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2020-08-21dt-bindings: iio: io-channel-mux: Fix compatible string in example codeChristian Eggers
commit add48ba425192c6e04ce70549129cacd01e2a09e upstream. The correct compatible string is "gpio-mux" (see bindings/mux/gpio-mux.txt). Cc: stable@vger.kernel.org # v4.13+ Reviewed-by: Peter Rosin <peda@axentia.se> Signed-off-by: Christian Eggers <ceggers@arri.de> Link: https://lore.kernel.org/r/20200727101605.24384-1-ceggers@arri.de Signed-off-by: Rob Herring <robh@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-19iio: improve IIO_CONCENTRATION channel type descriptionTomasz Duszynski
[ Upstream commit df16c33a4028159d1ba8a7061c9fa950b58d1a61 ] IIO_CONCENTRATION together with INFO_RAW specifier is used for reporting raw concentrations of pollutants. Raw value should be meaningless before being properly scaled. Because of that description shouldn't mention raw value unit whatsoever. Fix this by rephrasing existing description so it follows conventions used throughout IIO ABI docs. Fixes: 8ff6b3bc94930 ("iio: chemical: Add IIO_CONCENTRATION channel type") Signed-off-by: Tomasz Duszynski <tomasz.duszynski@octakon.com> Acked-by: Matt Ranostay <matt.ranostay@konsulko.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-07-22doc: dt: bindings: usb: dwc3: Update entries for disabling SS instances in ↵Neil Armstrong
park mode [ Upstream commit 3d157c28d2289edf0439e8308e8de3a06acaaf0e ] This patch updates the documentation with the information related to the quirks that needs to be added for disabling all SuperSpeed XHCI instances in park mode. Cc: Dongjin Kim <tobetter@gmail.com> Cc: Jianxin Pan <jianxin.pan@amlogic.com> Cc: Thinh Nguyen <thinhn@synopsys.com> Cc: Jun Li <lijun.kernel@gmail.com> Reported-by: Tim <elatllat@gmail.com> Signed-off-by: Neil Armstrong <narmstrong@baylibre.com> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Felipe Balbi <balbi@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-25mtd: rawnand: Pass a nand_chip object to nand_release()Boris Brezillon
[ Upstream commit 59ac276f22270fb2094910f9a734c17f41c25e70 ] Let's make the raw NAND API consistent by patching all helpers to take a nand_chip object instead of an mtd_info one. Now is nand_release()'s turn. Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-25mtd: rawnand: Pass a nand_chip object to nand_scan()Boris Brezillon
[ Upstream commit 00ad378f304a091ab2e2df5f944892a6ed558610 ] Let's make the raw NAND API consistent by patching all helpers to take a nand_chip object instead of an mtd_info one. We start with nand_scan(). Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-22dt-bindings: display: mediatek: control dpi pins mode to avoid leakageJitao Shi
[ Upstream commit b0ff9b590733079f7f9453e5976a9dd2630949e3 ] Add property "pinctrl-names" to swap pin mode between gpio and dpi mode. Set the dpi pins to gpio mode and output-low to avoid leakage current when dpi disabled. Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Jitao Shi <jitao.shi@mediatek.com> Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-22x86/kvm/hyper-v: Explicitly align hcall param for kvm_hyperv_exitJon Doron
[ Upstream commit f7d31e65368aeef973fab788aa22c4f1d5a6af66 ] The problem the patch is trying to address is the fact that 'struct kvm_hyperv_exit' has different layout on when compiling in 32 and 64 bit modes. In 64-bit mode the default alignment boundary is 64 bits thus forcing extra gaps after 'type' and 'msr' but in 32-bit mode the boundary is at 32 bits thus no extra gaps. This is an issue as even when the kernel is 64 bit, the userspace using the interface can be both 32 and 64 bit but the same 32 bit userspace has to work with 32 bit kernel. The issue is fixed by forcing the 64 bit layout, this leads to ABI change for 32 bit builds and while we are obviously breaking '32 bit userspace with 32 bit kernel' case, we're fixing the '32 bit userspace with 64 bit kernel' one. As the interface has no (known) users and 32 bit KVM is rather baroque nowadays, this seems like a reasonable decision. Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Jon Doron <arilou@gmail.com> Message-Id: <20200424113746.3473563-2-arilou@gmail.com> Reviewed-by: Roman Kagan <rvkagan@yandex-team.ru> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-06-10x86/speculation: Add Ivy Bridge to affected listJosh Poimboeuf
commit 3798cc4d106e91382bfe016caa2edada27c2bb3f upstream Make the docs match the code. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-10x86/speculation: Add SRBDS vulnerability and mitigation documentationMark Gross
commit 7222a1b5b87417f22265c92deea76a6aecd0fb0f upstream Add documentation for the SRBDS vulnerability and its mitigation. [ bp: Massage. jpoimboe: sysfs table strings. ] Signed-off-by: Mark Gross <mgross@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-10x86/speculation: Add Special Register Buffer Data Sampling (SRBDS) mitigationMark Gross
commit 7e5b3c267d256822407a22fdce6afdf9cd13f9fb upstream SRBDS is an MDS-like speculative side channel that can leak bits from the random number generator (RNG) across cores and threads. New microcode serializes the processor access during the execution of RDRAND and RDSEED. This ensures that the shared buffer is overwritten before it is released for reuse. While it is present on all affected CPU models, the microcode mitigation is not needed on models that enumerate ARCH_CAPABILITIES[MDS_NO] in the cases where TSX is not supported or has been disabled with TSX_CTRL. The mitigation is activated by default on affected processors and it increases latency for RDRAND and RDSEED instructions. Among other effects this will reduce throughput from /dev/urandom. * Enable administrator to configure the mitigation off when desired using either mitigations=off or srbds=off. * Export vulnerability status via sysfs * Rename file-scoped macros to apply for non-whitelist table initializations. [ bp: Massage, - s/VULNBL_INTEL_STEPPING/VULNBL_INTEL_STEPPINGS/g, - do not read arch cap MSR a second time in tsx_fused_off() - just pass it in, - flip check in cpu_set_bug_bits() to save an indentation level, - reflow comments. jpoimboe: s/Mitigated/Mitigation/ in user-visible strings tglx: Dropped the fused off magic for now ] Signed-off-by: Mark Gross <mgross@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Tested-by: Neelima Krishnan <neelima.krishnan@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-29arm64: errata: Hide CTR_EL0.DIC on systems affected by Neoverse-N1 #1542419James Morse
