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
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Pull bcachefs fixes from Kent Overstreet:
"Some more mostly boring fixes, but some not
User reported ones:
- the BTREE_ITER_FILTER_SNAPSHOTS one fixes a really nasty
performance bug; user reported an untar initially taking two
seconds and then ~2 minutes
- kill a __GFP_NOFAIL in the buffered read path; this was a leftover
from the trickier fix to kill __GFP_NOFAIL in readahead, where we
can't return errors (and have to silently truncate the read
ourselves).
bcachefs can't use GFP_NOFAIL for folio state unlike iomap based
filesystems because our folio state is just barely too big, 2MB
hugepages cause us to exceed the 2 page threshhold for GFP_NOFAIL.
additionally, the flags argument was just buggy, we weren't
supplying GFP_KERNEL previously (!)"
* tag 'bcachefs-2024-02-25' of https://evilpiepirate.org/git/bcachefs:
bcachefs: fix bch2_save_backtrace()
bcachefs: Fix check_snapshot() memcpy
bcachefs: Fix bch2_journal_flush_device_pins()
bcachefs: fix iov_iter count underflow on sub-block dio read
bcachefs: Fix BTREE_ITER_FILTER_SNAPSHOTS on inodes btree
bcachefs: Kill __GFP_NOFAIL in buffered read path
bcachefs: fix backpointer_to_text() when dev does not exist
Pull two documentation build fixes from Jonathan Corbet:
- The XFS online fsck documentation uses incredibly deeply nested
subsection and list nesting; that broke the PDF docs build. Tweak a
parameter to tell LaTeX to allow the deeper nesting.
- Fix a 6.8 PDF-build regression
* tag 'docs-6.8-fixes3' of git://git.lwn.net/linux:
docs: translations: use attribute to store current language
docs: Instruct LaTeX to cope with deeper nesting
Missed a call in the previous fix.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Pull USB fixes from Greg KH:
"Here are some small USB fixes for 6.8-rc6 to resolve some reported
problems. These include:
- regression fixes with typec tpcm code as reported by many
- cdnsp and cdns3 driver fixes
- usb role setting code bugfixes
- build fix for uhci driver
- ncm gadget driver bugfix
- MAINTAINERS entry update
All of these have been in linux-next all week with no reported issues
and there is at least one fix in here that is in Thorsten's regression
list that is being tracked"
* tag 'usb-6.8-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
usb: typec: tpcm: Fix issues with power being removed during reset
MAINTAINERS: Drop myself as maintainer of TYPEC port controller drivers
usb: gadget: ncm: Avoid dropping datagrams of properly parsed NTBs
Revert "usb: typec: tcpm: reset counter when enter into unattached state after try role"
usb: gadget: omap_udc: fix USB gadget regression on Palm TE
usb: dwc3: gadget: Don't disconnect if not started
usb: cdns3: fix memory double free when handle zero packet
usb: cdns3: fixed memory use after free at cdns3_gadget_ep_disable()
usb: roles: don't get/set_role() when usb_role_switch is unregistered
usb: roles: fix NULL pointer issue when put module's reference
usb: cdnsp: fixed issue with incorrect detecting CDNSP family controllers
usb: cdnsp: blocked some cdns3 specific code
usb: uhci-grlib: Explicitly include linux/platform_device.h
Akira Yokosawa reported [1] that the "translations" extension we added in
commit 7418ec5b151f ("docs: translations: add translations links when they
exist") broke the build on Sphinx versions v6.1.3 through 7.1.2 (possibly
others) with the following error:
Exception occurred:
File "/usr/lib/python3.12/site-packages/sphinx/util/nodes.py", line 624, in _copy_except__document
newnode = self.__class__(rawsource=self.rawsource, **self.attributes)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
TypeError: LanguagesNode.__init__() missing 1 required positional argument: 'current_language'
The full traceback has been saved in /tmp/sphinx-err-7xmwytuu.log, if you want to report the issue to the developers.
Solve this problem by making 'current_language' a true element attribute
of the LanguagesNode element, which is probably the more correct way to do
it anyway.
Tested on Sphinx 2.x, 3.x, 6.x, and 7.x.
[1]: https://lore.kernel.org/all/54a56c2e-a27c-45a0-b712-02a7bc7d2673@gmail.com/
Fixes: 7418ec5b151f ("docs: translations: add translations links when they exist")
Reported-by: Akira Yokosawa <akiyks@gmail.com>
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Closes: https://lore.kernel.org/all/54a56c2e-a27c-45a0-b712-02a7bc7d2673@gmail.com/
Tested-by: Akira Yokosawa <akiyks@gmail.com> # Sphinx 4.3.2, 5.3.0 and 6.2.1
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Link: https://lore.kernel.org/r/20240215064109.1193556-1-vegard.nossum@oracle.com
check_snapshot() copies the bch_snapshot to a temporary to easily handle
older versions that don't have all the fields of the current version,
but it lacked a min() to correctly handle keys newer and larger than the
current version.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Pull tty/serial driver fixes from Greg KH:
"Here are three small serial/tty driver fixes for 6.8-rc6 that resolve
the following reported errors:
- riscv hvc console driver fix that was reported by many
- amba-pl011 serial driver fix for RS485 mode
- stm32 serial driver fix for RS485 mode
All of these have been in linux-next all week with no reported
problems"
* tag 'tty-6.8-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
serial: amba-pl011: Fix DMA transmission in RS485 mode
serial: stm32: do not always set SER_RS485_RX_DURING_TX if RS485 is enabled
tty: hvc: Don't enable the RISC-V SBI console by default
Since the merge of b717dfbf73e8 ("Revert "usb: typec: tcpm: fix
cc role at port reset"") into mainline the LibreTech Renegade
Elite/Firefly has died during boot, the main symptom observed in testing
is a sudden stop in console output. Gábor Stefanik identified in review
that the patch would cause power to be removed from devices without
batteries (like this board), observing that while the patch is correct
according to the spec this appears to be an oversight in the spec.
