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* Merge tag 'drm-x86-pat-regression-fix' of ↵Linus Torvalds2016-10-281-0/+22
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://people.freedesktop.org/~airlied/linux Pull drm x86/pat regression fixes from Dave Airlie: "This is a standalone pull request for the fix for a regression introduced in -rc1 by a change to vm_insert_mixed to start using the PAT range tracking to validate page protections. With this fix in place, all the VRAM mappings for GPU drivers ended up at UC instead of WC. There are probably better ways to fix this long term, but nothing I'd considered for -fixes that wouldn't need more settling in time. So I've just created a new arch API that the drivers can reserve all their VRAM aperture ranges as WC" * tag 'drm-x86-pat-regression-fix' of git://people.freedesktop.org/~airlied/linux: drm/drivers: add support for using the arch wc mapping API. x86/io: add interface to reserve io memtype for a resource range. (v1.1)
| * x86/io: add interface to reserve io memtype for a resource range. (v1.1)Dave Airlie2016-10-261-0/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A recent change to the mm code in: 87744ab3832b mm: fix cache mode tracking in vm_insert_mixed() started enforcing checking the memory type against the registered list for amixed pfn insertion mappings. It happens that the drm drivers for a number of gpus relied on this being broken. Currently the driver only inserted VRAM mappings into the tracking table when they came from the kernel, and userspace mappings never landed in the table. This led to a regression where all the mapping end up as UC instead of WC now. I've considered a number of solutions but since this needs to be fixed in fixes and not next, and some of the solutions were going to introduce overhead that hadn't been there before I didn't consider them viable at this stage. These mainly concerned hooking into the TTM io reserve APIs, but these API have a bunch of fast paths I didn't want to unwind to add this to. The solution I've decided on is to add a new API like the arch_phys_wc APIs (these would have worked but wc_del didn't take a range), and use them from the drivers to add a WC compatible mapping to the table for all VRAM on those GPUs. This means we can then create userspace mapping that won't get degraded to UC. v1.1: use CONFIG_X86_PAT + add some comments in io.h Cc: Toshi Kani <toshi.kani@hp.com> Cc: Borislav Petkov <bp@alien8.de> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Brian Gerst <brgerst@gmail.com> Cc: x86@kernel.org Cc: mcgrof@suse.com Cc: Dan Williams <dan.j.williams@intel.com> Acked-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Dave Airlie <airlied@redhat.com>
* | Merge branch 'akpm' (patches from Andrew)Linus Torvalds2016-10-272-4/+3
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge misc fixes from Andrew Morton: "20 fixes" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: drivers/misc/sgi-gru/grumain.c: remove bogus 0x prefix from printk cris/arch-v32: cryptocop: print a hex number after a 0x prefix ipack: print a hex number after a 0x prefix block: DAC960: print a hex number after a 0x prefix fs: exofs: print a hex number after a 0x prefix lib/genalloc.c: start search from start of chunk mm: memcontrol: do not recurse in direct reclaim CREDITS: update credit information for Martin Kepplinger proc: fix NULL dereference when reading /proc/<pid>/auxv mm: kmemleak: ensure that the task stack is not freed during scanning lib/stackdepot.c: bump stackdepot capacity from 16MB to 128MB latent_entropy: raise CONFIG_FRAME_WARN by default kconfig.h: remove config_enabled() macro ipc: account for kmem usage on mqueue and msg mm/slab: improve performance of gathering slabinfo stats mm: page_alloc: use KERN_CONT where appropriate mm/list_lru.c: avoid error-path NULL pointer deref h8300: fix syscall restarting kcov: properly check if we are in an interrupt mm/slab: fix kmemcg cache creation delayed issue
