When boxes are run near (or to) OOM, we have a problem with the discard
page allocation in sd. If we fail allocating the special page, we return
busy, and it'll get retried. But since ordering is honored for dispatch
requests, we can keep retrying this same IO and failing. Behind that IO
could be requests that want to free memory, but they never get the
chance. This means you get repeated spews of traces like this:
The HP lt4132 is a rebranded Huawei ME906s-158 LTE modem.
The interface with protocol 0x16 is "CDC ECM & NCM" according to the *.inf
files included with the Windows driver. Attaching the option driver to it
doesn't result in a /dev/ttyUSB* device being created, so I've excluded it.
Note that it is also excluded for corresponding Huawei-branded devices, cf.
commit d544db293a44 ("USB: support new huawei devices in option.c").
The code to prevent a bus suspend if a USB3 port was still in link training
also reacted to USB2 port polling state.
This caused bus suspend to busyloop in some cases.
USB2 polling state is different from USB3, and should not prevent bus
suspend.
Limit the USB3 link training state check to USB3 root hub ports only.
The origial commit went to stable so this need to be applied there as well
Fixes: 2f31a67f01a8 ("usb: xhci: Prevent bus suspend if a port connect change or polling state is detected") Cc: stable@vger.kernel.org Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
The function hso_probe reads if_num from the USB device (as an u8) and uses
it without a length check to index an array, resulting in an OOB memory read
in hso_probe or hso_get_config_data.
Add a length check for both locations and updated hso_probe to bail on
error.
This issue has been assigned CVE-2018-19985.
Reported-by: Hui Peng <benquike@gmail.com> Reported-by: Mathias Payer <mathias.payer@nebelwelt.net> Signed-off-by: Hui Peng <benquike@gmail.com> Signed-off-by: Mathias Payer <mathias.payer@nebelwelt.net> Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
The ESD watchdog code in sta32x_watchdog() dereferences the pointer
which is never assigned.
This is a regression from a1be4cead9b950 ("ASoC: sta32x: Convert to direct
regmap API usage.") which went unnoticed since nobody seems to use that ESD
workaround.
Fixes: a1be4cead9b950 ("ASoC: sta32x: Convert to direct regmap API usage.") Signed-off-by: Daniel Mack <daniel@zonque.org> Signed-off-by: Mark Brown <broonie@kernel.org> Cc: stable@vger.kernel.org Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
If __blkdev_issue_discard is in progress and a device mapper device is
reloaded with a table that doesn't support discard,
q->limits.max_discard_sectors is set to zero. This results in infinite
loop in __blkdev_issue_discard.
This patch checks if max_discard_sectors is zero and aborts with
-EOPNOTSUPP.
struct bioctx includes the ref refcount_t to track the number of I/O
fragments used to process a target BIO as well as ensure that the zone
of the BIO is kept in the active state throughout the lifetime of the
BIO. However, since decrementing of this reference count is done in the
target .end_io method, the function bio_endio() must be called multiple
times for read and write target BIOs, which causes problems with the
value of the __bi_remaining struct bio field for chained BIOs (e.g. the
clone BIO passed by dm core is large and splits into fragments by the
block layer), resulting in incorrect values and inconsistencies with the
BIO_CHAIN flag setting. This is turn triggers the BUG_ON() call:
BUG_ON(atomic_read(&bio->__bi_remaining) <= 0);
in bio_remaining_done() called from bio_endio().
Fix this ensuring that bio_endio() is called only once for any target
BIO by always using internal clone BIOs for processing any read or
write target BIO. This allows reference counting using the target BIO
context counter to trigger the target BIO completion bio_endio() call
once all data, metadata and other zone work triggered by the BIO
complete.
Overall, this simplifies the code too as the target .end_io becomes
unnecessary and differences between read and write BIO issuing and
completion processing disappear.
Fixes: 3b1a94c88b79 ("dm zoned: drive-managed zoned block device target") Cc: stable@vger.kernel.org Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Commit 78e5dfea84dc ("powerpc: dts: replace 'linux,stdout-path' with
'stdout-path'") broke the default console on a number of embedded
PowerPC systems, because it failed to also update the code in
arch/powerpc/kernel/legacy_serial.c to look for that property in
addition to the old one.
This fixes it.
Fixes: 78e5dfea84dc ("powerpc: dts: replace 'linux,stdout-path' with 'stdout-path'") Cc: stable@vger.kernel.org # v4.17+ Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Reviewed-by: Rob Herring <robh@kernel.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
vb2_start_streaming() already rolls back the buffers, so there is no
need to call __vb2_queue_cancel(). Especially since __vb2_queue_cancel()
does too much, such as zeroing the q->queued_count value, causing vb2
to think that no buffers have been queued.
It appears that this call to __vb2_queue_cancel() is a left-over from
before commit b3379c6201bb3.
Fixes: b3379c6201bb3 ('vb2: only call start_streaming if sufficient buffers are queued') Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> Cc: <stable@vger.kernel.org> # for v4.16 and up Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com> Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
When sending out CMD23 in the blk preparation, the comment there
rightfully says:
* However, it is not sufficient to just send CMD23,
* and avoid the final CMD12, as on an error condition
* CMD12 (stop) needs to be sent anyway. This, coupled
* with Auto-CMD23 enhancements provided by some
* hosts, means that the complexity of dealing
* with this is best left to the host. If CMD23 is
* supported by card and host, we'll fill sbc in and let
* the host deal with handling it correctly.
Let's do this behaviour for RPMB as well, and not send CMD23
independently. Otherwise IP cores (like Renesas SDHI) may timeout
because of automatic CMD23/CMD12 handling.
BugLink: https://bugs.launchpad.net/bugs/1837257
Upstream commit 972910948fb6 ("ARM: dts: qcom: Remove Arrow SD600
eval board") removed this file because there are no known users,
but in linux-4.19.y, we still get a compile-time warnign for it:
arch/arm/boot/dts/qcom-apq8064-arrow-sd-600eval.dtb: Warning (graph_endpoint): /soc/mdp@5100000/ports/port@3/endpoint: graph connection to node '/soc/hdmi-tx@4a00000/ports/port@0/endpoint' is not bidirectional
Address the warning by adding the remote endpoint that makes the link
bidirectional. This is the same property that other boards use.
drivers/scsi/raid_class.c: In function 'raid_match':
drivers/scsi/raid_class.c:64:24: error: unused variable 'i' [-Werror=unused-variable]
This looks like a very old problem that for some reason was very hard to
run into, but it is very easy to fix, by replacing the incorrect #ifdef
with a simpler IS_ENABLED() check.
Fixes: fac829fdcaf4 ("[SCSI] raid_attrs: fix dependency problems") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Nicolas Schichan [Wed, 19 Dec 2018 21:40:42 +0000 (22:40 +0100)]
bpf, arm: fix emit_ldx_r and emit_mov_i using TMP_REG_1
BugLink: https://bugs.launchpad.net/bugs/1837257
emit_ldx_r() and emit_a32_mov_i() were both using TMP_REG_1 and
clashing with each other. Using TMP_REG_2 in emit_ldx_r() fixes
the issue.
