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2017-01-26HID: usbhid: Quirk a AMI virtual mouse and keyboard with ALWAYS_POLLColin Ian King
Quirking the following AMI USB device with ALWAYS_POLL fixes an AMI virtual keyboard and mouse from not responding and timing out when it is attached to a ppc64el Power 8 system and when we have some rapid open/closes on the mouse device. usb 1-3: new high-speed USB device number 2 using xhci_hcd usb 1-3: New USB device found, idVendor=046b, idProduct=ff01 usb 1-3: New USB device strings: Mfr=1, Product=2, SerialNumber=3 usb 1-3: Product: Virtual Hub usb 1-3: Manufacturer: American Megatrends Inc. usb 1-3: SerialNumber: serial usb 1-3.3: new high-speed USB device number 3 using xhci_hcd usb 1-3.3: New USB device found, idVendor=046b, idProduct=ff31 usb 1-3.3: New USB device strings: Mfr=1, Product=2, SerialNumber=3 usb 1-3.3: Product: Virtual HardDisk Device usb 1-3.3: Manufacturer: American Megatrends Inc. usb 1-3.4: new low-speed USB device number 4 using xhci_hcd usb 1-3.4: New USB device found, idVendor=046b, idProduct=ff10 usb 1-3.4: New USB device strings: Mfr=1, Product=2, SerialNumber=0 usb 1-3.4: Product: Virtual Keyboard and Mouse usb 1-3.4: Manufacturer: American Megatrends Inc. With the quirk I have not been able to trigger the issue with half an hour of saturation soak testing. Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2017-01-26HID: wacom: Fix poor prox handling in 'wacom_pl_irq'Jason Gerecke
Commit 025bcc1 performed cleanup work on the 'wacom_pl_irq' function, making it follow the standards used in the rest of the codebase. The change unintiontionally allowed the function to send input events from reports that are not marked as being in prox. This can cause problems as the report values for X, Y, etc. are not guaranteed to be correct. In particular, occasionally the tablet will send a report with these values set to zero. If such a report is received it can caus an unexpected jump in the XY position. This patch surrounds more of the processing code with a proximity check, preventing these zeroed reports from overwriting the current state. To be safe, only the tool type and ABS_MISC events should be reported when the pen is marked as being out of prox. Fixes: 025bcc1540 ("HID: wacom: Simplify 'wacom_pl_irq'") Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com> Reviewed-by: Ping Cheng <pingc@wacom.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2017-01-26Merge tag 'pinctrl-v4.10-3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl Pull pin control fixes from Linus Walleij: "A bunch of pin control fixes for v4.10 that didn't get sent off until now, sorry for the delay. It's only driver fixes: - A bunch of fixes to the Intel drivers: broxton, baytrail. Bugs related to register offsets, IRQ, debounce functionality. - Fix a conflict amongst UART settings on the meson. - Fix the ethernet setting on the Uniphier. - A compilation warning squelched" * tag 'pinctrl-v4.10-3' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: pinctrl: uniphier: fix Ethernet (RMII) pin-mux setting for LD20 pinctrl: meson: fix uart_ao_b for GXBB and GXL/GXM pinctrl: amd: avoid maybe-uninitalized warning pinctrl: baytrail: Do not add all GPIOs to IRQ domain pinctrl: baytrail: Rectify debounce support pinctrl: intel: Set pin direction properly pinctrl: broxton: Use correct PADCFGLOCK offset
2017-01-26Revert "sd: remove __data_len hack for WRITE SAME"Bart Van Assche
This patch reverts commit f80de881d8df and avoids that sending a WRITE SAME command to the iSCSI initiator triggers the following: BUG: unable to handle kernel NULL pointer dereference at 0000000000000014 TARGET_CORE[iSCSI]: Expected Transfer Length: 260096 does not match SCSI CDB Length: 512 for SAM Opcode: 0x41 IP: iscsi_tcp_segment_done+0x20b/0x310 [libiscsi_tcp] Oops: 0000 [#1] SMP Modules linked in: target_core_user uio target_core_iblock target_core_file iscsi_target_mod target_core_mod netconsole configfs crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel aes_x86_64 crypto_simd cryptd glue_helper virtio_console virtio_rng virtio_balloon serio_raw i2c_piix4 acpi_cpufreq button iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi ext4 jbd2 mbcache virtio_blk virtio_net psmouse floppy drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ttm drm virtio_pci CPU: 2 PID: 5 Comm: kworker/u8:0 Not tainted 4.10.0-rc5-debug+ #3 Workqueue: iscsi_q_0 iscsi_xmitworker [libiscsi] RIP: 0010:iscsi_tcp_segment_done+0x20b/0x310 [libiscsi_tcp] Call Trace: iscsi_sw_tcp_xmit_segment+0x84/0x120 [iscsi_tcp] iscsi_sw_tcp_pdu_xmit+0x51/0x180 [iscsi_tcp] iscsi_tcp_task_xmit+0xb3/0x290 [libiscsi_tcp] iscsi_xmit_task+0x4e/0xc0 [libiscsi] iscsi_xmitworker+0x243/0x330 [libiscsi] process_one_work+0x1d8/0x4b0 worker_thread+0x49/0x4a0 kthread+0x102/0x140 Fixes: f80de881d8df ("sd: remove __data_len hack for WRITE SAME") Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com> Cc: Hannes Reinecke <hare@suse.com> Cc: Sagi Grimberg <sagi@grimberg.me> Cc: Jens Axboe <axboe@fb.com> Cc: Lee Duncan <lduncan@suse.com> Cc: Chris Leech <cleech@redhat.com> Acked-by: Christoph Hellwig <hch@lst.de> Acked-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-01-26Merge branch 'nvme-4.10-fixes' of git://git.infradead.org/nvme into for-linusJens Axboe
