A couple of calls in snd_pcm_oss_change_params_locked() ignore the
possible errors. Catch those errors and abort the operation for
avoiding further problems.
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20211201073606.11660-4-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Currently the driver is supporting only the interfaces QSGMII, SGMII,
RGMII and GMII. This patch extend the supported interfaces with
1000BASE-X and 2500BASE-X.
Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Link: https://lore.kernel.org/r/20211130101015.164916-1-horatiu.vultur@microchip.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
There is a error message within devm_ioremap_resource
already, so remove the dev_err call to avoid redundant
error message.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zou Wei <zou_wei@huawei.com>
Link: https://lore.kernel.org/r/1637822289-24534-1-git-send-email-zou_wei@huawei.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
coccinelle report：
./drivers/ata/libata-sata.c:830:8-16:
WARNING: use scnprintf or sprintf
Use sysfs_emit instead of scnprintf or sprintf makes more sense.
Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Yang Guang <yang.guang5@zte.com.cn>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
This reverts commit 239edf686c.
239edf686c ("PCI: aardvark: Fix support for PCI_ROM_ADDRESS1 on emulated
bridge") added support for the Type 1 Expansion ROM BAR at config offset
0x38, based on the register being listed in the Marvell Armada A3720 spec.
But the spec doesn't document it at all for RC mode, and there is no ROM in
the SOC, so remove this emulation for now.
The PCI bridge which represents aardvark's PCIe Root Port has an Expansion
ROM Base Address register at offset 0x30, but its meaning is different than
PCI's Expansion ROM BAR register, although the layout is the same. (This
is why we thought it does the same thing.)
First: there is no ROM (or part of BootROM) in the A3720 SOC dedicated for
PCIe Root Port (or controller in RC mode) containing executable code that
would initialize the Root Port, suitable for execution in bootloader (this
is how Expansion ROM BAR is used on x86).
Second: in A3720 spec the register (address 0xD0070030) is not documented
at all for Root Complex mode, but similar to other BAR registers, it has an
"entangled partner" in register 0xD0075920, which does address translation
for the BAR in 0xD0070030:
- the BAR register sets the address from the view of PCIe bus
- the translation register sets the address from the view of the CPU
The other BAR registers also have this entangled partner, and they can be
used to:
- in RC mode: address-checking on the receive side of the RC (they can
define address ranges for memory accesses from remote Endpoints to the
RC)
- in Endpoint mode: allow the remote CPU to access memory on A3720
The Expansion ROM BAR has only the Endpoint part documented, but from the
similarities we think that it can also be used in RC mode in that way.
So either Expansion ROM BAR has different meaning (if the hypothesis above
is true), or we don't know it's meaning (since it is not documented for RC
mode).
Remove the register from the emulated bridge accessing functions.
[bhelgaas: summarize reason for removal (first paragraph)]
Fixes: 239edf686c ("PCI: aardvark: Fix support for PCI_ROM_ADDRESS1 on emulated bridge")
Link: https://lore.kernel.org/r/20211125160148.26029-3-kabel@kernel.org
Signed-off-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Pali Rohár <pali@kernel.org>
In rvu_mbox_init(), mbox_regions is not freed or passed out
under the switch-default region, which could lead to a memory leak.
Fix this bug by changing 'return err' to 'goto free_regions'.
This bug was found by a static analyzer. The analysis employs
differential checking to identify inconsistent security operations
(e.g., checks or kfrees) between two code paths and confirms that the
inconsistent operations are not recovered in the current function or
the callers, so they constitute bugs.
Note that, as a bug found by static analysis, it can be a false
positive or hard to trigger. Multiple researchers have cross-reviewed
the bug.
Builds with CONFIG_OCTEONTX2_AF=y show no new warnings,
and our static analyzer no longer warns about this code.
