, which
incidentally makes UDP tunnels VRF-aware if binding to an l3mdev.
Signed-off-by: Alexis Bauvin <abauvin@scaleway.com>
Reviewed-by: Amine Kherbouche <akherbouche@scaleway.com>
Tested-by: Amine Kherbouche <akherbouche@scaleway.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Many drivers load the device's firmware image during the initialization
flow either from the flash or from the disk. Currently this option is not
controlled by the user and the driver decides from where to load the
firmware image.
'fw_load_policy' gives the ability to control this option which allows the
user to choose between different loading policies supported by the driver.
This parameter can be useful while testing and/or debugging the device. For
example, testing a firmware bug fix.
Signed-off-by: Shalom Toledo <shalomt@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As the pxa architecture and all its related drivers do not rely anymore
on the filter function, thanks to the slave map conversion, make
pxad_filter_fn() static, and remove it from the global namespace.
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Acked-by: Vinod Koul <vkoul@kernel.org>
Qualcomm ARM Based Driver Updates for v4.21
* Fix llcc license, includes, and error checks
* Remove use of memcpy in cmd-db and fix API breakage
* Add QCS404 compatible to SMD-RPM
* Minor fixes for QMI
* Add irq clear handling in QCOM Geni SE during init
* tag 'qcom-drivers-for-4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/agross/linux:
drm: msm: Check cmd_db_read_aux_data() for failure
soc: qcom: smd-rpm: Add QCS404 compatible
soc: qcom: llcc-slice: Remove duplicated include from llcc-slice.c
soc: qcom: cmd-db: Stop memcpy()ing in cmd_db_read_aux_data()
soc: qcom: cmd-db: Remove memcpy()ing from cmd_db_get_header()
soc: qcom: Drop help text for QCOM_QMI_HELPERS
soc: qcom: qmi_interface: Limit txn ids to U16_MAX
soc: qcom: llcc-slice: Add error checks for API functions
soc: qcom/llcc: add MODULE_LICENSE tag
soc: qcom: Add irq clear handling during SE init
Signed-off-by: Olof Johansson <olof@lixom.net>
This pull request contains Broadcom ARM/ARM64/MIPS SoCs drivers changes
for 4.21, please pull the following changes:
- James fixes the firmware interface after a commit changed the use of
VLA and broke large transfers
- Stefan adds a timeout check for Raspberry Pi firmware transactions and
updates a bunch of SoC/firmware files to use SPDX tags
- Wolfram switches the GISB bus arbiter to use dev_get_drvdata()
- Yangtao provides a fix for a reference leak due to a call to
of_find_node_by_path()
- Florian fixes the CPU re-entry point out of S3 suspend with kernels
built in Thumb2 mode
* tag 'arm-soc/for-4.21/drivers' of https://github.com/Broadcom/stblinux:
soc: bcm: brcmstb: Don't leak device tree node reference
firmware: raspberrypi: Switch to SPDX identifier
firmware: raspberrypi: Fix firmware calls with large buffers
soc: bcm: Switch raspberrypi-power to SPDX identifier
firmware: raspberrypi: Define timeout for transactions
bus: brcmstb_gisb: simplify getting .driver_data
soc: bcm: brcmstb: Fix re-entry point with a THUMB2_KERNEL
Signed-off-by: Olof Johansson <olof@lixom.net>
The missing indentation on the "Return" sections for bpf_map_pop_elem()
and bpf_map_peek_elem() helpers break RST and man pages generation. This
patch fixes them, and moves the description of those two helpers towards
the end of the list (even though they are somehow related to the three
first helpers for maps, the man page explicitly states that the helpers
are sorted in chronological order).
While at it, bring other minor formatting edits for eBPF helpers
documentation: mostly blank lines removal, RST formatting, or other
small nits for consistency.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
The pkt_len field in qdisc_skb_cb stores the skb length as it will
appear on the wire after segmentation. For byte accounting, this value
is more accurate than skb->len. It is computed on entry to the TC
layer, so only valid there.