Pull nvme target fixes from Sagi: Given that its -rc6, I removed anything that is not bug fix. - nvmet-fc discard fix from Christoph - queue disconnect fix from James - nvmet-rdma dma sync fix from Parav - Some more nvmet fixes
2017-01-26Merge tag 'drm-fixes-for-v4.10-rc6-revert-one' of ↵Linus Torvalds
git://people.freedesktop.org/~airlied/linux Pull drm revert from Dave Airlie: "Revert one patch missing some prereqs. One of the connector fixes was missing some prereqs, we have an alternate driver fix that should work that I'll send tomorrow. Today is a holiday here so quickly smashing this out" Daniel Vetter explains: "I pushed a locking change to fix a nouveau rpm issue to -fixes that needed the connector_list rework. And that's only in -next, but I missed that. Dave has the revert in a pull, and he'll follow-up with the hack nouveau patch for 4.10, and then we'll reapply the proper fix again for -next and revert the hacks. A bit a mess, but should be sorted soon" * tag 'drm-fixes-for-v4.10-rc6-revert-one' of git://people.freedesktop.org/~airlied/linux: Revert "drm/probe-helpers: Drop locking from poll_enable"
2017-01-26nvme-fc: use blk_rq_nr_phys_segmentsChristoph Hellwig
Without this deallocate won't work properly due to the mismatch of the bio/request size and the actual payload size. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: James Smart <james.smart@broadcom.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2017-01-26nvmet-rdma: Fix missing dma sync to nvme data structuresParav Pandit
This patch performs dma sync operations on nvme_command and nvme_completion. nvme_command is synced (a) on receiving of the recv queue completion for cpu access. (b) before posting recv wqe back to rdma adapter for device access. nvme_completion is synced (a) on receiving of the recv queue completion of associated nvme_command for cpu access. (b) before posting send wqe to rdma adapter for device access. This patch is generated for git://git.infradead.org/nvme-fabrics.git Branch: nvmf-4.10 Signed-off-by: Parav Pandit <parav@mellanox.com> Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
2017-01-26nvmet: Call fatal_error from keep-alive timout expirationSagi Grimberg
We only need to call delete_ctrl once, so given that both keep-alive timeout and any other fatal error can trigger it, just make sure we only call delete_ctrl once. Signed-off-by: Sagi Grimberg <sagi@grimberg.me> Reviewed-by: Christoph Hellwig <hch@lst.de>
2017-01-26nvmet: cancel fatal error and flush async work before free controllerSagi Grimberg
Make sure they are not running and we can free the controller safely. Signed-off-by: Roy Shterman <roys@lightbitslabs.com> Signed-off-by: Sagi Grimberg <sagi@grimberg.me> Reviewed-by: Christoph Hellwig <hch@lst.de>
2017-01-26nvmet: delete controllers deletion upon subsystem releaseSagi Grimberg
No reason for them to be kept around if we are deleting the subsystem, so instead of passively wait for the host to disconnect, actively delete the controllers. Signed-off-by: Sagi Grimberg <sagi@grimberg.me> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Max Gurtovoy <maxg@mellanox.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2017-01-26nvmet_fc: correct logic in disconnect queue LS handlingJames Smart
Correct logic in disconnect queue LS handling. Rework so that queue searching and error reporting is above the section to send back a ls rjt Signed-off-by: James Smart <james.smart@broadcom.com> Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2017-01-25virtio_net: reject XDP programs using header adjustmentJakub Kicinski
commit 17bedab27231 ("bpf: xdp: Allow head adjustment in XDP prog") added a new XDP helper to prepend and remove data from a frame. Make virtio_net reject programs making use of this helper until proper support is added. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Acked-by: John Fastabend <john.r.fastabend@intel.com> Acked-by: Jason Wang <jasowang@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-25virtio_net: use dev_kfree_skb for small buffer XDP receiveJohn Fastabend
In the small buffer case during driver unload we currently use put_page instead of dev_kfree_skb. Resolve this by adding a check for virtnet mode when checking XDP queue type. Also name the function so that the code reads correctly to match the additional check. Fixes: bb91accf2733 ("virtio-net: XDP support for small buffers") Signed-off-by: John Fastabend <john.r.fastabend@intel.com> Acked-by: Jason Wang <jasowang@redhat.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-25r8152: check rx after napi is enabledhayeswang
Schedule the napi after napi_enable() for rx, if it is necessary. If the rx is completed when napi is disabled, the sheduling of napi would be lost. Then, no one handles the rx packet until next napi is scheduled. Signed-off-by: Hayes Wang <hayeswang@realtek.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-25r8152: re-schedule napi for txhayeswang