Fixes: 98c5611163 (“octeontx2-af: cn10k: Add mbox support for CN10K platform”)
Signed-off-by: Zhou Qingyang <zhou1615@umn.edu>
Link: https://lore.kernel.org/r/20211130165039.192426-1-zhou1615@umn.edu
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
This reverts commit aeeecb8891.
The new SNMP variable (TCPSmallQueueFailure) can be incremented
for good reasons, even on a 100Gbit single TCP_STREAM flow.
If we really wanted to ease driver debugging [1], this would
require something more sophisticated.
[1] Usually, if a driver is delaying TX completions too much,
this can lead to stalls in TCP output. Various work arounds
have been used in the past, like skb_orphan() in ndo_start_xmit().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Menglong Dong <imagedong@tencent.com>
Link: https://lore.kernel.org/r/20211201033246.2826224-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
In mlx4_en_try_alloc_resources(), mlx4_en_copy_priv() is called and
tmp->tx_cq will be freed on the error path of mlx4_en_copy_priv().
After that mlx4_en_alloc_resources() is called and there is a dereference
of &tmp->tx_cq[t][i] in mlx4_en_alloc_resources(), which could lead to
a use after free problem on failure of mlx4_en_copy_priv().
Fix this bug by adding a check of mlx4_en_copy_priv()
This bug was found by a static analyzer. The analysis employs
differential checking to identify inconsistent security operations
(e.g., checks or kfrees) between two code paths and confirms that the
inconsistent operations are not recovered in the current function or
the callers, so they constitute bugs.
Note that, as a bug found by static analysis, it can be a false
positive or hard to trigger. Multiple researchers have cross-reviewed
the bug.
Builds with CONFIG_MLX4_EN=m show no new warnings,
and our static analyzer no longer warns about this code.
Fixes: ec25bc04ed ("net/mlx4_en: Add resilience in low memory systems")
Signed-off-by: Zhou Qingyang <zhou1615@umn.edu>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Link: https://lore.kernel.org/r/20211130164438.190591-1-zhou1615@umn.edu
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
IPCB/IP6CB need to be initialized when processing outbound v4 or v6 pkts
in the codepath of vrf device xmit function so that leftover garbage
doesn't cause futher code that uses the CB to incorrectly process the
pkt.
One occasion of the issue might occur when MPLS route uses the vrf
device as the outgoing device such as when the route is added using "ip
-f mpls route add <label> dev <vrf>" command.
The problems seems to exist since day one. Hence I put the day one
commits on the Fixes tags.
Fixes: 193125dbd8 ("net: Introduce VRF device driver")
Fixes: 35402e3136 ("net: Add IPv6 support to VRF device")
Cc: stable@vger.kernel.org
Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20211130162637.3249-1-ssuryaextr@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Program the 1ms autonegotiation clock divisor according to the clocking
rate of neta - without this, the 1ms clock ticks at about 660us on
Armada 38x configured for 250MHz. Bring this into correct specification.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Marek Behún <kabel@kernel.org>
Link: https://lore.kernel.org/r/E1ms4WD-00EKLK-Ld@rmk-PC.armlinux.org.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Tidy up the disable bit clearing where we clear a bit
and then run the link resolver.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Marek Behún <kabel@kernel.org>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/E1ms4Rx-00EKEc-En@rmk-PC.armlinux.org.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Russell King says:
====================
net: dsa: convert two drivers to phylink_generic_validate()
Patches 1 to 3 update core DSA code to allow drivers to be converted,
and patches 4 and 5 convert hellcreek and lantiq to use this (both of
which received reviewed-by from their maintainers.) As the rest have
yet to be reviewed by their maintainers, they are not included here.
Patch 1 had a request to change the formatting of it; I have not done
so as I believe a patch should do one change and one change only -
reformatting it is a separate change that should be in its own patch.
However, as patch 2 gets rid of the reason for reformatting it, it
would be pointless, and pure noise to include such an intermediary
patch.
Instead, I have swapped the order of patches 2 and 3 from the RFC
series.