[ Upstream commit 05460849c3b51180d5ada3373d0449aea19075e4 ] Cores affected by Neoverse-N1 #1542419 could execute a stale instruction when a branch is updated to point to freshly generated instructions. To workaround this issue we need user-space to issue unnecessary icache maintenance that we can trap. Start by hiding CTR_EL0.DIC. Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> [ Removed cpu_enable_trap_ctr_access() hunk due to no 4afe8e79da92] Signed-off-by: James Morse <james.morse@arm.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-04-17ALSA: hda/realtek - Remove now-unnecessary XPS 13 headphone noise fixupsThomas Hebb
commit f36938aa7440f46a0a365f1cfde5f5985af2bef3 upstream. patch_realtek.c has historically failed to properly configure the PC Beep Hidden Register for the ALC256 codec (among others). Depending on your kernel version, symptoms of this misconfiguration can range from chassis noise, picked up by a poorly-shielded PCBEEP trace, getting amplified and played on your internal speaker and/or headphones to loud feedback, which responds to the "Headphone Mic Boost" ALSA control, getting played through your headphones. For details of the problem, see the patch in this series titled "ALSA: hda/realtek - Set principled PC Beep configuration for ALC256", which fixes the configuration. These symptoms have been most noticed on the Dell XPS 13 9350 and 9360, popular laptops that use the ALC256. As a result, several model-specific fixups have been introduced to try and fix the problem, the most egregious of which locks the "Headphone Mic Boost" control as a hack to minimize noise from a feedback loop that shouldn't have been there in the first place. Now that the underlying issue has been fixed, remove all these fixups. Remaining fixups needed by the XPS 13 are all picked up by existing pin quirks. This change should, for the XPS 13 9350/9360 - Significantly increase volume and audio quality on headphones - Eliminate headphone popping on suspend/resume - Allow "Headphone Mic Boost" to be set again, making the headphone jack fully usable as a microphone jack too. Fixes: 8c69729b4439 ("ALSA: hda - Fix headphone noise after Dell XPS 13 resume back from S3") Fixes: 423cd785619a ("ALSA: hda - Fix headphone noise on Dell XPS 13 9360") Fixes: e4c9fd10eb21 ("ALSA: hda - Apply headphone noise quirk for another Dell XPS 13 variant") Fixes: 1099f48457d0 ("ALSA: hda/realtek: Reduce the Headphone static noise on XPS 9350/9360") Cc: stable@vger.kernel.org Signed-off-by: Thomas Hebb <tommyhebb@gmail.com> Link: https://lore.kernel.org/r/b649a00edfde150cf6eebbb4390e15e0c2deb39a.1585584498.git.tommyhebb@gmail.com Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-17ALSA: doc: Document PC Beep Hidden Register on Realtek ALC256Thomas Hebb
commit f128090491c3f5aacef91a863f8c52abf869c436 upstream. This codec (among others) has a hidden set of audio routes, apparently designed to allow PC Beep output without a mixer widget on the output path, which are controlled by an undocumented Realtek vendor register. The default configuration of these routes means that certain inputs aren't accessible, necessitating driver control of the register. However, Realtek has provided no documentation of the register, instead opting to fix issues by providing magic numbers, most of which have been at least somewhat erroneous. These magic numbers then get copied by others into model-specific fixups, leading to a fragmented and buggy set of configurations. To get out of this situation, I've reverse engineered the register by flipping bits and observing how the codec's behavior changes. This commit documents my findings. It does not change any code. Cc: stable@vger.kernel.org Signed-off-by: Thomas Hebb <tommyhebb@gmail.com> Link: https://lore.kernel.org/r/bd69dfdeaf40ff31c4b7b797c829bb320031739c.1585584498.git.tommyhebb@gmail.com Signed-off-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-02dt-bindings: net: FMan erratum A050385Madalin Bucur
[ Upstream commit 26d5bb9e4c4b541c475751e015072eb2cbf70d15 ] FMAN DMA read or writes under heavy traffic load may cause FMAN internal resource leak; thus stopping further packet processing. The FMAN internal queue can overflow when FMAN splits single read or write transactions into multiple smaller transactions such that more than 17 AXI transactions are in flight from FMAN to interconnect. When the FMAN internal queue overflows, it can stall further packet processing. The issue can occur with any one of the following three conditions: 1. FMAN AXI transaction crosses 4K address boundary (Errata A010022) 2. FMAN DMA address for an AXI transaction is not 16 byte aligned, i.e. the last 4 bits of an address are non-zero 3. Scatter Gather (SG) frames have more than one SG buffer in the SG list and any one of the buffers, except the last buffer in the SG list has data size that is not a multiple of 16 bytes, i.e., other than 16, 32, 48, 64, etc. With any one of the above three conditions present, there is likelihood of stalled FMAN packet processing, especially under stress with multiple ports injecting line-rate traffic. To avoid situations that stall FMAN packet processing, all of the above three conditions must be avoided; therefore, configure the system with the following rules: 1. Frame buffers must not span a 4KB address boundary, unless the frame start address is 256 byte aligned 2. All FMAN DMA start addresses (for example, BMAN buffer