tjh.dev
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1443943
3
927
Clone this repository
https://tangled.org/tjh.dev/kernel
https://tangled.org/did:plc:65gha4t3avpfpzmvpbwovss7/kernel
git@gordian.tjh.dev:tjh.dev/kernel
git@gordian.tjh.dev:did:plc:65gha4t3avpfpzmvpbwovss7/kernel
For self-hosted knots, clone URLs may differ based on your setup.
Download tar.gz
Multiple users have reported their Synaptics touchpad has stopped
working between v4.20.1 and v4.20.2 when using SMBus interface.
The culprit for this appeared to be commit c5eb1190074c ("PCI / PM: Allow
runtime PM without callback functions") that fixed the runtime PM for
i2c-i801 SMBus adapter. Those Synaptics touchpad are using i2c-i801
for SMBus communication and testing showed they are able to get back
working by preventing the runtime suspend of adapter.
Normally when i2c-i801 SMBus adapter transmits with the client it resumes
before operation and autosuspends after.
However, if client requires SMBus Host Notify protocol, what those
Synaptics touchpads do, then the host adapter must not go to runtime
suspend since then it cannot process incoming SMBus Host Notify commands
the client may send.
Fix this by keeping I2C/SMBus adapter active in case client requires
Host Notify.
Reported-by: Keijo Vaara <ferdasyn@rocketmail.com>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=203297
Fixes: c5eb1190074c ("PCI / PM: Allow runtime PM without callback functions")
Cc: stable@vger.kernel.org # v4.20+
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Keijo Vaara <ferdasyn@rocketmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The I2C host driver for SynQuacer fails to populate the of_node and
ACPI companion fields of the struct i2c_adapter it instantiates,
resulting in enumeration of the subordinate I2C bus to fail.
Fixes: 0d676a6c4390 ("i2c: add support for Socionext SynQuacer I2C controller")
Cc: <stable@vger.kernel.org> # v4.19+
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
I haven't heard from Haavard in years despite putting him to the CC list for
i2c-gpio related mails. Since I was doing the work on this driver for a while
now, let me take official maintainership, so it will be more clear to users.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Acked-by: Haavard Skinnemoen <hskinnemoen@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
There are two problems with dev_err() here. One: It is not ratelimited.
Two: We don't see which driver tried to transfer something with a
suspended adapter. Switch to dev_WARN_ONCE to fix both issues. Drawback
is that we don't see if multiple drivers are trying to transfer while
suspended. They need to be discovered one after the other now. This is
better than a high CPU load because a really broken driver might try to
resend endlessly.
Link: https://bugs.archlinux.org/task/62391
Fixes: 275154155538 ("i2c: designware: Do not allow i2c_dw_xfer() calls while suspended")
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reported-by: skidnik <skidnik@gmail.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: skidnik <skidnik@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The way of getting private imx_i2c_struct in i2c_imx_clk_notifier_call()
is incorrect, should use clk_change_nb element to get correct address
and avoid below kernel dump during POST_RATE_CHANGE notify by clk
framework:
Unable to handle kernel paging request at virtual address 03ef1488
pgd = (ptrval)
[03ef1488] *pgd=00000000
Internal error: Oops: 5 [#1] PREEMPT SMP ARM
Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree)
Workqueue: events reduce_bus_freq_handler
PC is at i2c_imx_set_clk+0x10/0xb8
LR is at i2c_imx_clk_notifier_call+0x20/0x28
pc : [<806a893c>] lr : [<806a8a04>] psr: a0080013
sp : bf399dd8 ip : bf3432ac fp : bf7c1dc0
r10: 00000002 r9 : 00000000 r8 : 00000000
r7 : 03ef1480 r6 : bf399e50 r5 : ffffffff r4 : 00000000
r3 : bf025300 r2 : bf399e50 r1 : 00b71b00 r0 : bf399be8
Flags: NzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none
Control: 10c5387d Table: 4e03004a DAC: 00000051
Process kworker/2:1 (pid: 38, stack limit = 0x(ptrval))
Stack: (0xbf399dd8 to 0xbf39a000)
9dc0: 806a89e4 00000000
9de0: ffffffff bf399e50 00000002 806a8a04 806a89e4 80142900 ffffffff 00000000
9e00: bf34ef18 bf34ef04 00000000 ffffffff bf399e50 80142d84 00000000 bf399e6c
9e20: bf34ef00 80f214c4 bf025300 00000002 80f08d08 bf017480 00000000 80142df0
9e40: 00000000 80166ed8 80c27638 8045de58 bf352340 03ef1480 00b71b00 0f82e242
9e60: bf025300 00000002 03ef1480 80f60e5c 00000001 8045edf0 00000002 8045eb08