====================
Link: https://lore.kernel.org/r/YaYiiU9nvmVugqnJ@shell.armlinux.org.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Populate the supported interfaces and MAC capabilities for the Lantiq
DSA switches and remove the old validate implementation to allow DSA to
use phylink_generic_validate() for this switch driver.
The exclusion of Gigabit linkmodes for MII, Reverse MII and Reduced MII
links is handled within phylink_generic_validate() in phylink, so there
is no need to make them conditional on the interface mode in the driver.
Reviewed-by: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Populate the supported interfaces and MAC capabilities for the
hellcreek DSA switch and remove the old validate implementation to
allow DSA to use phylink_generic_validate() for this switch driver.
The switch actually only supports MII and RGMII, but as phylib defaults
to GMII, we need to include this interface mode to keep existing DT
working.
Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de>
Tested-by: Kurt Kanzenbach <kurt@linutronix.de>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Support the use of phylink_generic_validate() when there is no
phylink_validate method given in the DSA switch operations and
mac_capabilities have been set in the phylink_config structure by the
DSA switch driver.
This gives DSA switch drivers the option to use this if they provide
the supported_interfaces and mac_capabilities, while still giving them
an option to override the default implementation if necessary.
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Marek Behún <kabel@kernel.org>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Phylink needs slightly more information than phylink_get_interfaces()
allows us to get from the DSA drivers - we need the MAC capabilities.
Replace the phylink_get_interfaces() method with phylink_get_caps() to
allow DSA drivers to fill in the phylink_config MAC capabilities field
as well.
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Marek Behún <kabel@kernel.org>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The code in port.c and slave.c creating the phylink instance is very
similar - let's consolidate this into a single function.
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Reviewed-by: Marek Behún <kabel@kernel.org>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
In qlcnic_83xx_add_rings(), the indirect function of
ahw->hw_ops->alloc_mbx_args will be called to allocate memory for
cmd.req.arg, and there is a dereference of it in qlcnic_83xx_add_rings(),
which could lead to a NULL pointer dereference on failure of the
indirect function like qlcnic_83xx_alloc_mbx_args().
Fix this bug by adding a check of alloc_mbx_args(), this patch
imitates the logic of mbx_cmd()'s failure handling.
This bug was found by a static analyzer. The analysis employs
differential checking to identify inconsistent security operations
(e.g., checks or kfrees) between two code paths and confirms that the
inconsistent operations are not recovered in the current function or
the callers, so they constitute bugs.
Note that, as a bug found by static analysis, it can be a false
positive or hard to trigger. Multiple researchers have cross-reviewed
the bug.
Builds with CONFIG_QLCNIC=m show no new warnings, and our
static analyzer no longer warns about this code.
Fixes: 7f9664525f ("qlcnic: 83xx memory map and HW access routine")
Signed-off-by: Zhou Qingyang <zhou1615@umn.edu>
Link: https://lore.kernel.org/r/20211130110848.109026-1-zhou1615@umn.edu
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
There's build error while CONFIG_REGMAP_MMIO is not set
and CONFIG_MDIO_MSCC_MIIM=m.
ERROR: modpost: "__devm_regmap_init_mmio_clk"
[drivers/net/mdio/mdio-mscc-miim.ko] undefined!
Add the depend of REGMAP_MMIO to fix it.
Fixes: a27a762828 ("net: mdio: mscc-miim: convert to a regmap implementation")
Signed-off-by: Tianchen Ding <dtcccc@linux.alibaba.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20211130110209.804536-1-dtcccc@linux.alibaba.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
No concurrent access is possible when a bitmap is local to a function.
So prefer the non-atomic functions to save a few cycles.
