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
code
Clone this repository
https://tangled.org/tjh.dev/kernel
git@gordian.tjh.dev:tjh.dev/kernel
For self-hosted knots, clone URLs may differ based on your setup.
Pull cramfs fix from Al Viro:
"Regression fix, fallen through the cracks"
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
cramfs: fix usage on non-MTD device
Pull last minute virtio bugfixes from Michael Tsirkin:
"Minor bugfixes all over the place"
* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
virtio_balloon: fix shrinker count
virtio_balloon: fix shrinker scan number of pages
virtio_console: allocate inbufs in add_port() only if it is needed
virtio_ring: fix return code on DMA mapping fails
When both CONFIG_CRAMFS_MTD and CONFIG_CRAMFS_BLOCKDEV are enabled, if
we fail to mount on MTD, we don't try on block device.
Note: this relies upon cramfs_mtd_fill_super() leaving no side
effects on fc state in case of failure; in general, failing
get_tree_...() does *not* mean "fine to try again"; e.g. parsed
options might've been consumed by fill_super callback and freed
on failure.
Fixes: 74f78fc5ef43 ("vfs: Convert cramfs to use the new mount API")
Signed-off-by: Maxime Bizon <mbizon@freebox.fr>
Signed-off-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull input fix from Dmitry Torokhov:
"Just a single revert as RMI mode should not have been enabled for this
model [yet?]"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Revert "Input: synaptics - enable RMI mode for X1 Extreme 2nd Generation"
Instead of multiplying by page order, virtio balloon divided by page
order. The result is that it can return 0 if there are a bit less
than MAX_ORDER - 1 pages in use, and then shrinker scan won't be called.
Cc: stable@vger.kernel.org
Fixes: 71994620bb25 ("virtio_balloon: replace oom notifier with shrinker")
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
We need to get the underlying dentry of parent; sure, absent the races
it is the parent of underlying dentry, but there's nothing to prevent
losing a timeslice to preemtion in the middle of evaluation of
lower_dentry->d_parent->d_inode, having another process move lower_dentry
around and have its (ex)parent not pinned anymore and freed on memory
pressure. Then we regain CPU and try to fetch ->d_inode from memory
that is freed by that point.
dentry->d_parent *is* stable here - it's an argument of ->lookup() and
we are guaranteed that it won't be moved anywhere until we feed it
to d_add/d_splice_alias. So we safely go that way to get to its
underlying dentry.
Cc: stable@vger.kernel.org # since 2009 or so
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull networking fixes from David Miller:
1) Validate tunnel options length in act_tunnel_key, from Xin Long.
2) Fix DMA sync bug in gve driver, from Adi Suresh.
3) TSO kills performance on some r8169 chips due to HW issues, disable
by default in that case, from Corinna Vinschen.
4) Fix clock disable mismatch in fec driver, from Chubong Yuan.
5) Fix interrupt status bits define in hns3 driver, from Huazhong Tan.
6) Fix workqueue deadlocks in qeth driver, from Julian Wiedmann.
7) Don't napi_disable() twice in r8152 driver, from Hayes Wang.
8) Fix SKB extension memory leak, from Florian Westphal.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (54 commits)
r8152: avoid to call napi_disable twice
MAINTAINERS: Add myself as maintainer of virtio-vsock
udp: drop skb extensions before marking skb stateless
net: rtnetlink: prevent underflows in do_setvfinfo()
can: m_can_platform: remove unnecessary m_can_class_resume() call
can: m_can_platform: set net_device structure as driver data
hv_netvsc: Fix send_table offset in case of a host bug
hv_netvsc: Fix offset usage in netvsc_send_table()
net-ipv6: IPV6_TRANSPARENT - check NET_RAW prior to NET_ADMIN
sfc: Only cancel the PPS workqueue if it exists
nfc: port100: handle command failure cleanly
net-sysfs: fix netdev_queue_add_kobject() breakage
r8152: Re-order napi_disable in rtl8152_close
net: qca_spi: Move reset_count to struct qcaspi
net: qca_spi: fix receive buffer size check
net/ibmvnic: Ignore H_FUNCTION return from H_EOI to tolerate XIVE mode
Revert "net/ibmvnic: Fix EOI when running in XIVE mode"
net/mlxfw: Verify FSM error code translation doesn't exceed array size
net/mlx5: Update the list of the PCI supported devices
net/mlx5: Fix auto group size calculation
...
