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2019-12-02drm/panel: Add generic DSI display controller YAML bindingsLinus Walleij
This adds a starting point for processing and defining generic bindings used by DSI display controllers and panels attached to the virtual DSI ports. Cc: Stephan Gerhold <stephan@gerhold.net> Cc: devicetree@vger.kernel.org Suggested-by: Rob Herring <robh@kernel.org> Link: https://patchwork.freedesktop.org/patch/msgid/20191128090726.51107-1-linus.walleij@linaro.org Reviewed-by: Rob Herring <robh@kernel.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-11-30dt-bindings: Add Logic PD Type 28 display panelAdam Ford
This patch adds documentation of device tree bindings for the WVGA panel Logic PD Type 28 display. Signed-off-by: Adam Ford <aford173@gmail.com> Reviewed-by: Rob Herring <robh@kernel.org> Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Link: https://patchwork.freedesktop.org/patch/msgid/20191016135147.7743-2-aford173@gmail.com
2019-11-29drm: Inline drm_color_lut_extract()Ville Syrjälä
This thing can get called several thousand times per LUT so seems like we want to inline it to: - avoid the function call overhead - allow constant folding A quick synthetic test (w/o any hardware interaction) with a ridiculously large LUT size shows about 50% reduction in runtime on my HSW and BSW boxes. Slightly less with more reasonable LUT size but still easily measurable in tens of microseconds. v2: Include drm_color_mgmt.h in the .rst (Daniel) Cc: Daniel Vetter <daniel@ffwll.ch> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com> Link: https://patchwork.freedesktop.org/patch/msgid/20191108135654.12907-1-ville.syrjala@linux.intel.com
2019-11-29drm/todo: Add entry for fb funcs related cleanupsDaniel Vetter
We're doing a great job for really simple drivers right now, but still a lot of boilerplate for the bigger ones. Acked-by: Thomas Zimmermann <tzimmermann@suse.de> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20191127180035.416209-3-daniel.vetter@ffwll.ch
2019-11-14drm/panel: Add DT bindings for Sony ACX424AKPLinus Walleij
This adds device tree bindings for the Sony ACX424AKP panel. Let's use YAML. Cc: devicetree@vger.kernel.org Reviewed-by: Rob Herring <robh@kernel.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Link: https://patchwork.freedesktop.org/patch/msgid/20191114131525.3988-1-linus.walleij@linaro.org
2019-11-07drm/todo: Convert drivers to generic fbdev emulationThomas Zimmermann
This replaces the original TODO item for drm_fb_helper_fbdev_setup() and _teardown(), which are deprecated. v2: * remove driver-specific comments * list some basic requirements * keep a TODO item on drm_fb_helper_init() Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Noralf Trønnes <noralf@tronnes.org> Link: https://patchwork.freedesktop.org/patch/msgid/20191106124727.11641-2-tzimmermann@suse.de
2019-11-04drm/doc: Update IGT documentationLeandro Ribeiro
The IGT documentation in this page is telling us to build it using make. According to commit 67993c1 ("automake: Point builders at meson") from the IGT project, this is deprecated and IGT should be built with meson. Instead of having a documentation for IGT in this page, point to their GitLab README, which should always be up to date. Signed-off-by: Leandro Ribeiro <leandrohr@riseup.net> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: https://patchwork.freedesktop.org/patch/msgid/20191030011211.47942-1-leandrohr@riseup.net
2019-11-04drm/todo: Add entry to remove load/unload hooksDaniel Vetter
They're midlayer, broken, and because of the old gunk, we can't fix them. For examples see the various checks in drm_mode_object.c against dev->registered, which cannot be enforced if the driver still uses the load hook. Unfortunately our biggest driver still uses load/unload, so this would be really great to get fixed. Cc: Alex Deucher <alexander.deucher@amd.com> Cc: Harry Wentland <harry.wentland@amd.com> Reviewed-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20191023144953.28190-2-daniel.vetter@ffwll.ch
2019-10-28drm/todo: Clarify situation around fbdev and defioThomas Zimmermann
The TODO item is misleading and makes it seem as if fbdev emulation cannot be used with SHMEM. Rephrase the text to describe the current situation more correctly. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Acked-by: Noralf Trønnes <noralf@tronnes.org> Link: https://patchwork.freedesktop.org/patch/msgid/20191025092759.13069-3-tzimmermann@suse.de
2019-10-25doc: drm: Update references to previously renamed filesAnna Karas
Update references to reservation.c and reservation.h since these files have been renamed to dma-resv.c and dma-resv.h respectively. Cc: Christian König <christian.koenig@amd.com> Link: https://patchwork.freedesktop.org/patch/323401/?series=65037&rev=1 Signed-off-by: Anna Karas <anna.karas@intel.com> Reviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Link: https://patchwork.freedesktop.org/patch/msgid/20190927111504.20136-1-anna.karas@intel.com
2019-10-23Merge drm/drm-next into drm-misc-nextSean Paul
Parroting Daniel's backmerge justification from 2e79e22e092acd55da0b2db066e4826d7d152c41: Thierry needs fd70c7755bf0 ("drm/bridge: tc358767: fix max_tu_symbol value") to be able to merge his dp_link patch series. Signed-off-by: Sean Paul <seanpaul@chromium.org>