Fixes: ec19e02b343 ("ARM: net: bpf: fix LDX instructions") Cc: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Nicolas Schichan <nschichan@freebox.fr> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
In order to read correctly from asynchronously updated RTC registers,
it's necessary to read repeatedly until their values do not change from
read to read. It's also necessary to wait for three RTC clock ticks for
certain operations. There are no timeouts in this code and these
operations could possibly loop forever.
To avoid kernel hangs, put in timeouts.
The iMX7d can be configured to stop the SRTC on a tamper event, which
will lockup the kernel inside this driver as described above.
These hangs can happen when running under qemu, which doesn't emulate
the SNVS RTC, though currently the driver will refuse to load on qemu
due to a timeout in the driver probe method.
It could also happen if the SRTC block where somehow placed into reset
or the slow speed clock that drives the SRTC counter (but not the CPU)
were to stop.
The symptoms on a two core iMX7d are a work queue hang on
rtc_timer_do_work(), which eventually blocks a systemd fsnotify
operation that triggers a work queue flush, causing systemd to hang and
thus causing all services that should be started by systemd, like a
console getty, to fail to start or stop.
Also optimize the wait code to wait less. It only needs to wait for the
clock to advance three ticks, not to see it change three times.
Some AMD based HP laptops have a SMB0001 ACPI device node which does not
define any methods.
This leads to the following error in dmesg:
[ 5.222731] cmi: probe of SMB0001:00 failed with error -5
This commit makes acpi_smbus_cmi_add() return -ENODEV instead in this case
silencing the error. In case of a failure of the i2c_add_adapter() call
this commit now propagates the error from that call instead of -EIO.
Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
According to Intel (R) Axxia TM Lionfish Communication Processor
Peripheral Subsystem Hardware Reference Manual, the AXXIA I2C module
have a programmable Master Wait Timer, which among others, checks the
time between commands send in manual mode. When a timeout (25ms) passes,
TSS bit is set in Master Interrupt Status register and a Stop command is
issued by the hardware.
The axxia_i2c_xfer(), does not properly handle this situation, however.
For each message a separate axxia_i2c_xfer_msg() is called and this
function incorrectly assumes that any interrupt might happen only when
waiting for completion. This is mostly correct but there is one
exception - a master timeout can trigger if enough time has passed
between individual transfers. It will, by definition, happen between
transfers when the interrupts are disabled by the code. If that happens,
the hardware issues Stop command.
The interrupt indicating timeout will not be triggered as soon as we
enable them since the Master Interrupt Status is cleared when master
mode is entered again (which happens before enabling irqs) meaning this
error is lost and the transfer is continued even though the Stop was
issued on the bus. The subsequent operations completes without error but
a bogus value (0xFF in case of read) is read as the client device is
confused because aborted transfer. No error is returned from
master_xfer() making caller believe that a valid value was read.
To fix the problem, the TSS bit (indicating timeout) in Master Interrupt
Status register is checked before each transfer. If it is set, there was
a timeout before this transfer and (as described above) the hardware
already issued Stop command so the transaction should be aborted thus
-ETIMEOUT is returned from the master_xfer() callback. In order to be
sure no timeout was issued we can't just read the status just before
starting new transaction as there will always be a small window of time
(few CPU cycles at best) where this might still happen. For this reason
we have to temporally disable the timer before checking for TSS bit.
Disabling it will, however, clear the TSS bit so in order to preserve
that information, we have to read it in ISR so we have to ensure that
the TSS interrupt is not masked between transfers of one transaction.
There is no need to call bus recovery or controller reinitialization if
that happens so it's skipped.
Signed-off-by: Krzysztof Adamski <krzysztof.adamski@nokia.com> Reviewed-by: Alexander Sverdlin <alexander.sverdlin@nokia.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
When deleting a VLAN device using an ioctl the netdev is unregistered
before the VLAN filter is updated via ndo_vlan_rx_kill_vid(). It can
lead to a use-after-free in mlxsw in case the VLAN device is deleted
while being enslaved to a bridge.
The reason for the above is that when mlxsw receives the CHANGEUPPER
event, it wrongly assumes that the VLAN device is no longer its upper
and thus destroys the internal representation of the bridge port despite
the reference count being non-zero.
Fix this by checking if the VLAN device is our upper using its real
device. In net-next I'm going to remove this trick and instead make
mlxsw completely agnostic to the order of the events.
Fixes: c57529e1d5d8 ("mlxsw: spectrum: Replace vPorts with Port-VLAN") Signed-off-by: Ido Schimmel <idosch@mellanox.com> Reviewed-by: Petr Machata <petrm@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
If a local process has closed a connected socket and hasn't received a
RST packet yet, then the socket remains in the table until a timeout
expires.
When a vhost_vsock instance is released with the timeout still pending,
the socket is never freed because vhost_vsock has already set the
SOCK_DONE flag.
Check if the close timer is pending and let it close the socket. This
prevents the race which can leak sockets.
Reported-by: Maximilian Riemensberger <riemensberger@cadami.net> Cc: Graham Whaley <graham.whaley@gmail.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
When unloading the ast driver, a warning message is printed by
drm_mode_config_cleanup() because a reference is still held to one of
the drm_connector structs.
Correct this by calling drm_crtc_force_disable_all() in
ast_fbdev_destroy().
After getting a reference to the platform device's of_node the probe
function ends up calling of_find_matching_node() using the node as an
argument. The function takes care of decreasing the refcount on it. We
are then incorrectly decreasing the refcount on that node again.
This patch removes the unwarranted call to of_node_put().
Fixes: 414fd46e7762 ("fsl/fman: Add FMan support") Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Chris has discovered and reported that v7_dma_inv_range() may corrupt
memory if address range is not aligned to cache line size.
Since the whole cache-v7m.S was lifted form cache-v7.S the same
observation applies to v7m_dma_inv_range(). So the fix just mirrors
what has been done for v7 with a little specific of M-class.
Cc: Chris Cole <chris@sageembedded.com> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
This patch addresses possible memory corruption when
v7_dma_inv_range(start_address, end_address) address parameters are not
aligned to whole cache lines. This function issues "invalidate" cache
management operations to all cache lines from start_address (inclusive)
to end_address (exclusive). When start_address and/or end_address are
not aligned, the start and/or end cache lines are first issued "clean &
invalidate" operation. The assumption is this is done to ensure that any
dirty data addresses outside the address range (but part of the first or
last cache lines) are cleaned/flushed so that data is not lost, which
could happen if just an invalidate is issued.
