Linux kernel
============
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In order to build the documentation, use ``make htmldocs`` or
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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.
See Documentation/00-INDEX for a list of what is contained in each file.
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.
code
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Pull btrfs fixes from David Sterba:
"We have a few regression fixes for qgroup rescan status tracking and
the vm_fault_t conversion that mixed up the error values"
* tag 'for-4.18-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
Btrfs: fix mount failure when qgroup rescan is in progress
Btrfs: fix regression in btrfs_page_mkwrite() from vm_fault_t conversion
btrfs: quota: Set rescan progress to (u64)-1 if we hit last leaf
Pull vfs fix from Al Viro:
"Followup to procfs-seq_file series this window"
This fixes a memory leak by making sure that proc seq files release any
private data on close. The 'proc_seq_open' has to be properly paired
with 'proc_seq_release' that releases the extra private data.
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
proc: add proc_seq_release
If a power failure happens while the qgroup rescan kthread is running,
the next mount operation will always fail. This is because of a recent
regression that makes qgroup_rescan_init() incorrectly return -EINVAL
when we are mounting the filesystem (through btrfs_read_qgroup_config()).
This causes the -EINVAL error to be returned regardless of any qgroup
flags being set instead of returning the error only when neither of
the flags BTRFS_QGROUP_STATUS_FLAG_RESCAN nor BTRFS_QGROUP_STATUS_FLAG_ON
are set.
A test case for fstests follows up soon.
Fixes: 9593bf49675e ("btrfs: qgroup: show more meaningful qgroup_rescan_init error message")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pull staging/IIO fixes from Greg KH:
"Here are a few small staging and IIO driver fixes for 4.18-rc3.
Nothing major or big, all just fixes for reported problems since
4.18-rc1. All of these have been in linux-next this week with no
reported problems"
* tag 'staging-4.18-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
staging: android: ion: Return an ERR_PTR in ion_map_kernel
staging: comedi: quatech_daqp_cs: fix no-op loop daqp_ao_insn_write()
iio: imu: inv_mpu6050: Fix probe() failure on older ACPI based machines
iio: buffer: fix the function signature to match implementation
iio: mma8452: Fix ignoring MMA8452_INT_DRDY
iio: tsl2x7x/tsl2772: avoid potential division by zero
iio: pressure: bmp280: fix relative humidity unit
kmemleak reported some memory leak on reading proc files. After adding
some debug lines, find that proc_seq_fops is using seq_release as
release handler, which won't handle the free of 'private' field of
seq_file, while in fact the open handler proc_seq_open could create
the private data with __seq_open_private when state_size is greater
than zero. So after reading files created with proc_create_seq_private,
such as /proc/timer_list and /proc/vmallocinfo, the private mem of a
seq_file is not freed. Fix it by adding the paired proc_seq_release
as the default release handler of proc_seq_ops instead of seq_release.
Fixes: 44414d82cfe0 ("proc: introduce proc_create_seq_private")
Reviewed-by: Christoph Hellwig <hch@lst.de>
CC: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chunyu Hu <chuhu@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The vm_fault_t conversion commit introduced a ret2 variable for tracking
the integer return values from internal btrfs functions. It was
sometimes returning VM_FAULT_LOCKED for pages that were actually invalid
and had been removed from the radix. Something like this:
ret2 = btrfs_delalloc_reserve_space() // returns zero on success
lock_page(page)
if (page->mapping != inode->i_mapping)
goto out_unlock;
...
out_unlock:
if (!ret2) {
...
return VM_FAULT_LOCKED;
}
This ends up triggering this WARNING in btrfs_destroy_inode()
WARN_ON(BTRFS_I(inode)->block_rsv.size);
xfstests generic/095 was able to reliably reproduce the errors.
Since out_unlock: is only used for errors, this fix moves it below the
if (!ret2) check we use to return VM_FAULT_LOCKED for success.
Fixes: a528a2415087 (btrfs: change return type of btrfs_page_mkwrite to vm_fault_t)
Signed-off-by: Chris Mason <clm@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pull tty/serial fixes from Greg KH:
"Here are five fixes for the tty core and some serial drivers.
The tty core ones fix some security and other issues reported by the
syzbot that I have taken too long in responding to (sorry Tetsuo!).
The 8350 serial driver fix resolves an issue of devices that used to
work properly stopping working as they shouldn't have been added to a
blacklist.
All of these have been in linux-next for a few days with no reported
issues"
* tag 'tty-4.18-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
vt: prevent leaking uninitialized data to userspace via /dev/vcs*
serdev: fix memleak on module unload
serial: 8250_pci: Remove stalled entries in blacklist
n_tty: Access echo_* variables carefully.
n_tty: Fix stall at n_tty_receive_char_special().
Jonathan writes:
First set of IIO fixes for the 4.18 cycle.
* bmp280
- Fix wrong relative humidity unit.
* buffer
- Fix a function signature to match the function.
* inv_mpu6050
- Fix a regression in which older ACPI devices won't have working
interrupts due to lack of information on the interrupt type.
* mma8452
- Don't ignore data ready interrupt when handling interrupts as will
look like an unhandled interrupt.
* tsl2x7x/tsl2772
- Avoid a potential division by zero.
Commit ff3d27a048d9 ("btrfs: qgroup: Finish rescan when hit the last leaf
of extent tree") added a new exit for rescan finish.