2019-10-23Merge v5.4-rc4 into drm-nextDaniel Vetter
Thierry needs fd70c7755bf0 ("drm/bridge: tc358767: fix max_tu_symbol value") to be able to merge his dp_link patch series. Some adjacent changes conflicts, plus some clashes in i915 due to cherry-picking and git trying to be helpful and leaving both versions in. Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2019-10-23drm/todo: Add levelsDaniel Vetter
Should help new people pick suitable tasks. Cc: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com> Cc: Manasi Navare <manasi.d.navare@intel.com> Cc: Sean Paul <sean@poorly.run> Reviewed-by: Sean Paul <sean@poorly.run> Acked-by: Thomas Zimmermann <tzimmermann@suse.de> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20191022152530.22038-2-daniel.vetter@ffwll.ch
2019-10-23drm/todo: Remove i915 device_link taskDaniel Vetter
Done with commit aef9f33b7658a7489f71df5d6e6ecb47f2521e8a Author: Imre Deak <imre.deak@intel.com> Date: Tue Oct 23 17:43:10 2018 +0300 drm/i915: Ensure proper HDA suspend/resume ordering with a device link Cc: Imre Deak <imre.deak@intel.com> Reviewed-by: Sean Paul <sean@poorly.run> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: https://patchwork.freedesktop.org/patch/msgid/20191022152530.22038-1-daniel.vetter@ffwll.ch
2019-10-22Merge tag 'du-next-20191016' of git://linuxtv.org/pinchartl/media into drm-nextDave Airlie
- R-Car DU support for R8A774B1 SoC - R-Car DU fixes for H2 ES2.0 and later revisions Signed-off-by: Dave Airlie <airlied@redhat.com> From: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Link: https://patchwork.freedesktop.org/patch/msgid/20191015215116.GF19403@pendragon.ideasonboard.com
2019-10-22Merge tag 'mediatek-drm-next-5.5' of ↵Dave Airlie
https://github.com/ckhu-mediatek/linux.git-tags into drm-next Mediatek DRM next for Linux 5.5 This include mipi_tx, dsi, and partial crtc for MT8183 SoC. Signed-off-by: Dave Airlie <airlied@redhat.com> From: CK Hu <ck.hu@mediatek.com> Link: https://patchwork.freedesktop.org/patch/msgid/1571103548.4416.6.camel@mtksdaap41
2019-10-20Merge branch 'irq-urgent-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq fixes from Thomas Gleixner: "A small set of irq chip driver fixes and updates: - Update the SIFIVE PLIC interrupt driver to use the fasteoi handler to address the shortcomings of the existing flow handling which was prone to lose interrupts - Use the proper limit for GIC interrupt line numbers - Add retrigger support for the recently merged Anapurna Labs Fabric interrupt controller to make it complete - Enable the ATMEL AIC5 interrupt controller driver on the new SAM9X60 SoC" * 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: irqchip/sifive-plic: Switch to fasteoi flow irqchip/gic-v3: Fix GIC_LINE_NR accessor irqchip/atmel-aic5: Add support for sam9x60 irqchip irqchip/al-fic: Add support for irq retrigger
2019-10-19Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netLinus Torvalds
Pull networking fixes from David Miller: "I was battling a cold after some recent trips, so quite a bit piled up meanwhile, sorry about that. Highlights: 1) Fix fd leak in various bpf selftests, from Brian Vazquez. 2) Fix crash in xsk when device doesn't support some methods, from Magnus Karlsson. 3) Fix various leaks and use-after-free in rxrpc, from David Howells. 4) Fix several SKB leaks due to confusion of who owns an SKB and who should release it in the llc code. From Eric Biggers. 5) Kill a bunc of KCSAN warnings in TCP, from Eric Dumazet. 6) Jumbo packets don't work after resume on r8169, as the BIOS resets the chip into non-jumbo mode during suspend. From Heiner Kallweit. 7) Corrupt L2 header during MPLS push, from Davide Caratti. 8) Prevent possible infinite loop in tc_ctl_action, from Eric Dumazet. 9) Get register bits right in bcmgenet driver, based upon chip version. From Florian Fainelli. 10) Fix mutex problems in microchip DSA driver, from Marek Vasut. 11) Cure race between route lookup and invalidation in ipv4, from Wei Wang. 12) Fix performance regression due to false sharing in 'net' structure, from Eric Dumazet" * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (145 commits) net: reorder 'struct net' fields to avoid false sharing net: dsa: fix switch tree list net: ethernet: dwmac-sun8i: show message only when switching to promisc net: aquantia: add an error handling in aq_nic_set_multicast_list net: netem: correct the parent's backlog when corrupted packet was dropped net: netem: fix error path for corrupted GSO frames macb: propagate errors when getting optional clocks xen/netback: fix error path of xenvif_connect_data() net: hns3: fix mis-counting IRQ vector numbers issue net: usb: lan78xx: Connect PHY before registering MAC vsock/virtio: discard packets if credit is not respected vsock/virtio: send a credit update when buffer size is changed mlxsw: spectrum_trap: Push Ethernet header before reporting trap net: ensure correct skb->tstamp in various fragmenters net: bcmgenet: reset 40nm EPHY on energy detect net: bcmgenet: soft reset 40nm EPHYs before MAC init net: phy: bcm7xxx: define soft_reset for 40nm EPHY net: bcmgenet: don't set phydev->link from MAC net: Update address for MediaTek ethernet driver in MAINTAINERS ipv4: fix race condition between route lookup and invalidation ...
