- 09 Dec, 2016 3 commits
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Ping Cheng authored
Make sure everything reported from pad are registered Signed-off-by: Ping Cheng <ping.cheng@wacom.com> Reviewed-By: Jason Gerecke <jason.gerecke@wacom.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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Ping Cheng authored
Sometime valid events may not be supported by the driver yet. Make sure we don't process them when the code is not ready. This fix prevents a kernel panic due to unsupported HID events. Signed-off-by: Ping Cheng <ping.cheng@wacom.com> Reviewed-By: Jason Gerecke <jason.gerecke@wacom.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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Ping Cheng authored
It is unnecessary to return a value since nothing is expecting a value from it. Signed-off-by: Ping Cheng <ping.cheng@wacom.com> Reviewed-By: Jason Gerecke <jason.gerecke@wacom.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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- 15 Nov, 2016 2 commits
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Jason Gerecke authored
The eraser end of the 8K pen available for the MobileStudio Pro has a tool ID of 0x84a. The 'wacom_intuos_get_tool_type' function does not currently recognize this ID, causing it to return BTN_TOOL_PEN rather than BTN_TOOL_RUBBER. This does not cause a problem for the MobileStudio Pro since, as a HID_GENERIC device, the driver relies on the state of the HID_DG_INVERT usage instead. It would, however, cause problems if the pen is used with devices that use the traditional 'wacom_intuos_irq' codepath instead. Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com> Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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Dan Carpenter authored
This is trying to clear the lower 32 bits but the type is wrong so it clears everything. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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- 20 Oct, 2016 18 commits
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Jason Gerecke authored
The "Steering" usage (HID_UP_SIMULATION | 0xc8) is defined in HUT 1.12 as follows: "A steering wheel is a single degree-of-freedom device that rotates about an axis. The zero position is always the neutral or 'straight ahead' position, with positive values turning clockwise and negative values turning counterclockwise. If the Coordinate Values Wrap attribute is set, the steering wheel can be turned past 360 degrees." The hidinput_configure_usage function canonically maps this usage to the ABS_WHEEL axis, but hidinput_calc_abs_res does not recognize this axis as one for which it can calculate a resolution. This effectively prevents wheels from being assigned a proper resolution that userspace can use to determine the precise angle of input. This commit adds ABS_WHEEL as a rotational axis to hidinput_calc_abs_res. Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com> Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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Jason Gerecke authored
The HID specification that the MobileStudio Pro follows includes usages for several values that would be good to support so that future devices "just work" out of the box. Extend the HID_GENERIC pad codepath to handle these usages. Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com> Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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Jason Gerecke authored
Adds support for usages that may appear on the pen or pad interface which report the state of the tablet battery. Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com> Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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Jason Gerecke authored
As with usages for the pen, the Custom HID specificiation includes usages for the pad. Here we add functions to map and handle most of the pad usages present on the MobileStudio Pro. Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com> Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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Jason Gerecke authored
Many of Wacom's display tablets include an "outbound" area where pen digitizing is possible but outside of the display area. To accommodate such sensors in the HID_GENERIC codepath, we add support for the necessary vendor-defined HID feature usages and adjust the min/max values of the X and Y axes accordingly, similar to what is done in the non-generic codepath. Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com> Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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Jason Gerecke authored