This reverts commit 68b9c5066e39af41d3448abfc887c77ce22dd64d.
Ugh, I really dropped the ball on this one :\. So as it turns out RMI4
works perfectly fine on the X1 Extreme Gen 2 except for one thing I
didn't notice because I usually use the trackpoint: clicking with the
touchpad. Somehow this is broken, in fact we don't even seem to indicate
BTN_LEFT as a valid event type for the RMI4 touchpad. And, I don't even
see any RMI4 events coming from the touchpad when I press down on it.
This only seems to work for PS/2 mode.
Since that means we have a regression, and PS/2 mode seems to work fine
for the time being - revert this for now. We'll have to do a more
thorough investigation on this.
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://lore.kernel.org/r/20191119234534.10725-1-lyude@redhat.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
virtio_balloon_shrinker_scan should return number of system pages freed,
but because it's calling functions that deal with balloon pages, it gets
confused and sometimes returns the number of balloon pages.
It does not matter practically as the exact number isn't
used, but it seems better to be consistent in case someone
starts using this API.
Further, if we ever tried to iteratively leak pages as
virtio_balloon_shrinker_scan tries to do, we'd run into issues - this is
because freed_pages was accumulating total freed pages, but was also
subtracted on each iteration from pages_to_free, which can result in
either leaking less memory than we were supposed to free, or more if
pages_to_free underruns.
On a system with 4K pages we are lucky that we are never asked to leak
more than 128 pages while we can leak up to 256 at a time,
but it looks like a real issue for systems with page size != 4K.
Fixes: 71994620bb25 ("virtio_balloon: replace oom notifier with shrinker")
Reported-by: Khazhismel Kumykov <khazhy@google.com>
Reviewed-by: Wei Wang <wei.w.wang@intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
lower_dentry can't go from positive to negative (we have it pinned),
but it *can* go from negative to positive. So fetching ->d_inode
into a local variable, doing a blocking allocation, checking that
now ->d_inode is non-NULL and feeding the value we'd fetched
earlier to a function that won't accept NULL is not a good idea.
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
By default s_maxbytes is set to MAX_NON_LFS, which limits the usable
file size to 2GB, enforced by the vfs.
Commit b9b1f8d5930a ("AFS: write support fixes") added support for the
64-bit fetch and store server operations, but did not change this value.
As a result, attempts to write past the 2G mark result in EFBIG errors:
$ dd if=/dev/zero of=foo bs=1M count=1 seek=2048
dd: error writing 'foo': File too large
Set s_maxbytes to MAX_LFS_FILESIZE.
Fixes: b9b1f8d5930a ("AFS: write support fixes")
Signed-off-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Call napi_disable() twice would cause dead lock. There are three situations
may result in the issue.
1. rtl8152_pre_reset() and set_carrier() are run at the same time.
2. Call rtl8152_set_tunable() after rtl8152_close().
3. Call rtl8152_set_ringparam() after rtl8152_close().
For #1, use the same solution as commit 84811412464d ("r8152: Re-order
napi_disable in rtl8152_close"). For #2 and #3, add checking the flag
of IFF_UP and using napi_disable/napi_enable during mutex.
Signed-off-by: Hayes Wang <hayeswang@realtek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Just got one of these for debugging some unrelated issues, and noticed
that Lenovo seems to have gone back to using RMI4 over smbus with
Synaptics touchpads on some of their new systems, particularly this one.
So, let's enable RMI mode for the X1 Extreme 2nd Generation.
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://lore.kernel.org/r/20191115221814.31903-1-lyude@redhat.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
README