The problem is that these first/last partial cache lines are issued
"clean & invalidate" and then "invalidate". This second "invalidate" is
not required and worse can cause "lost" writes to addresses outside the
address range but part of the cache line. If another component writes to
its part of the cache line between the "clean & invalidate" and
"invalidate" operations, the write can get lost. This fix is to remove
the extra "invalidate" operation when unaligned addressed are used.
A kernel module is available that has a stress test to reproduce the
issue and a unit test of the updated v7_dma_inv_range(). It can be
downloaded from
http://ftp.sageembedded.com/outgoing/linux/cache-test-20181107.tgz.
v7_dma_inv_range() is call by dmac_[un]map_area(addr, len, direction)
when the direction is DMA_FROM_DEVICE. One can (I believe) successfully
argue that DMA from a device to main memory should use buffers aligned
to cache line size, because the "clean & invalidate" might overwrite
data that the device just wrote using DMA. But if a driver does use
unaligned buffers, at least this fix will prevent memory corruption
outside the buffer.
Signed-off-by: Chris Cole <chris@sageembedded.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
MLX4_EN depends on NETDEVICES, ETHERNET and INET Kconfigs.
Make sure they are listed in MLX4_EN Kconfig dependencies.
This fixes the following build break:
drivers/net/ethernet/mellanox/mlx4/en_rx.c:582:18: warning: ‘struct iphdr’ declared inside parameter list [enabled by default]
struct iphdr *iph)
^
drivers/net/ethernet/mellanox/mlx4/en_rx.c:582:18: warning: its scope is only this definition or declaration, which is probably not what you want [enabled by default]
drivers/net/ethernet/mellanox/mlx4/en_rx.c: In function ‘get_fixed_ipv4_csum’:
drivers/net/ethernet/mellanox/mlx4/en_rx.c:586:20: error: dereferencing pointer to incomplete type
_u8 ipproto = iph->protocol;
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com> Signed-off-by: Tariq Toukan <tariqt@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Disable hardware level MAC learning because it breaks station roaming.
When enabled it drops all frames that arrive from a MAC address
that is on a different port at learning table.
Signed-off-by: Anderson Luiz Alves <alacn1@gmail.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
These devices support read zero after trim (RZAT), as they advertise to
the OS. However, the OS doesn't believe the SSDs unless they are
explicitly whitelisted.
Acked-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Juha-Matti Tilli <juha-matti.tilli@iki.fi> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
I noticed that the Android v3.0.8 kernel on droid4 is using different
keypad values from the mainline kernel and does not have issues with
keys occasionally being stuck until pressed again. Turns out there was
an earlier patch posted to fix this as "Input: omap-keypad: errata i689:
Correct debounce time", but it was never reposted to fix use macros
for timing calculations.
This updated version is using macros, and also fixes the use of the
input clock rate to use 32768KiHz instead of 32000KiHz. And we want to
use the known good Android kernel values of 3 and 6 instead of 2 and 6
in the earlier patch.
Reported-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
SMBus works fine for the touchpad with id SYN3221, used in the HP 15-ay000
series,
This device has been reported in these messages in the "linux-input"
mailing list:
* https://marc.info/?l=linux-input&m=152016683003369&w=2
* https://www.spinics.net/lists/linux-input/msg52525.html
These > comparisons should be >= to prevent reading beyond the end of
of the clk_data->hws[] buffer.
The clk_data->hws[] array is allocated in cp110_syscon_common_probe()
when we do:
cp110_clk_data = devm_kzalloc(dev, sizeof(*cp110_clk_data) +
sizeof(struct clk_hw *) * CP110_CLK_NUM,
GFP_KERNEL);
As you can see, it has CP110_CLK_NUM elements which is equivalent to
CP110_MAX_CORE_CLOCKS + CP110_MAX_GATABLE_CLOCKS.
Fixes: d3da3eaef7f4 ("clk: mvebu: new driver for Armada CP110 system controller") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Stephen Boyd <sboyd@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
The error checks on ret for a negative error return always fails because
the return value of iommu_map_sg() is unsigned and can never be negative.
Detected with Coccinelle:
drivers/gpu/drm/msm/msm_iommu.c:69:9-12: WARNING: Unsigned expression
compared with zero: ret < 0
Signed-off-by: Wen Yang <wen.yang99@zte.com.cn> CC: Rob Clark <robdclark@gmail.com> CC: David Airlie <airlied@linux.ie> CC: Julia Lawall <julia.lawall@lip6.fr> CC: linux-arm-msm@vger.kernel.org CC: dri-devel@lists.freedesktop.org CC: freedreno@lists.freedesktop.org CC: linux-kernel@vger.kernel.org Signed-off-by: Sean Paul <seanpaul@chromium.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Signed-off-by: Yangtao Li <tiny.windzz@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
of_find_node_by_path() acquires a reference to the node
returned by it and that reference needs to be dropped by its caller.
This place is not doing this, so fix it.
Signed-off-by: Yangtao Li <tiny.windzz@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Signed-off-by: Yangtao Li <tiny.windzz@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Signed-off-by: Yangtao Li <tiny.windzz@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
If an asynchronous connection attempt completes while another task is
in xprt_connect(), then the call to rpc_sleep_on() could end up
racing with the call to xprt_wake_pending_tasks().
So add a second test of the connection state after we've put the
task to sleep and set the XPRT_CONNECTING flag, when we know that there
can be no asynchronous connection attempts still in progress.
Fixes: 0b9e79431377d ("SUNRPC: Move the test for XPRT_CONNECTING into...") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
When we use direct_IO with an NFS backing store, we can trigger a
WARNING in __set_page_dirty(), as below, since we're dirtying the page
unnecessarily in nfs_direct_read_completion().
To fix, replicate the logic in commit 53cbf3b157a0 ("fs: direct-io:
don't dirtying pages for ITER_BVEC/ITER_KVEC direct read").
Other filesystems that implement direct_IO handle this; most use
blockdev_direct_IO(). ceph and cifs have similar logic.
mount 127.0.0.1:/export /nfs
dd if=/dev/zero of=/nfs/image bs=1M count=200
losetup --direct-io=on -f /nfs/image
mkfs.btrfs /dev/loop0
mount -t btrfs /dev/loop0 /mnt/
Previously when unbinding a slave the 802.3ad implementation only told
partner that the port is not suitable for aggregation by setting the port
aggregation state from aggregatable to individual. This is not enough. If the
physical layer still stays up and we only unbinded this port from the bond there
is nothing in the aggregation status alone to prevent the partner from sending
traffic towards us. To ensure that the partner doesn't consider this
port at all anymore we should also disable collecting and distributing to
signal that this actor is going away. Also clear AD_STATE_SYNCHRONIZATION to
ensure partner exits collecting + distributing state.