Re-schedule napi after napi_complete() for tx, if it is necessay. In r8152_poll(), if the tx is completed after tx_bottom() and before napi_complete(), the scheduling of napi would be lost. Then, no one handles the next tx until the next napi_schedule() is called. Signed-off-by: Hayes Wang <hayeswang@realtek.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-25r8152: avoid start_xmit to schedule napi when napi is disabledhayeswang
Stop the tx when the napi is disabled to prevent napi_schedule() is called. Signed-off-by: Hayes Wang <hayeswang@realtek.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-25r8152: avoid start_xmit to call napi_schedule during autosuspendhayeswang
Adjust the setting of the flag of SELECTIVE_SUSPEND to prevent start_xmit() from calling napi_schedule() directly during runtime suspend. After calling napi_disable() or clearing the flag of WORK_ENABLE, scheduling the napi is useless. Signed-off-by: Hayes Wang <hayeswang@realtek.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-26i2c: imx-lpi2c: add VLLS mode supportGao Pan
When system enters VLLS mode, module power is turned off. As a result, all registers are reset to HW default value. After exiting VLLS mode, registers are still in default mode. As a result, the pinctrl settings are incorrect, which will affect the module function. The patch recovers the pinctrl setting when exit VLLS mode. Signed-off-by: Gao Pan <pandy.gao@nxp.com> Reviewed-by: Vladimir Zapolskiy <vz@mleia.com> [wsa: added missing include] Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-01-25Revert "drm/radeon: always apply pci shutdown callbacks"Alex Deucher
This seems to break reboot on some evergreen systems. bugs: https://bugs.freedesktop.org/show_bug.cgi?id=99524 https://bugzilla.kernel.org/show_bug.cgi?id=192271 This reverts commit a481daa88fd4d6b54f25348972bba10b5f6a84d0. Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Cc: stable@vger.kernel.org
2017-01-25i2c: i2c-cadence: Initialize configuration before probing devicesMike Looijmans
The cadence I2C driver calls cdns_i2c_writereg(..) to setup a workaround in the controller, but did so after calling i2c_add_adapter() which starts probing devices on the bus. Change the order so that the configuration is completely finished before using the adapter. Signed-off-by: Mike Looijmans <mike.looijmans@topic.nl> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2017-01-26Revert "drm/probe-helpers: Drop locking from poll_enable"Dave Airlie
This reverts commit 3846fd9b86001bea171943cc3bb9222cb6da6b42. There were some precursor commits missing for this around connector locking, we should probably merge Lyude's nouveau avoid the problem patch.
2017-01-25net: phy: leds: Break dependency of phy.h on phy_led_triggers.hGeert Uytterhoeven
<linux/phy.h> includes <linux/phy_led_triggers.h>, which is not really needed. Drop the include from <linux/phy.h>, and add it to all users that didn't include it explicitly. Suggested-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-25net: phy: leds: Clear phy_num_led_triggers on failure to avoid crashGeert Uytterhoeven
phy_attach_direct() ignores errors returned by phy_led_triggers_register(). I think that's OK, as LED triggers can be considered a non-critical feature. However, this causes problems later: - phy_led_trigger_change_speed() will access the array phy_device.phy_led_triggers, which has been freed in the error path of phy_led_triggers_register(), which may lead to a crash. - phy_led_triggers_unregister() will access the same array, leading to crashes during s2ram or poweroff, like: Unable to handle kernel NULL pointer dereference at virtual address 00000000 ... [<c04116d4>] (__list_del_entry_valid) from [<c05e8948>] (led_trigger_unregister+0x34/0xcc) [<c05e8948>] (led_trigger_unregister) from [<c05336c4>] (phy_led_triggers_unregister+0x28/0x34) [<c05336c4>] (phy_led_triggers_unregister) from [<c0531d44>] (phy_detach+0x30/0x74) [<c0531d44>] (phy_detach) from [<c0538bdc>] (sh_eth_close+0x64/0x9c) [<c0538bdc>] (sh_eth_close) from [<c04d4ce0>] (dpm_run_callback+0x48/0xc8) or: list_del corruption. prev->next should be dede6540, but was 2e323931 ------------[ cut here ]------------ kernel BUG at lib/list_debug.c:52! ... [<c02f6d70>] (__list_del_entry_valid) from [<c0425168>] (led_trigger_unregister+0x34/0xcc) [<c0425168>] (led_trigger_unregister) from [<c03a05a0>] (phy_led_triggers_unregister+0x28/0x34) [<c03a05a0>] (phy_led_triggers_unregister) from [<c039ec04>] (phy_detach+0x30/0x74) [<c039ec04>] (phy_detach) from [<c03a4fc0>] (sh_eth_close+0x6c/0xa4) [<c03a4fc0>] (sh_eth_close) from [<c0483234>] (__dev_close_many+0xac/0xd0) To fix this, clear phy_device.phy_num_led_triggers in the error path of phy_led_triggers_register() fails. Note that the "No phy led trigger registered for speed" message will still be printed on link speed changes, which is a good cue that something went wrong with the LED triggers. Fixes: 2e0bc452f4721520 ("net: phy: leds: add support for led triggers on phy link state change") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-25net-next: ethernet: mediatek: change the compatible stringJohn Crispin