2019-10-17Merge tag 'arm64-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 fixes from Will Deacon: "The main thing here is a long-awaited workaround for a CPU erratum on ThunderX2 which we have developed in conjunction with engineers from Cavium/Marvell. At the moment, the workaround is unconditionally enabled for affected CPUs at runtime but we may add a command-line option to disable it in future if performance numbers show up indicating a significant cost for real workloads. Summary: - Work around Cavium/Marvell ThunderX2 erratum #219 - Fix regression in mlock() ABI caused by sign-extension of TTBR1 addresses - More fixes to the spurious kernel fault detection logic - Fix pathological preemption race when enabling some CPU features at boot - Drop broken kcore macros in favour of generic implementations - Fix userspace view of ID_AA64ZFR0_EL1 when SVE is disabled - Avoid NULL dereference on allocation failure during hibernation" * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: arm64: tags: Preserve tags for addresses translated via TTBR1 arm64: mm: fix inverted PAR_EL1.F check arm64: sysreg: fix incorrect definition of SYS_PAR_EL1_F arm64: entry.S: Do not preempt from IRQ before all cpufeatures are enabled arm64: hibernate: check pgd table allocation arm64: cpufeature: Treat ID_AA64ZFR0_EL1 as RAZ when SVE is not enabled arm64: Fix kcore macros after 52-bit virtual addressing fallout arm64: Allow CAVIUM_TX2_ERRATUM_219 to be selected arm64: Avoid Cavium TX2 erratum 219 when switching TTBR arm64: Enable workaround for Cavium TX2 erratum 219 when running SMT arm64: KVM: Trap VM ops when ARM64_WORKAROUND_CAVIUM_TX2_219_TVM is set
2019-10-17Merge branch 'errata/tx2-219' into for-next/fixesWill Deacon
Workaround for Cavium/Marvell ThunderX2 erratum #219. * errata/tx2-219: arm64: Allow CAVIUM_TX2_ERRATUM_219 to be selected arm64: Avoid Cavium TX2 erratum 219 when switching TTBR arm64: Enable workaround for Cavium TX2 erratum 219 when running SMT arm64: KVM: Trap VM ops when ARM64_WORKAROUND_CAVIUM_TX2_219_TVM is set
2019-10-17drm/i915/huc: improve documentationDaniele Ceraolo Spurio
Better explain the usage of the microcontroller and what i915 is responsible of. While at it, fix the documentation for the auth function, which doesn't do any pinning anymore. v2: add a comment on HuC being optional and descrive how HuC accesses memory (Martin) v3: add extra newline for better text organization (Martin) Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com> Cc: Michal Wajdeczko <michal.wajdeczko@intel.com> Cc: Martin Peres <martin.peres@linux.intel.com> Acked-by: Anna Karas <anna.karas@intel.com> Reviewed-by: Martin Peres <martin.peres@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20191014183602.3643-3-daniele.ceraolospurio@intel.com
2019-10-17drm/i915/guc: improve documentationDaniele Ceraolo Spurio
Add a short description of what we expect from GuC and some minor improvements to existing documentation. Also remove a comment about a difference between GuC and HuC that is not true anymore. v2: add that the GuC is not mandatory (Martin) v3: add extra newline for better text organization (Martin) Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com> Cc: Michal Wajdeczko <michal.wajdeczko@intel.com> Cc: Matthew Brost <matthew.brost@intel.com> Cc: Martin Peres <martin.peres@linux.intel.com> Acked-by: Anna Karas <anna.karas@intel.com> Reviewed-by: Martin Peres <martin.peres@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20191014183602.3643-2-daniele.ceraolospurio@intel.com
2019-10-17drm/i915: Add microcontrollers documentation sectionDaniele Ceraolo Spurio
To better organize the information, add a microcontrollers section and move/link the GuC, HuC and DMC documentation under it. Also add a small intro. Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com> Cc: Michal Wajdeczko <michal.wajdeczko@intel.com> Acked-by: Anna Karas <anna.karas@intel.com> Reviewed-by: Martin Peres <martin.peres@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20191014183602.3643-1-daniele.ceraolospurio@intel.com
2019-10-17dt/bindings: display: Add optional property node define for Mali DP500Wen He
Add optional property node 'arm,malidp-arqos-value' for the Mali DP500. This property describe the ARQoS levels of DP500's QoS signaling. Signed-off-by: Wen He <wen.he_1@nxp.com> Reviewed-by: Rob Herring <robh@kernel.org> Signed-off-by: Liviu Dudau <liviu.dudau@arm.com> Link: https://patchwork.freedesktop.org/patch/msgid/20190910075913.17650-1-wen.he_1@nxp.com
2019-10-17drm: Add TODO item for fbdev driver conversionThomas Zimmermann
The DRM TODO list now contains an entry for converting fbdev drivers over to DRM. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: https://patchwork.freedesktop.org/patch/msgid/20191017074705.9140-2-tzimmermann@suse.de
2019-10-16dt-bindings: display: renesas: Add r8a774b1 supportBiju Das
Document RZ/G2N (R8A774B1) SoC bindings. Signed-off-by: Biju Das <biju.das@bp.renesas.com> Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
2019-10-16dt-bindings: display: renesas: lvds: Document r8a774b1 bindingsBiju Das
Document the RZ/G2N (R8A774B1) LVDS bindings. Signed-off-by: Biju Das <biju.das@bp.renesas.com> Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Acked-by: Rob Herring <robh@kernel.org>
2019-10-16dt-bindings: display: renesas: du: Document the r8a774b1 bindingsBiju Das
Document the RZ/G2N (R8A774B1) SoC in the R-Car DU bindings. Signed-off-by: Biju Das <biju.das@bp.renesas.com> Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Acked-by: Rob Herring <robh@kernel.org>
2019-10-14mm, page_owner: decouple freeing stack trace from debug_pageallocVlastimil Babka
Commit 8974558f49a6 ("mm, page_owner, debug_pagealloc: save and dump freeing stack trace") enhanced page_owner to also store freeing stack trace, when debug_pagealloc is also enabled. KASAN would also like to do this [1] to improve error reports to debug e.g. UAF issues. Kirill has suggested that the freeing stack trace saving should be also possible to be enabled separately from KASAN or debug_pagealloc, i.e. with an extra boot option. Qian argued that we have enough options already, and avoiding the extra overhead is not worth the complications in the case of a debugging option. Kirill noted that the extra stack handle in struct page_owner requires 0.1% of memory. This patch therefore enables free stack saving whenever page_owner is enabled, regardless of whether debug_pagealloc or KASAN is also enabled. KASAN kernels booted with page_owner=on will thus benefit from the improved error reports. [1] https://bugzilla.kernel.org/show_bug.cgi?id=203967 [vbabka@suse.cz: v3] Link: http://lkml.kernel.org/r/20191007091808.7096-3-vbabka@suse.cz Link: http://lkml.kernel.org/r/20190930122916.14969-3-vbabka@suse.cz Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Qian Cai <cai@lca.pw> Suggested-by: Dmitry Vyukov <dvyukov@google.com> Suggested-by: Walter Wu <walter-zh.wu@mediatek.com> Suggested-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Suggested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Suggested-by: Qian Cai <cai@lca.pw> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-10-14Merge tag 'irqchip-fixes-5.4-1' of ↵Thomas Gleixner