I have tested this behaviour againts Arista EOS switches with mlx5 cards
(physical link stays up even when interface is down) and simulated
the same situation virtually Linux <-> Linux with two network namespaces
running two veth device pairs. In both cases setting aggregation to
individual doesn't alone prevent traffic from being to sent towards this
port given that the link stays up in partners end. Partner still keeps
it's end in collecting + distributing state and continues until timeout is
reached. In most cases this means we are losing the traffic partner sends
towards our port while we wait for timeout. This is most visible with slow
periodic time (LACP rate slow).
Other open source implementations like Open VSwitch and libreswitch, and
vendor implementations like Arista EOS, seem to disable collecting +
distributing to when doing similar port disabling/detaching/removing change.
With this patch kernel implementation would behave the same way and ensure
partner doesn't consider our actor viable anymore.
Signed-off-by: Toni Peltonen <peltzi@peltzi.fi> Signed-off-by: Jay Vosburgh <jay.vosburgh@canonical.com> Acked-by: Jonathan Toppins <jtoppins@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Some ARC CPU's do not support unaligned loads/stores. Currently, generic
implementation of reads{b/w/l}()/writes{b/w/l}() is being used with ARC.
This can lead to misfunction of some drivers as generic functions do a
plain dereference of a pointer that can be unaligned.
Let's use {get/put}_unaligned() helpers instead of plain dereference of
pointer in order to fix. The helpers allow to get and store data from an
unaligned address whilst preserving the CPU internal alignment.
According to [1], the use of these helpers are costly in terms of
performance so we added an initial check for a buffer already aligned so
that the usage of the helpers can be avoided, when possible.
Similar to the atomic helpers, we should enable vblank while we're
waiting for the commit to finish. DPU needs this, MDP5 seems to work
fine without it.
Reviewed-by: Abhinav Kumar <abhinavk@codeaurora.org> Signed-off-by: Sean Paul <seanpaul@chromium.org> Signed-off-by: Rob Clark <robdclark@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
An affected screen resolution is 1366 x 768, which width is not
divisible by 8, the default font width. On such screens, when longer
lines are earlyprintk'ed, overflow-to-next-line can never trigger,
due to the left-most x-coordinate of the next character always less
than the screen width. Earlyprintk will infinite loop in trying to
print the rest of the string but unable to, due to the line being
full.
This patch makes the trigger consider the right-most x-coordinate,
instead of left-most, as the value to compare against the screen
width threshold.
Signed-off-by: YiFei Zhu <zhuyifei1999@gmail.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arend van Spriel <arend.vanspriel@broadcom.com> Cc: Bhupesh Sharma <bhsharma@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Eric Snowberg <eric.snowberg@oracle.com> Cc: Hans de Goede <hdegoede@redhat.com> Cc: Joe Perches <joe@perches.com> Cc: Jon Hunter <jonathanh@nvidia.com> Cc: Julien Thierry <julien.thierry@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Nathan Chancellor <natechancellor@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com> Cc: Sedat Dilek <sedat.dilek@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/20181129171230.18699-12-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Currently pvscsi_remove calls free_irq more than once as
pvscsi_release_resources and __pvscsi_shutdown both call
pvscsi_shutdown_intr. This results in a 'Trying to free already-free IRQ'
warning and stack trace. To solve the problem pvscsi_shutdown_intr has been
moved out of pvscsi_release_resources.
Signed-off-by: Cathy Avery <cavery@redhat.com> Reviewed-by: Ewan D. Milne <emilne@redhat.com> Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
This commit addresses NULL pointer dereference in iscsi_eh_session_reset.
Reference should not be made to session->leadconn when session->state is
set to ISCSI_STATE_TERMINATE.
Signed-off-by: Fred Herard <fred.herard@oracle.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Lee Duncan <lduncan@suse.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
It makes little sense but still possible to put Hyper-V guests into
suspend-to-idle state. To wake them up two wakeup sources were registered
in the past: hyperv-keyboard and hid-hyperv. However, since
commit eed4d47efe95 ("ACPI / sleep: Ignore spurious SCI wakeups from
suspend-to-idle") pm_wakeup_event() from these devices is ignored. Switch
to pm_wakeup_hard_event() API as these devices are actually the only
possible way to wakeup Hyper-V guests.
Fixes: eed4d47efe95 (ACPI / sleep: Ignore spurious SCI wakeups from suspend-to-idle) Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: K. Y. Srinivasan <kys@microsoft.com> Acked-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
There is no unregister netlink notifier and family on error paths
in init_mac80211_hwsim(). Also there is an error path where
hwsim_class is not destroyed.
Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru> Fixes: 62759361eb49 ("mac80211-hwsim: Provide multicast event for HWSIM_CMD_NEW_RADIO") Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
One of my tests compiles the kernel with gcc 4.5.3, and I hit the
following build error:
include/linux/semaphore.h: In function 'sema_init':
include/linux/semaphore.h:35:17: error: unknown field 'val' specified in initializer
include/linux/semaphore.h:35:17: warning: missing braces around initializer
include/linux/semaphore.h:35:17: warning: (near initialization for '(anonymous).raw_lock.<anonymous>.val')
I bisected it down to:
625e88be1f41 ("locking/qspinlock: Merge 'struct __qspinlock' into 'struct qspinlock'")
... which makes qspinlock have an anonymous union, which makes initializing it special
for older compilers. By adding strategic brackets, it makes the build
happy again.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Acked-by: Waiman Long <longman@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-arm-kernel@lists.infradead.org Fixes: 625e88be1f41 ("locking/qspinlock: Merge 'struct __qspinlock' into 'struct qspinlock'") Link: http://lkml.kernel.org/r/20180621203526.172ab5c4@vmware.local.home Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Packet queue state is over used to determine SDMA descriptor
availablitity and packet queue request state.
cpu 0 ret = user_sdma_send_pkts(req, pcount);
cpu 0 if (atomic_read(&pq->n_reqs))
cpu 1 IRQ user_sdma_txreq_cb calls pq_update() (state to _INACTIVE)
cpu 0 xchg(&pq->state, SDMA_PKT_Q_ACTIVE);
At this point pq->n_reqs == 0 and pq->state is incorrectly
SDMA_PKT_Q_ACTIVE. The close path will hang waiting for the state
to return to _INACTIVE.
This can also change the state from _DEFERRED to _ACTIVE. However,
this is a mostly benign race.
Remove the racy code path.
Use n_reqs to determine if a packet queue is active or not.
Cc: <stable@vger.kernel.org> # 4.14.0> Reviewed-by: Mitko Haralanov <mitko.haralanov@intel.com> Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com> Signed-off-by: Michael J. Ruhl <michael.j.ruhl@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Commit c470bdc1aaf3 ("mac80211: don't WARN on bad WMM parameters from
buggy APs") handled cases where an AP reports a zeroed WMM
IE. However, the condition that checks the validity accessed the wrong
index in the ieee80211_tx_queue_params array, thus wrongly deducing
that the parameters are invalid. Fix it.