When the binding was defined, I was not aware that mt2701 was an earlier version of the SoC. For sake of consistency, the ethernet driver should use mt2701 inside the compat string as this is the earliest SoC with the ethernet core. The ethernet driver is currently of no real use until we finish and upstream the DSA driver. There are no users of this binding yet. It should be safe to fix this now before it is too late and we need to provide backward compatibility for the mt7623-eth compat string. Reported-by: Sean Wang <sean.wang@mediatek.com> Signed-off-by: John Crispin <john@phrozen.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-25bnxt_en: Fix RTNL lock usage on bnxt_get_port_module_status().Michael Chan
bnxt_get_port_module_status() calls bnxt_update_link() which expects RTNL to be held. In bnxt_sp_task() that does not hold RTNL, we need to call it with a prior call to bnxt_rtnl_lock_sp() and the call needs to be moved to the end of bnxt_sp_task(). Signed-off-by: Michael Chan <michael.chan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-25bnxt_en: Fix RTNL lock usage on bnxt_update_link().Michael Chan
bnxt_update_link() is called from multiple code paths. Most callers, such as open, ethtool, already hold RTNL. Only the caller bnxt_sp_task() does not. So it is a bug to take RTNL inside bnxt_update_link(). Fix it by removing the RTNL inside bnxt_update_link(). The function now expects the caller to always hold RTNL. In bnxt_sp_task(), call bnxt_rtnl_lock_sp() before calling bnxt_update_link(). We also need to move the call to the end of bnxt_sp_task() since it will be clearing the BNXT_STATE_IN_SP_TASK bit. Signed-off-by: Michael Chan <michael.chan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-25bnxt_en: Fix bnxt_reset() in the slow path task.Michael Chan
In bnxt_sp_task(), we set a bit BNXT_STATE_IN_SP_TASK so that bnxt_close() will synchronize and wait for bnxt_sp_task() to finish. Some functions in bnxt_sp_task() require us to clear BNXT_STATE_IN_SP_TASK and then acquire rtnl_lock() to prevent race conditions. There are some bugs related to this logic. This patch refactors the code to have common bnxt_rtnl_lock_sp() and bnxt_rtnl_unlock_sp() to handle the RTNL and the clearing/setting of the bit. Multiple functions will need the same logic. We also need to move bnxt_reset() to the end of bnxt_sp_task(). Functions that clear BNXT_STATE_IN_SP_TASK must be the last functions to be called in bnxt_sp_task(). The common scheme will handle the condition properly. Signed-off-by: Michael Chan <michael.chan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-25Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhostLinus Torvalds
Pull virtio/vhost fixes from Michael Tsirkin: - ARM DMA fixes - vhost vsock bugfix * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: vring: Force use of DMA API for ARM-based systems with legacy devices virtio_mmio: Set DMA masks appropriately vhost/vsock: handle vhost_vq_init_access() error
2017-01-25Revert "ACPI / video: Add force_native quirk for HP Pavilion dv6"Hans de Goede
Revert commit 6276e53fa8c0 (ACPI / video: Add force_native quirk for HP Pavilion dv6). In the commit message for the quirk this revert removes I wrote: "Note that there are quite a few HP Pavilion dv6 variants, some woth ATI and some with NVIDIA hybrid gfx, both seem to need this quirk to have working backlight control. There are also some versions with only Intel integrated gfx, these may not need this quirk, but it should not hurt there." Unfortunately that seems wrong, I've already received 2 reports of this commit causing regressions on some dv6 variants (at least one of which actually has a nvidia GPU). So it seems that HP has made a mess here by using the same model-name both in marketing and in the DMI data for many different variants. Some of which need acpi_backlight=native for functional backlight control (as the quirk this commit reverts was doing), where as others are broken by it. So lets get back to the old sitation so as to avoid regressing on models which used to work without any kernel cmdline arguments before. Fixes: 6276e53fa8c0 (ACPI / video: Add force_native quirk for HP Pavilion dv6) Signed-off-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2017-01-25Merge tag 'gvt-fixes-2017-01-25' of https://github.com/01org/gvt-linux into ↵Jani Nikula
drm-intel-fixes gvt-fixes-2017-01-25 - re-enable shadow batch buffer for security that was falsely turned off. - kvmgt/mdev typo fix for correct ABI - gvt mail list change Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2017-01-25drm/i915: reinstate call to trace_i915_vma_bindDaniele Ceraolo Spurio
The call went away in: commit 3b16525cc4c1a43e9053cfdc414356eea24bdfad Author: Chris Wilson <chris@chris-wilson.co.uk> Date: Thu Aug 4 16:32:25 2016 +0100 drm/i915: Split insertion/binding of an object into the VM It is useful to have this trace as it pairs nicely with the vma_unbind one to track vma activity. Added inside the i915_vma_bind function (was outside before) to keep a similar placement as trace_i915_vma_unbind. v2: print bind_flags instead of flags (Chris) Fixes: 3b16525cc4c1 ("drm/i915: Split insertion/binding of an object into the VM") Cc: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1484949083-11430-1-git-send-email-daniele.ceraolospurio@intel.com Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> (cherry picked from commit 6146e6da5c961735dacf9b6c0c8b5f1382193ee2) Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2017-01-25drm/i915: Move atomic state free from out of fence releaseChris Wilson
