Device drivers usually depend on the fact that the devices that they
control are suspended in the same order that they were probed in. In
most cases this is already guaranteed via deferred probe.
However, there's one case where this can still break: if a device is
instantiated before a dependency (for example if it appears before the
dependency in device tree) but gets probed only after the dependency is
probed. Instantiation order would cause the dependency to get probed
later, in which case probe of the original device would be deferred and
the suspend/resume queue would get reordered properly. However, if the
dependency is provided by a built-in driver and the device depending on
that driver is controlled by a loadable module, which may only get
loaded after the root filesystem has become available, we can be faced
with a situation where the probe order ends up being different from the
suspend/resume order.
One example where this happens is on Tegra186, where the ACONNECT is
listed very early in device tree (sorted by unit-address) and depends on
BPMP (listed very late because it has no unit-address) for power domains
and clocks/resets. If the ACONNECT driver is built-in, there is no
problem because it will be probed before BPMP, causing a probe deferral
and that in turn reorders the suspend/resume queue. However, if built as
a module, it will end up being probed after BPMP, and therefore not
result in a probe deferral, and therefore the suspend/resume queue will
stay in the instantiation order. This in turn causes problems because
ACONNECT will be resumed before BPMP, which will result in a hang
because the ACONNECT's power domain cannot be powered on as long as the
BPMP is still suspended.
Fix this by always reordering devices on successful probe. This ensures
that the suspend/resume queue is always in probe order and hence meets
the natural expectations of drivers vs. their dependencies.
Reported-by: Jonathan Hunter <jonathanh@nvidia.com>
Acked-by: Rafael. J. Wysocki <rafael@kernel.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20201203175756.1405564-1-thierry.reding@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The current implementation of fw_devlink is very inefficient because it
tries to get away without creating fwnode links in the name of saving
memory usage. Past attempts to optimize runtime at the cost of memory
usage were blocked with request for data showing that the optimization
made significant improvement for real world scenarios.
We have those scenarios now. There have been several reports of boot
time increase in the order of seconds in this thread [1]. Several OEMs
and SoC manufacturers have also privately reported significant
(350-400ms) increase in boot time due to all the parsing done by
fw_devlink.
So this patch uses all the setup done by the previous patches in this
series to refactor fw_devlink to be more efficient. Most of the code has
been moved out of firmware specific (DT mostly) code into driver core.
This brings the following benefits:
- Instead of parsing the device tree multiple times during bootup,
fw_devlink parses each fwnode node/property only once and creates
fwnode links. The rest of the fw_devlink code then just looks at these
fwnode links to do rest of the work.
- Makes it much easier to debug probe issue due to fw_devlink in the
future. fw_devlink=on blocks the probing of devices if they depend on
a device that hasn't been added yet. With this refactor, it'll be very
easy to tell what that device is because we now have a reference to
the fwnode of the device.
- Much easier to add fw_devlink support to ACPI and other firmware
types. A refactor to move the common bits from DT specific code to
driver core was in my TODO list as a prerequisite to adding ACPI
support to fw_devlink. This series gets that done.
[1] - https://lore.kernel.org/linux-omap/ea02f57e-871d-cd16-4418-c1da4bbc4696@ti.com/
Tested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Tested-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20201121020232.908850-17-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To check if a device is still waiting for its supplier devices to be
added, we used to check if the devices is in a global
waiting_for_suppliers list. Since the global list will be deleted in
subsequent patches, this patch stops using this check.
Instead, this patch uses a more device specific check. It checks if the
device's fwnode has any fwnode links that haven't been converted to
device links yet.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20201121020232.908850-14-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This function is a wrapper around fwnode_operations.add_links().
This function parses each node in a fwnode tree and create fwnode links
for each of those nodes. The information for creating the fwnode links
(the supplier and consumer fwnode) is obtained by parsing the properties
in each of the fwnodes.
This function also ensures that no fwnode is parsed more than once by
marking the fwnodes as parsed.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20201121020232.908850-13-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Change the meaning of fwnode_operations.add_links() to just create
fwnode links by parsing the properties of a given fwnode.
This patch doesn't actually make any code changes. To keeps things more
digestable, the actual functional changes come in later patches in this
series.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20201121020232.908850-12-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add fwnode_is_ancestor_of() helper function to check if a fwnode is an
ancestor of another fwnode.
Add fwnode_get_next_parent_dev() helper function that take as input a
fwnode and finds the closest ancestor fwnode that has a corresponding
struct device and returns that struct device.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20201121020232.908850-11-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
SYNC_STATE_ONLY device links only affect the behavior of sync_state()
callbacks. Specifically, they prevent sync_state() only callbacks from
being called on a device if one or more of its consumers haven't probed.