git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/urgent Pull irqchip fixes from Marc Zyngier: - Add retrigger support to Amazon's al-fic driver - Add SAM9X60 support to Atmel's AIC5 irqchip - Fix GICv3 maximum interrupt calculation - Convert SiFive's PLIC to the fasteoi IRQ flow
2019-10-13Merge tag 'hwmon-for-v5.4-rc3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging Pull hwmon fixes from Guenter Roeck: - Update/fix inspur-ipsps1 and k10temp Documentation - Fix nct7904 driver - Fix HWMON_P_MIN_ALARM mask in hwmon core * tag 'hwmon-for-v5.4-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging: hwmon: docs: Extend inspur-ipsps1 title underline hwmon: (nct7904) Add array fan_alarm and vsen_alarm to store the alarms in nct7904_data struct. docs: hwmon: Include 'inspur-ipsps1.rst' into docs hwmon: Fix HWMON_P_MIN_ALARM mask hwmon: (k10temp) Update documentation and add temp2_input info hwmon: (nct7904) Fix the incorrect value of vsen_mask in nct7904_data struct
2019-10-12Merge tag 'tty-5.4-rc3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty/serial driver fixes from Greg KH: "Here are some small tty and serial driver fixes for 5.4-rc3 that resolve a number of reported issues and regressions. None of these are huge, full details are in the shortlog. There's also a MAINTAINERS update that I think you might have already taken in your tree already, but git should handle that merge easily. All have been in linux-next with no reported issues" * tag 'tty-5.4-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: MAINTAINERS: kgdb: Add myself as a reviewer for kgdb/kdb tty: serial: imx: Use platform_get_irq_optional() for optional IRQs serial: fix kernel-doc warning in comments serial: 8250_omap: Fix gpio check for auto RTS/CTS serial: mctrl_gpio: Check for NULL pointer tty: serial: fsl_lpuart: Fix lpuart_flush_buffer() tty: serial: Fix PORT_LINFLEXUART definition tty: n_hdlc: fix build on SPARC serial: uartps: Fix uartps_major handling serial: uartlite: fix exit path null pointer tty: serial: linflexuart: Fix magic SysRq handling serial: sh-sci: Use platform_get_irq_optional() for optional interrupts dt-bindings: serial: sh-sci: Document r8a774b1 bindings serial/sifive: select SERIAL_EARLYCON tty: serial: rda: Fix the link time qualifier of 'rda_uart_exit()' tty: serial: owl: Fix the link time qualifier of 'owl_uart_exit()'
2019-10-12Merge tag 'usb-5.4-rc3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb Pull USB fixes from Greg KH: "Here are a lot of small USB driver fixes for 5.4-rc3. syzbot has stepped up its testing of the USB driver stack, now able to trigger fun race conditions between disconnect and probe functions. Because of that we have a lot of fixes in here from Johan and others fixing these reported issues that have been around since almost all time. We also are just deleting the rio500 driver, making all of the syzbot bugs found in it moot as it turns out no one has been using it for years as there is a userspace version that is being used instead. There are also a number of other small fixes in here, all resolving reported issues or regressions. All have been in linux-next without any reported issues" * tag 'usb-5.4-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (65 commits) USB: yurex: fix NULL-derefs on disconnect USB: iowarrior: use pr_err() USB: iowarrior: drop redundant iowarrior mutex USB: iowarrior: drop redundant disconnect mutex USB: iowarrior: fix use-after-free after driver unbind USB: iowarrior: fix use-after-free on release USB: iowarrior: fix use-after-free on disconnect USB: chaoskey: fix use-after-free on release USB: adutux: fix use-after-free on release USB: ldusb: fix NULL-derefs on driver unbind USB: legousbtower: fix use-after-free on release usb: cdns3: Fix for incorrect DMA mask. usb: cdns3: fix cdns3_core_init_role() usb: cdns3: gadget: Fix full-speed mode USB: usb-skeleton: drop redundant in-urb check USB: usb-skeleton: fix use-after-free after driver unbind USB: usb-skeleton: fix NULL-deref on disconnect usb:cdns3: Fix for CV CH9 running with g_zero driver. usb: dwc3: Remove dev_err() on platform_get_irq() failure usb: dwc3: Switch to platform_get_irq_byname_optional() ...
2019-10-12Merge tag 'for-linus-5.4-rc3-tag' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip Pull xen fixes from Juergen Gross: - correct panic handling when running as a Xen guest - cleanup the Xen grant driver to remove printing a pointer being always NULL - remove a soon to be wrong call of of_dma_configure() * tag 'for-linus-5.4-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: xen: Stop abusing DT of_dma_configure API xen/grant-table: remove unnecessary printing x86/xen: Return from panic notifier
2019-10-11Merge tag 'modules-for-v5.4-rc3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux Pull module fixes from Jessica Yu: "Code cleanups and kbuild/namespace related fixups from Masahiro. Most importantly, it fixes a namespace-related modpost issue for external module builds - Fix broken external module builds due to a modpost bug in read_dump(), where the namespace was not being strdup'd and sym->namespace would be set to bogus data. - Various namespace-related kbuild fixes and cleanups thanks to Masahiro Yamada" * tag 'modules-for-v5.4-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux: doc: move namespaces.rst from kbuild/ to core-api/ nsdeps: make generated patches independent of locale nsdeps: fix hashbang of scripts/nsdeps kbuild: fix build error of 'make nsdeps' in clean tree module: rename __kstrtab_ns_* to __kstrtabns_* to avoid symbol conflict modpost: fix broken sym->namespace for external module builds module: swap the order of symbol.namespace scripts: add_namespace: Fix coccicheck failed
2019-10-11Documentation/process: Add fallthrough pseudo-keywordJoe Perches