Many of Wacom's display tablets include an "outbound" area where pen digitizing is possible but outside of the display area. To ensure that pen coordinates are mapped to the correct on-screen location, the driver sets the minimum and maximum axis values of X and Y to those coordinates which coincide with the screen edge. These values are simply the hardware minimum/maximum plus/minus the outbound size for a particular edge. When outbound support was added/updated in ac414da3, fa770340, and ecd618dc, we decided to have the wacom_features structs store the desired minimum and maximum values directly. In hindsight, this was perhaps not the best choice since it has allowed minor errors to crop up unnoticed. Some tablets have had their coordinates over-corrected (e.g. most of the devices "fixed" in ecd618dc were already adjusted in ac414da3), while others never had a correction applied (e.g. the ISDv5 325, whose declared maximum the hardware maximum instead of the outbound maximum). A less error-prone method of handling the outbound is to let the driver calculate the correct minimum/maximum values by providing it with both the actual hardware maximums and the size of the outbound on each edge. These values are more easy to verify as correct since the values can be trivially compared against specifications. This patch reverts the declared maximum values to the actual hardware maximums, e.g. as declared prior to ac414da3 (values for these and other display tablets that were subsuquently introduced have been verified against specs). Per-edge outbound sizes are stored in the wacom_features struct as offset_{left,right,top,bottom} and used in combination with the hardware ranges to calculate effective axis ranges for ABS_X and ABS_Y. Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com> Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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Jason Gerecke authored
Devices following the new Custom HID mode specification (as well as even some recent component sensors which use the same standard HID usage) are capable of reporting tool ID information that we need to relay to userspace. This patch adds support for reading and relaying the tool type information, which is (unfortunately) split across two usages. We also advertise the existence of tool types beyond BTN_TOOL_PEN that might be available. Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com> Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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Jason Gerecke authored
The 'wacom_intuos_inout' function incorrectly assmebles tool IDs from the proximity report, shifting the higher values of the ID four bits farther than intended. This problem was not detected until too late, but has not caused any issues since the incorrect IDs still fit in a 32-bit integer and userspace programs have not required the value to match the hardware (just that the values are unique and constant). The tool IDs reported by the new MobileStudio Pro (or any future HID_GENERIC device that supports them) do not suffer from the same assembly issue, however. In order for 'wacom_intuos_get_tool_type' to work for with both codepaths, we correct this issue internally and have 'wacom_intuos_general' only mangle the ID when it is posted to userspace. Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com> Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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Jason Gerecke authored
Wacom's professional tablets beginning with the Intuos4 are capable of reporting an intermediate degree of proximity where the pen is no longer close enough to communicate with ("in prox"), but still close enough to be sensed ("in range"). This additional state is particularly useful for performing palm rejection as it allows the driver to disable the touch sensor while the pen is a greater distance from the tablet. Like other professional tablets, the new MobileStudio Pro also reports this intermeidate "in range" proximity state. Its descriptor assigns usage 0xff0d0036 to this bit. Normally 'wacom_equivalent_usage' would translate this to the standard HID "Quality" usage, but since this has a different meaning we have it explicitly ignore the usage and define it ourselves as "Sense" (since "In Range" is already defined by the HID standard and interpreted by our driver as meaning "in prox"). Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com> Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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Jason Gerecke authored
The airbrush fingerwheel does not have a usage that corresponds cleanly with a standard HID usage, so we add explicit support for it via its vendor-defined usage. Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com> Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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Jason Gerecke authored
The vendor-defined 0xFF0D01032 ("Distance") usage is nearly equivalent to HID_GD_Z, except that the axis direction is inverted. Unlike HID_GD_Z which increases in value as the pen-to-surface distance is decreased, this usage decreases. Treat this usage as a special case to ensure we don't invert the scale to be ABS_DISTANCE compatible like we do for HID_GD_Z. Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com> Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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Jason Gerecke authored