9e80: bf025300 00000002 03ef1480 8045ee10 03ef1480 8045eb08 bf01be40 00000002
9ea0: 03ef1480 8045ee10 07de2900 8045eb08 bf01b780 00000002 07de2900 8045ee10
9ec0: 80c27898 bf399ee4 bf020a80 00000002 1f78a400 8045ee10 80f60e5c 80460514
9ee0: 80f60e5c bf01b600 bf01b480 80460460 0f82e242 bf383a80 bf383a00 80f60e5c
9f00: 00000000 bf7c1dc0 80f60e70 80460564 80f60df0 80f60d24 80f60df0 8011e72c
9f20: 00000000 80f60df0 80f60e6c bf7c4f00 00000000 8011e7ac bf274000 8013bd84
9f40: bf7c1dd8 80f03d00 bf274000 bf7c1dc0 bf274014 bf7c1dd8 80f03d00 bf398000
9f60: 00000008 8013bfb4 00000000 bf25d100 bf25d0c0 00000000 bf274000 8013bf88
9f80: bf25d11c bf0cfebc 00000000 8014140c bf25d0c0 801412ec 00000000 00000000
9fa0: 00000000 00000000 00000000 801010e8 00000000 00000000 00000000 00000000
9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
9fe0: 00000000 00000000 00000000 00000000 00000013 00000000 00000000 00000000
[<806a893c>] (i2c_imx_set_clk) from [<806a8a04>] (i2c_imx_clk_notifier_call+0x20/0x28)
[<806a8a04>] (i2c_imx_clk_notifier_call) from [<80142900>] (notifier_call_chain+0x44/0x84)
[<80142900>] (notifier_call_chain) from [<80142d84>] (__srcu_notifier_call_chain+0x44/0x98)
[<80142d84>] (__srcu_notifier_call_chain) from [<80142df0>] (srcu_notifier_call_chain+0x18/0x20)
[<80142df0>] (srcu_notifier_call_chain) from [<8045de58>] (__clk_notify+0x78/0xa4)
[<8045de58>] (__clk_notify) from [<8045edf0>] (__clk_recalc_rates+0x60/0xb4)
[<8045edf0>] (__clk_recalc_rates) from [<8045ee10>] (__clk_recalc_rates+0x80/0xb4)
Code: e92d40f8 e5903298 e59072a0 e1530001 (e5975008)
---[ end trace fc7f5514b97b6cbb ]---
Fixes: 90ad2cbe88c2 ("i2c: imx: use clk notifier for rate changes")
Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
Reviewed-by: Dong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
Pull NFS client bugfix from Trond Myklebust:
"Fix a regression in which an RPC call can be tagged with an error
despite the transmission being successful"
* tag 'nfs-for-5.1-5' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
SUNRPC: Ignore queue transmission errors on successful transmission
Pull SCSI fixes from James Bottomley:
"Three minor fixes: two obvious ones in drivers and a fix to the SG_IO
path to correctly return status on error"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: aic7xxx: fix EISA support
Revert "scsi: fcoe: clear FC_RP_STARTED flags when receiving a LOGO"
scsi: core: set result when the command cannot be dispatched
If a request transmission fails due to write space or slot unavailability
errors, but the queued task then gets transmitted before it has time to
process the error in call_transmit_status() or call_bc_transmit_status(),
we need to suppress the transmission error code to prevent it from leaking
out of the RPC layer.
Reported-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Tested-by: Chuck Lever <chuck.lever@oracle.com>
Pull block fixes from Jens Axboe:
"A set of small fixes that should go into this series. This contains:
- Removal of unused queue member (Hou)
- Overflow bvec fix (Ming)
- Various little io_uring tweaks (me)
- kthread parking
- Only call cpu_possible() for verified CPU
- Drop unused 'file' argument to io_file_put()
- io_uring_enter vs io_uring_register deadlock fix
- CQ overflow fix
- BFQ internal depth update fix (me)"
* tag 'for-linus-20190420' of git://git.kernel.dk/linux-block:
block: make sure that bvec length can't be overflow
block: kill all_q_node in request_queue
io_uring: fix CQ overflow condition
io_uring: fix possible deadlock between io_uring_{enter,register}
io_uring: drop io_file_put() 'file' argument
bfq: update internal depth state when queue depth changes
io_uring: only test SQPOLL cpu after we've verified it
io_uring: park SQPOLL thread if it's percpu
Instead of relying on the now removed NULL argument to
pci_alloc_consistent, switch to the generic DMA API, and store the struct
device so that we can pass it.
Fixes: 4167b2ad5182 ("PCI: Remove NULL device handling from PCI DMA API")
Reported-by: Matthew Whitehead <tedheadster@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Matthew Whitehead <tedheadster@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Pill i3c fixes from Boris Brezillon:
- fix the random PID check
- fix the disable controller logic in the designware driver
- fix I3C entry in MAINTAINERS
* tag 'i3c/fixes-for-5.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux:
MAINTAINERS: Fix the I3C entry
i3c: dw: Fix dw_i3c_master_disable controller by using correct mask
i3c: Fix the verification of random PID
README