Given that the change makes previously working systems unusable let's
revert it, there was some discussion of identifying systems that have
alternative power and implementing the standards conforming behaviour in
only that case.
Fixes: b717dfbf73e8 ("Revert "usb: typec: tcpm: fix cc role at port reset"")
Cc: stable <stable@kernel.org>
Cc: Badhri Jagan Sridharan <badhri@google.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20240212-usb-fix-renegade-v1-1-22c43c88d635@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The addition of the XFS online fsck documentation starting with
commit a8f6c2e54ddc ("xfs: document the motivation for online fsck design")
added a deeper level of nesting than LaTeX is prepared to deal with. That
caused a pdfdocs build failure with the helpful "Too deeply nested" error
message buried deeply in Documentation/output/filesystems.log.
Increase the "maxlistdepth" parameter to instruct LaTeX that it needs to
deal with the deeper nesting whether it wants to or not.
Suggested-by: Akira Yokosawa <akiyks@gmail.com>
Tested-by: Akira Yokosawa <akiyks@gmail.com>
Cc: stable@vger.kernel.org # v6.4+
Link: https://lore.kernel.org/linux-doc/67f6ac60-7957-4b92-9d72-a08fbad0e028@gmail.com/
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
If a journal write errored, the list of devices it was written to could
be empty - we're not supposed to mark an empty replicas list.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Pull x86 fixes from Borislav Petkov:
- Make sure clearing CPU buffers using VERW happens at the latest
possible point in the return-to-userspace path, otherwise memory
accesses after the VERW execution could cause data to land in CPU
buffers again
* tag 'x86_urgent_for_v6.8_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
KVM/VMX: Move VERW closer to VMentry for MDS mitigation
KVM/VMX: Use BT+JNC, i.e. EFLAGS.CF to select VMRESUME vs. VMLAUNCH
x86/bugs: Use ALTERNATIVE() instead of mds_user_clear static key
x86/entry_32: Add VERW just before userspace transition
x86/entry_64: Add VERW just before userspace transition
x86/bugs: Add asm helpers for executing VERW
When DMA is used in RS485 mode make sure that the UARTs tx section is
enabled before the DMA buffers are queued for transmission.
Cc: stable@vger.kernel.org
Fixes: 8d479237727c ("serial: amba-pl011: add RS485 support")
Signed-off-by: Lino Sanfilippo <l.sanfilippo@kunbus.com>
Link: https://lore.kernel.org/r/20240216224709.9928-2-l.sanfilippo@kunbus.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
I am no longer involved in Type-C development and not really current on its
status and progress. Recently I have been doing more damage than good.
It is time to go.
Cc: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20240215202039.1982539-1-linux@roeck-us.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If the directory passed to the '.. kernel-feat::' directive does not
exist or the get_feat.pl script does not find any files to extract
features from, Sphinx will report the following error:
Sphinx parallel build error:
UnboundLocalError: local variable 'fname' referenced before assignment
make[2]: *** [Documentation/Makefile:102: htmldocs] Error 2
This is due to how I changed the script in c48a7c44a1d0 ("docs:
kernel_feat.py: fix potential command injection"). Before that, the
filename passed along to self.nestedParse() in this case was weirdly
just the whole get_feat.pl invocation.
We can fix it by doing what kernel_abi.py does -- just pass
self.arguments[0] as 'fname'.
Fixes: c48a7c44a1d0 ("docs: kernel_feat.py: fix potential command injection")
Cc: Justin Forbes <jforbes@fedoraproject.org>
Cc: Salvatore Bonaccorso <carnil@debian.org>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Link: https://lore.kernel.org/r/20240205175133.774271-2-vegard.nossum@oracle.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
bch2_direct_IO_read() checks the request offset and size for sector
alignment and then falls through to a couple calculations to shrink
the size of the request based on the inode size. The problem is that
these checks round up to the fs block size, which runs the risk of
underflowing iter->count if the block size happens to be large
enough. This is triggered by fstest generic/361 with a 4k block
size, which subsequently leads to a crash. To avoid this crash,
check that the shorten length doesn't exceed the overall length of
the iter.
Fixes:
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Su Yue <glass.su@suse.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
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