| * | kconfig.h: remove config_enabled() macroMasahiro Yamada2016-10-272-4/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The use of config_enabled() is ambiguous. For config options, IS_ENABLED(), IS_REACHABLE(), etc. will make intention clearer. Sometimes config_enabled() has been used for non-config options because it is useful to check whether the given symbol is defined or not. I have been tackling on deprecating config_enabled(), and now is the time to finish this work. Some new users have appeared for v4.9-rc1, but it is trivial to replace them: - arch/x86/mm/kaslr.c replace config_enabled() with IS_ENABLED() because CONFIG_X86_ESPFIX64 and CONFIG_EFI are boolean. - include/asm-generic/export.h replace config_enabled() with __is_defined(). Then, config_enabled() can be removed now. Going forward, please use IS_ENABLED(), IS_REACHABLE(), etc. for config options, and __is_defined() for non-config symbols. Link: http://lkml.kernel.org/r/1476616078-32252-1-git-send-email-yamada.masahiro@socionext.com Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Acked-by: Ingo Molnar <mingo@kernel.org> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org> Cc: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Kees Cook <keescook@chromium.org> Cc: Michal Marek <mmarek@suse.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Thomas Garnier <thgarnie@google.com> Cc: Paul Bolle <pebolle@tiscali.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | Merge tag 'xfs-fixes-for-linus-4.9-rc3' of ↵Linus Torvalds2016-10-271-6/+11
|\ \ \ | |/ / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs Pull xfs fixes from Dave Chinner: "This update contains fixes for most of the outstanding regressions introduced with the 4.9-rc1 XFS merge. There is also a fix for an iomap bug, too. This is a quite a bit larger than I'd prefer for a -rc3, but most of the change comes from cleaning up the new reflink copy on write code; it's much simpler and easier to understand now. These changes fixed several bugs in the new code, and it wasn't clear that there was an easier/simpler way to fix them. The rest of the fixes are the usual size you'd expect at this stage. I've left the commits to soak in linux-next for a some extra time because of the size before asking you to pull, no new problems with them have been reported so I think it's all OK. Summary: - iomap page offset masking fix for page faults - add IOMAP_REPORT to distinguish between read and fiemap map requests - cleanups to new shared data extent code - fix mount active status on failed log recovery - fix broken dquots in a buffer calculation - fix locking order issues and merge xfs_reflink_remap_range and xfs_file_share_range - rework unmapping of CoW extents and remove now unused functions - clean state when CoW is done" * tag 'xfs-fixes-for-linus-4.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs: (25 commits) xfs: clear cowblocks tag when cow fork is emptied xfs: fix up inode cowblocks tracking tracepoints fs: Do to trim high file position bits in iomap_page_mkwrite_actor xfs: remove xfs_bunmapi_cow xfs: optimize xfs_reflink_end_cow xfs: optimize xfs_reflink_cancel_cow_blocks xfs: refactor xfs_bunmapi_cow xfs: optimize writes to reflink files xfs: don't bother looking at the refcount tree for reads xfs: handle "raw" delayed extents xfs_reflink_trim_around_shared xfs: add xfs_trim_extent iomap: add IOMAP_REPORT xfs: merge xfs_reflink_remap_range and xfs_file_share_range xfs: remove xfs_file_wait_for_io xfs: move inode locking from xfs_reflink_remap_range to xfs_file_share_range xfs: fix the same_inode check in xfs_file_share_range xfs: remove the same fs check from xfs_file_share_range libxfs: v3 inodes are only valid on crc-enabled filesystems libxfs: clean up _calc_dquots_per_chunk xfs: unset MS_ACTIVE if mount fails ...