Describe the fallthrough pseudo-keyword. Convert the coding-style.rst example to the keyword style. Add description and links to deprecated.rst. Miguel Ojeda comments on the eventual [[fallthrough]] syntax: "Note that C17/C18 does not have [[fallthrough]]. C++17 introduced it, as it is mentioned above. I would keep the __attribute__((fallthrough)) -> [[fallthrough]] change you did, though, since that is indeed the standard syntax (given the paragraph references C++17). I was told by Aaron Ballman (who is proposing them for C) that it is more or less likely that it becomes standardized in C2x. However, it is still not added to the draft (other attributes are already, though). See N2268 and N2269: http://www.open-std.org/jtc1/sc22/wg14/www/docs/n2268.pdf (fallthrough) http://www.open-std.org/jtc1/sc22/wg14/www/docs/n2269.pdf (attributes in general)" Signed-off-by: Joe Perches <joe@perches.com> Acked-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-10-11dt-bindings: display: rockchip: document VOP gamma LUT addressEzequiel Garcia
Add the register specifier description for an optional gamma LUT address. Reviewed-by: Douglas Anderson <dianders@chromium.org> Reviewed-by: Rob Herring <robh@kernel.org> Tested-by: Heiko Stuebner <heiko@sntech.de> Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com> Signed-off-by: Sean Paul <seanpaul@chromium.org> Link: https://patchwork.freedesktop.org/patch/msgid/20191010194351.17940-2-ezequiel@collabora.com
2019-10-10net: update net_dim documentation after renameJacob Keller
Commit 8960b38932be ("linux/dim: Rename externally used net_dim members") renamed the net_dim API, removing the "net_" prefix from the structures and functions. The patch didn't update the net_dim.txt documentation file. Fix the documentation so that its examples match the current code. Fixes: 8960b38932be ("linux/dim: Rename externally used net_dim members", 2019-06-25) Fixes: c002bd529d71 ("linux/dim: Rename externally exposed macros", 2019-06-25) Fixes: 4f75da3666c0 ("linux/dim: Move implementation to .c files") Cc: Tal Gilboa <talgi@mellanox.com> Signed-off-by: Jacob Keller <jacob.e.keller@intel.com> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-10-11Merge tag 'drm-misc-next-2019-10-09-2' of ↵Dave Airlie
git://anongit.freedesktop.org/drm/drm-misc into drm-next drm-misc-next for 5.5: UAPI Changes: -Colorspace: Expose different prop values for DP vs. HDMI (Gwan-gyeong Mun) -fourcc: Add DRM_FORMAT_MOD_ARM_16X16_BLOCK_U_INTERLEAVED (Raymond) -not_actually: s/ENOTSUPP/EOPNOTSUPP/ in drm_edid and drm_mipi_dbi. This should not reach userspace, but adding here to specifically call that out (Daniel) -i810: Prevent underflow in dispatch ioctls (Dan) -komeda: Add ACLK sysfs attribute (Mihail) -v3d: Allow userspace to clean up after render jobs (Iago) Cross-subsystem Changes: -MAINTAINERS: -Add Alyssa & Steven as panfrost reviewers (Rob) -Add Jernej as DE2 reviewer (Maxime) -Add Chen-Yu as Allwinner maintainer (Maxime) -staging: Make some stack arrays static const (Colin) Core Changes: -ttm: Allow drivers to specify their vma manager (to use gem mgr) (Gerd) -docs: Various fixes in connector/encoder/bridge docs (Daniel, Lyude, Laurent) -connector: Allow more than 3 possible encoders for a connector (José) -dp_cec: Allow a connector to be associated with a cec device (Dariusz) -various: Fix some compile/sparse warnings (Ville) -mm: Ensure mm node removals are properly serialised (Chris) -panel: Specify the type of panel for drm_panels for later use (Laurent) -panel: Use drm_panel_init to init device and funcs (Laurent) -mst: Refactors and cleanups in anticipation of suspend/resume support (Lyude) -vram: -Add lazy unmapping for gem bo's (Thomas) -Unify and rationalize vram mm and gem vram (Thomas) -Expose vmap and vunmap for gem vram objects (Thomas) -Allow objects to be pinned at the top of vram to avoid fragmentation (Thomas) Driver Changes: -various: Include drm_bridge.h instead of relying on drm_crtc.h (Boris) -ast/mgag200: Refactor show_cursor(), move cursor to top of video mem (Thomas) -komeda: -Add error event printing (behind CONFIG) and reg dump support (Lowry) -Add suspend/resume support (Lowry) -Workaround D71 shadow registers not flushing on disable (Lowry) -meson: Add suspend/resume support (Neil) -omap: Miscellaneous refactors and improvements (Tomi/Jyri) -panfrost/shmem: Silence lockdep by using mutex_trylock (Rob) -panfrost: Miscellaneous small fixes (Rob/Steven) -sti: Fix warnings (Benjamin/Linus) -sun4i: -Add vcc-dsi regulator to sun6i_mipi_dsi (Jagan) -A few patches to figure out the DRQ/start delay calc on dsi (Jagan/Icenowy) -virtio: -Add module param to switch resource reuse workaround on/off (Gerd) -Avoid calling vmexit while holding spinlock (Gerd) -Use gem shmem helpers instead of ttm (Gerd) -Accommodate command buffer allocations too big for cma (David) Cc: Rob Herring <robh@kernel.org> Cc: Maxime Ripard <mripard@kernel.org> Cc: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com> Cc: Gerd Hoffmann <kraxel@redhat.com> Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Cc: Lyude Paul <lyude@redhat.com> Cc: José Roberto de Souza <jose.souza@intel.com> Cc: Dariusz Marcinkiewicz <darekm@google.com> Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Raymond Smith <raymond.smith@arm.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Colin Ian King <colin.king@canonical.com> Cc: Thomas Zimmermann <tzimmermann@suse.de> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: Mihail Atanassov <Mihail.Atanassov@arm.com> Cc: Lowry Li <Lowry.Li@arm.com> Cc: Neil Armstrong <narmstrong@baylibre.com> Cc: Jyri Sarha <jsarha@ti.com> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> Cc: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com> Cc: Steven Price <steven.price@arm.com> Cc: Benjamin Gaignard <benjamin.gaignard@st.com> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Jagan Teki <jagan@amarulasolutions.com> Cc: Icenowy Zheng <icenowy@aosc.io> Cc: Iago Toral Quiroga <itoral@igalia.com> Cc: David Riley <davidriley@chromium.org> Signed-off-by: Dave Airlie <airlied@redhat.com> # gpg: Signature made Thu 10 Oct 2019 01:00:47 AM AEST # gpg: using RSA key 732C002572DCAF79 # gpg: Can't check signature: public key not found # Conflicts: # drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c # drivers/gpu/drm/i915/i915_drv.c # drivers/gpu/drm/i915/i915_gem.c # drivers/gpu/drm/i915/i915_gem_gtt.c # drivers/gpu/drm/i915/i915_vma.c From: Sean Paul <sean@poorly.run> Link: https://patchwork.freedesktop.org/patch/msgid/20191009150825.GA227673@art_vandelay
2019-10-09Documentation: Fix warning in drm-kms-helpers.rstSean Paul
Fixes the following warning: ../include/drm/drm_atomic_state_helper.h:1: warning: no structured comments found Fixes: 9ef8a9dc4b21 ("drm: Extract drm_atomic_state_helper.[hc]") Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Daniel Vetter <daniel.vetter@intel.com> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Maxime Ripard <mripard@kernel.org> Cc: Sean Paul <sean@poorly.run> Cc: David Airlie <airlied@linux.ie> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: dri-devel@lists.freedesktop.org Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Sean Paul <seanpaul@chromium.org> Link: https://patchwork.freedesktop.org/patch/msgid/20191007151921.27099-1-sean@poorly.run