Fences are required to support being released from under an atomic context. The drm_atomic_state struct may take a mutex when being released and so we cannot drop a reference to the drm_atomic_state from the fence release path directly, and so we need to defer that unreference to a worker. [ 326.576697] WARNING: CPU: 2 PID: 366 at kernel/sched/core.c:7737 __might_sleep+0x5d/0x80 [ 326.576816] do not call blocking ops when !TASK_RUNNING; state=1 set at [<ffffffffc0359549>] intel_breadcrumbs_signaler+0x59/0x270 [i915] [ 326.576818] Modules linked in: rfcomm fuse snd_hda_codec_hdmi bnep snd_hda_codec_realtek snd_hda_codec_generic snd_hda_intel snd_hda_codec snd_hwdep snd_hda_core snd_pcm snd_seq_midi snd_seq_midi_event snd_rawmidi snd_seq snd_seq_device snd_timer input_leds led_class snd punit_atom_debug btusb btrtl btbcm btintel intel_rapl bluetooth i915 drm_kms_helper syscopyarea sysfillrect iwlwifi sysimgblt soundcore fb_sys_fops mei_txe cfg80211 drm pwm_lpss_platform pwm_lpss pinctrl_cherryview fjes acpi_pad parport_pc ppdev parport autofs4 [ 326.576899] CPU: 2 PID: 366 Comm: i915/signal:0 Tainted: G U 4.10.0-rc3-patser+ #5030 [ 326.576902] Hardware name: /NUC5PPYB, BIOS PYBSWCEL.86A.0031.2015.0601.1712 06/01/2015 [ 326.576905] Call Trace: [ 326.576920] dump_stack+0x4d/0x6d [ 326.576926] __warn+0xc0/0xe0 [ 326.576931] warn_slowpath_fmt+0x5a/0x80 [ 326.577004] ? intel_breadcrumbs_signaler+0x59/0x270 [i915] [ 326.577075] ? intel_breadcrumbs_signaler+0x59/0x270 [i915] [ 326.577079] __might_sleep+0x5d/0x80 [ 326.577087] mutex_lock+0x1b/0x40 [ 326.577133] drm_property_free_blob+0x1e/0x80 [drm] [ 326.577167] ? drm_property_destroy+0xe0/0xe0 [drm] [ 326.577200] drm_mode_object_unreference+0x5c/0x70 [drm] [ 326.577233] drm_property_unreference_blob+0xe/0x10 [drm] [ 326.577260] __drm_atomic_helper_crtc_destroy_state+0x14/0x40 [drm_kms_helper] [ 326.577278] drm_atomic_helper_crtc_destroy_state+0x10/0x20 [drm_kms_helper] [ 326.577352] intel_crtc_destroy_state+0x9/0x10 [i915] [ 326.577388] drm_atomic_state_default_clear+0xea/0x1d0 [drm] [ 326.577462] intel_atomic_state_clear+0xd/0x20 [i915] [ 326.577497] drm_atomic_state_clear+0x1a/0x30 [drm] [ 326.577532] __drm_atomic_state_free+0x13/0x60 [drm] [ 326.577607] intel_atomic_commit_ready+0x6f/0x78 [i915] [ 326.577670] i915_sw_fence_release+0x3a/0x50 [i915] [ 326.577733] dma_i915_sw_fence_wake+0x39/0x80 [i915] [ 326.577741] dma_fence_signal+0xda/0x120 [ 326.577812] ? intel_breadcrumbs_signaler+0x59/0x270 [i915] [ 326.577884] intel_breadcrumbs_signaler+0xb1/0x270 [i915] [ 326.577889] kthread+0x127/0x130 [ 326.577961] ? intel_engine_remove_wait+0x1a0/0x1a0 [i915] [ 326.577964] ? kthread_stop+0x120/0x120 [ 326.577970] ret_from_fork+0x22/0x30 Fixes: c004a90b7263 ("drm/i915: Restore nonblocking awaits for modesetting") Reported-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Link: http://patchwork.freedesktop.org/patch/msgid/20170123212939.30345-1-chris@chris-wilson.co.uk Cc: <drm-intel-fixes@lists.freedesktop.org> # v4.10-rc1+ Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> (cherry picked from commit eb955eee27d9dc176871540c43c9070ee4701642) Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2017-01-25drm/i915: Check for NULL atomic state in intel_crtc_disable_noatomic()Ander Conselvan de Oliveira
In intel_crtc_disable_noatomic(), bail on a failure to allocate an atomic state to avoid a NULL pointer dereference. Fixes: 4a80655827af ("drm/i915: Pass atomic state to crtc enable/disable functions") Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Daniel Vetter <daniel.vetter@intel.com> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: intel-gfx@lists.freedesktop.org Cc: <stable@vger.kernel.org> # v4.9+ Signed-off-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1484922525-6131-4-git-send-email-ander.conselvan.de.oliveira@intel.com (cherry picked from commit 31bb2ef97ea9db343348f9b5ccaa9bb6f48fc655) Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2017-01-25drm/i915: Fix calculation of rotated x and y offsets for planar formatsAnder Conselvan de Oliveira
Parameters tile_size, tile_width and tile_height were passed in the wrong order to _intel_adjust_tile_offset() when calculating the rotated offsets. This doesn't fix any user visible bug, since for packed formats new and old offset are the same and the rotated offsets are within a tile before they are fed to _intel_adjust_tile_offset(). In that case, the offsets are unchanged. That is not true for planar formats, but those are currently not supported. Fixes: 66a2d927cb0e ("drm/i915: Make intel_adjust_tile_offset() work for linear buffers") Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Sivakumar Thulasimani <sivakumar.thulasimani@intel.com> Cc: Daniel Vetter <daniel.vetter@intel.com> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: intel-gfx@lists.freedesktop.org Cc: <stable@vger.kernel.org> # v4.9+ Signed-off-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1484922525-6131-3-git-send-email-ander.conselvan.de.oliveira@intel.com (cherry picked from commit 46a1bd289507dfcc428fb9daf65421ed6be6af8b) Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2017-01-25drm/i915: Don't init hpd polling for vlv and chv from runtime_suspend()Ander Conselvan de Oliveira