address, FD[address] + FD[offset]) are 16B aligned 3. SG table and buffer addresses are 16B aligned and the size of SG buffers are multiple of 16 bytes, except for the last SG buffer that can be of any size. Additional workaround notes: - Address alignment of 64 bytes is recommended for maximally efficient system bus transactions (although 16 byte alignment is sufficient to avoid the stall condition) - To support frame sizes that are larger than 4K bytes, there are two options: 1. Large single buffer frames that span a 4KB page boundary can be converted into SG frames to avoid transaction splits at the 4KB boundary, 2. Align the large single buffer to 256B address boundaries, ensure that the frame address plus offset is 256B aligned. - If software generated SG frames have buffers that are unaligned and with random non-multiple of 16 byte lengths, before transmitting such frames via FMAN, frames will need to be copied into a new single buffer or multiple buffer SG frame that is compliant with the three rules listed above. Signed-off-by: Madalin Bucur <madalin.bucur@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-03-20driver core: Remove device link creation limitationRafael J. Wysocki
commit 515db266a9dace92b0cbaed9a6044dd5304b8ca9 upstream. If device_link_add() is called for a consumer/supplier pair with an existing device link between them and the existing link's type is not in agreement with the flags passed to that function by its caller, NULL will be returned. That is seriously inconvenient, because it forces the callers of device_link_add() to worry about what others may or may not do even if that is not relevant to them for any other reasons. It turns out, however, that this limitation can be made go away relatively easily. The underlying observation is that if DL_FLAG_STATELESS has been passed to device_link_add() in flags for the given consumer/supplier pair at least once, calling either device_link_del() or device_link_remove() to release the link returned by it should work, but there are no other requirements associated with that flag. In turn, if at least one of the callers of device_link_add() for the given consumer/supplier pair has not passed DL_FLAG_STATELESS to it in flags, the driver core should track the status of the link and act on it as appropriate (ie. the link should be treated as "managed"). This means that DL_FLAG_STATELESS needs to be set for managed device links and it should be valid to call device_link_del() or device_link_remove() to drop references to them in certain sutiations. To allow that to happen, introduce a new (internal) device link flag called DL_FLAG_MANAGED and make device_link_add() set it automatically whenever DL_FLAG_STATELESS is not passed to it. Also make it take additional references to existing device links that were previously stateless (that is, with DL_FLAG_STATELESS set and DL_FLAG_MANAGED unset) and will need to be managed going forward and initialize their status (which has been DL_STATE_NONE so far). Accordingly, when a managed device link is dropped automatically by the driver core, make it clear DL_FLAG_MANAGED, reset the link's status back to DL_STATE_NONE and drop the reference to it associated with DL_FLAG_MANAGED instead of just deleting it right away (to allow it to stay around in case it still needs to be released explicitly by someone). With that, since setting DL_FLAG_STATELESS doesn't mean that the device link in question is not managed any more, replace all of the status-tracking checks against DL_FLAG_STATELESS with analogous checks against DL_FLAG_MANAGED and update the documentation to reflect these changes. While at it, make device_link_add() reject flags that it does not recognize, including DL_FLAG_MANAGED. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Saravana Kannan <saravanak@google.com> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Review-by: Saravana Kannan <saravanak@google.com> Link: https://lore.kernel.org/r/2305283.AStDPdUUnE@kreacher Signed-off-by: Saravana Kannan <saravanak@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-20driver core: Add device link flag DL_FLAG_AUTOPROBE_CONSUMERRafael J. Wysocki
commit e7dd40105aac9ba051e44ad711123bc53a5e4c71 upstream. Add a new device link flag, DL_FLAG_AUTOPROBE_CONSUMER, to request the driver core to probe for a consumer driver automatically after binding a driver to the supplier device on a persistent managed device link. As unbinding the supplier driver on a managed device link causes the consumer driver to be detached from its device automatically, this flag provides a complementary mechanism which is needed to address some "composite device" use cases. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Saravana Kannan <saravanak@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-20driver core: Make driver core own stateful device linksRafael J. Wysocki
commit 72175d4ea4c442d95cf690c3e968eeee90fd43ca upstream. Even though stateful device links are managed by the driver core in principle, their creators are allowed and sometimes even expected to drop references to them via device_link_del() or device_link_remove(), but that doesn't really play well with the "persistent" link concept. If "persistent" managed device links are created from driver probe callbacks, device_link_add() called to do that will take a new reference on the link each time the callback runs and those references will never be dropped, which kind of isn't nice. This issues arises because of the link reference counting carried out by device_link_add() for existing links, but that is only done to avoid deleting device links that may still be necessary, which shouldn't be a concern for managed (stateful) links. These device links are managed by the driver core and whoever creates one of them will need it at least as long as until the consumer driver is detached from its device and deleting it may be left to the driver core just fine. For this reason, rework device_link_add() to apply the reference