So, creating a SYNC_STATE_ONLY device link from an already probed
consumer is useless. So, don't allow creating such device links.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20201121020232.908850-10-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit 716a7a2596.
The fw_devlink_pause/resume() APIs added by the commit being reverted
were a first cut attempt at optimizing boot time. But these APIs don't
fully solve the problem and are very fragile (can only be used for the
top level devices being added). This series replaces them with a much
better optimization that works for all device additions and also has the
benefit of reducing the complexity of the firmware (DT, EFI) specific
code and abstracting out common code to driver core.
Signed-off-by: Saravana Kannan <saravanak@google.com>
Link: https://lore.kernel.org/r/20201121020232.908850-7-saravanak@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The device_links_purge() function (called from device_del()) tries to
remove the links.needs_suppliers list entry, but it's using
list_del(), hence it doesn't initialize after the removal. This is OK
for normal cases where device_del() is called via device_destroy().
However, it's not guaranteed that the device object will be really
deleted soon after device_del(). In a minor case like HD-audio codec
reconfiguration that re-initializes the device after device_del(), it
may lead to a crash by the corrupted list entry.
As a simple fix, replace list_del() with list_del_init() in order to
make the list intact after the device_del() call.
Fixes: e2ae9bcc4a ("driver core: Add support for linking devices during device addition")
Cc: <stable@vger.kernel.org>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/20201208190326.27531-1-tiwai@suse.de
Cc: Saravana Kannan <saravanak@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Specify type alignment when declaring linker-section match-table entries
to prevent gcc from increasing alignment and corrupting the various
tables with padding (e.g. timers, irqchips, clocks, reserved memory).
This is specifically needed on x86 where gcc (typically) aligns larger
objects like struct of_device_id with static extent on 32-byte
boundaries which at best prevents matching on anything but the first
entry. Specifying alignment when declaring variables suppresses this
optimisation.
Here's a 64-bit example where all entries are corrupt as 16 bytes of
padding has been inserted before the first entry:
ffffffff8266b4b0 D __clk_of_table
ffffffff8266b4c0 d __of_table_fixed_factor_clk
ffffffff8266b5a0 d __of_table_fixed_clk
ffffffff8266b680 d __clk_of_table_sentinel
And here's a 32-bit example where the 8-byte-aligned table happens to be
placed on a 32-byte boundary so that all but the first entry are corrupt
due to the 28 bytes of padding inserted between entries:
812b3ec0 D __irqchip_of_table
812b3ec0 d __of_table_irqchip1
812b3fa0 d __of_table_irqchip2
812b4080 d __of_table_irqchip3
812b4160 d irqchip_of_match_end
Verified on x86 using gcc-9.3 and gcc-4.9 (which uses 64-byte
alignment), and on arm using gcc-7.2.
Note that there are no in-tree users of these tables on x86 currently
(even if they are included in the image).
Fixes: 54196ccbe0 ("of: consolidate linker section OF match table declarations")
Fixes: f6e916b820 ("irqchip: add basic infrastructure")
Cc: stable <stable@vger.kernel.org> # 3.9
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20201123102319.8090-2-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Auxiliary Bus support tag for 5.11-rc1
This is a signed tag for other subsystems to be able to pull in the
auxiliary bus support into their trees for the 5.11-rc1 merge.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull driver core documentation fixes from Greg KH:
"Some small Documentation fixes that were fallout from the larger
documentation update we did in 5.10-rc2.
Nothing major here at all, but all of these have been in linux-next
and resolve build warnings when building the documentation files"
* tag 'driver-core-5.10-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
Documentation: remove mic/index from misc-devices/index.rst
scripts: get_api.pl: Add sub-titles to ABI output
scripts: get_abi.pl: Don't let ABI files to create subtitles
docs: leds: index.rst: add a missing file
docs: ABI: sysfs-class-net: fix a typo
docs: ABI: sysfs-driver-dma-ioatdma: what starts with /sys
Pull tty/serial fixes from Greg KH:
"Here are a small number of small tty and serial fixes for some
reported problems for the tty core, vt code, and some serial drivers.
They include fixes for:
- a buggy and obsolete vt font ioctl removal
- 8250_mtk serial baudrate runtime warnings
- imx serial earlycon build configuration fix
- txx9 serial driver error path cleanup issues
- tty core fix in release_tty that can be triggered by trying to bind
an invalid serial port name to a speakup console device
Almost all of these have been in linux-next without any problems, the
only one that hasn't, just deletes code :)"
* tag 'tty-5.10-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
vt: Disable KD_FONT_OP_COPY
tty: fix crash in release_tty if tty->port is not set
serial: txx9: add missing platform_driver_unregister() on error in serial_txx9_init
tty: serial: imx: enable earlycon by default if IMX_SERIAL_CONSOLE is enabled
serial: 8250_mtk: Fix uart_get_baud_rate warning
Pull USB fixes from Greg KH:
"Here are some small USB fixes and new device ids:
- USB gadget fixes for some reported issues
- Fixes for the ever-troublesome apple fastcharge driver, hopefully
we finally have it right.
