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* ALSA: hda - fix use-after-free after module unloadPeter Wu2016-07-111-1/+3
| | | | | | | | | | | | register_vga_switcheroo() sets the PM ops from the hda structure which is freed later in azx_free. Make sure that these ops are cleared. Caught by KASAN, initially noticed due to a general protection fault. Fixes: 246efa4a072f ("snd/hda: add runtime suspend/resume on optimus support (v4)") Signed-off-by: Peter Wu <peter@lekensteyn.nl> Cc: <stable@vger.kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: pcm: Free chmap at PCM free callback, tooTakashi Iwai2016-07-081-4/+10
| | | | | | | | | | | | | | | | | The chmap ctls assigned to PCM streams are freed in the PCM disconnect callback. However, since the disconnect callback isn't called when the card gets freed before registering, the chmap ctls may still be left assigned. They are eventually freed together with other ctls, but it may cause an Oops at pcm_chmap_ctl_private_free(), as the function refers to the assigned PCM stream, while the PCM objects have been already freed beforehand. The fix is to free the chmap ctls also at PCM free callback, not only at PCM disconnect. Reported-by: Laxminath Kasam <b_lkasam@codeaurora.org> Cc: <stable@vger.kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: ctl: Stop notification after disconnectionTakashi Iwai2016-07-081-0/+2
| | | | | | | | | | | | | | | snd_ctl_remove() has a notification for the removal event. It's superfluous when done during the device got disconnected. Although the notification itself is mostly harmless, it may potentially be harmful, and should be suppressed. Actually some components PCM may free ctl elements during the disconnect or free callbacks, thus it's no theoretical issue. This patch adds the check of card->shutdown flag for avoiding unnecessary notifications after (or during) the disconnect. Cc: <stable@vger.kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: hda/realtek - add new pin definition in alc225 pin quirk tableHui Wang2016-07-081-1/+14
| | | | | | | | | | We have some Dell laptops which can't detect headset mic, the machines use the codec ALC225, they have some new pin configuration values, after adding them in the alc225 pin quirk table, they work well. Cc: <stable@vger.kernel.org> Signed-off-by: Hui Wang <hui.wang@canonical.com> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: hda/realtek: Add Lenovo L460 to docking unit fixupTorsten Hilbrich2016-07-051-0/+1
| | | | | | | | | This solves the issue that a headphone is not working on the docking unit. Signed-off-by: Torsten Hilbrich <torsten.hilbrich@secunet.com> Cc: <stable@vger.kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* ALSA: timer: Fix negative queue usage by racy accessesTakashi Iwai2016-07-041-1/+1
| | | | | | | | | | | | | | The user timer tu->qused counter may go to a negative value when multiple concurrent reads are performed since both the check and the decrement of tu->qused are done in two individual locked contexts. This results in bogus read outs, and the endless loop in the user-space side. The fix is to move the decrement of the tu->qused counter into the same spinlock context as the zero-check of the counter. Cc: <stable@vger.kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>
* Merge tag 'asoc-fix-v4.7-rc5' of ↵Takashi Iwai2016-07-02992-5881/+9521
|\ | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus ASoC: Fixes for v4.7 A small clutch of hardware specific fixes for various ASoC devices, all small individually and important if you have that device but not otherwise.