Fixes: c470bdc1aaf3 ("mac80211: don't WARN on bad WMM parameters from buggy APs") Signed-off-by: Ilan Peer <ilan.peer@intel.com> Signed-off-by: Luca Coelho <luciano.coelho@intel.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Apparently, some APs are buggy enough to send a zeroed
WMM IE. Don't WARN on this since this is not caused by a bug
on the client's system.
This aligns the condition of the WARNING in drv_conf_tx
with the validity check in ieee80211_sta_wmm_params.
We will now pick the default values whenever we get
a zeroed WMM IE.
This has been reported here:
https://bugzilla.kernel.org/show_bug.cgi?id=199161
Fixes: f409079bb678 ("mac80211: sanity check CW_min/CW_max towards driver") Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
On x86 we cannot do fetch_or() with a single instruction and thus end up
using a cmpxchg loop, this reduces determinism. Replace the fetch_or()
with a composite operation: tas-pending + load.
Using two instructions of course opens a window we previously did not
have. Consider the scenario:
CPU0 CPU1 CPU2
1) lock
trylock -> (0,0,1)
2) lock
trylock /* fail */
3) unlock -> (0,0,0)
4) lock
trylock -> (0,0,1)
5) tas-pending -> (0,1,1)
load-val <- (0,1,0) from 3
6) clear-pending-set-locked -> (0,0,1)
FAIL: _2_ owners
where 5) is our new composite operation. When we consider each part of
the qspinlock state as a separate variable (as we can when
_Q_PENDING_BITS == 8) then the above is entirely possible, because
tas-pending will only RmW the pending byte, so the later load is able
to observe prior tail and lock state (but not earlier than its own
trylock, which operates on the whole word, due to coherence).
To avoid this we need 2 things:
- the load must come after the tas-pending (obviously, otherwise it
can trivially observe prior state).
- the tas-pending must be a full word RmW instruction, it cannot be an XCHGB for
example, such that we cannot observe other state prior to setting
pending.
On x86 we can realize this by using "LOCK BTS m32, r32" for
tas-pending followed by a regular load.
Note that observing later state is not a problem:
- if we fail to observe a later unlock, we'll simply spin-wait for
that store to become visible.
- if we observe a later xchg_tail(), there is no difference from that
xchg_tail() having taken place before the tas-pending.
Suggested-by: Will Deacon <will.deacon@arm.com> Reported-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Will Deacon <will.deacon@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: andrea.parri@amarulasolutions.com Cc: longman@redhat.com Fixes: 59fb586b4a07 ("locking/qspinlock: Remove unbounded cmpxchg() loop from locking slowpath") Link: https://lkml.kernel.org/r/20181003130957.183726335@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
[bigeasy: GEN_BINARY_RMWcc macro redo] Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
On x86, atomic_cond_read_relaxed will busy-wait with a cpu_relax() loop,
so it is desirable to increase the number of times we spin on the qspinlock
lockword when it is found to be transitioning from pending to locked.
According to Waiman Long:
| Ideally, the spinning times should be at least a few times the typical
| cacheline load time from memory which I think can be down to 100ns or
| so for each cacheline load with the newest systems or up to several
| hundreds ns for older systems.
which in his benchmarking corresponded to 512 iterations.
Suggested-by: Waiman Long <longman@redhat.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Waiman Long <longman@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: boqun.feng@gmail.com Cc: linux-arm-kernel@lists.infradead.org Cc: paulmck@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/1524738868-31318-5-git-send-email-will.deacon@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Flip the branch condition after atomic_fetch_or_acquire(_Q_PENDING_VAL)
such that we loose the indent. This also result in a more natural code
flow IMO.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Will Deacon <will.deacon@arm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: andrea.parri@amarulasolutions.com Cc: longman@redhat.com Link: https://lkml.kernel.org/r/20181003130257.156322446@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
When a queued locker reaches the head of the queue, it claims the lock
by setting _Q_LOCKED_VAL in the lockword. If there isn't contention, it
must also clear the tail as part of this operation so that subsequent
lockers can avoid taking the slowpath altogether.
Currently this is expressed as a cmpxchg() loop that practically only
runs up to two iterations. This is confusing to the reader and unhelpful
to the compiler. Rewrite the cmpxchg() loop without the loop, so that a
failed cmpxchg() implies that there is contention and we just need to
write to _Q_LOCKED_VAL without considering the rest of the lockword.
Signed-off-by: Will Deacon <will.deacon@arm.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Waiman Long <longman@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: boqun.feng@gmail.com Cc: linux-arm-kernel@lists.infradead.org Cc: paulmck@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/1524738868-31318-7-git-send-email-will.deacon@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
The qspinlock locking slowpath utilises a "pending" bit as a simple form
of an embedded test-and-set lock that can avoid the overhead of explicit
queuing in cases where the lock is held but uncontended. This bit is
managed using a cmpxchg() loop which tries to transition the uncontended
lock word from (0,0,0) -> (0,0,1) or (0,0,1) -> (0,1,1).
Unfortunately, the cmpxchg() loop is unbounded and lockers can be starved
indefinitely if the lock word is seen to oscillate between unlocked
(0,0,0) and locked (0,0,1). This could happen if concurrent lockers are
able to take the lock in the cmpxchg() loop without queuing and pass it
around amongst themselves.
This patch fixes the problem by unconditionally setting _Q_PENDING_VAL
using atomic_fetch_or, and then inspecting the old value to see whether
we need to spin on the current lock owner, or whether we now effectively
hold the lock. The tricky scenario is when concurrent lockers end up
queuing on the lock and the lock becomes available, causing us to see
a lockword of (n,0,0). With pending now set, simply queuing could lead
to deadlock as the head of the queue may not have observed the pending
flag being cleared. Conversely, if the head of the queue did observe
pending being cleared, then it could transition the lock from (n,0,0) ->
(0,0,1) meaning that any attempt to "undo" our setting of the pending
bit could race with a concurrent locker trying to set it.
We handle this race by preserving the pending bit when taking the lock
after reaching the head of the queue and leaving the tail entry intact
if we saw pending set, because we know that the tail is going to be
updated shortly.
Signed-off-by: Will Deacon <will.deacon@arm.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Waiman Long <longman@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: boqun.feng@gmail.com Cc: linux-arm-kernel@lists.infradead.org Cc: paulmck@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/1524738868-31318-6-git-send-email-will.deacon@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
'struct __qspinlock' provides a handy union of fields so that
subcomponents of the lockword can be accessed by name, without having to
manage shifts and masks explicitly and take endianness into account.
This is useful in qspinlock.h and also potentially in arch headers, so
move the 'struct __qspinlock' into 'struct qspinlock' and kill the extra
definition.
Signed-off-by: Will Deacon <will.deacon@arm.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Waiman Long <longman@redhat.com> Acked-by: Boqun Feng <boqun.feng@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arm-kernel@lists.infradead.org Cc: paulmck@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/1524738868-31318-3-git-send-email-will.deacon@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
If a locker taking the qspinlock slowpath reads a lock value indicating
that only the pending bit is set, then it will spin whilst the
concurrent pending->locked transition takes effect.