- replace a 'for' loop by an equivalent non-atomic 'bitmap_fill()' call
- use '__set_bit()'
While at it, clear the 'bitmask' bitmap only when needed.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/3de0792f5088f00d135c835df6c19e63ae95f5d2.1638026251.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The 'kprobe::data_size' is unsigned, thus it can not be negative. But if
user sets it enough big number (e.g. (size_t)-8), the result of 'data_size
+ sizeof(struct kretprobe_instance)' becomes smaller than sizeof(struct
kretprobe_instance) or zero. In result, the kretprobe_instance are
allocated without enough memory, and kretprobe accesses outside of
allocated memory.
To avoid this issue, introduce a max limitation of the
kretprobe::data_size. 4KB per instance should be OK.
Link: https://lkml.kernel.org/r/163836995040.432120.10322772773821182925.stgit@devnote2
Cc: stable@vger.kernel.org
Fixes: f47cd9b553 ("kprobes: kretprobe user entry-handler")
Reported-by: zhangyue <zhangyue1@kylinos.cn>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
When comparing two strings for the "onmatch" histogram trigger, fields
that are strings use string comparisons, which do not care about being
signed or not.
Do not fail to match two string fields if one is unsigned char array and
the other is a signed char array.
Link: https://lore.kernel.org/all/20211129123043.5cfd687a@gandalf.local.home/
Cc: stable@vgerk.kernel.org
Cc: Tom Zanussi <zanussi@kernel.org>
Cc: Yafang Shao <laoar.shao@gmail.com>
Fixes: b05e89ae7c ("tracing: Accept different type for synthetic event fields")
Reviewed-by: Masami Hiramatsu <mhiramatsu@kernel.org>
Reported-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Zero-length and one-element arrays are deprecated, see
Documentation/process/deprecated.rst
Flexible-array members should be used instead.
Generated by: scripts/coccinelle/misc/flexible_array.cocci
CC: Joey Gouly <joey.gouly@arm.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: kernel test robot <lkp@intel.com>
Signed-off-by: Julia Lawall <julia.lawall@inria.fr>
Link: https://lore.kernel.org/r/alpine.DEB.2.22.394.2111271859250.2864@hadrien
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
All the other mtk_hw_get_value() calls have a check for "if (err)" so
we can add one here as well. This silences a Smatch warning:
drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c:819 mtk_pinconf_bias_get_rsel()
error: uninitialized symbol 'pd'.
Fixes: fb34a9ae38 ("pinctrl: mediatek: support rsel feature")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20211127140836.GB24002@kili
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The "try_all_type" variable is not set if (hw->soc->pull_type) is false
leading to the following Smatch warning:
drivers/pinctrl/mediatek/pinctrl-paris.c:599 mtk_pctrl_show_one_pin()
error: uninitialized symbol 'try_all_type'.
Fixes: fb34a9ae38 ("pinctrl: mediatek: support rsel feature")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/20211127140750.GA24002@kili
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This ASSERT in xfs_rename is a) incorrect, because
(RENAME_WHITEOUT|RENAME_NOREPLACE) is a valid combination, and
b) unnecessary, because actual invalid flag combinations are already
handled at the vfs level in do_renameat2() before we get called.
So, remove it.
Reported-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
GPIO nodes are not themselves busses, so passing rockchip_bank_match
here is wrong. Passing NULL instead uses the standard bus match table
which is more appropriate.
devm_of_platform_populate() shows that this is the normal way to call
of_platform_populate() from a device driver, so in order to match that
more closely also add the pinctrl device as the parent for the newly
created GPIO controllers.
Specifically, using the wrong match here can break dynamic GPIO hogs as
marking the GPIO bank as a bus means that of_platform_notify() will set
OF_POPULATED on new child nodes and if this happens before
of_gpio_notify() is called then the new hog will be skipped as
OF_POPULATED is already set.
Fixes: 9ce9a02039 ("pinctrl/rockchip: drop the gpio related codes")
Signed-off-by: John Keeping <john@metanate.com>
Link: https://lore.kernel.org/r/20211126151352.1509583-1-john@metanate.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Convert the Cadence MACB/GEM Ethernet controller Device Tree binding
documentation to json-schema.