2019-10-09Merge tag 'arm64-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 fixes from Will Deacon: "A larger-than-usual batch of arm64 fixes for -rc3. The bulk of the fixes are dealing with a bunch of issues with the build system from the compat vDSO, which unfortunately led to some significant Makefile rework to manage the horrible combinations of toolchains that we can end up needing to drive simultaneously. We came close to disabling the thing entirely, but Vincenzo was quick to spin up some patches and I ended up picking up most of the bits that were left [*]. Future work will look at disentangling the header files properly. Other than that, we have some important fixes all over, including one papering over the miscompilation fallout from forcing CONFIG_OPTIMIZE_INLINING=y, which I'm still unhappy about. Harumph. We've still got a couple of open issues, so I'm expecting to have some more fixes later this cycle. Summary: - Numerous fixes to the compat vDSO build system, especially when combining gcc and clang - Fix parsing of PAR_EL1 in spurious kernel fault detection - Partial workaround for Neoverse-N1 erratum #1542419 - Fix IRQ priority masking on entry from compat syscalls - Fix advertisment of FRINT HWCAP to userspace - Attempt to workaround inlining breakage with '__always_inline' - Fix accidental freeing of parent SVE state on fork() error path - Add some missing NULL pointer checks in instruction emulation init - Some formatting and comment fixes" [*] Will's final fixes were Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com> but they were already in linux-next by then and he didn't rebase just to add those. * tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (21 commits) arm64: armv8_deprecated: Checking return value for memory allocation arm64: Kconfig: Make CONFIG_COMPAT_VDSO a proper Kconfig option arm64: vdso32: Rename COMPATCC to CC_COMPAT arm64: vdso32: Pass '--target' option to clang via VDSO_CAFLAGS arm64: vdso32: Don't use KBUILD_CPPFLAGS unconditionally arm64: vdso32: Move definition of COMPATCC into vdso32/Makefile arm64: Default to building compat vDSO with clang when CONFIG_CC_IS_CLANG lib: vdso: Remove CROSS_COMPILE_COMPAT_VDSO arm64: vdso32: Remove jump label config option in Makefile arm64: vdso32: Detect binutils support for dmb ishld arm64: vdso: Remove stale files from old assembly implementation arm64: vdso32: Fix broken compat vDSO build warnings arm64: mm: fix spurious fault detection arm64: ftrace: Ensure synchronisation in PLT setup for Neoverse-N1 #1542419 arm64: Fix incorrect irqflag restore for priority masking for compat arm64: mm: avoid virt_to_phys(init_mm.pgd) arm64: cpufeature: Effectively expose FRINT capability to userspace arm64: Mark functions using explicit register variables as '__always_inline' docs: arm64: Fix indentation and doc formatting arm64/sve: Fix wrong free for task->thread.sve_state ...
2019-10-08Doc: networking/device_drivers/pensando: fix ionic.rst warningsRandy Dunlap
Fix documentation build warnings for Pensando ionic: Documentation/networking/device_drivers/pensando/ionic.rst:39: WARNING: Unexpected indentation. Documentation/networking/device_drivers/pensando/ionic.rst:43: WARNING: Unexpected indentation. Fixes: df69ba43217d ("ionic: Add basic framework for IONIC Network device driver") Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Shannon Nelson <snelson@pensando.io> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
2019-10-08Merge tag 'linux-kselftest-5.4-rc3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest Pull Kselftest fixes from Shuah Khan: "Fixes for existing tests and the framework. Cristian Marussi's patches add the ability to skip targets (tests) and exclude tests that didn't build from run-list. These patches improve the Kselftest results. Ability to skip targets helps avoid running tests that aren't supported in certain environments. As an example, bpf tests from mainline aren't supported on stable kernels and have dependency on bleeding edge llvm. Being able to skip bpf on systems that can't meet this llvm dependency will be helpful. Kselftest can be built and installed from the main Makefile. This change help simplify Kselftest use-cases which addresses request from users. Kees Cook added per test timeout support to limit individual test run-time" * tag 'linux-kselftest-5.4-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: selftests: watchdog: Add command line option to show watchdog_info selftests: watchdog: Validate optional file argument selftests/kselftest/runner.sh: Add 45 second timeout per test kselftest: exclude failed TARGETS from runlist kselftest: add capability to skip chosen TARGETS selftests: Add kselftest-all and kselftest-install targets
2019-10-08drm: delete drmP.h + drm_os_linux.hSam Ravnborg
There is finally no more users left in the kernel of drmP.h and drm_os_linux.h (drmP.h was the only user left). Delete the header files and delete the corresponding todo entry. When we started this quest there was more than 700 users of drmP.h. And drmP.h was a huge cover-it-all header file. Daniel Vetter is the one that followed the work from start to the end and in between many people have contributed to the removal process - thanks to everyone! Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Reviewed-by: Sean Paul <sean@poorly.run> Reviewed-by: Lyude Paul <lyude@redhat.com> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Maxime Ripard <mripard@kernel.org> Cc: Sean Paul <sean@poorly.run> Cc: David Airlie <airlied@linux.ie> Cc: Daniel Vetter <daniel@ffwll.ch> Link: https://patchwork.freedesktop.org/patch/msgid/20191007171224.1581-3-sam@ravnborg.org
2019-10-08doc: move namespaces.rst from kbuild/ to core-api/Masahiro Yamada
We discussed a better location for this file, and agreed that core-api/ is a good fit. Rename it to symbol-namespaces.rst for disambiguation, and also add it to index.rst and MAINTAINERS. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Acked-by: Matthias Maennich <maennich@google.com> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2019-10-08arm64: Allow CAVIUM_TX2_ERRATUM_219 to be selectedMarc Zyngier
Allow the user to select the workaround for TX2-219, and update the silicon-errata.rst file to reflect this. Cc: <stable@vger.kernel.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will@kernel.org>
2019-10-08Merge tag 'drm-intel-next-2019-10-07' of ↵Dave Airlie