counting to stateless links only and make device_link_del() and device_link_remove() drop references to stateless links only too. After this change, if called to add a stateful device link for a consumer-supplier pair for which a stateful device link is present already, device_link_add() will return the existing link without incrementing its reference counter. Accordingly, device_link_del() and device_link_remove() will WARN() and do nothing when called to drop a reference to a stateful link. Thus, effectively, all stateful device links will be owned by the driver core. In addition, clean up the handling of the link management flags, DL_FLAG_AUTOREMOVE_CONSUMER and DL_FLAG_AUTOREMOVE_SUPPLIER, so that (a) they are never set at the same time and (b) if device_link_add() is called for a consumer-supplier pair with an existing stateful link between them, the flags of that link will be combined with the flags passed to device_link_add() to ensure that the life time of the link is sufficient for all of the callers of device_link_add() for the same consumer-supplier pair. Update the device_link_add() kerneldoc comment to reflect the above changes. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Saravana Kannan <saravanak@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-20driver core: Fix adding device links to probing suppliersRafael J. Wysocki
commit 15cfb094160385cc0b303c4cda483caa102af654 upstream. Currently, it is not valid to add a device link from a consumer driver ->probe callback to a supplier that is still probing too, but generally this is a valid use case. For example, if the consumer has just acquired a resource that can only be available if the supplier is functional, adding a device link to that supplier right away should be safe (and even desirable arguably), but device_link_add() doesn't handle that case correctly and the initial state of the link created by it is wrong then. To address this problem, change the initial state of device links added between a probing supplier and a probing consumer to DL_STATE_CONSUMER_PROBE and update device_links_driver_bound() to skip such links on the supplier side. With this change, if the supplier probe completes first, device_links_driver_bound() called for it will skip the link state update and when it is called for the consumer, the link state will be updated to "active". In turn, if the consumer probe completes first, device_links_driver_bound() called for it will change the state of the link to "active" and when it is called for the supplier, the link status update will be skipped. However, in principle the supplier or consumer probe may still fail after the link has been added, so modify device_links_no_driver() to change device links in the "active" or "consumer probe" state to "dormant" on the supplier side and update __device_links_no_driver() to change the link state to "available" only if it is "consumer probe" or "active". Then, if the supplier probe fails first, the leftover link to the probing consumer will become "dormant" and device_links_no_driver() called for the consumer (when its probe fails) will clean it up. In turn, if the consumer probe fails first, it will either drop the link, or change its state to "available" and, in the latter case, when device_links_no_driver() is called for the supplier, it will update the link state to "dormant". [If the supplier probe fails, but the consumer probe succeeds, which should not happen as long as the consumer driver is correct, the link still will be around, but it will be "dormant" until the supplier is probed again.] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Saravana Kannan <saravanak@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-20ACPI: watchdog: Allow disabling WDAT at bootJean Delvare
[ Upstream commit 3f9e12e0df012c4a9a7fd7eb0d3ae69b459d6b2c ] In case the WDAT interface is broken, give the user an option to ignore it to let a native driver bind to the watchdog device instead. Signed-off-by: Jean Delvare <jdelvare@suse.de> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-03-18cifs_atomic_open(): fix double-put on late allocation failureAl Viro
commit d9a9f4849fe0c9d560851ab22a85a666cddfdd24 upstream. several iterations of ->atomic_open() calling conventions ago, we used to need fput() if ->atomic_open() failed at some point after successful finish_open(). Now (since 2016) it's not needed - struct file carries enough state to make fput() work regardless of the point in struct file lifecycle and discarding it on failure exits in open() got unified. Unfortunately, I'd missed the fact that we had an instance of ->atomic_open() (cifs one) that used to need that fput(), as well as the stale comment in finish_open() demanding such late failure handling. Trivially fixed... Fixes: fe9ec8291fca "do_last(): take fput() on error after opening to out:" Cc: stable@kernel.org # v4.7+ Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-05netfilter: nf_flowtable: fix documentationMatteo Croce
commit 78e06cf430934fc3768c342cbebdd1013dcd6fa7 upstream. In the flowtable documentation there is a missing semicolon, the command as is would give this error: nftables.conf:5:27-33: Error: syntax error, unexpected devices, expecting newline or semicolon hook ingress priority 0 devices = { br0, pppoe-data }; ^^^^^^^ nftables.conf:4:12-13: Error: invalid hook (null) flowtable ft { ^^ Fixes: 19b351f16fd9 ("netfilter: add flowtable documentation") Signed-off-by: Matteo Croce <mcroce@redhat.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-05PM / devfreq: Add new name attribute for sysfsChanwoo Choi
commit 2fee1a7cc6b1ce6634bb0f025be2c94a58dfa34d upstream. The commit 4585fbcb5331 ("PM / devfreq: Modify the device name as devfreq(X) for sysfs") changed the node name to devfreq(x). After this commit, it is not possible to get the device name through /sys/class/devfreq/devfreq(X)/*. Add new name attribute in order to get device name. Cc: stable@vger.kernel.org Fixes: 4585fbcb5331 ("PM / devfreq: Modify the device name as devfreq(X) for sysfs") Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-29Documentation: Document arm64 kpti controlJeremy Linton