| *---. Merge remote-tracking branches 'asoc/fix/rcar', 'asoc/fix/rt5670' and ↵Mark Brown2016-07-013-2/+3
| |\ \ \ | | | | | | | | | | | | | | | 'asoc/fix/wm8940' into asoc-linus
| | | | * ASoC: wm8940: Enable cache usage to fix crashes on resumeGeert Uytterhoeven2016-06-171-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The wm8940 driver is using a regmap cache sync to restore the configuration of the chip when switching from OFF to STANDBY, but does not actually define a register cache which means that the restore is never going to work and we trigger asserts in regmap. Fix this by enabling caching. Based on commit d3030d11961a8c10 ("ASoC: ak4642: Enable cache usage to fix crashes on resume") by Mark Brown <broonie@kernel.org>. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@kernel.org>
| | | * | ASoC: rt5670: fix HP Playback Volume controlBard Liao2016-06-071-1/+1
| | | |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | The register setting for HP Playback Volume is inverted. So, set the invert flag in SOC_DOUBLE_TLV. Signed-off-by: Bard Liao <bardliao@realtek.com> Signed-off-by: Mark Brown <broonie@kernel.org>
| | * | ASoC: rsnd: open 31bit of SSICKR maskKuninori Morimoto2016-05-271-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | SSICKR (Gen2) / BRGCKR (Gen3) 31bit mask should be opened, because BRGB (= for 48kHz) might select it. Special thanks Yokoyama-san Reported-by: Hiroyuki Yokoyama <hiroyuki.yokoyama.vx@renesas.com> Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com> Signed-off-by: Mark Brown <broonie@kernel.org>
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| *---------. \ \ Merge remote-tracking branches 'asoc/fix/ak4613', 'asoc/fix/arizona', ↵Mark Brown2016-07-018-17/+68
| |\ \ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 'asoc/fix/cx20442', 'asoc/fix/davinci', 'asoc/fix/fsl-ssi' and 'asoc/fix/hdmi' into asoc-linus
| | | | | | | * | | ASoC: hdmi-codec: select CONFIG_HDMIArnd Bergmann2016-06-021-3/+4
| | | | | | | | |/ | | | | | | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | SND_SOC_HDMI_CODEC can be enabled without HDMI support, leading to a link error: In function `hdmi_codec_hw_params': sound/soc/codecs/hdmi-codec.c:188: undefined reference to `hdmi_audio_infoframe_init' sound/built-in.o:(.debug_addr+0x1a5c0): undefined reference to `hdmi_audio_infoframe_init' This changes the Kconfig file to select HDMI, as the other codec using hdmi_audio_infoframe_init already does. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Jyri Sarha <jsarha@ti.com> Signed-off-by: Mark Brown <broonie@kernel.org>
| | | | | | * / | ASoC: fsl_ssi: Fix number of words per frame for I2S-slave modeAlexander Shiyan2016-06-291-6/+6
| | | | | | |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The i.MX51 datasheet says: Chapter 56.1.2.4 I2S Mode ... When I2S modes are entered (I2S master (01) or I2S slave (10)), the following settings are recommended: ... - TX Frame Rate should be 2 i.e. (STCCR[12:8] = 1) - RX Frame Rate should be 2 i.e. (SRCCR[12:8] = 1) Chapter 56.3.3.12 SSI Transmit and Receive Clock Control Registers (STCCR & SRCCR) ... Bits 12-8 DC4-DC0 Frame Rate Divider Control. These bits are used to control the divide ratio for the programmable frame rate dividers. The divide ratio works on the word clock. In Normal mode, this ratio determines the word transfer rate. In Network mode, this ratio sets the number of words per frame. The divide ratio ranges from 1 to 32 in Normal mode and from 2 to 32 in Network mode. In Normal mode, a divide ratio of 1 (DC=00000) provides continuous periodic data word transfer. A bit-length frame sync must be used in this case. Function fsl_ssi_hw_params() setup Normal mode for MONO output, so with DC=0, SSI enters to continuous periodic data word transfer. To fix this, setup DC for any I2S mode. Patch has tested on custom board based on Digi CCMX-51 module (i.MX51). Signed-off-by: Alexander Shiyan <shc_work@mail.ru> Signed-off-by: Mark Brown <broonie@kernel.org>
| | | | | * / / ASoC: davinci-mcasp: Fix dra7 DMA offset when using CFG portPeter Ujfalusi2016-06-022-6/+54