Re-add "cdns,gem" (removed in commit a217d8711d ("dt-bindings:
Remove PicoXcell bindings")) as there are active users on non-PicoXcell
platforms.
Add missing "ether_clk" clock.
Add missing properties.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/104dcbfd22f95fc77de9fe15e8abd83869603ea5.1637927673.git.geert@linux-m68k.org
Signed-off-by: Rob Herring <robh@kernel.org>
To improve human readability and enable automatic validation, the tuples
in "interrupts" properties should be grouped using angle brackets.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://lore.kernel.org/r/20211125150233.161576-1-geert@linux-m68k.org
Signed-off-by: Rob Herring <robh@kernel.org>
Both are already used by HW and drivers inside Linux.
Fix warnings as:
arch/arm64/boot/dts/freescale/fsl-ls1028a-kontron-sl28-var2.dt.yaml: ethernet@0,2: fixed-link:speed:0:0: 2500 is not one of [10, 100, 1000]
From schema: Documentation/devicetree/bindings/net/ethernet-controller.yaml
Signed-off-by: David Heidelberg <david@ixit.cz>
Link: https://lore.kernel.org/r/20211124202046.81136-1-david@ixit.cz
Signed-off-by: Rob Herring <robh@kernel.org>
Few Texas Instruments DC-DC converters on PMBus like TPS544B20 do not
have bindings and are used only as hardware monitoring sensor. These
devices are actually not trivial and can receive basic configuration
(e.g. power up mode, CNTL pin polarity, expected input voltage), however
devicetree support for configuration was never added.
Therefore in current state the devices are used only in read-only mode
and have trivial bindings, so document them to have basic dtschema
tests.
Cc: Vincent Pelletier <plr.vincent@gmail.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Link: https://lore.kernel.org/r/20211116110207.68494-1-krzysztof.kozlowski@canonical.com
Signed-off-by: Rob Herring <robh@kernel.org>
drm/i915 feature pull for v5.17:
Features and functionality:
- Implement per-lane DP drive settings for ICL+ (Ville)
- Enable runtime pm autosuspend by default (Tilak Tangudu)
- ADL-P DSI support (Vandita)
- Add support for pipe C and D DMC firmware (Anusha)
- Implement (near)atomic gamma LUT updates via vblank workers (Ville)
- Split plane updates to noarm+arm phases (Ville)
- Remove the CCS FB stride restrictions on ADL-P (Imre)
- Add PSR selective fetch support for biplanar formats (Jouni)
- Add support for display audio codec keepalive (Kai)
- VRR platform support for display 11 (Manasi)
Refactoring and cleanups:
- FBC refactoring and cleanups preparing for multiple FBC instances (Ville)
- PCH modeset refactoring, move to its own file (Ville)
- Refactor and simplify handling of modifiers (Imre)
- PXP cleanups (Ville)
- Display header and include refactoring (Jani)
- Some register macro cleanups (Ville)
- Refactor DP HDMI DFP limit code (Ville)
Fixes:
- Disable DSB usage for now due to incorrect gamma LUT updates (Ville)
- Check async flip state of every crtc and plane only once (José)
- Fix DPT FB suspend/resume (Imre)
- Fix black screen on reboot due to disabled DP++ TMDS output buffers (Ville)
- Don't request GMBUS to generate irqs when called while irqs are off (Ville)
- Fix type1 DVI DP dual mode adapter heuristics for modern platforms (Ville)
- Fix fix integer overflow in 128b/132b data rate calculation (Jani)
- Fix bigjoiner state readout (Ville)
- Build fix for non-x86 (Siva)
- PSR fixes (José, Jouni, Ville)
- Disable ADL-P underrun recovery (José)
- Fix DP link parameter usage before valid DPCD (Imre)
- VRR vblank and frame counter fixes (Ville)
- Fix fastsets on TypeC ports following a non-blocking modeset (Imre)
- Compiler warning fixes (Nathan Chancellor)
- Fix DSI HS mode commands (William Tseng)
- Error return fixes (Dan Carpenter)
- Update memory bandwidth calculations (Radhakrishna)
- Implement WM0 cursor WA for DG2 (Stan)
- Fix DSI Double pixelclock on read-back for dual-link panels (Hans de Goede)
- HDMI 2.1 PCON FRL configuration fixes (Ankit)
Merges:
- DP link training delay helpers, via topic branch (Jani)
- Backmerge drm-next (Jani)
Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/87v909it0t.fsf@intel.com
The automatic "save & restore" of interrupt context is a POWER10/XIVE2
feature exploited by KVM under the PowerNV platform. It is not
available under pSeries and the associated toggle should not be
exposed under the XIVE debugfs directory.