commit de19055564c8f8f9d366f8db3395836da0b2176c upstream. For a while Arm64 has been capable of force enabling or disabling the kpti mitigations. Lets make sure the documentation reflects that. Signed-off-by: Jeremy Linton <jeremy.linton@arm.com> Reviewed-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-27hwrng: omap3-rom - Fix missing clock by probing with device treeTony Lindgren
[ Upstream commit 0c0ef9ea6f3f0d5979dc7b094b0a184c1a94716b ] Commit 0ed266d7ae5e ("clk: ti: omap3: cleanup unnecessary clock aliases") removed old omap3 clock framework aliases but caused omap3-rom-rng to stop working with clock not found error. Based on discussions on the mailing list it was requested by Tero Kristo that it would be best to fix this issue by probing omap3-rom-rng using device tree to provide a proper clk property. The other option would be to add back the missing clock alias, but that does not help moving things forward with removing old legacy platform_data. Let's also add a proper device tree binding and keep it together with the fix. Cc: devicetree@vger.kernel.org Cc: Aaro Koskinen <aaro.koskinen@iki.fi> Cc: Adam Ford <aford173@gmail.com> Cc: Pali Rohár <pali.rohar@gmail.com> Cc: Rob Herring <robh+dt@kernel.org> Cc: Sebastian Reichel <sre@kernel.org> Cc: Tero Kristo <t-kristo@ti.com> Fixes: 0ed266d7ae5e ("clk: ti: omap3: cleanup unnecessary clock aliases") Reported-by: Aaro Koskinen <aaro.koskinen@iki.fi> Signed-off-by: Tony Lindgren <tony@atomide.com> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-27bus: ti-sysc: Add mcasp optional clocks flagTony Lindgren
[ Upstream commit 2c63a833e4500b341a62bf97e67488909ae12086 ] We have OPT_CLKS_NEEDED in legacy platform data, but it's missing from the ti-sysc driver for device tree based configuration. In order to pass OPT_CLKS_NEEDED quirk flag we need to update omap4 module data and add a new compatible for dra7 as the module layout is different from sysc_regbits_omap4_mcasp. Fixes: 70a65240efb1 ("bus: ti-sysc: Add register bits for interconnect target modules") Cc: Mark Rutland <mark.rutland@arm.com> Cc: Rob Herring <robh+dt@kernel.org> Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-27iio: fix position relative kernel versionEugen Hristev
[ Upstream commit 21eab7861688aa4c69fcb88440cc0c4a422bdcd6 ] Position relative channel type was added in 4.19 kernel version Fixes: "3055a6cfa04ba" ("iio: Add channel for Position Relative") Signed-off-by: Eugen Hristev <eugen.hristev@microchip.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-17mei: fix modalias documentationAlexander Usyskin
commit 73668309215285366c433489de70d31362987be9 upstream. mei client bus added the client protocol version to the device alias, but ABI documentation was not updated. Fixes: b26864cad1c9 (mei: bus: add client protocol version to the device alias) Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com> Signed-off-by: Tomas Winkler <tomas.winkler@intel.com> Link: https://lore.kernel.org/r/20191008005735.12707-1-tomas.winkler@intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-09dt-bindings: clock: renesas: rcar-usb2-clock-sel: Fix typo in exampleGeert Uytterhoeven
commit 830dbce7c76ea529decac7d23b808c1e7da3d891 upstream. The documented compatible value for R-Car H3 is "renesas,r8a7795-rcar-usb2-clock-sel", not "renesas,r8a77950-rcar-usb2-clock-sel". Fixes: 311accb64570db45 ("clk: renesas: rcar-usb2-clock-sel: Add R-Car USB 2.0 clock selector PHY") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Acked-by: Rob Herring <robh@kernel.org> Link: https://lore.kernel.org/r/20191016145650.30003-1-geert+renesas@glider.be Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-01-09ACPI: sysfs: Change ACPI_MASKABLE_GPE_MAX to 0x100Yunfeng Ye
commit a7583e72a5f22470d3e6fd3b6ba912892242339f upstream. The commit 0f27cff8597d ("ACPI: sysfs: Make ACPI GPE mask kernel parameter cover all GPEs") says: "Use a bitmap of size 0xFF instead of a u64 for the GPE mask so 256 GPEs can be masked" But the masking of GPE 0xFF it not supported and the check condition "gpe > ACPI_MASKABLE_GPE_MAX" is not valid because the type of gpe is u8. So modify the macro ACPI_MASKABLE_GPE_MAX to 0x100, and drop the "gpe > ACPI_MASKABLE_GPE_MAX" check. In addition, update the docs "Format" for acpi_mask_gpe parameter. Fixes: 0f27cff8597d ("ACPI: sysfs: Make ACPI GPE mask kernel parameter cover all GPEs") Signed-off-by: Yunfeng Ye <yeyunfeng@huawei.com> [ rjw: Use u16 as gpe data type in acpi_gpe_apply_masked_gpes() ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-12-17mm, thp, proc: report THP eligibility for each vmaMichal Hocko
[ Upstream commit 7635d9cbe8327e131a1d3d8517dc186c2796ce2e ] Userspace falls short when trying to find out whether a specific memory range is eligible for THP. There are usecases that would like to know that http://lkml.kernel.org/r/alpine.DEB.2.21.1809251248450.50347@chino.kir.corp.google.com : This is used to identify heap mappings that should be able to fault thp : but do not, and they normally point to a low-on-memory or fragmentation : issue. The only way to deduce this now is to query for hg resp. nh flags and confronting the state with the global setting. Except that there is also PR_SET_THP_DISABLE that might change the picture. So the final logic is not trivial. Moreover the eligibility of the vma depends on the type of VMA as well. In the past we have supported only anononymous memory VMAs but things have changed and shmem based vmas are supported as well these days and the query logic gets even more complicated because the eligibility depends on the mount option and another global configuration knob. Simplify the current state and report the THP eligibility in /proc/<pid>/smaps for each existing vma. Reuse transparent_hugepage_enabled for this purpose. The original implementation of this function assumes that the caller knows that the vma itself is supported for THP so make the core checks into __transparent_hugepage_enabled and use it for existing callers. __show_smap just use the new transparent_hugepage_enabled which also checks the vma support status (please note that this one has to be out of line due to include dependency issues). [mhocko@kernel.org: fix oops with NULL ->f_mapping] Link: http://lkml.kernel.org/r/20181224185106.GC16738@dhcp22.suse.cz Link: http://lkml.kernel.org/r/20181211143641.3503-3-mhocko@kernel.org Signed-off-by: Michal Hocko <mhocko@suse.