| | | | | |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The TX and RX offset is different for each serializers when using the CFG port for DMA access. When using the CFG port only one serializer can be used per direction so print error message and only configure the first serializer's offset. Reported-by: Misael Lopez Cruz <misael.lopez@ti.com> Suggested-by: Misael Lopez Cruz <misael.lopez@ti.com> Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com> Signed-off-by: Mark Brown <broonie@kernel.org>
| | | | * / / ASoC: cx20442: set tty->receiver_room in v253_openJanusz Krzysztofik2016-06-171-0/+1
| | | | |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 79901317ce80 ("n_tty: Don't flush buffer when closing ldisc"), introduced in v3.10, revealed a bug in the cx20442 codec driver which has never been setting tty->receive_room on line discipline open as it should from the beginning. Fix it. Created and tested on Amstrad Delta against Linux-4.7-rc3 Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com> Signed-off-by: Mark Brown <broonie@kernel.org>
| | | * | | ASoC: wm5102: Correct supported channels on trace compressed DAICharles Keepax2016-06-131-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The audio trace firmware on wm5102 only supports 4 channels correct the DAI driver structure to reflect this. Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@kernel.org>
| | | * | | ASoC: wm5110: Add missing route from OUT3R to SYSCLKAjit Pandey2016-06-131-0/+1
| | | |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Output 3 is stereo on wm5110 and all inputs/outputs should have a connection to SYSCLK. This patch adds the missing DAPM route. Signed-off-by: Ajit Pandey <ajit.pandey@soctronics.com> Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com> Signed-off-by: Mark Brown <broonie@kernel.org>
| | * | | ASoC: ak4613: Enable cache usage to fix crashes on resumeGeert Uytterhoeven2016-06-171-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | During system resume: kernel BUG at drivers/base/regmap/regcache.c:347! ... PC is at regcache_sync+0x1c/0x128 LR is at ak4613_resume+0x28/0x34 The ak4613 driver is using a regmap cache sync to restore the configuration of the chip on resume but does not actually define a register cache which means that the resume is never going to work and we trigger asserts in regmap. Fix this by enabling caching. Based on commit d3030d11961a8c10 ("ASoC: ak4642: Enable cache usage to fix crashes on resume") by Mark Brown <broonie@kernel.org>. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Mark Brown <broonie@kernel.org>
| | * | | ASoC: ak4613: Remove owner assignment from platform_driverFabio Estevam2016-05-301-1/+0
| | |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This platform_driver does not need to set an owner as it will be populated by the driver core. Generated by scripts/coccinelle/api/platform_no_drv_owner.cocci. Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com> Signed-off-by: Mark Brown <broonie@kernel.org>
| * | | Merge remote-tracking branch 'asoc/fix/rt5645' into asoc-linusMark Brown2016-07-011-1/+1
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| | * | | ASoC: rt5645: fix reg-2f default value.Bard Liao2016-07-011-1/+1
| | |/ / | | | | | | | | | | | | | | | | | | | | | | | | The default value of reg-2f in codec rt5650 is 0x5002, not 0x1002. Signed-off-by: Bard Liao <bardliao@realtek.com> Signed-off-by: Mark Brown <broonie@kernel.org>
| * | | Merge remote-tracking branch 'asoc/fix/intel' into asoc-linusMark Brown2016-07-013-2/+28
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| | * | | ASoC: Intel: atom: fix missing breaks that would cause the wrong operation ↵Alan Cox2016-06-261-2/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | to execute Now we correctly error an attempt to execute an unsupported operation. Signed-off-by: Alan Cox <alan@linux.intel.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com> Signed-off-by: Mark Brown <broonie@kernel.org>
| | * | | ASoC: Intel: Skylake: Initialize module list for BroxtonVinod Koul2016-06-141-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The module list was not initialized for Broxton DSP code, so initialize it. Signed-off-by: Vinod Koul <vinod.koul@intel.com> Signed-off-by: Mark Brown <broonie@kernel.org>
| | * | | ASoC: hdac_hdmi: Fix potential NULL dereferenceVinod Koul2016-05-311-0/+20
| | |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Static checker warns: Pointer 'hlink' returned from call to function 'snd_hdac_ext_bus_get_link' at line may be NULL and will be dereferenced" So we should always check the return of snd_hdac_ext_bus_get_link() before referencing the link pointer Signed-off-by: Vinod Koul <vinod.koul@intel.com> Signed-off-by: Mark Brown <broonie@kernel.org>