However after finishing quota rescan, we set
fs_info->qgroup_rescan_progress to (u64)-1 before we exit through the
original exit path.
While we missed that assignment of (u64)-1 in the new exit path.
The end result is, the quota status item doesn't have the same value.
(-1 vs the last bytenr + 1)
Although it doesn't affect quota accounting, it's still better to keep
the original behavior.
Reported-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Fixes: ff3d27a048d9 ("btrfs: qgroup: Finish rescan when hit the last leaf of extent tree")
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Pull USB fixes from Greg KH:
"Here is a number of USB gadget and other driver fixes for 4.18-rc3.
There's a bunch of them here, most of them being gadget driver and
xhci host controller fixes for reported issues (as normal), but there
are also some new device ids, and some fixes for the typec code.
There is an acpi core patch in here that was acked by the acpi
maintainer as it is needed for the typec fixes in order to properly
solve a problem in that driver.
All of these have been in linux-next this week with no reported
issues"
* tag 'usb-4.18-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (33 commits)
usb: chipidea: host: fix disconnection detect issue
usb: typec: tcpm: fix logbuffer index is wrong if _tcpm_log is re-entered
typec: tcpm: Fix a msecs vs jiffies bug
NFC: pn533: Fix wrong GFP flag usage
usb: cdc_acm: Add quirk for Uniden UBC125 scanner
staging/typec: fix tcpci_rt1711h build errors
usb: typec: ucsi: Fix for incorrect status data issue
usb: typec: ucsi: acpi: Workaround for cache mode issue
acpi: Add helper for deactivating memory region
usb: xhci: increase CRS timeout value
usb: xhci: tegra: fix runtime PM error handling
usb: xhci: remove the code build warning
xhci: Fix kernel oops in trace_xhci_free_virt_device
xhci: Fix perceived dead host due to runtime suspend race with event handler
dwc2: gadget: Fix ISOC IN DDMA PID bitfield value calculation
usb: gadget: dwc2: fix memory leak in gadget_init()
usb: gadget: composite: fix delayed_status race condition when set_interface
usb: dwc2: fix isoc split in transfer with no data
usb: dwc2: alloc dma aligned buffer for isoc split in
usb: dwc2: fix the incorrect bitmaps for the ports of multi_tt hub
...
KMSAN reported an infoleak when reading from /dev/vcs*:
BUG: KMSAN: kernel-infoleak in vcs_read+0x18ba/0x1cc0
Call Trace:
...
kmsan_copy_to_user+0x7a/0x160 mm/kmsan/kmsan.c:1253
copy_to_user ./include/linux/uaccess.h:184
vcs_read+0x18ba/0x1cc0 drivers/tty/vt/vc_screen.c:352
__vfs_read+0x1b2/0x9d0 fs/read_write.c:416
vfs_read+0x36c/0x6b0 fs/read_write.c:452
...
Uninit was created at:
kmsan_save_stack_with_flags mm/kmsan/kmsan.c:279
kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:189
kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:315
__kmalloc+0x13a/0x350 mm/slub.c:3818
kmalloc ./include/linux/slab.h:517
vc_allocate+0x438/0x800 drivers/tty/vt/vt.c:787
con_install+0x8c/0x640 drivers/tty/vt/vt.c:2880
tty_driver_install_tty drivers/tty/tty_io.c:1224
tty_init_dev+0x1b5/0x1020 drivers/tty/tty_io.c:1324
tty_open_by_driver drivers/tty/tty_io.c:1959
tty_open+0x17b4/0x2ed0 drivers/tty/tty_io.c:2007
chrdev_open+0xc25/0xd90 fs/char_dev.c:417
do_dentry_open+0xccc/0x1440 fs/open.c:794
vfs_open+0x1b6/0x2f0 fs/open.c:908
...
Bytes 0-79 of 240 are uninitialized
Consistently allocating |vc_screenbuf| with kzalloc() fixes the problem
Reported-by: syzbot+17a8efdf800000@syzkaller.appspotmail.com
Signed-off-by: Alexander Potapenko <glider@google.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The expected return value from ion_map_kernel is an ERR_PTR. The error
path for a vmalloc failure currently just returns NULL, triggering
a warning in ion_buffer_kmap_get. Encode the vmalloc failure as an ERR_PTR.
Reported-by: syzbot+55b1d9f811650de944c6@syzkaller.appspotmail.com
Signed-off-by: Laura Abbott <labbott@redhat.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Commit 5ec6486daa98 ("iio:imu: inv_mpu6050: support more interrupt types")
causes inv_mpu_core_probe() to fail if the IRQ does not have a
trigger-type setup.
This happens on machines where the mpu6050 is enumerated through ACPI and
an older Interrupt type ACPI resource is used for the interrupt, rather
then a GpioInt type type, causing the mpu6050 driver to no longer work
there. This happens on e.g. the Asus T100TA.
This commits makes the mpu6050 fallback to the old IRQF_TRIGGER_RISING
default if the irq-type is not setup, fixing this.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Fixes: 5ec6486daa98 ("iio:imu: inv_mpu6050: support more interrupt types")
Reviewed-by: Martin Kelly <mkelly@xevo.com>
Reviewed-by: Jean-Baptiste Maneyrol <jmaneyrol@invensense.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>