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Dan Williams <dan.j.williams@intel.com> Cc: David Rientjes <rientjes@google.com> Cc: Jan Kara <jack@suse.cz> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: Paul Oppenheimer <bepvte@gmail.com> Cc: William Kucharski <william.kucharski@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-12-17USB: documentation: flags on usb-storage versus UASOliver Neukum
commit 65cc8bf99349f651a0a2cee69333525fe581f306 upstream. Document which flags work storage, UAS or both Signed-off-by: Oliver Neukum <oneukum@suse.com> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/20191114112758.32747-4-oneukum@suse.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-12-13rtc: dt-binding: abx80x: fix resistance scaleBaruch Siach
[ Upstream commit 73852e56827f5cb5db9d6e8dd8191fc2f2e8f424 ] The abracon,tc-resistor property value is in kOhm. Signed-off-by: Baruch Siach <baruch@tkos.co.il> Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-12-05HID: doc: fix wrong data structure reference for UHID_OUTPUTPeter Hutterer
[ Upstream commit 46b14eef59a8157138dc02f916a7f97c73b3ec53 ] Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net> Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-12-01x86/speculation: Fix incorrect MDS/TAA mitigation statusWaiman Long
commit 64870ed1b12e235cfca3f6c6da75b542c973ff78 upstream. For MDS vulnerable processors with TSX support, enabling either MDS or TAA mitigations will enable the use of VERW to flush internal processor buffers at the right code path. IOW, they are either both mitigated or both not. However, if the command line options are inconsistent, the vulnerabilites sysfs files may not report the mitigation status correctly. For example, with only the "mds=off" option: vulnerabilities/mds:Vulnerable; SMT vulnerable vulnerabilities/tsx_async_abort:Mitigation: Clear CPU buffers; SMT vulnerable The mds vulnerabilities file has wrong status in this case. Similarly, the taa vulnerability file will be wrong with mds mitigation on, but taa off. Change taa_select_mitigation() to sync up the two mitigation status and have them turned off if both "mds=off" and "tsx_async_abort=off" are present. Update documentation to emphasize the fact that both "mds=off" and "tsx_async_abort=off" have to be specified together for processors that are affected by both TAA and MDS to be effective. [ bp: Massage and add kernel-parameters.txt change too. ] Fixes: 1b42f017415b ("x86/speculation/taa: Add mitigation for TSX Async Abort") Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Borislav Petkov <bp@suse.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: linux-doc@vger.kernel.org Cc: Mark Gross <mgross@linux.intel.com> Cc: <stable@vger.kernel.org> Cc: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tim Chen <tim.c.chen@linux.intel.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Tyler Hicks <tyhicks@canonical.com> Cc: x86-ml <x86@kernel.org> Link: https://lkml.kernel.org/r/20191115161445.30809-2-longman@redhat.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-12-01spi: uniphier: fix incorrect property itemsKeiji Hayashibara
[ Upstream commit 3511ba7d4ca6f39e2d060bb94e42a41ad1fee7bf ] This commit fixes incorrect property because it was different from the actual. The parameters of '#address-cells' and '#size-cells' were removed, and 'interrupts', 'pinctrl-names' and 'pinctrl-0' were added. Fixes: 4dcd5c2781f3 ("spi: add DT bindings for UniPhier SPI controller") Signed-off-by: Keiji Hayashibara <hayashibara.keiji@socionext.com> Signed-off-by: Mark Brown <broonie@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-20net: phy: mdio-bcm-unimac: Allow configuring MDIO clock dividerFlorian Fainelli
[ Upstream commit b78ac6ecd1b6b46f8767cbafa95a7b0b51b87ad8 ] Allow the configuration of the MDIO clock divider when the Device Tree contains 'clock-frequency' property (similar to I2C and SPI buses). Because the hardware may have lost its state during suspend/resume, re-apply the MDIO clock divider upon resumption. Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-20media: dt-bindings: adv748x: Fix decimal unit addressesGeert Uytterhoeven
[ Upstream commit 27582f0ea97fe3e4a38beb98ab36cce4b6f029d5 ] With recent dtc and W=1: Warning (graph_port): video-receiver@70/port@10: graph node unit address error, expected "a" Warning (graph_port): video-receiver@70/port@11: graph node unit address error, expected "b" Unit addresses are always hexadecimal (without prefix), while the bases of reg property values depend on their prefixes. Fixes: e69595170b1cad85 ("media: adv748x: Add adv7481, adv7482 bindings") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Rob Herring <robh@kernel.org> Reviewed-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com> Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-11-12kvm: x86: mmu: Recovery of shattered NX large pagesJunaid Shahid
commit 1aa9b9572b10529c2e64e2b8f44025d86e124308 upstream. The page table pages corresponding to broken down large pages are zapped in FIFO order, so that the large page can potentially be recovered, if it is not longer being used for execution. This removes the performance penalty for walking deeper EPT page tables. By default, one large page will last about one hour once the guest reaches a steady state. Signed-off-by: Junaid Shahid <junaids@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-12kvm: mmu: ITLB_MULTIHIT mitigationPaolo Bonzini