Allow read access to this field from BPF tc classifier and action
programs. The implementation is analogous to tc_classid, aside from
restricting to read access.
To distinguish it from skb->len and self-describe export as wire_len.
Changes v1->v2
- Rename pkt_len to wire_len
Signed-off-by: Petar Penkov <ppenkov@google.com>
Signed-off-by: Vlad Dumitrescu <vladum@google.com>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
When vb2_buffer_done is called the buffer is unbound from the
request and put. The media_request_object_put also 'put's the
request reference. If the application has already closed the
request fd, then that means that the request reference at that
point goes to 0 and the whole request is released.
This means that the control handler associated with the request is
also freed and that causes this kernel oops:
[174705.995401] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:908
[174705.995411] in_atomic(): 1, irqs_disabled(): 1, pid: 28071, name: vivid-000-vid-o
[174705.995416] 2 locks held by vivid-000-vid-o/28071:
[174705.995420] #0: 000000001ea3a232 (&dev->mutex#3){....}, at: vivid_thread_vid_out+0x3f5/0x550 [vivid]
[174705.995447] #1: 00000000e30a0d1e (&(&q->done_lock)->rlock){....}, at: vb2_buffer_done+0x92/0x1d0 [videobuf2_common]
[174705.995460] Preemption disabled at:
[174705.995461] [<0000000000000000>] (null)
[174705.995472] CPU: 11 PID: 28071 Comm: vivid-000-vid-o Tainted: G W 4.20.0-rc1-test-no #88
[174705.995476] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 05/19/2017
[174705.995481] Call Trace:
[174705.995500] dump_stack+0x46/0x60
[174705.995512] ___might_sleep.cold.79+0xe1/0xf1
[174705.995523] __mutex_lock+0x50/0x8f0
[174705.995531] ? find_held_lock+0x2d/0x90
[174705.995536] ? find_held_lock+0x2d/0x90
[174705.995542] ? find_held_lock+0x2d/0x90
[174705.995564] ? v4l2_ctrl_handler_free.part.13+0x44/0x1d0 [videodev]
[174705.995576] v4l2_ctrl_handler_free.part.13+0x44/0x1d0 [videodev]
[174705.995590] v4l2_ctrl_request_release+0x1c/0x30 [videodev]
[174705.995600] media_request_clean+0x64/0xe0 [media]
[174705.995609] media_request_release+0x19/0x40 [media]
[174705.995617] vb2_buffer_done+0xef/0x1d0 [videobuf2_common]
[174705.995630] vivid_thread_vid_out+0x2c1/0x550 [vivid]
[174705.995645] ? vivid_stop_generating_vid_cap+0x1c0/0x1c0 [vivid]
[174705.995653] kthread+0x113/0x130
[174705.995659] ? kthread_park+0x80/0x80
[174705.995667] ret_from_fork+0x35/0x40
The vb2_buffer_done function can be called from interrupt context, so
anything that sleeps is not allowed.
The solution is to increment the request refcount when the buffer is
queued and decrement it when the buffer is dequeued. Releasing the
request is fine if that happens from VIDIOC_DQBUF.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Add ability to track allocated ib_ucontext, which are limited
resource and worth to be visible by users.
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Adding CLK_FRAC_DIVIDER_ZERO_BASED flag to indicate the numerator and
denominator value in register are start from 0.
This can be used to support frac dividers like below:
Divider output clock = Divider input clock x [(frac +1) / (div +1)]
where frac/div in register is:
000b - Divide by 1.
001b - Divide by 2.
010b - Divide by 3.