| * | | Linux 4.7-rc5v4.7-rc5Linus Torvalds2016-06-271-1/+1
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| * | | Merge tag 'scsi-fixes' of ↵Linus Torvalds2016-06-264-6/+12
| |\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi Pull SCSI fixes from James Bottomley: "Two straightforward fixes. One is a concurrency issue only affecting SAS connected SATA drives, but which could hang the storage subsystem if it triggers (because the outstanding command count on error never goes back to zero) and the other is a NO_TAG fallout from the switch to hostwide tags which causes the system to crash on module insertion (we've checked carefully and only the 53c700 family of drivers is vulnerable to this issue)" * tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: 53c700: fix BUG on untagged commands scsi: fix race between simultaneous decrements of ->host_failed
| | * \ \ Merge remote-tracking branch 'mkp-scsi/4.7/scsi-fixes' into fixesJames Bottomley2016-06-184-6/+12
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| | | * | | 53c700: fix BUG on untagged commandsJames Bottomley2016-06-151-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The untagged command case in the 53c700 driver has been broken since host wide tags were enabled because the replaced scsi_find_tag() function had a special case for the tag value SCSI_NO_TAG to retrieve sdev->current_cmnd. The replacement function scsi_host_find_tag() has no such special case and returns NULL causing untagged commands to trigger a BUG() in the driver. Inspection shows that the 53c700 is the only driver using this SCSI_NO_TAG case, so a local fix in the driver suffices to fix this problem globally. Fixes: 64d513ac31b - "scsi: use host wide tags by default" Cc: stable@vger.kernel.org # 4.4+ Reported-by: Helge Deller <deller@gmx.de> Tested-by: Helge Deller <deller@gmx.de> Signed-off-by: James Bottomley <jejb@linux.vnet.ibm.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Ewan D. Milne <emilne@redhat.com> Acked-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
| | | * | | scsi: fix race between simultaneous decrements of ->host_failedWei Fang2016-06-093-4/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | sas_ata_strategy_handler() adds the works of the ata error handler to system_unbound_wq. This workqueue asynchronously runs work items, so the ata error handler will be performed concurrently on different CPUs. In this case, ->host_failed will be decreased simultaneously in scsi_eh_finish_cmd() on different CPUs, and become abnormal. It will lead to permanently inequality between ->host_failed and ->host_busy, and scsi error handler thread won't start running. IO errors after that won't be handled. Since all scmds must have been handled in the strategy handler, just remove the decrement in scsi_eh_finish_cmd() and zero ->host_busy after the strategy handler to fix this race. Fixes: 50824d6c5657 ("[SCSI] libsas: async ata-eh") Cc: stable@vger.kernel.org Signed-off-by: Wei Fang <fangwei1@huawei.com> Reviewed-by: James Bottomley <jejb@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
| * | | | | Merge branch 'for-linus-4.7-part2' of ↵Linus Torvalds2016-06-253-13/+34
| |\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull btrfs fixes part 2 from Chris Mason: "This has one patch from Omar to bring iterate_shared back to btrfs. We have a tree of work we queue up for directory items and it doesn't lend itself well to shared access. While we're cleaning it up, Omar has changed things to use an exclusive lock when there are delayed items" * 'for-linus-4.7-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: Btrfs: fix ->iterate_shared() by upgrading i_rwsem for delayed nodes
| | * | | | | Btrfs: fix ->iterate_shared() by upgrading i_rwsem for delayed nodesOmar Sandoval2016-06-253-13/+34