commit b8e8c8303ff28c61046a4d0f6ea99aea609a7dc0 upstream. With some Intel processors, putting the same virtual address in the TLB as both a 4 KiB and 2 MiB page can confuse the instruction fetch unit and cause the processor to issue a machine check resulting in a CPU lockup. Unfortunately when EPT page tables use huge pages, it is possible for a malicious guest to cause this situation. Add a knob to mark huge pages as non-executable. When the nx_huge_pages parameter is enabled (and we are using EPT), all huge pages are marked as NX. If the guest attempts to execute in one of those pages, the page is broken down into 4K pages, which are then marked executable. This is not an issue for shadow paging (except nested EPT), because then the host is in control of TLB flushes and the problematic situation cannot happen. With nested EPT, again the nested guest can cause problems shadow and direct EPT is treated in the same way. [ tglx: Fixup default to auto and massage wording a bit ] Originally-by: Junaid Shahid <junaids@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-12kvm: Convert kvm_lock to a mutexJunaid Shahid
commit 0d9ce162cf46c99628cc5da9510b959c7976735b upstream. It doesn't seem as if there is any particular need for kvm_lock to be a spinlock, so convert the lock to a mutex so that sleepable functions (in particular cond_resched()) can be called while holding it. Signed-off-by: Junaid Shahid <junaids@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-12Documentation: Add ITLB_MULTIHIT documentationGomez Iglesias, Antonio
commit 7f00cc8d4a51074eb0ad4c3f16c15757b1ddfb7d upstream. Add the initial ITLB_MULTIHIT documentation. [ tglx: Add it to the index so it gets actually built. ] Signed-off-by: Antonio Gomez Iglesias <antonio.gomez.iglesias@intel.com> Signed-off-by: Nelson D'Souza <nelson.dsouza@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-12x86/bugs: Add ITLB_MULTIHIT bug infrastructureVineela Tummalapalli
commit db4d30fbb71b47e4ecb11c4efa5d8aad4b03dfae upstream. Some processors may incur a machine check error possibly resulting in an unrecoverable CPU lockup when an instruction fetch encounters a TLB multi-hit in the instruction TLB. This can occur when the page size is changed along with either the physical address or cache type. The relevant erratum can be found here: https://bugzilla.kernel.org/show_bug.cgi?id=205195 There are other processors affected for which the erratum does not fully disclose the impact. This issue affects both bare-metal x86 page tables and EPT. It can be mitigated by either eliminating the use of large pages or by using careful TLB invalidations when changing the page size in the page tables. Just like Spectre, Meltdown, L1TF and MDS, a new bit has been allocated in MSR_IA32_ARCH_CAPABILITIES (PSCHANGE_MC_NO) and will be set on CPUs which are mitigated against this issue. Signed-off-by: Vineela Tummalapalli <vineela.tummalapalli@intel.com> Co-developed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-12x86/speculation/taa: Add documentation for TSX Async AbortPawan Gupta
commit a7a248c593e4fd7a67c50b5f5318fe42a0db335e upstream. Add the documenation for TSX Async Abort. Include the description of the issue, how to check the mitigation state, control the mitigation, guidance for system administrators. [ bp: Add proper SPDX tags, touch ups by Josh and me. ] Co-developed-by: Antonio Gomez Iglesias <antonio.gomez.iglesias@intel.com> Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Antonio Gomez Iglesias <antonio.gomez.iglesias@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Mark Gross <mgross@linux.intel.com> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-12x86/tsx: Add "auto" option to the tsx= cmdline parameterPawan Gupta
commit 7531a3596e3272d1f6841e0d601a614555dc6b65 upstream. Platforms which are not affected by X86_BUG_TAA may want the TSX feature enabled. Add "auto" option to the TSX cmdline parameter. When tsx=auto disable TSX when X86_BUG_TAA is present, otherwise enable TSX. More details on X86_BUG_TAA can be found here: https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/tsx_async_abort.html [ bp: Extend the arg buffer to accommodate "auto\0". ] Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-12x86/cpu: Add a "tsx=" cmdline option with TSX disabled by defaultPawan Gupta
commit 95c5824f75f3ba4c9e8e5a4b1a623c95390ac266 upstream. Add a kernel cmdline parameter "tsx" to control the Transactional Synchronization Extensions (TSX) feature. On CPUs that support TSX control, use "tsx=on|off" to enable or disable TSX. Not specifying this option is equivalent to "tsx=off". This is because on certain processors TSX may be used as a part of a speculative side channel attack. Carve out the TSX controlling functionality into a separate compilation unit because TSX is a CPU feature while the TSX async abort control machinery will go to cpu/bugs.c. [ bp: - Massage, shorten and clear the arg buffer. - Clarifications of the tsx= possible options - Josh. - Expand on TSX_CTRL availability - Pawan. ] Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-12sched/fair: Fix low cpu usage with high throttling by removing expiration of ↵Dave Chiluk