Unfortunately, there is no guarantee that such a transition will ever be
observed since concurrent lockers could continuously set pending and
hand over the lock amongst themselves, leading to starvation. Whilst
this would probably resolve in practice, it means that it is not
possible to prove liveness properties about the lock and means that lock
acquisition time is unbounded.
Rather than removing the pending->locked spinning from the slowpath
altogether (which has been shown to heavily penalise a 2-threaded
locking stress test on x86), this patch replaces the explicit spinning
with a call to atomic_cond_read_relaxed and allows the architecture to
provide a bound on the number of spins. For architectures that can
respond to changes in cacheline state in their smp_cond_load implementation,
it should be sufficient to use the default bound of 1.
Suggested-by: Waiman Long <longman@redhat.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Waiman Long <longman@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: boqun.feng@gmail.com Cc: linux-arm-kernel@lists.infradead.org Cc: paulmck@linux.vnet.ibm.com Link: http://lkml.kernel.org/r/1524738868-31318-4-git-send-email-will.deacon@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
When a locker ends up queuing on the qspinlock locking slowpath, we
initialise the relevant mcs node and publish it indirectly by updating
the tail portion of the lock word using xchg_tail. If we find that there
was a pre-existing locker in the queue, we subsequently update their
->next field to point at our node so that we are notified when it's our
turn to take the lock.
This can be roughly illustrated as follows:
/* Initialise the fields in node and encode a pointer to node in tail */
tail = initialise_node(node);
/*
* Exchange tail into the lockword using an atomic read-modify-write
* operation with release semantics
*/
old = xchg_tail(lock, tail);
/* If there was a pre-existing waiter ... */
if (old & _Q_TAIL_MASK) {
prev = decode_tail(old);
smp_read_barrier_depends();
/* ... then update their ->next field to point to node.
WRITE_ONCE(prev->next, node);
}
The conditional update of prev->next therefore relies on the address
dependency from the result of xchg_tail ensuring order against the
prior initialisation of node. However, since the release semantics of
the xchg_tail operation apply only to the write portion of the RmW,
then this ordering is not guaranteed and it is possible for the CPU
to return old before the writes to node have been published, consequently
allowing us to point prev->next to an uninitialised node.
This patch fixes the problem by making the update of prev->next a RELEASE
operation, which also removes the reliance on dependency ordering.
Signed-off-by: Will Deacon <will.deacon@arm.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1518528177-19169-2-git-send-email-will.deacon@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Queued spinlocks are not used by DEC Alpha, and furthermore operations
such as READ_ONCE() and release/relaxed RMW atomics are being changed
to imply smp_read_barrier_depends(). This commit therefore removes the
now-redundant smp_read_barrier_depends() from queued_spin_lock_slowpath(),
and adjusts the comments accordingly.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
It is troublesome to add a diagnostic like this to the Makefile
parse stage because the top-level Makefile could be parsed with
a stale include/config/auto.conf.
Once you are hit by the error about non-retpoline compiler, the
compilation still breaks even after disabling CONFIG_RETPOLINE.
The easiest fix is to move this check to the "archprepare" like
this commit did:
829fe4aa9ac1 ("x86: Allow generating user-space headers without a compiler")
Reported-by: Meelis Roos <mroos@linux.ee> Tested-by: Meelis Roos <mroos@linux.ee> Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Acked-by: Zhenzhong Duan <zhenzhong.duan@oracle.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Zhenzhong Duan <zhenzhong.duan@oracle.com> Fixes: 4cd24de3a098 ("x86/retpoline: Make CONFIG_RETPOLINE depend on compiler support") Link: http://lkml.kernel.org/r/1543991239-18476-1-git-send-email-yamada.masahiro@socionext.com Link: https://lkml.org/lkml/2018/12/4/206 Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> Cc: Gi-Oh Kim <gi-oh.kim@cloud.ionos.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Braswell is really picky about having our writes posted to memory before
we execute or else the GPU may see stale values. A wmb() is insufficient
as it only ensures the writes are visible to other cores, we need a full
mb() to ensure the writes are in memory and visible to the GPU.
The most frequent failure in flushing before execution is that we see
stale PTE values and execute the wrong pages.
References: 987abd5c62f9 ("drm/i915/execlists: Force write serialisation into context image vs execution") Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: stable@vger.kernel.org Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20181206084431.9805-3-chris@chris-wilson.co.uk
(cherry picked from commit 490b8c65b9db45896769e1095e78725775f47b3e) Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Noticed this while working on redoing the reference counting scheme in
the DP MST helpers. Nouveau doesn't attempt to call
drm_dp_mst_topology_mgr_destroy() at all, which leaves it leaking all of
the resources for drm_dp_mst_topology_mgr and it's children mstbs+ports.
Fixes: f479c0ba4a17 ("drm/nouveau/kms/nv50: initial support for DP 1.2 multi-stream") Signed-off-by: Lyude Paul <lyude@redhat.com> Cc: <stable@vger.kernel.org> # v4.10+ Signed-off-by: Ben Skeggs <bskeggs@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
The arch_teardown_msi_irqs() function assumes that controller ops
pointers were already checked in arch_setup_msi_irqs(), but this
assumption is wrong: arch_teardown_msi_irqs() can be called even when
arch_setup_msi_irqs() returns an error (-ENOSYS).
This can happen in the following scenario:
- msi_capability_init() calls pci_msi_setup_msi_irqs()
- pci_msi_setup_msi_irqs() returns -ENOSYS
- msi_capability_init() notices the error and calls free_msi_irqs()
- free_msi_irqs() calls pci_msi_teardown_msi_irqs()
This is easier to see when CONFIG_PCI_MSI_IRQ_DOMAIN is not set and
pci_msi_setup_msi_irqs() and pci_msi_teardown_msi_irqs() are just
aliases to arch_setup_msi_irqs() and arch_teardown_msi_irqs().
The call to free_msi_irqs() upon pci_msi_setup_msi_irqs() failure
seems legit, as it does additional cleanup; e.g.
list_del(&entry->list) and kfree(entry) inside free_msi_irqs() do
happen (MSI descriptors are allocated before pci_msi_setup_msi_irqs()
is called and need to be cleaned up if that fails).
Fixes: 6b2fd7efeb88 ("PCI/MSI/PPC: Remove arch_msi_check_device()") Cc: stable@vger.kernel.org # v3.18+ Signed-off-by: Radu Rendec <radu.rendec@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
The reason is that the hashes that hold the filters to set_ftrace_filter and
set_ftrace_notrace are not freed if they contain any data on the instance
and the instance is removed.
Found by kmemleak detector.