Introduce a platform handler for debugfs initialization and move the
'save-restore' entry under the native (PowerNV) backend to fix compile
when !CONFIG_PPC_POWERNV.
Fixes: 1e7684dc4f ("powerpc/xive: Add a debugfs toggle for save-restore")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211201165418.1041842-1-clg@kaod.org
There are cases that the TSC clocksource is wrongly judged as unstable by
the clocksource watchdog mechanism which tries to validate the TSC against
HPET, PM_TIMER or jiffies. While there is hardly a general reliable way to
check the validity of a watchdog, Thomas Gleixner proposed [1]:
"I'm inclined to lift that requirement when the CPU has:
1) X86_FEATURE_CONSTANT_TSC
2) X86_FEATURE_NONSTOP_TSC
3) X86_FEATURE_NONSTOP_TSC_S3
4) X86_FEATURE_TSC_ADJUST
5) At max. 4 sockets
After two decades of horrors we're finally at a point where TSC seems
to be halfway reliable and less abused by BIOS tinkerers. TSC_ADJUST
was really key as we can now detect even small modifications reliably
and the important point is that we can cure them as well (not pretty
but better than all other options)."
As feature #3 X86_FEATURE_NONSTOP_TSC_S3 only exists on several generations
of Atom processorz, and is always coupled with X86_FEATURE_CONSTANT_TSC
and X86_FEATURE_NONSTOP_TSC, skip checking it, and also be more defensive
to use maximal 2 sockets.
The check is done inside tsc_init() before registering 'tsc-early' and
'tsc' clocksources, as there were cases that both of them had been
wrongly judged as unreliable.
For more background of tsc/watchdog, there is a good summary in [2]
[tglx} Update vs. jiffies:
On systems where the only remaining clocksource aside of TSC is jiffies
there is no way to make this work because that creates a circular
dependency. Jiffies accuracy depends on not missing a periodic timer
interrupt, which is not guaranteed. That could be detected by TSC, but as
TSC is not trusted this cannot be compensated. The consequence is a
circulus vitiosus which results in shutting down TSC and falling back to
the jiffies clocksource which is even more unreliable.
[1]. https://lore.kernel.org/lkml/87eekfk8bd.fsf@nanos.tec.linutronix.de/
[2]. https://lore.kernel.org/lkml/87a6pimt1f.ffs@nanos.tec.linutronix.de/
[ tglx: Refine comment and amend changelog ]
Fixes: 6e3cd95234 ("x86/hpet: Use another crystalball to evaluate HPET usability")
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20211117023751.24190-2-feng.tang@intel.com
The TSC_ADJUST register is checked every time a CPU enters idle state, but
Thomas Gleixner mentioned there is still a caveat that a system won't enter
idle [1], either because it's too busy or configured purposely to not enter
idle.
Setup a periodic timer (every 10 minutes) to make sure the check is
happening on a regular base.
[1] https://lore.kernel.org/lkml/875z286xtk.fsf@nanos.tec.linutronix.de/
Fixes: 6e3cd95234 ("x86/hpet: Use another crystalball to evaluate HPET usability")
Requested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20211117023751.24190-1-feng.tang@intel.com