An error in the condition for avoiding the call to intel_hpd_poll_init() for valleyview and cherryview from intel_runtime_suspend() caused it to be called unconditionally. Fix it. Fixes: 19625e85c6ec ("drm/i915: Enable polling when we don't have hpd") Cc: stable@vger.kernel.org Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Lyude <cpaul@redhat.com> Cc: Daniel Vetter <daniel.vetter@intel.com> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: intel-gfx@lists.freedesktop.org Cc: <stable@vger.kernel.org> # v4.9+ Signed-off-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1484922525-6131-2-git-send-email-ander.conselvan.de.oliveira@intel.com (cherry picked from commit 04313b00b79405f86d815100f85c47a2ee5b8ca0) Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2017-01-25drm/i915: Don't leak edid in intel_crt_detect_ddc()Ander Conselvan de Oliveira
In the path where intel_crt_detect_ddc() detects a CRT, if would return true without freeing the edid. Fixes: a2bd1f541f19 ("drm/i915: check whether we actually received an edid in detect_ddc") Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Daniel Vetter <daniel.vetter@intel.com> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: intel-gfx@lists.freedesktop.org Cc: <stable@vger.kernel.org> # v3.6+ Signed-off-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Reviewed-by: Jani Nikula <jani.nikula@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1484922525-6131-1-git-send-email-ander.conselvan.de.oliveira@intel.com (cherry picked from commit c96b63a6a7ac4bd670ec2e663793a9a31418b790) Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2017-01-25drm/i915: Release temporary load-detect state upon switchingChris Wilson
After we call drm_atomic_commit() on the load-detect state, we can free our local reference. Upon restore, we only apply and free the previous state. Fixes: 0853695c3ba4 ("drm: Add reference counting to drm_atomic_state") Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: <drm-intel-fixes@lists.freedesktop.org> # v4.10-rc1+ Link: http://patchwork.freedesktop.org/patch/msgid/20170119113749.2517-1-chris@chris-wilson.co.uk Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> (cherry picked from commit 7abbd11f344aa7abe29befb218774a1ea26018ac) Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2017-01-25drm/i915: prevent crash with .disable_display parameterClint Taylor
The .disable_display parameter was causing a fatal crash when fbdev was dereferenced during driver init. V1: protection in i915_drv.c V2: Moved protection to intel_fbdev.c Fixes: 43cee314345a ("drm/i915/fbdev: Limit the global async-domain synchronization") Testcase: igt/drv_module_reload/basic-no-display Cc: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Clint Taylor <clinton.a.taylor@intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1484775523-29428-1-git-send-email-clinton.a.taylor@intel.com Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Lukas Wunner <lukas@wunner.de> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: <stable@vger.kernel.org> # v4.8+ Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> (cherry picked from commit 5b8cd0755f8a06a851c436a013e7be0823fb155a) Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2017-01-25drm/i915: Avoid drm_atomic_state_put(NULL) in intel_display_resumeChris Wilson
intel_display_resume() may be called without an atomic state to restore, i.e. dev_priv->modeset_reset_restore state is NULL. One such case is following a lid open/close event and the forced modeset in intel_lid_notify(). Reported-by: Stefan Seyfried <stefan.seyfried@googlemail.com> Tested-by: Stefan Seyfried <stefan.seyfried@googlemail.com> Fixes: 0853695c3ba4 ("drm: Add reference counting to drm_atomic_state") Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Jani Nikula <jani.nikula@linux.intel.com> Cc: <drm-intel-fixes@lists.freedesktop.org> # v4.10-rc1+ Link: http://patchwork.freedesktop.org/patch/msgid/20170115125825.18597-1-chris@chris-wilson.co.uk Reviewed-by: Ander Conselvan de Oliveira <conselvan2@gmail.com> (cherry picked from commit 3c5e37f169cb67cbd03c6116fbc93e0805815d29) Signed-off-by: Jani Nikula <jani.nikula@intel.com>
2017-01-25dmaengine: pl330: fix double lockIago Abal