Cc: stable@vger.kernel.org Fixes: 591dffdade9f ("ftrace: Allow for function tracing instance to filter functions") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
When create_event_filter() fails in set_trigger_filter(), the filter may
still be allocated and needs to be freed. The caller expects the
data->filter to be updated with the new filter, even if the new filter
failed (we could add an error message by setting set_str parameter of
create_event_filter(), but that's another update).
But because the error would just exit, filter was left hanging and
nothing could free it.
Found by kmemleak detector.
Cc: stable@vger.kernel.org Fixes: bac5fb97a173a ("tracing: Add and use generic set_trigger_filter() implementation") Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Sending a DM event before a thin-pool state change is about to happen is
a bug. It wasn't realized until it became clear that userspace response
to the event raced with the actual state change that the event was
meant to notify about.
Fix this by first updating internal thin-pool state to reflect what the
DM event is being issued about. This fixes a long-standing racey/buggy
userspace device-mapper-test-suite 'resize_io' test that would get an
event but not find the state it was looking for -- so it would just go
on to hang because no other events caused the test to reevaluate the
thin-pool's state.
Cc: stable@vger.kernel.org Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
cpu_is_mmp2() was equivalent to cpu_is_pj4(), wouldn't be correct for
multiplatform kernels. Fix it by also considering mmp_chip_id, as is
done for cpu_is_pxa168() and cpu_is_pxa910() above.
Moreover, it is only available with CONFIG_CPU_MMP2 and thus doesn't work
on DT-based MMP2 machines. Enable it on CONFIG_MACH_MMP2_DT too.
Note: CONFIG_CPU_MMP2 is only used for machines that use board files
instead of DT. It should perhaps be renamed. I'm not doing it now, because
I don't have a better idea.
After checking the sdhci code, we found the timeout check actually has a
little window that the CPU can be scheduled out and when it comes back,
the original time set or check is not valid.
Since v2.6.22 or so there has been reports [1] about OMAP MMC being
broken on OMAP15XX based hardware (OMAP5910 and OMAP310). The breakage
seems to have been caused by commit 46a6730e3ff9 ("mmc-omap: Fix
omap to use MMC_POWER_ON") that changed clock enabling to be done
on MMC_POWER_ON. This can happen multiple times in a row, and on 15XX
the hardware doesn't seem to like it and the MMC just stops responding.
Fix by memorizing the power mode and do the init only when necessary.
We need to invalidate the caches *before* clearing the buffer via the
non-cacheable alias, else in the worst case __dma_flush_area() may
write back dirty lines over the top of our nice new zeros.
Fixes: dd65a941f6ba ("arm64: dma-mapping: clear buffers allocated with FORCE_CONTIGUOUS flag") Cc: <stable@vger.kernel.org> # 4.18.x- Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Calling UFFDIO_UNREGISTER on virtual ranges not yet registered in uffd
could trigger an harmless false positive WARN_ON. Check the vma is
already registered before checking VM_MAYWRITE to shut off the false
positive warning.
Link: http://lkml.kernel.org/r/20181206212028.18726-2-aarcange@redhat.com Cc: <stable@vger.kernel.org> Fixes: 29ec90660d68 ("userfaultfd: shmem/hugetlbfs: only allow to register VM_MAYWRITE vmas") Signed-off-by: Andrea Arcangeli <aarcange@redhat.com> Reported-by: syzbot+06c7092e7d71218a2c16@syzkaller.appspotmail.com Acked-by: Mike Rapoport <rppt@linux.ibm.com> Acked-by: Hugh Dickins <hughd@google.com> Acked-by: Peter Xu <peterx@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Hui Wang [Fri, 26 Jul 2019 03:54:54 +0000 (11:54 +0800)]
UBUNTU: SAUCE: ALSA: hda - Add a conexant codec entry to let mute led work
BugLink: https://bugs.launchpad.net/bugs/1837963
This conexant codec isn't in the supported codec list yet, the hda
generic driver can drive this codec well, but on a Lenovo machine
with mute/mic-mute leds, we need to apply CXT_FIXUP_THINKPAD_ACPI
to make the leds work. After adding this codec to the list, the
driver patch_conexant.c will apply THINKPAD_ACPI to this machine.
Cc: stable@vger.kernel.org Signed-off-by: Hui Wang <hui.wang@canonical.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
(cherry picked from commit 3f8809499bf02ef7874254c5e23fc764a47a21a0
git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound.git) Signed-off-by: Hui Wang <hui.wang@canonical.com> Acked-by: Seth Forshee <seth.forshee@canonical.com> Acked-by: Kai Heng Feng <kai.heng.feng@canonical.com> Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
This upstream commit depends on the following commits: e950564b97fd ("vfs: don't evict uninitialized inode") 80ea09a002bf ("vfs: factor out inode_insert5()")
With this commit only,
Crash happens during the setup (dpkg) phase of sbuild using a overlayfs
based chroot with the current bionic-proposed kernel (4.15.0-56-generic
Thomas Gleixner [Wed, 17 Jul 2019 19:18:59 +0000 (21:18 +0200)]
x86/speculation/swapgs: Exclude ATOMs from speculation through SWAPGS
Intel provided the following information:
On all current Atom processors, instructions that use a segment register
value (e.g. a load or store) will not speculatively execute before the
last writer of that segment retires. Thus they will not use a
speculatively written segment value.
That means on ATOMs there is no speculation through SWAPGS, so the SWAPGS
entry paths can be excluded from the extra LFENCE if PTI is disabled.
Create a separate bug flag for the through SWAPGS speculation and mark all
out-of-order ATOMs and AMD/HYGON CPUs as not affected. The in-order ATOMs
are excluded from the whole mitigation mess anyway.
Reported-by: Andrew Cooper <andrew.cooper3@citrix.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Tyler Hicks <tyhicks@canonical.com> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
CVE-2019-1125
(backported from commit f36cf386e3fec258a341d446915862eded3e13d8)
[tyhicks: Dropped VULNWL_HYGON() change since this kernel version
doesn't know about Hygon processors] Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Somehow the swapgs mitigation entry code patch ended up with a JMPQ
instruction instead of JMP, where only the short jump is needed. Some
assembler versions apparently fail to optimize JMPQ into a two-byte JMP
when possible, instead always using a 7-byte JMP with relocation. For
some reason that makes the entry code explode with a #GP during boot.
Change it back to "JMP" as originally intended.
Fixes: 18ec54fdd6d1 ("x86/speculation: Prepare entry code for Spectre v1 swapgs mitigations") Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
CVE-2019-1125
(backported from commit 64dbc122b20f75183d8822618c24f85144a5a94d)
[tyhicks: Adjust context in entry_64.S] Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
The previous commit added macro calls in the entry code which mitigate the
Spectre v1 swapgs issue if the X86_FEATURE_FENCE_SWAPGS_* features are
enabled. Enable those features where applicable.
The mitigations may be disabled with "nospectre_v1" or "mitigations=off".