Wacom's new "MobileStudio Pro" tablets are the first devices in their branded product line-up to include a usable HID descriptor for the pen interface. Like prior branded products, the device can operate in one of two modes: 'Standard HID', and 'Wacom Custom HID'. Although the first mode is usable by the HID_GENERIC codepath as-is (huzzah!), it is subject to some restrictions -- most notably pressure being limited to 2048 levels instead of 8192. To ensure tablets that include support for Custom HID mode work optimally, we add support for its usages and switch the device to Custom HID mode if possible. The usages defined for Custom HID mode are often numerically similar to their standard HID equivalents, allowing us to write a simple translation function that takes arbitrary HID usages as input and which returns the corresponding standard HID usage as output (if one exists). Switching on this translated usage instead of the actual usage allows the existing cases to apply to both modes of operation without having to explicitly define every Custom HID usage. Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com> Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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Jason Gerecke authored
The HID standard defines usages that allow digitizers to report the pen's height, tilt, and rotation and which are used by Wacom's new "MobileStudio Pro" devices. Note that 'hidinput_calc_abs_res' expects ABS_Z (historically used by our driver to report twist) to have linear units. To ensure it calculates a resolution with the actually-angular units provided in the HID descriptor we nedd to lie and tell it we're calculating it for the (rotational) ABS_RZ axis instead. Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com> Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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Jason Gerecke authored
The product name received from the string descriptor in the new MobileStudio Pro line of tablets begins with "Wacom", which leads to unnecessary visual noise in the device name when appended to the vendor name which also includes "Wacom". Look for and fix cases like this. Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com> Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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Jason Gerecke authored
ISDv4 devices have long supported reporting data from each of two barrel switches, but HID_DG_BARRELSWITCH2 itself was only recently standardized. Prior to its adoption, ISDv4 devices would associate the bit indicating the state of the second barrel switch with the "Undefined" 0x000D0000 usage. Although most such devices have explicit support, a few use the HID_GENERIC codepath which ignores the "Undefined" usage. This patch adds code which detects the presence of a pre-standard second barrel switch and corrects the usage value so that the HID_GENERIC code will declare its presence and report its state. Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com> Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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Jason Gerecke authored
This just centralizes the logic used in both wacom_setup_numbered_buttons and wacom_report_numbered_buttons so that they don't drift out of sync. Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com> Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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Jason Gerecke authored
We've defined several new usages (e.g. WACOM_G9_PEN and WACOM_G9_TOUCHSCREEN) which aren't checked by the WACOM_PEN_FIELD and WACOM_FINGER_FIELD macros but probably should be. Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com> Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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Jason Gerecke authored
Our loose use of "pen" and "digitizer" in the naming of several of our vendor-defined usages may be a source of confusion given that the terms have specific meaning within the HID specification. "Pen" specifically refers to "an integrated display that allows the use of a stylus" (e.g. something like a tablet PC or Cintiq) wheras "Digitizer" is a better fit for opaque tablets like an Intuos. While we're at it, go ahead and rename the definitions to make them more distinct and better match up with the convention used by HID (e.g. the use of '_UP_' for usage pages) and make them more distinct. Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com> Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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- 19 Oct, 2016 11 commits
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git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hidLinus Torvalds authored
Pull HID fixes from Jiri Kosina: - hid-dr regression fix for certain dragonrise gamepads (device ID 0079:0006), from Ioan-Adrian Ratiu - dma-on-stack fix for hid-led driver, from Heiner Kallweit - quirk for Akai MIDImix device * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid: HID: add quirk for Akai MIDImix. Revert "HID: dragonrise: fix HID Descriptor for 0x0006 PID" HID: hid-dr: add input mapping for axis selection HID: hid-led: fix issue with transfer buffer not being dma capable