cpu-local slices commit de53fd7aedb100f03e5d2231cfce0e4993282425 upstream. It has been observed, that highly-threaded, non-cpu-bound applications running under cpu.cfs_quota_us constraints can hit a high percentage of periods throttled while simultaneously not consuming the allocated amount of quota. This use case is typical of user-interactive non-cpu bound applications, such as those running in kubernetes or mesos when run on multiple cpu cores. This has been root caused to cpu-local run queue being allocated per cpu bandwidth slices, and then not fully using that slice within the period. At which point the slice and quota expires. This expiration of unused slice results in applications not being able to utilize the quota for which they are allocated. The non-expiration of per-cpu slices was recently fixed by 'commit 512ac999d275 ("sched/fair: Fix bandwidth timer clock drift condition")'. Prior to that it appears that this had been broken since at least 'commit 51f2176d74ac ("sched/fair: Fix unlocked reads of some cfs_b->quota/period")' which was introduced in v3.16-rc1 in 2014. That added the following conditional which resulted in slices never being expired. if (cfs_rq->runtime_expires != cfs_b->runtime_expires) { /* extend local deadline, drift is bounded above by 2 ticks */ cfs_rq->runtime_expires += TICK_NSEC; Because this was broken for nearly 5 years, and has recently been fixed and is now being noticed by many users running kubernetes (https://github.com/kubernetes/kubernetes/issues/67577) it is my opinion that the mechanisms around expiring runtime should be removed altogether. This allows quota already allocated to per-cpu run-queues to live longer than the period boundary. This allows threads on runqueues that do not use much CPU to continue to use their remaining slice over a longer period of time than cpu.cfs_period_us. However, this helps prevent the above condition of hitting throttling while also not fully utilizing your cpu quota. This theoretically allows a machine to use slightly more than its allotted quota in some periods. This overflow would be bounded by the remaining quota left on each per-cpu runqueueu. This is typically no more than min_cfs_rq_runtime=1ms per cpu. For CPU bound tasks this will change nothing, as they should theoretically fully utilize all of their quota in each period. For user-interactive tasks as described above this provides a much better user/application experience as their cpu utilization will more closely match the amount they requested when they hit throttling. This means that cpu limits no longer strictly apply per period for non-cpu bound applications, but that they are still accurate over longer timeframes. This greatly improves performance of high-thread-count, non-cpu bound applications with low cfs_quota_us allocation on high-core-count machines. In the case of an artificial testcase (10ms/100ms of quota on 80 CPU machine), this commit resulted in almost 30x performance improvement, while still maintaining correct cpu quota restrictions. That testcase is available at https://github.com/indeedeng/fibtest. Fixes: 512ac999d275 ("sched/fair: Fix bandwidth timer clock drift condition") Signed-off-by: Dave Chiluk <chiluk+linux@indeed.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Phil Auld <pauld@redhat.com> Reviewed-by: Ben Segall <bsegall@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: John Hammond <jhammond@indeed.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kyle Anderson <kwa@yelp.com> Cc: Gabriel Munos <gmunoz@netflix.com> Cc: Peter Oskolkov <posk@posk.io> Cc: Cong Wang <xiyou.wangcong@gmail.com> Cc: Brendan Gregg <bgregg@netflix.com> Link: https://lkml.kernel.org/r/1563900266-19734-2-git-send-email-chiluk+linux@indeed.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-06x86/xen: Return from panic notifierBoris Ostrovsky
[ Upstream commit c6875f3aacf2a5a913205accddabf0bfb75cac76 ] Currently execution of panic() continues until Xen's panic notifier (xen_panic_event()) is called at which point we make a hypercall that never returns. This means that any notifier that is supposed to be called later as well as significant part of panic() code (such as pstore writes from kmsg_dump()) is never executed. There is no reason for xen_panic_event() to be this last point in execution since panic()'s emergency_restart() will call into xen_emergency_restart() from where we can perform our hypercall. Nevertheless, we will provide xen_legacy_crash boot option that will preserve original behavior during crash. This option could be used, for example, if running kernel dumper (which happens after panic notifiers) is undesirable. Reported-by: James Dingwall <james@dingwall.me.uk> Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com> Reviewed-by: Juergen Gross <jgross@suse.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-10-17USB: rio500: Remove Rio 500 kernel driverBastien Nocera
commit 015664d15270a112c2371d812f03f7c579b35a73 upstream. The Rio500 kernel driver has not been used by Rio500 owners since 2001 not long after the rio500 project added support for a user-space USB stack through the very first versions of usbdevfs and then libusb. Support for the kernel driver was removed from the upstream utilities in 2008: https://gitlab.freedesktop.org/hadess/rio500/commit/943f624ab721eb8281c287650fcc9e2026f6f5db Cc: Cesar Miquel <miquel@df.uba.ar> Signed-off-by: Bastien Nocera <hadess@hadess.net> Cc: stable <stable@vger.kernel.org> Link: https://lore.kernel.org/r/6251c17584d220472ce882a3d9c199c401a51a71.camel@hadess.net Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-11arm64/speculation: Support 'mitigations=' cmdline optionJosh Poimboeuf
commit a111b7c0f20e13b54df2fa959b3dc0bdf1925ae6 upstream. Configure arm64 runtime CPU speculation bug mitigations in accordance with the 'mitigations=' cmdline option. This affects Meltdown, Spectre v2, and Speculative Store Bypass. The default behavior is unchanged. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> [will: reorder checks so KASLR implies KPTI and SSBS is affected by cmdline] Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-10-11arm64: Provide a command line to disable spectre_v2 mitigationJeremy Linton
[ Upstream commit e5ce5e7267ddcbe13ab9ead2542524e1b7993e5a ] There are various reasons, such as benchmarking, to disable spectrev2 mitigation on a machine. Provide a command-line option to do so. Signed-off-by: Jeremy Linton <jeremy.linton@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Andre Przywara <andre.przywara@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Tested-by: Stefan Wahren <stefan.wahren@i2se.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: linux-doc@vger.kernel.org Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>