There are different features which can affect the risk of attack:
- When FSGSBASE is enabled, unprivileged users are able to place any
value in GS, using the wrgsbase instruction. This means they can
write a GS value which points to any value in kernel space, which can
be useful with the following gadget in an interrupt/exception/NMI
handler:
if (coming from user space)
swapgs
mov %gs:<percpu_offset>, %reg1
// dependent load or store based on the value of %reg
// for example: mov %(reg1), %reg2
If an interrupt is coming from user space, and the entry code
speculatively skips the swapgs (due to user branch mistraining), it
may speculatively execute the GS-based load and a subsequent dependent
load or store, exposing the kernel data to an L1 side channel leak.
Note that, on Intel, a similar attack exists in the above gadget when
coming from kernel space, if the swapgs gets speculatively executed to
switch back to the user GS. On AMD, this variant isn't possible
because swapgs is serializing with respect to future GS-based
accesses.
NOTE: The FSGSBASE patch set hasn't been merged yet, so the above case
doesn't exist quite yet.
- When FSGSBASE is disabled, the issue is mitigated somewhat because
unprivileged users must use prctl(ARCH_SET_GS) to set GS, which
restricts GS values to user space addresses only. That means the
gadget would need an additional step, since the target kernel address
needs to be read from user space first. Something like:
if (coming from user space)
swapgs
mov %gs:<percpu_offset>, %reg1
mov (%reg1), %reg2
// dependent load or store based on the value of %reg2
// for example: mov %(reg2), %reg3
It's difficult to audit for this gadget in all the handlers, so while
there are no known instances of it, it's entirely possible that it
exists somewhere (or could be introduced in the future). Without
tooling to analyze all such code paths, consider it vulnerable.
Effects of SMAP on the !FSGSBASE case:
- If SMAP is enabled, and the CPU reports RDCL_NO (i.e., not
susceptible to Meltdown), the kernel is prevented from speculatively
reading user space memory, even L1 cached values. This effectively
disables the !FSGSBASE attack vector.
- If SMAP is enabled, but the CPU *is* susceptible to Meltdown, SMAP
still prevents the kernel from speculatively reading user space
memory. But it does *not* prevent the kernel from reading the
user value from L1, if it has already been cached. This is probably
only a small hurdle for an attacker to overcome.
Thanks to Dave Hansen for contributing the speculative_smap() function.
Thanks to Andrew Cooper for providing the inside scoop on whether swapgs
is serializing on AMD.
[ tglx: Fixed the USER fence decision and polished the comment as suggested
by Dave Hansen ]
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Dave Hansen <dave.hansen@intel.com>
CVE-2019-1125
(backported from commit a2059825986a1c8143fd6698774fa9d83733bb11)
[tyhicks: Adjust context in kernel-parameters.txt and bugs.c] Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
x86/speculation: Prepare entry code for Spectre v1 swapgs mitigations
Spectre v1 isn't only about array bounds checks. It can affect any
conditional checks. The kernel entry code interrupt, exception, and NMI
handlers all have conditional swapgs checks. Those may be problematic in
the context of Spectre v1, as kernel code can speculatively run with a user
GS.
For example:
if (coming from user space)
swapgs
mov %gs:<percpu_offset>, %reg
mov (%reg), %reg1
When coming from user space, the CPU can speculatively skip the swapgs, and
then do a speculative percpu load using the user GS value. So the user can
speculatively force a read of any kernel value. If a gadget exists which
uses the percpu value as an address in another load/store, then the
contents of the kernel value may become visible via an L1 side channel
attack.
A similar attack exists when coming from kernel space. The CPU can
speculatively do the swapgs, causing the user GS to get used for the rest
of the speculative window.
The mitigation is similar to a traditional Spectre v1 mitigation, except:
a) index masking isn't possible; because the index (percpu offset)
isn't user-controlled; and
b) an lfence is needed in both the "from user" swapgs path and the
"from kernel" non-swapgs path (because of the two attacks described
above).
The user entry swapgs paths already have SWITCH_TO_KERNEL_CR3, which has a
CR3 write when PTI is enabled. Since CR3 writes are serializing, the
lfences can be skipped in those cases.
On the other hand, the kernel entry swapgs paths don't depend on PTI.
To avoid unnecessary lfences for the user entry case, create two separate
features for alternative patching:
Fenghua Yu [Wed, 19 Jun 2019 16:51:09 +0000 (18:51 +0200)]
x86/cpufeatures: Combine word 11 and 12 into a new scattered features word
It's a waste for the four X86_FEATURE_CQM_* feature bits to occupy two
whole feature bits words. To better utilize feature words, re-define
word 11 to host scattered features and move the four X86_FEATURE_CQM_*
features into Linux defined word 11. More scattered features can be
added in word 11 in the future.
Rename leaf 11 in cpuid_leafs to CPUID_LNX_4 to reflect it's a
Linux-defined leaf.
Rename leaf 12 as CPUID_DUMMY which will be replaced by a meaningful
name in the next patch when CPUID.7.1:EAX occupies world 12.
Maximum number of RMID and cache occupancy scale are retrieved from
CPUID.0xf.1 after scattered CQM features are enumerated. Carve out the
code into a separate function.
KVM doesn't support resctrl now. So it's safe to move the
X86_FEATURE_CQM_* features to scattered features word 11 for KVM.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Aaron Lewis <aaronlewis@google.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Babu Moger <babu.moger@amd.com> Cc: "Chang S. Bae" <chang.seok.bae@intel.com> Cc: "Sean J Christopherson" <sean.j.christopherson@intel.com> Cc: Frederic Weisbecker <frederic@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jann Horn <jannh@google.com> Cc: Juergen Gross <jgross@suse.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: kvm ML <kvm@vger.kernel.org> Cc: Masahiro Yamada <yamada.masahiro@socionext.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Nadav Amit <namit@vmware.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Pavel Tatashin <pasha.tatashin@oracle.com> Cc: Peter Feiner <pfeiner@google.com> Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org> Cc: "Radim Krčmář" <rkrcmar@redhat.com> Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Cc: Ravi V Shankar <ravi.v.shankar@intel.com> Cc: Sherry Hurwitz <sherry.hurwitz@amd.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Thomas Lendacky <Thomas.Lendacky@amd.com> Cc: x86 <x86@kernel.org> Link: https://lkml.kernel.org/r/1560794416-217638-2-git-send-email-fenghua.yu@intel.com
CVE-2019-1125
(cherry picked from commit acec0ce081de0c36459eea91647faf99296445a3) Signed-off-by: Tyler Hicks <tyhicks@canonical.com> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Borislav Petkov [Wed, 19 Jun 2019 15:24:34 +0000 (17:24 +0200)]
x86/cpufeatures: Carve out CQM features retrieval
... into a separate function for better readability. Split out from a
patch from Fenghua Yu <fenghua.yu@intel.com> to keep the mechanical,
sole code movement separate for easy review.
projects / mirror_ubuntu-bionic-kernel.git / log