- More USB core quirks for odd devices
- USB serial driver fixes for some long-standing issues that were
recently found
- some new USB serial driver device ids
All have been in linux-next with no reported issues"
* tag 'usb-5.10-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
USB: apple-mfi-fastcharge: fix reference leak in apple_mfi_fc_set_property
usb: mtu3: fix panic in mtu3_gadget_stop()
USB: serial: option: add Telit FN980 composition 0x1055
USB: serial: option: add LE910Cx compositions 0x1203, 0x1230, 0x1231
USB: serial: cyberjack: fix write-URB completion race
USB: Add NO_LPM quirk for Kingston flash drive
USB: serial: option: add Quectel EC200T module support
usb: raw-gadget: fix memory leak in gadget_setup
usb: dwc2: Avoid leaving the error_debugfs label unused
usb: dwc3: ep0: Fix delay status handling
usb: gadget: fsl: fix null pointer checking
usb: gadget: goku_udc: fix potential crashes in probe
usb: dwc3: pci: add support for the Intel Alder Lake-S
current->group_leader->exit_signal may change during copy_process() if
current->real_parent exits.
Move the assignment inside tasklist_lock to avoid the race.
Signed-off-by: Eddy Wu <eddy_wu@trendmicro.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It's buggy:
On Fri, Nov 06, 2020 at 10:30:08PM +0800, Minh Yuan wrote:
> We recently discovered a slab-out-of-bounds read in fbcon in the latest
> kernel ( v5.10-rc2 for now ). The root cause of this vulnerability is that
> "fbcon_do_set_font" did not handle "vc->vc_font.data" and
> "vc->vc_font.height" correctly, and the patch
> <https://lkml.org/lkml/2020/9/27/223> for VT_RESIZEX can't handle this
> issue.
>
> Specifically, we use KD_FONT_OP_SET to set a small font.data for tty6, and
> use KD_FONT_OP_SET again to set a large font.height for tty1. After that,
> we use KD_FONT_OP_COPY to assign tty6's vc_font.data to tty1's vc_font.data
> in "fbcon_do_set_font", while tty1 retains the original larger
> height. Obviously, this will cause an out-of-bounds read, because we can
> access a smaller vc_font.data with a larger vc_font.height.
Further there was only one user ever.
- Android's loadfont, busybox and console-tools only ever use OP_GET
and OP_SET
- fbset documentation only mentions the kernel cmdline font: option,
not anything else.
- systemd used OP_COPY before release 232 published in Nov 2016
Now unfortunately the crucial report seems to have gone down with
gmane, and the commit message doesn't say much. But the pull request
hints at OP_COPY being broken
https://github.com/systemd/systemd/pull/3651
So in other words, this never worked, and the only project which
foolishly every tried to use it, realized that rather quickly too.
Instead of trying to fix security issues here on dead code by adding
missing checks, fix the entire thing by removing the functionality.
Note that systemd code using the OP_COPY function ignored the return
value, so it doesn't matter what we're doing here really - just in
case a lone server somewhere happens to be extremely unlucky and
running an affected old version of systemd. The relevant code from
font_copy_to_all_vcs() in systemd was:
/* copy font from active VT, where the font was uploaded to */
cfo.op = KD_FONT_OP_COPY;
cfo.height = vcs.v_active-1; /* tty1 == index 0 */
(void) ioctl(vcfd, KDFONTOP, &cfo);
Note this just disables the ioctl, garbage collecting the now unused
callbacks is left for -next.
v2: Tetsuo found the old mail, which allowed me to find it on another
archive. Add the link too.