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git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrlLinus Torvalds authored
Pull first round of pin control fixes from Linus Walleij: - a bunch of barnsjukdomar/kinderkrankheiten/maladie infantile in the Aspeed driver. (Why doesn't English have a word for this?) [ Maybe "teething problems" is the closest English idiom? - Linus T ] - fix a lockdep bug on the Intel BayTrail. - fix a few special laptop issues on the Intel pin controller solving suspend issues. * tag 'pinctrl-v4.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: pinctrl: intel: Only restore pins that are used by the driver pinctrl: baytrail: Fix lockdep pinctrl: aspeed-g5: Fix pin association of SPI1 function pinctrl: aspeed-g5: Fix GPIOE1 typo pinctrl: aspeed-g5: Fix names of GPID2 pins pinctrl: aspeed: "Not enabled" is a significant mux state
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Linus Torvalds authored
We have a fairly common pattern where you print several things as continuations on one single line in a loop, and then at the end you do printk(KERN_CONT "\n"); to flush the buffered output. But if the output was flushed by something else (concurrent printk activity, or just system logging), we don't want that final flushing to just print an empty line. So just suppress empty continuation lines when they couldn't be merged into the line they are a continuation of. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Linus Torvalds authored
Merge the gup_flags cleanups from Lorenzo Stoakes: "This patch series adjusts functions in the get_user_pages* family such that desired FOLL_* flags are passed as an argument rather than implied by flags. The purpose of this change is to make the use of FOLL_FORCE explicit so it is easier to grep for and clearer to callers that this flag is being used. The use of FOLL_FORCE is an issue as it overrides missing VM_READ/VM_WRITE flags for the VMA whose pages we are reading from/writing to, which can result in surprising behaviour. The patch series came out of the discussion around commit 38e08854 ("mm: check VMA flags to avoid invalid PROT_NONE NUMA balancing"), which addressed a BUG_ON() being triggered when a page was faulted in with PROT_NONE set but having been overridden by FOLL_FORCE. do_numa_page() was run on the assumption the page _must_ be one marked for NUMA node migration as an actual PROT_NONE page would have been dealt with prior to this code path, however FOLL_FORCE introduced a situation where this assumption did not hold. See https://marc.info/?l=linux-mm&m=147585445805166 for the patch proposal" Additionally, there's a fix for an ancient bug related to FOLL_FORCE and FOLL_WRITE by me. [ This branch was rebased recently to add a few more acked-by's and reviewed-by's ] * gup_flag-cleanups: mm: replace access_process_vm() write parameter with gup_flags mm: replace access_remote_vm() write parameter with gup_flags mm: replace __access_remote_vm() write parameter with gup_flags mm: replace get_user_pages_remote() write/force parameters with gup_flags mm: replace get_user_pages() write/force parameters with gup_flags mm: replace get_vaddr_frames() write/force parameters with gup_flags mm: replace get_user_pages_locked() write/force parameters with gup_flags mm: replace get_user_pages_unlocked() write/force parameters with gup_flags mm: remove write/force parameters from __get_user_pages_unlocked() mm: remove write/force parameters from __get_user_pages_locked() mm: remove gup_flags FOLL_WRITE games from __get_user_pages()
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Lorenzo Stoakes authored
This removes the 'write' argument from access_process_vm() and replaces it with 'gup_flags' as use of this function previously silently implied FOLL_FORCE, whereas after this patch callers explicitly pass this flag. We make this explicit as use of FOLL_FORCE can result in surprising behaviour (and hence bugs) within the mm subsystem. Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com> Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Lorenzo Stoakes authored
This removes the 'write' argument from access_remote_vm() and replaces it with 'gup_flags' as use of this function previously silently implied FOLL_FORCE, whereas after this patch callers explicitly pass this flag. We make this explicit as use of FOLL_FORCE can result in surprising behaviour (and hence bugs) within the mm subsystem. Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Lorenzo Stoakes authored
This removes the 'write' argument from __access_remote_vm() and replaces it with 'gup_flags' as use of this function previously silently implied FOLL_FORCE, whereas after this patch callers explicitly pass this flag. We make this explicit as use of FOLL_FORCE can result in surprising behaviour (and hence bugs) within the mm subsystem. Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Lorenzo Stoakes authored