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit fe742fd4f90f ("Revert "btrfs: switch to ->iterate_shared()"") backed out the conversion to ->iterate_shared() for Btrfs because the delayed inode handling in btrfs_real_readdir() is racy. However, we can still do readdir in parallel if there are no delayed nodes. This is a temporary fix which upgrades the shared inode lock to an exclusive lock only when we have delayed items until we come up with a more complete solution. While we're here, rename the btrfs_{get,put}_delayed_items functions to make it very clear that they're just for readdir. Tested with xfstests and by doing a parallel kernel build: while make tinyconfig && make -j4 && git clean dqfx; do : done along with a bunch of parallel finds in another shell: while true; do for ((i=0; i<4; i++)); do find . >/dev/null & done wait done Signed-off-by: Omar Sandoval <osandov@fb.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Chris Mason <clm@fb.com>
| * | | | | | Merge branch 'for-linus-4.7' of ↵Linus Torvalds2016-06-2511-36/+57
| |\ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull btrfs fixes from Chris Mason: "I have a two part pull this time because one of the patches Dave Sterba collected needed to be against v4.7-rc2 or higher (we used rc4). I try to make my for-linus-xx branch testable on top of the last major so we can hand fixes to people on the list more easily, so I've split this pull in two. This first part has some fixes and two performance improvements that we've been testing for some time. Josef's two performance fixes are most notable. The transid tracking patch makes a big improvement on pretty much every workload" * 'for-linus-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: Btrfs: Force stripesize to the value of sectorsize btrfs: fix disk_i_size update bug when fallocate() fails Btrfs: fix error handling in map_private_extent_buffer Btrfs: fix error return code in btrfs_init_test_fs() Btrfs: don't do nocow check unless we have to btrfs: fix deadlock in delayed_ref_async_start Btrfs: track transid for delayed ref flushing
| | * | | | | | Btrfs: Force stripesize to the value of sectorsizeChandan Rajendra2016-06-232-6/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Btrfs code currently assumes stripesize to be same as sectorsize. However Btrfs-progs (until commit df05c7ed455f519e6e15e46196392e4757257305) has been setting btrfs_super_block->stripesize to a value of 4096. This commit makes sure that the value of btrfs_super_block->stripesize is a power of 2. Later, it unconditionally sets btrfs_root->stripesize to sectorsize. Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Chris Mason <clm@fb.com>
| | * | | | | | btrfs: fix disk_i_size update bug when fallocate() failsWang Xiaoguang2016-06-231-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When doing truncate operation, btrfs_setsize() will first call truncate_setsize() to set new inode->i_size, but if later btrfs_truncate() fails, btrfs_setsize() will call "i_size_write(inode, BTRFS_I(inode)->disk_i_size)" to reset the inmemory inode size, now bug occurs. It's because for truncate case btrfs_ordered_update_i_size() directly uses inode->i_size to update BTRFS_I(inode)->disk_i_size, indeed we should use the "offset" argument to update disk_i_size. Here is the call graph: ==>btrfs_truncate() ====>btrfs_truncate_inode_items() ======>btrfs_ordered_update_i_size(inode, last_size, NULL); Here btrfs_ordered_update_i_size()'s offset argument is last_size. And below test case can reveal this bug: dd if=/dev/zero of=fs.img bs=$((1024*1024)) count=100 dev=$(losetup --show -f fs.img) mkdir -p /mnt/mntpoint mkfs.btrfs -f $dev mount $dev /mnt/mntpoint cd /mnt/mntpoint echo "workdir is: /mnt/mntpoint" blocksize=$((128 * 1024)) dd if=/dev/zero of=testfile bs=$blocksize count=1 sync count=$((17*1024*1024*1024/blocksize)) echo "file size is:" $((count*blocksize)) for ((i = 1; i <= $count; i++)); do i=$((i + 1)) dst_offset=$((blocksize * i)) xfs_io -f -c "reflink testfile 0 $dst_offset $blocksize"\ testfile > /dev/null done sync truncate --size 0 testfile ls -l testfile du -sh testfile exit In this case, truncate operation will fail for enospc reason and "du -sh testfile" returns value greater than 0, but testfile's size is 0, we need to reflect correct inode->i_size. Signed-off-by: Wang Xiaoguang <wangxg.fnst@cn.fujitsu.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Chris Mason <clm@fb.com>