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Michael Turquette <mturquette@baylibre.com>
Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Pull media fixes from Mauro Carvalho Chehab:
- Revert a dt-bindings patch whose driver didn't make for 4.20
- fix a kernel oops at vicodec driver
- fix a frame overflow at gspca with was causing regressions on some
cameras, making them to not work
- use the proper type for wait_queue head
- make media request API compatible with 32-bit userspace on 64-bit
kernel
- fix a regression on Kernel 4.19 at dvb-pll
- don't use SPDX headers yet for GFDL
* tag 'media/v4.20-4' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
media: mediactl docs: Fix licensing message
media: dvb-pll: don't re-validate tuner frequencies
media: dvb-pll: fix tuner frequency ranges
media: Revert "media: dt-bindings: Document the Rockchip VPU bindings"
media: gspca: fix frame overflow error
media: vicodec: fix memchr() kernel oops
media: cedrus: add action item to the TODO
media: media-request: Add compat ioctl
media: Use wait_queue_head_t for media_request
SPDX-License-Identifier is used for the Xilinx Video IP and
related drivers.
[Added drivers/media/platform/xilinx/Kconfig]
[Added drivers/media/platform/xilinx/Makefile]
[Added include/dt-bindings/media/xilinx-vip.h]
Signed-off-by: Dhaval Shah <dhaval23031987@gmail.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Add device tree bindings for Low Power Audio subsystem clock controller for
Qualcomm Technology Inc's SDM845 SoCs.
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Taniya Das <tdas@codeaurora.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Add flags for Octal mode I/O data transfer
Required for the SPI controller which can do the data transfer (TX/RX)
on 8 data lines e.g. NXP FlexSPI controller.
SPI_TX_OCTAL: transmit with 8 wires
SPI_RX_OCTAL: receive with 8 wires
Signed-off-by: Yogesh Gaur <yogeshnarayan.gaur@nxp.com>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
All of the old arguments can be derived from the uverbs_attr_bundle
structure, so get rid of the redundant arguments. Most of the prior work
has been removing users of the arguments to allow this to be a simple
patch.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
This creates a consistent way to access the two core buffers across write
and write_ex handlers.
Remove the open coded ucore conversion in the write/ex compatibility
handlers.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
When performing single ended measurements with TSCADC, its recommended
to set negative input (SEL_INM_SWC_3_0) of ADC step to ADC's VREFN in the
corresponding STEP_CONFIGx register.
Also, the positive(SEL_RFP_SWC_2_0) and negative(SEL_RFM_SWC_1_0)
reference voltage for ADC step needs to be set to VREFP and VREFN
respectively in STEP_CONFIGx register.
Without these changes, there may be variation of as much as ~2% in the
ADC's digital output which is bad for precise measurement.
Signed-off-by: Vignesh R <vigneshr@ti.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
vmbus_process_offer() mustn't call channel->sc_creation_callback()
directly for sub-channels, because sc_creation_callback() ->
vmbus_open() may never get the host's response to the
OPEN_CHANNEL message (the host may rescind a channel at any time,
e.g. in the case of hot removing a NIC), and vmbus_onoffer_rescind()
may not wake up the vmbus_open() as it's blocked due to a non-zero
vmbus_connection.offer_in_progress, and finally we have a deadlock.
The above is also true for primary channels, if the related device
drivers use sync probing mode by default.
And, usually the handling of primary channels and sub-channels can
depend on each other, so we should offload them to different
workqueues to avoid possible deadlock, e.g. in sync-probing mode,
NIC1's netvsc_subchan_work() can race with NIC2's netvsc_probe() ->
rtnl_lock(), and causes deadlock: the former gets the rtnl_lock
and waits for all the sub-channels to appear, but the latter
can't get the rtnl_lock and this blocks the handling of sub-channels.
The patch can fix the multiple-NIC deadlock described above for
v3.x kernels (e.g. RHEL 7.x) which don't support async-probing
of devices, and v4.4, v4.9, v4.14 and v4.18 which support async-probing
but don't enable async-probing for Hyper-V drivers (yet).
The patch can also fix the hang issue in sub-channel's handling described
above for all versions of kernels, including v4.19 and v4.20-rc4.
So actually the patch should be applied to all the existing kernels,
not only the kernels that have 8195b1396e.
Fixes: 8195b1396e ("hv_netvsc: fix deadlock on hotplug")
Cc: stable@vger.kernel.org
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