git://anongit.freedesktop.org/drm/drm-intel into drm-next UAPI Changes: - Never allow userptr into the mappable GGTT (Chris) No existing users. Avoid anyone from even trying to spare a deadlock scenario. Cross-subsystem Changes: Core Changes: Driver Changes: - Eliminate struct_mutex use as BKL! (Chris) Only used for execbuf serialisation. - Initialize DDI TC and TBT ports (D-I) on Tigerlake (Lucas) - Fix DKL link training for 2.7GHz and 1.62GHz (Jose) - Add Tigerlake DKL PHY programming sequences (Clinton) - Add Tigerlake Thunderbolt PLL divider values (Imre) - drm/i915: Use helpers for drm_mm_node booleans (Chris) - Restrict L3 remapping sysfs interface to dwords (Chris) - Fix audio power up sequence for gen10+ display (Kai) - Skip redundant execlist resubmission (Chris) - Only unwedge if we can reset GPU first (Chris) - Initialise breadcrumb lists on the virtual engine (Chris) - Don't rely on kernel context existing during early errors (Matt A) - Update Icelake+ MG_DP_MODE programming table (Clinton) - Update DMC firmware for Icelake (Anusha) - Downgrade DP MST error after unplugging TypeC cable (Srinivasan) - Limit MST modes based on plane size too (Ville) - Polish intel_tv_mode_valid() (Ville) - Fix g4x sprite scaling stride check with GTT remapping (Ville) - Don't advertize non-exisiting crtcs (Ville) - Clean up encoder->crtc_mask setup (Ville) - Use tc_port instead of port parameter to MG registers (Jose) - Remove static variable for aux last status (Jani) - Implement a better i945gm vblank irq vs. C-states workaround (Ville) - Make the object creation interface consistent (CQ) - Rename intel_vga_msr_write() to intel_vga_reset_io_mem() (Jani, Ville) - Eliminate previous drm_dbg/drm_err usage (Jani) - Move gmbus setup down to intel_modeset_init() (Jani) - Abstract all vgaarb access to intel_vga.[ch] (Jani) - Split out i915_switcheroo.[ch] from i915_drv.c (Jani) - Use intel_gt in has_reset* (Chris) - Eliminate return value for i915_gem_init_early (Matt A) - Selftest improvements (Chris) - Update HuC firmware header version number format (Daniele) Signed-off-by: Dave Airlie <airlied@redhat.com> From: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20191007134801.GA24313@jlahtine-desk.ger.corp.intel.com
2019-10-07Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge misc fixes from Andrew Morton: "The usual shower of hotfixes. Chris's memcg patches aren't actually fixes - they're mature but a few niggling review issues were late to arrive. The ocfs2 fixes are quite old - those took some time to get reviewer attention. Subsystems affected by this patch series: ocfs2, hotfixes, mm/memcg, mm/slab-generic" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: mm, sl[aou]b: guarantee natural alignment for kmalloc(power-of-two) mm, sl[ou]b: improve memory accounting mm, memcg: make scan aggression always exclude protection mm, memcg: make memory.emin the baseline for utilisation determination mm, memcg: proportional memory.{low,min} reclaim mm/vmpressure.c: fix a signedness bug in vmpressure_register_event() mm/page_alloc.c: fix a crash in free_pages_prepare() mm/z3fold.c: claim page in the beginning of free kernel/sysctl.c: do not override max_threads provided by userspace memcg: only record foreign writebacks with dirty pages when memcg is not disabled mm: fix -Wmissing-prototypes warnings writeback: fix use-after-free in finish_writeback_work() mm/memremap: drop unused SECTION_SIZE and SECTION_MASK panic: ensure preemption is disabled during panic() fs: ocfs2: fix a possible null-pointer dereference in ocfs2_info_scan_inode_alloc() fs: ocfs2: fix a possible null-pointer dereference in ocfs2_write_end_nolock() fs: ocfs2: fix possible null-pointer dereferences in ocfs2_xa_prepare_entry() ocfs2: clear zero in unaligned direct IO
2019-10-07mm, sl[aou]b: guarantee natural alignment for kmalloc(power-of-two)Vlastimil Babka
In most configurations, kmalloc() happens to return naturally aligned (i.e. aligned to the block size itself) blocks for power of two sizes. That means some kmalloc() users might unknowingly rely on that alignment, until stuff breaks when the kernel is built with e.g. CONFIG_SLUB_DEBUG or CONFIG_SLOB, and blocks stop being aligned. Then developers have to devise workaround such as own kmem caches with specified alignment [1], which is not always practical, as recently evidenced in [2]. The topic has been discussed at LSF/MM 2019 [3]. Adding a 'kmalloc_aligned()' variant would not help with code unknowingly relying on the implicit alignment. For slab implementations it would either require creating more kmalloc caches, or allocate a larger size and only give back part of it. That would be wasteful, especially with a generic alignment parameter (in contrast with a fixed alignment to size). Ideally we should provide to mm users what they need without difficult workarounds or own reimplementations, so let's make the kmalloc() alignment to size explicitly guaranteed for power-of-two sizes under all configurations. What this means for the three available allocators? * SLAB object layout happens to be mostly unchanged by the patch. The implicitly provided alignment could be compromised with CONFIG_DEBUG_SLAB due to redzoning, however SLAB disables redzoning for caches with alignment larger than unsigned long long. Practically on at least x86 this includes kmalloc caches as they use cache line alignment, which is larger than that. Still, this patch ensures alignment on all arches and cache sizes. * SLUB layout is also unchanged unless redzoning is enabled through CONFIG_SLUB_DEBUG and boot parameter for the particular kmalloc cache. With this patch, explicit alignment is guaranteed with redzoning as well. This will result in more memory being wasted, but that should be acceptable in a debugging scenario. * SLOB has no implicit alignment so this patch adds it explicitly for kmalloc(). The potential downside is increased fragmentation. While pathological allocation scenarios are certainly possible, in my testing, after booting a x86_64 kernel+userspace with virtme, around 16MB memory was consumed by slab pages both before and after the patch, with difference in the noise. [1] https://lore.kernel.org/linux-btrfs/c3157c8e8e0e7588312b40c853f65c02fe6c957a.1566399731.git.christophe.leroy@c-s.fr/ [2] https://lore.kernel.org/linux-fsdevel/20190225040904.5557-1-ming.lei@redhat.com/ [3] https://lwn.net/Articles/787740/ [akpm@linux-foundation.org: documentation fixlet, per Matthew] Link: http://lkml.kernel.org/r/20190826111627.7505-3-vbabka@suse.cz Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Christoph Hellwig <hch@lst.de> Cc: David Sterba <dsterba@suse.cz> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Ming Lei <ming.lei@redhat.com> Cc: Dave Chinner <david@fromorbit.com> Cc: "Darrick J . Wong" <darrick.wong@oracle.com> Cc: Christoph Hellwig <hch@lst.de> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-10-07mm, memcg: proportional memory.{low,min} reclaimChris Down