Acked-by: Peilin Ye <yepeilin.cs@gmail.com>
Reported-by: Minh Yuan <yuanmingbuaa@gmail.com>
References: https://lists.freedesktop.org/archives/systemd-devel/2016-June/036935.html
References: https://github.com/systemd/systemd/pull/3651
Cc: Greg KH <greg@kroah.com>
Cc: Peilin Ye <yepeilin.cs@gmail.com>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://lore.kernel.org/r/20201108153806.3140315-1-daniel.vetter@ffwll.ch
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull xfs fixes from Darrick Wong:
- Fix an uninitialized struct problem
- Fix an iomap problem zeroing unwritten EOF blocks
- Fix some clumsy error handling when writeback fails on filesystems
with blocksize < pagesize
- Fix a retry loop not resetting loop variables properly
- Fix scrub flagging rtinherit inodes on a non-rt fs, since the kernel
actually does permit that combination
- Fix excessive page cache flushing when unsharing part of a file
* tag 'xfs-5.10-fixes-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
xfs: only flush the unshared range in xfs_reflink_unshare
xfs: fix scrub flagging rtinherit even if there is no rt device
xfs: fix missing CoW blocks writeback conversion retry
iomap: clean up writeback state logic on writepage error
iomap: support partial page discard on writeback block mapping failure
xfs: flush new eof page on truncate to avoid post-eof corruption
xfs: set xefi_discard when creating a deferred agfl free log intent item
Merge procfs splice read fixes from Christoph Hellwig:
"Greg reported a problem due to the fact that Android tests use procfs
files to test splice, which stopped working with the changes for
set_fs() removal.
This series adds read_iter support for seq_file, and uses those for
various proc files using seq_file to restore splice read support"
[ Side note: Christoph initially had a scripted "move everything over"
patch, which looks fine, but I personally would prefer us to actively
discourage splice() on random files. So this does just the minimal
basic core set of proc file op conversions.
For completeness, and in case people care, that script was
sed -i -e 's/\.proc_read\(\s*=\s*\)seq_read/\.proc_read_iter\1seq_read_iter/g'
but I'll wait and see if somebody has a strong argument for using
splice on random small /proc files before I'd run it on the whole
kernel. - Linus ]
* emailed patches from Christoph Hellwig <hch@lst.de>:
proc "seq files": switch to ->read_iter
proc "single files": switch to ->read_iter
proc/stat: switch to ->read_iter
proc/cpuinfo: switch to ->read_iter
proc: wire up generic_file_splice_read for iter ops
seq_file: add seq_read_iter
Pull x86 fixes from Thomas Gleixner:
"A set of x86 fixes:
- Use SYM_FUNC_START_WEAK in the mem* ASM functions instead of a
combination of .weak and SYM_FUNC_START_LOCAL which makes LLVMs
integrated assembler upset
- Correct the mitigation selection logic which prevented the related
prctl to work correctly
- Make the UV5 hubless system work correctly by fixing up the
malformed table entries and adding the missing ones"
* tag 'x86-urgent-2020-11-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/platform/uv: Recognize UV5 hubless system identifier
x86/platform/uv: Remove spaces from OEM IDs
x86/platform/uv: Fix missing OEM_TABLE_ID
x86/speculation: Allow IBPB to be conditionally enabled on CPUs with always-on STIBP
x86/lib: Change .weak to SYM_FUNC_START_WEAK for arch/x86/lib/mem*_64.S
Pull perf fix from Thomas Gleixner:
"A single fix for the perf core plugging a memory leak in the address
filter parser"
* tag 'perf-urgent-2020-11-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Fix a memory leak in perf_event_parse_addr_filter()
Pull futex fix from Thomas Gleixner:
"A single fix for the futex code where an intermediate state in the
underlying RT mutex was not handled correctly and triggering a BUG()
instead of treating it as another variant of retry condition"
* tag 'locking-urgent-2020-11-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
futex: Handle transient "ownerless" rtmutex state correctly
Pull irq fixes from Thomas Gleixner:
"A set of fixes for interrupt chip drivers:
- Fix the fallout of the IPI as interrupt conversion in Kconfig and
the BCM2836 interrupt chip driver
- Fixes for interrupt affinity setting and the handling of
hierarchical irq domains in the SiFive PLIC driver
- Make the unmapped event handling in the TI SCI driver work
correctly
- A few minor fixes and cleanups in various chip drivers and Kconfig"
* tag 'irq-urgent-2020-11-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
dt-bindings: irqchip: ti, sci-inta: Fix diagram indentation for unmapped events
irqchip/ti-sci-inta: Add support for unmapped event handling
dt-bindings: irqchip: ti, sci-inta: Update for unmapped event handling
irqchip/renesas-intc-irqpin: Merge irlm_bit and needs_irlm
irqchip/sifive-plic: Fix chip_data access within a hierarchy
irqchip/sifive-plic: Fix broken irq_set_affinity() callback
irqchip/stm32-exti: Add all LP timer exti direct events support
irqchip/bcm2836: Fix missing __init annotation
irqchip/mips: Drop selection of IRQ_DOMAIN_HIERARCHY
irqchip/mst: Make mst_intc_of_init static
irqchip/mst: MST_IRQ should depend on ARCH_MEDIATEK or ARCH_MSTARV7
genirq: Let GENERIC_IRQ_IPI select IRQ_DOMAIN_HIERARCHY