| | * | | | | | Btrfs: fix error handling in map_private_extent_bufferLiu Bo2016-06-232-2/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | map_private_extent_buffer() can return -EINVAL in two different cases, 1. when the requested contents span two pages if nodesize is larger than pagesize, 2. when it detects something insane. The 2nd one used to be only a WARN_ON(1), and we decided to return a error to callers, but we didn't fix up all its callers, which will be addressed by this patch. Without this, btrfs may end up with 'general protection', ie. reading invalid memory. Reported-by: Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Chris Mason <clm@fb.com>
| | * | | | | | Btrfs: fix error return code in btrfs_init_test_fs()Wei Yongjun2016-06-231-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix to return a negative error code from the kern_mount() error handling case instead of 0(ret is set to 0 by register_filesystem), as done elsewhere in this function. Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Reviewed-by: Omar Sandoval <osandov@fb.com> Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Chris Mason <clm@fb.com>
| | * | | | | | Btrfs: don't do nocow check unless we have toJosef Bacik2016-06-231-22/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Before we write into prealloc/nocow space we have to make sure that there are no references to the extents we are writing into, which means checking the extent tree and csum tree in the case of nocow. So we don't want to do the nocow dance unless we can't reserve data space, since it's a serious drag on performance. With the following sequence fallocate -l10737418240 /mnt/btrfs-test/file cp --reflink /mnt/btrfs-test/file /mnt/btrfs-test/link fio --name=randwrite --rw=randwrite --bs=4k --filename=/mnt/btrfs-test/file \ --end_fsync=1 we get the worst case scenario where we have to fall back on to doing the check anyway. Without this patch lat (usec): min=5, max=111598, avg=27.65, stdev=124.51 write: io=10240MB, bw=126876KB/s, iops=31718, runt= 82646msec With this patch lat (usec): min=3, max=91210, avg=14.09, stdev=110.62 write: io=10240MB, bw=212753KB/s, iops=53188, runt= 49286msec We get twice the throughput, half of the runtime, and half of the average latency. Thanks, Signed-off-by: Josef Bacik <jbacik@fb.com> [ PAGE_CACHE_ removal related fixups ] Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Chris Mason <clm@fb.com>
| | * | | | | | btrfs: fix deadlock in delayed_ref_async_startChris Mason2016-06-231-9/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | "Btrfs: track transid for delayed ref flushing" was deadlocking on btrfs_attach_transaction because its not safe to call from the async delayed ref start code. This commit brings back btrfs_join_transaction instead and checks for a blocked commit. Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Chris Mason <clm@fb.com>
| | * | | | | | Btrfs: track transid for delayed ref flushingJosef Bacik2016-06-234-5/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Using the offwakecputime bpf script I noticed most of our time was spent waiting on the delayed ref throttling. This is what is supposed to happen, but sometimes the transaction can commit and then we're waiting for throttling that doesn't matter anymore. So change this stuff to be a little smarter by tracking the transid we were in when we initiated the throttling. If the transaction we get is different then we can just bail out. This resulted in a 50% speedup in my fs_mark test, and reduced the amount of time spent throttling by 60 seconds over the entire run (which is about 30 minutes). Thanks, Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Chris Mason <clm@fb.com>
| * | | | | | | Merge tag 'sound-4.7-rc5' of ↵Linus Torvalds2016-06-254-12/+19
| |\ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound Pull sound fixes from Takashi Iwai: "Again pretty calm weeks: we've had only a few trivial / stable HD-audio fixes in addition to a possible race fix for snd-dummy driver spotted by syzkaller" * tag 'sound-4.7-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: ALSA: dummy: Fix a use-after-free at closing ALSA: hda / realtek - add two more Thinkpad IDs (5050,5053) for tpt460 fixup ALSA: hda - Fix the headset mic jack detection on Dell machine ALSA: hda/tegra: iomem fixups for sparse warnings ALSA: hdac_regmap - fix the register access for runtime PM
| * \ \ \ \ \ \ \ Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds2016-06-251-0/+12