cgroup v2 introduces two memory protection thresholds: memory.low (best-effort) and memory.min (hard protection). While they generally do what they say on the tin, there is a limitation in their implementation that makes them difficult to use effectively: that cliff behaviour often manifests when they become eligible for reclaim. This patch implements more intuitive and usable behaviour, where we gradually mount more reclaim pressure as cgroups further and further exceed their protection thresholds. This cliff edge behaviour happens because we only choose whether or not to reclaim based on whether the memcg is within its protection limits (see the use of mem_cgroup_protected in shrink_node), but we don't vary our reclaim behaviour based on this information. Imagine the following timeline, with the numbers the lruvec size in this zone: 1. memory.low=1000000, memory.current=999999. 0 pages may be scanned. 2. memory.low=1000000, memory.current=1000000. 0 pages may be scanned. 3. memory.low=1000000, memory.current=1000001. 1000001* pages may be scanned. (?!) * Of course, we won't usually scan all available pages in the zone even without this patch because of scan control priority, over-reclaim protection, etc. However, as shown by the tests at the end, these techniques don't sufficiently throttle such an extreme change in input, so cliff-like behaviour isn't really averted by their existence alone. Here's an example of how this plays out in practice. At Facebook, we are trying to protect various workloads from "system" software, like configuration management tools, metric collectors, etc (see this[0] case study). In order to find a suitable memory.low value, we start by determining the expected memory range within which the workload will be comfortable operating. This isn't an exact science -- memory usage deemed "comfortable" will vary over time due to user behaviour, differences in composition of work, etc, etc. As such we need to ballpark memory.low, but doing this is currently problematic: 1. If we end up setting it too low for the workload, it won't have *any* effect (see discussion above). The group will receive the full weight of reclaim and won't have any priority while competing with the less important system software, as if we had no memory.low configured at all. 2. Because of this behaviour, we end up erring on the side of setting it too high, such that the comfort range is reliably covered. However, protected memory is completely unavailable to the rest of the system, so we might cause undue memory and IO pressure there when we *know* we have some elasticity in the workload. 3. Even if we get the value totally right, smack in the middle of the comfort zone, we get extreme jumps between no pressure and full pressure that cause unpredictable pressure spikes in the workload due to the current binary reclaim behaviour. With this patch, we can set it to our ballpark estimation without too much worry. Any undesirable behaviour, such as too much or too little reclaim pressure on the workload or system will be proportional to how far our estimation is off. This means we can set memory.low much more conservatively and thus waste less resources *without* the risk of the workload falling off a cliff if we overshoot. As a more abstract technical description, this unintuitive behaviour results in having to give high-priority workloads a large protection buffer on top of their expected usage to function reliably, as otherwise we have abrupt periods of dramatically increased memory pressure which hamper performance. Having to set these thresholds so high wastes resources and generally works against the principle of work conservation. In addition, having proportional memory reclaim behaviour has other benefits. Most notably, before this patch it's basically mandatory to set memory.low to a higher than desirable value because otherwise as soon as you exceed memory.low, all protection is lost, and all pages are eligible to scan again. By contrast, having a gradual ramp in reclaim pressure means that you now still get some protection when thresholds are exceeded, which means that one can now be more comfortable setting memory.low to lower values without worrying that all protection will be lost. This is important because workingset size is really hard to know exactly, especially with variable workloads, so at least getting *some* protection if your workingset size grows larger than you expect increases user confidence in setting memory.low without a huge buffer on top being needed. Thanks a lot to Johannes Weiner and Tejun Heo for their advice and assistance in thinking about how to make this work better. In testing these changes, I intended to verify that: 1. Changes in page scanning become gradual and proportional instead of binary. To test this, I experimented stepping further and further down memory.low protection on a workload that floats around 19G workingset when under memory.low protection, watching page scan rates for the workload cgroup: +------------+-----------------+--------------------+--------------+ | memory.low | test (pgscan/s) | control (pgscan/s) | % of control | +------------+-----------------+--------------------+--------------+ | 21G | 0 | 0 | N/A | | 17G | 867 | 3799 | 23% | | 12G | 1203 | 3543 | 34% | | 8G | 2534 | 3979 | 64% | | 4G | 3980 | 4147 | 96% | | 0 | 3799 | 3980 | 95% | +------------+-----------------+--------------------+--------------+ As you can see, the test kernel (with a kernel containing this patch) ramps up page scanning significantly more gradually than the control kernel (without this patch). 2. More gradual ramp up in reclaim aggression doesn't result in premature OOMs. To test this, I wrote a script that slowly increments the number of pages held by stress(1)'s --vm-keep mode until a production system entered severe overall memory contention. This script runs in a highly protected slice taking up the majority of available system memory. Watching vmstat revealed that page scanning continued essentially nominally between test and control, without causing forward reclaim progress to become arrested. [0]: https://facebookmicrosites.github.io/cgroup2/docs/overview.html#case-study-the-fbtax2-project [akpm@linux-foundation.org: reflow block comments to fit in 80 cols] [chris@chrisdown.name: handle cgroup_disable=memory when getting memcg protection] Link: http://lkml.kernel.org/r/20190201045711.GA18302@chrisdown.name Link: http://lkml.kernel.org/r/20190124014455.GA6396@chrisdown.name Signed-off-by: Chris Down <chris@chrisdown.name> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Roman Gushchin <guro@fb.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Tejun Heo <tj@kernel.org> Cc: Dennis Zhou <dennis@kernel.org> Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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