This removes the 'write' and 'force' from get_user_pages_remote() and replaces them with 'gup_flags' to make the use of FOLL_FORCE explicit in callers as use of this flag can result in surprising behaviour (and hence bugs) within the mm subsystem. Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Lorenzo Stoakes authored
This removes the 'write' and 'force' from get_user_pages() and replaces them with 'gup_flags' to make the use of FOLL_FORCE explicit in callers as use of this flag can result in surprising behaviour (and hence bugs) within the mm subsystem. Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com> Acked-by: Christian König <christian.koenig@amd.com> Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Lorenzo Stoakes authored
This removes the 'write' and 'force' from get_vaddr_frames() and replaces them with 'gup_flags' to make the use of FOLL_FORCE explicit in callers as use of this flag can result in surprising behaviour (and hence bugs) within the mm subsystem. Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Lorenzo Stoakes authored
This removes the 'write' and 'force' use from get_user_pages_locked() and replaces them with 'gup_flags' to make the use of FOLL_FORCE explicit in callers as use of this flag can result in surprising behaviour (and hence bugs) within the mm subsystem. Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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- 18 Oct, 2016 6 commits
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git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fsLinus Torvalds authored
Pull f2fs bugfix from Jaegeuk Kim: "This fixes a bug which referenced the wrong pointer, sum_page, in f2fs_gc. It was newly introduced in 4.9-rc1. * tag 'for-f2fs-4.9-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: f2fs: fix wrong sum_page pointer in f2fs_gc
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Lorenzo Stoakes authored
This removes the 'write' and 'force' use from get_user_pages_unlocked() and replaces them with 'gup_flags' to make the use of FOLL_FORCE explicit in callers as use of this flag can result in surprising behaviour (and hence bugs) within the mm subsystem. Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com> Reviewed-by: Jan Kara <jack@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Lorenzo Stoakes authored
This removes the redundant 'write' and 'force' parameters from __get_user_pages_unlocked() to make the use of FOLL_FORCE explicit in callers as use of this flag can result in surprising behaviour (and hence bugs) within the mm subsystem. Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Jan Kara <jack@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Lorenzo Stoakes authored
This removes the redundant 'write' and 'force' parameters from __get_user_pages_locked() to make the use of FOLL_FORCE explicit in callers as use of this flag can result in surprising behaviour (and hence bugs) within the mm subsystem. Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com> Reviewed-by: Jan Kara <jack@suse.cz> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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Linus Torvalds authored
This is an ancient bug that was actually attempted to be fixed once (badly) by me eleven years ago in commit 4ceb5db9 ("Fix get_user_pages() race for write access") but that was then undone due to problems on s390 by commit f33ea7f4 ("fix get_user_pages bug"). In the meantime, the s390 situation has long been fixed, and we can now fix it by checking the pte_dirty() bit properly (and do it better). The s390 dirty bit was implemented in abf09bed ("s390/mm: implement software dirty bits") which made it into v3.9. Earlier kernels will have to look at the page state itself. Also, the VM has become more scalable, and what used a purely theoretical race back then has become easier to trigger. To fix it, we introduce a new internal FOLL_COW flag to mark the "yes, we already did a COW" rather than play racy games with FOLL_WRITE that is very fundamental, and then use the pte dirty flag to validate that the FOLL_COW flag is still valid. Reported-and-tested-by: Phil "not Paul" Oester <kernel@linuxace.com> Acked-by: Hugh Dickins <hughd@google.com> Reviewed-by: Michal Hocko <mhocko@suse.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Kees Cook <keescook@chromium.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Nick Piggin <npiggin@gmail.com> Cc: Greg Thelen <gthelen@google.com> Cc: stable@vger.kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull x86 fixes from Ingo Molnar: "Misc fixes, plus hw-enablement changes: - fix persistent RAM handling - remove pkeys warning - remove duplicate macro - fix debug warning in irq handler - add new 'Knights Mill' CPU related constants and enable the perf bits" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf/x86/intel/uncore: Add Knights Mill CPUID perf/x86/intel/rapl: Add Knights Mill CPUID perf/x86/intel: Add Knights Mill CPUID x86/cpu/intel: Add Knights Mill to Intel family x86/e820: Don't merge consecutive E820_PRAM ranges pkeys: Remove easily triggered WARN x86: Remove duplicate rtit status MSR macro x86/smp: Add irq_enter/exit() in smp_reschedule_interrupt()
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