| |\ \ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 kprobe fix from Thomas Gleixner: "A single fix clearing the TF bit when a fault is single stepped" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: kprobes/x86: Clear TF bit in fault on single-stepping
| | * | | | | | | | kprobes/x86: Clear TF bit in fault on single-steppingMasami Hiramatsu2016-06-141-0/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix kprobe_fault_handler() to clear the TF (trap flag) bit of the flags register in the case of a fault fixup on single-stepping. If we put a kprobe on the instruction which caused a page fault (e.g. actual mov instructions in copy_user_*), that fault happens on the single-stepping buffer. In this case, kprobes resets running instance so that the CPU can retry execution on the original ip address. However, current code forgets to reset the TF bit. Since this fault happens with TF bit set for enabling single-stepping, when it retries, it causes a debug exception and kprobes can not handle it because it already reset itself. On the most of x86-64 platform, it can be easily reproduced by using kprobe tracer. E.g. # cd /sys/kernel/debug/tracing # echo p copy_user_enhanced_fast_string+5 > kprobe_events # echo 1 > events/kprobes/enable And you'll see a kernel panic on do_debug(), since the debug trap is not handled by kprobes. To fix this problem, we just need to clear the TF bit when resetting running kprobe. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Reviewed-by: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: systemtap@sourceware.org Cc: stable@vger.kernel.org # All the way back to ancient kernels Link: http://lkml.kernel.org/r/20160611140648.25885.37482.stgit@devbox [ Updated the comments. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
| * | | | | | | | | Merge branch 'sched-urgent-for-linus' of ↵Linus Torvalds2016-06-253-21/+66
| |\ \ \ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Thomas Gleixner: "A couple of scheduler fixes: - force watchdog reset while processing sysrq-w - fix a deadlock when enabling trace events in the scheduler - fixes to the throttled next buddy logic - fixes for the average accounting (missing serialization and underflow handling) - allow kernel threads for fallback to online but not active cpus" * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/core: Allow kthreads to fall back to online && !active cpus sched/fair: Do not announce throttled next buddy in dequeue_task_fair() sched/fair: Initialize throttle_count for new task-groups lazily sched/fair: Fix cfs_rq avg tracking underflow kernel/sysrq, watchdog, sched/core: Reset watchdog on all CPUs while processing sysrq-w sched/debug: Fix deadlock when enabling sched events sched/fair: Fix post_init_entity_util_avg() serialization
| | * | | | | | | | | sched/core: Allow kthreads to fall back to online && !active cpusTejun Heo2016-06-241-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | During CPU hotplug, CPU_ONLINE callbacks are run while the CPU is online but not active. A CPU_ONLINE callback may create or bind a kthread so that its cpus_allowed mask only allows the CPU which is being brought online. The kthread may start executing before the CPU is made active and can end up in select_fallback_rq(). In such cases, the expected behavior is selecting the CPU which is coming online; however, because select_fallback_rq() only chooses from active CPUs, it determines that the task doesn't have any viable CPU in its allowed mask and ends up overriding it to cpu_possible_mask. CPU_ONLINE callbacks should be able to put kthreads on the CPU which is coming online. Update select_fallback_rq() so that it follows cpu_online() rather than cpu_active() for kthreads. Reported-by: Gautham R Shenoy <ego@linux.vnet.ibm.com> Tested-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Abdul Haleem <abdhalee@linux.vnet.ibm.com> Cc: Aneesh Kumar <aneesh.kumar@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kernel-team@fb.com Cc: linuxppc-dev@lists.ozlabs.org Link: http://lkml.kernel.org/r/20160616193504.GB3262@mtj.duckdns.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | | | | | sched/fair: Do not announce throttled next buddy in dequeue_task_fair()Konstantin Khlebnikov2016-06-241-5/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Hierarchy could be already throttled at this point. Throttled next buddy could trigger a NULL pointer dereference in pick_next_task_fair(). Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Ben Segall <bsegall@google.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/146608183552.21905.15924473394414832071.stgit@buzz Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | | | | | sched/fair: Initialize throttle_count for new task-groups lazilyKonstantin Khlebnikov2016-06-242-1/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Cgroup created inside throttled group must inherit current throttle_count. Broken throttle_count allows to nominate throttled entries as a next buddy, later this leads to null pointer dereference in pick_next_task_fair(). This patch initialize cfs_rq->throttle_count at first enqueue: laziness allows to skip locking all rq at group creation. Lazy approach also allows to skip full sub-tree scan at throttling hierarchy (not in this patch). Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bsegall@google.com Link: http://lkml.kernel.org/r/146608182119.21870.8439834428248129633.stgit@buzz Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | | | | | sched/fair: Fix cfs_rq avg tracking underflowPeter Zijlstra2016-06-201-8/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As per commit: b7fa30c9cc48 ("sched/fair: Fix post_init_entity_util_avg() serialization") > the code generated from update_cfs_rq_load_avg(): > > if (atomic_long_read(&cfs_rq->removed_load_avg)) { > s64 r = atomic_long_xchg(&cfs_rq->removed_load_avg, 0); > sa->load_avg = max_t(long, sa->load_avg - r, 0); > sa->load_sum = max_t(s64, sa->load_sum - r * LOAD_AVG_MAX, 0); > removed_load = 1; > } > > turns into: > > ffffffff81087064: 49 8b 85 98 00 00 00 mov 0x98(%r13),%rax > ffffffff8108706b: 48 85 c0 test %rax,%rax > ffffffff8108706e: 74 40 je ffffffff810870b0 <update_blocked_averages+0xc0> > ffffffff81087070: 4c 89 f8 mov %r15,%rax > ffffffff81087073: 49 87 85 98 00 00 00 xchg %rax,0x98(%r13) > ffffffff8108707a: 49 29 45 70 sub %rax,0x70(%r13) > ffffffff8108707e: 4c 89 f9 mov %r15,%rcx > ffffffff81087081: bb 01 00 00 00 mov $0x1,%ebx > ffffffff81087086: 49 83 7d 70 00 cmpq $0x0,0x70(%r13) > ffffffff8108708b: 49 0f 49 4d 70 cmovns 0x70(%r13),%rcx > > Which you'll note ends up with sa->load_avg -= r in memory at > ffffffff8108707a. So I _should_ have looked at other unserialized users of ->load_avg, but alas. Luckily nikbor reported a similar /0 from task_h_load() which instantly triggered recollection of this here problem. Aside from the intermediate value hitting memory and causing problems, there's another problem: the underflow detection relies on the signed bit. This reduces the effective width of the variables, IOW its effectively the same as having these variables be of signed type. This patch changes to a different means of unsigned underflow detection to not rely on the signed bit. This allows the variables to use the 'full' unsigned range. And it does so with explicit LOAD - STORE to ensure any intermediate value will never be visible in memory, allowing these unserialized loads. Note: GCC generates crap code for this, might warrant a look later. Note2: I say 'full' above, if we end up at U*_MAX we'll still explode; maybe we should do clamping on add too. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Yuyang Du <yuyang.du@intel.com> Cc: bsegall@google.com Cc: kernel@kyup.com Cc: morten.rasmussen@arm.com Cc: pjt@google.com Cc: steve.muckle@linaro.org Fixes: 9d89c257dfb9 ("sched/fair: Rewrite runnable load and utilization average tracking") Link: http://lkml.kernel.org/r/20160617091948.GJ30927@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
| | * | | | | | | | | kernel/sysrq, watchdog, sched/core: Reset watchdog on all CPUs while ↵Andrey Ryabinin2016-06-141-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | processing sysrq-w Lengthy output of sysrq-w may take a lot of time on slow serial console. Currently we reset NMI-watchdog on the current CPU to avoid spurious lockup messages. Sometimes this doesn't work since softlockup watchdog might trigger on another CPU which is waiting for an IPI to proceed. We reset softlockup watchdogs on all CPUs, but we do this only after listing all tasks, and this may be too late on a busy system. So, reset watchdogs CPUs earlier, in for_each_process_thread() loop. Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/1465474805-14641-1-git-send-email-aryabinin@virtuozzo.com Signed-off-by: Ingo Molnar <mingo@kernel.org>