The static bug finder EBA (http://www.iagoabal.eu/eba/) reported the following double-lock bug: Double lock: 1. spin_lock_irqsave(pch->lock, flags) at pl330_free_chan_resources:2236; 2. call to function `pl330_release_channel' immediately after; 3. call to function `dma_pl330_rqcb' in line 1753; 4. spin_lock_irqsave(pch->lock, flags) at dma_pl330_rqcb:1505. I have fixed it as suggested by Marek Szyprowski. First, I have replaced `pch->lock' with `pl330->lock' in functions `pl330_alloc_chan_resources' and `pl330_free_chan_resources'. This avoids the double-lock by acquiring a different lock than `dma_pl330_rqcb'. NOTE that, as a result, `pl330_free_chan_resources' executes `list_splice_tail_init' on `pch->work_list' under lock `pl330->lock', whereas in the rest of the code `pch->work_list' is protected by `pch->lock'. I don't know if this may cause race conditions. Similarly `pch->cyclic' is written by `pl330_alloc_chan_resources' under `pl330->lock' but read by `pl330_tx_submit' under `pch->lock'. Second, I have removed locking from `pl330_request_channel' and `pl330_release_channel' functions. Function `pl330_request_channel' is only called from `pl330_alloc_chan_resources', so the lock is already held. Function `pl330_release_channel' is called from `pl330_free_chan_resources', which already holds the lock, and from `pl330_del'. Function `pl330_del' is called in an error path of `pl330_probe' and at the end of `pl330_remove', but I assume that there cannot be concurrent accesses to the protected data at those points. Signed-off-by: Iago Abal <mail@iagoabal.eu> Reviewed-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-01-25dmaengine: cppi41: Clean up pointless warningsTony Lindgren
With patches "dmaengine: cppi41: Fix runtime PM timeouts with USB mass storage", and "dmaengine: cppi41: Fix oops in cppi41_runtime_resume", the pm_runtime_get/put() in cppi41_irq() is no longer needed. We now guarantee that cppi41 is enabled when dma is in use. We can still get pointless error -115 when musb is configured as a usb peripheral. That's because we should now check for the state of is_suspended instead. Let's just remove the now useless code and replace it with a WARN(). Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-01-25dmaengine: cppi41: Fix oops in cppi41_runtime_resumeTony Lindgren
Commit fdea2d09b997 ("dmaengine: cppi41: Add basic PM runtime support") together with recent MUSB changes allowed USB and DMA on BeagleBone to idle when no cable is connected. But looks like few corner case issues still remain. Looks like just by re-plugging USB cable about ten or so times on BeagleBone when configured in USB peripheral mode we can get warnings and eventually trigger an oops in cppi41 DMA: WARNING: CPU: 0 PID: 14 at drivers/dma/cppi41.c:1154 cppi41_runtime_suspend+ x28/0x38 [cppi41] ... WARNING: CPU: 0 PID: 14 at drivers/dma/cppi41.c:452 push_desc_queue+0x94/0x9c [cppi41] ... Unable to handle kernel NULL pointer dereference at virtual address 00000104 pgd = c0004000 [00000104] *pgd=00000000 Internal error: Oops: 805 [#1] SMP ARM ... [<bf0d92cc>] (cppi41_runtime_resume [cppi41]) from [<c0589838>] (__rpm_callback+0xc0/0x214) [<c0589838>] (__rpm_callback) from [<c05899ac>] (rpm_callback+0x20/0x80) [<c05899ac>] (rpm_callback) from [<c0589460>] (rpm_resume+0x504/0x78c) [<c0589460>] (rpm_resume) from [<c058a1a0>] (pm_runtime_work+0x60/0xa8) [<c058a1a0>] (pm_runtime_work) from [<c0156120>] (process_one_work+0x2b4/0x808) This is because of a race with runtime PM and cppi41_dma_issue_pending() as reported by Alexandre Bailon <abailon@baylibre.com> in earlier set of patches. Based on mailing list discussions we however came to the conclusion that a different fix from Alexandre's fix is needed in order to guarantee that DMA is really active when we try to use it. To fix the issue, we need to add a driver specific flag as we otherwise can have -EINPROGRESS state set by runtime PM and can't rely on pm_runtime_active() to tell us when we can use the DMA. And we need to make sure the DMA transfers get triggered in the queued order. So let's always queue the transfers, then flush the queue from both cppi41_dma_issue_pending() and cppi41_runtime_resume() as suggested by Grygorii Strashko <grygorii.strashko@ti.com> in an earlier example patch. For reference, this is also documented in Documentation/power/runtime_pm.txt in the example at the end of the file as pointed out by Grygorii Strashko <grygorii.strashko@ti.com>. Based on earlier patches from Alexandre Bailon <abailon@baylibre.com> and Grygorii Strashko <grygorii.strashko@ti.com> modified based on testing and what was discussed on the mailing lists. Fixes: fdea2d09b997 ("dmaengine: cppi41: Add basic PM runtime support") Cc: Andy Shevchenko <andy.shevchenko@gmail.com> Cc: Bin Liu <b-liu@ti.com> Cc: Grygorii Strashko <grygorii.strashko@ti.com> Cc: Kevin Hilman <khilman@baylibre.com> Cc: Patrick Titiano <ptitiano@baylibre.com> Cc: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> Reported-by: Alexandre Bailon <abailon@baylibre.com> Signed-off-by: Tony Lindgren <tony@atomide.com> Tested-by: Bin Liu <b-liu@ti.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-01-25dmaengine: cppi41: Fix runtime PM timeouts with USB mass storageTony Lindgren
Commit fdea2d09b997 ("dmaengine: cppi41: Add basic PM runtime support") added runtime PM support for cppi41, but had corner case issues. Some of the issues were fixed with commit 098de42ad670 ("dmaengine: cppi41: Fix unpaired pm runtime when only a USB hub is connected"). That fix however caused a new regression where we can get error -115 messages with USB on BeagleBone when connecting a USB mass storage device to a hub. This is because when connecting a USB mass storage device to a hub, the initial DMA transfers can take over 200ms to complete and cppi41 autosuspend delay times out. To fix the issue, we want to implement refcounting for chan_busy array that contains the active dma transfers. Increasing the autosuspend delay won't help as that the delay could be potentially seconds, and it's best to let the USB subsystem to deal with the timeouts on errors. The earlier attempt for runtime PM was buggy as the pm_runtime_get/put() calls could get unpaired easily as they did not follow the state of the chan_busy array as described in commit 098de42ad670 ("dmaengine: cppi41: Fix unpaired pm runtime when only a USB hub is connected". Let's fix the issue by adding pm_runtime_get() to where a new transfer is added to the chan_busy array, and calls to pm_runtime_put() where chan_busy array entry is cleared. This prevents any autosuspend timeouts from happening while dma transfers are active. Fixes: 098de42ad670 ("dmaengine: cppi41: Fix unpaired pm runtime when only a USB hub is connected") Fixes: fdea2d09b997 ("dmaengine: cppi41: Add basic PM runtime support") Cc: Andy Shevchenko <andy.shevchenko@gmail.com> Cc: Bin Liu <b-liu@ti.com> Cc: Grygorii Strashko <grygorii.strashko@ti.com> Cc: Kevin Hilman <khilman@baylibre.com> Cc: Patrick Titiano <ptitiano@baylibre.com> Cc: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> Signed-off-by: Tony Lindgren <tony@atomide.com> Tested-by: Bin Liu <b-liu@ti.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2017-01-25drm/i915/gvt: Fix kmem_cache_create() nameAlex Williamson
According to kmem_cache_sanity_check(), spaces are not allowed in the name of a cache and results in a kernel oops with CONFIG_DEBUG_VM. Convert to underscores. Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
2017-01-25drm/i915/gvt/kvmgt: mdev ABI is available_instances, not available_instanceAlex Williamson
Per the ABI specification[1], each mdev_supported_types entry should have an available_instances, with an "s", not available_instance. [1] Documentation/ABI/testing/sysfs-bus-vfio-mdev Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
2017-01-25Revert "thermal: thermal_hwmon: Convert to hwmon_device_register_with_info()"Fabio Estevam
This reverts commit 7611fb68062f ("thermal: thermal_hwmon: Convert to hwmon_device_register_with_info()"). Pavel Machek reported breakage in the Nokia N900 due to this commit. We can revisit a proper fix for the warning later. Reported-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com> Acked-by: Guenter Roeck <linux@roeck-us.net> Acked-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Zhang Rui <rui.zhang@intel.com>
2017-01-24Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge fixes from Andrew Morton: "26 fixes" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (26 commits) MAINTAINERS: add Dan Streetman to zbud maintainers MAINTAINERS: add Dan Streetman to zswap maintainers mm: do not export ioremap_page_range symbol for external module mn10300: fix build error of missing fpu_save() romfs: use different way to generate fsid for BLOCK or MTD frv: add missing atomic64 operations mm, page_alloc: fix premature OOM when racing with cpuset mems update mm, page_alloc: move cpuset seqcount checking to slowpath mm, page_alloc: fix fast-path race with cpuset update or removal mm, page_alloc: fix check for NULL preferred_zone kernel/panic.c: add missing \n fbdev: color map copying bounds checking frv: add atomic64_add_unless() mm/mempolicy.c: do not put mempolicy before using its nodemask radix-tree: fix private list warnings Documentation/filesystems/proc.txt: add VmPin mm, memcg: do not retry precharge charges proc: add a schedule point in proc_pid_readdir() mm: alloc_contig: re-allow CMA to compact FS pages mm/slub.c: trace free objects at KERN_INFO ...
2017-01-24fbdev: color map copying bounds checkingKees Cook
Copying color maps to userspace doesn't check the value of to->start, which will cause kernel heap buffer OOB read due to signedness wraps. CVE-2016-8405 Link: http://lkml.kernel.org/r/20170105224249.GA50925@beast Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Kees Cook <keescook@chromium.org> Reported-by: Peter Pi (@heisecode) of Trend Micro Cc: Min Chong <mchong@google.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-01-24drivers/memstick/core/memstick.c: avoid -Wnonnull warningArnd Bergmann
gcc-7 produces a harmless false-postive warning about a possible NULL pointer access: drivers/memstick/core/memstick.c: In function 'h_memstick_read_dev_id': drivers/memstick/core/memstick.c:309:3: error: argument 2 null where non-null expected [-Werror=nonnull] memcpy(mrq->data, buf, mrq->data_len); This can't happen because the caller sets the command to 'MS_TPC_READ_REG', which causes the data direction to be 'READ' and the NULL pointer not accessed. As a simple workaround for the warning, we can pass a pointer to the data that we actually want to read into. This is not needed here, but also harmless, and lets the compiler know that the access is ok. Link: http://lkml.kernel.org/r/20170111144143.548867-1-arnd@arndb.de Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Alex Dubov <oakad@yahoo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>