| * | iomap: add IOMAP_REPORTChristoph Hellwig2016-10-201-6/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This allows the file system to tell a FIEMAP from a read operation, and thus avoids the need to report flags that aren't actually used in the read path. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
* | | mm: remove per-zone hashtable of bitlock waitqueuesLinus Torvalds2016-10-271-28/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The per-zone waitqueues exist because of a scalability issue with the page waitqueues on some NUMA machines, but it turns out that they hurt normal loads, and now with the vmalloced stacks they also end up breaking gfs2 that uses a bit_wait on a stack object: wait_on_bit(&gh->gh_iflags, HIF_WAIT, TASK_UNINTERRUPTIBLE) where 'gh' can be a reference to the local variable 'mount_gh' on the stack of fill_super(). The reason the per-zone hash table breaks for this case is that there is no "zone" for virtual allocations, and trying to look up the physical page to get at it will fail (with a BUG_ON()). It turns out that I actually complained to the mm people about the per-zone hash table for another reason just a month ago: the zone lookup also hurts the regular use of "unlock_page()" a lot, because the zone lookup ends up forcing several unnecessary cache misses and generates horrible code. As part of that earlier discussion, we had a much better solution for the NUMA scalability issue - by just making the page lock have a separate contention bit, the waitqueue doesn't even have to be looked at for the normal case. Peter Zijlstra already has a patch for that, but let's see if anybody even notices. In the meantime, let's fix the actual gfs2 breakage by simplifying the bitlock waitqueues and removing the per-zone issue. Reported-by: Andreas Gruenbacher <agruenba@redhat.com> Tested-by: Bob Peterson <rpeterso@redhat.com> Acked-by: Mel Gorman <mgorman@techsingularity.net> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Steven Whitehouse <swhiteho@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | Merge tag 'clk-fixes-for-linus' of ↵Linus Torvalds2016-10-241-1/+1
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux Pull clk fixes from Stephen Boyd: "This is the first batch of clk driver fixes for this release. We have a handful of fixes for the uniphier clk driver that was introduced recently, as well as Kconfig option hiding, module autoloading markings, and a few fixes for clk_hw based registration patches that went in this merge window" * tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux: clk: at91: Fix a return value in case of error clk: uniphier: rename MIO clock to SD clock for Pro5, PXs2, LD20 SoCs clk: uniphier: fix memory overrun bug clk: hi6220: use CLK_OF_DECLARE_DRIVER for sysctrl and mediactrl clock init clk: mvebu: armada-37xx-periph: Fix the clock gate flag clk: bcm2835: Clamp the PLL's requested rate to the hardware limits. clk: max77686: fix number of clocks setup for clk_hw based registration clk: mvebu: armada-37xx-periph: Fix the clock provider registration clk: core: add __init decoration for CLK_OF_DECLARE_DRIVER function clk: mediatek: Add hardware dependency clk: samsung: clk-exynos-audss: Fix module autoload clk: uniphier: fix type of variable passed to regmap_read() clk: uniphier: add system clock support for sLD3 SoC
| * | | clk: core: add __init decoration for CLK_OF_DECLARE_DRIVER functionShawn Guo2016-10-171-1/+1
| |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The new introduced macro CLK_OF_DECLARE_DRIVER is usually used to declare clock driver init functions, which are mostly decorated with __init. Add __init decoration for CLK_OF_DECLARE_DRIVER function to avoid causing section mismatch warnings on client clock drivers. Signed-off-by: Shawn Guo <shawn.guo@linaro.org> Fixes: c7296c51ce5d ("clk: core: New macro CLK_OF_DECLARE_DRIVER") Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
* | / mm: unexport __get_user_pages()Lorenzo Stoakes2016-10-241-4/+0
| |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch unexports the low-level __get_user_pages() function. Recent refactoring of the get_user_pages* functions allow flags to be passed through get_user_pages() which eliminates the need for access to this function from its one user, kvm. We can see that the two calls to get_user_pages() which replace __get_user_pages() in kvm_main.c are equivalent by examining their call stacks: get_user_page_nowait(): get_user_pages(start, 1, flags, page, NULL) __get_user_pages_locked(current, current->mm, start, 1, page, NULL, NULL, false, flags | FOLL_TOUCH) __get_user_pages(current, current->mm, start, 1, flags | FOLL_TOUCH | FOLL_GET, page, NULL, NULL) check_user_page_hwpoison(): get_user_pages(addr, 1, flags, NULL, NULL) __get_user_pages_locked(current, current->mm, addr, 1, NULL, NULL, NULL, false, flags | FOLL_TOUCH) __get_user_pages(current, current->mm, addr, 1, flags | FOLL_TOUCH, NULL, NULL, NULL) Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Merge git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pendingLinus Torvalds2016-10-231-0/+1
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull SCSI target fixes from Nicholas Bellinger: "Here are the outstanding target-pending fixes for v4.9-rc2. This includes: - Fix v4.1.y+ reference leak regression with concurrent TMR ABORT_TASK + session shutdown. (Vaibhav Tandon) - Enable tcm_fc w/ SCF_USE_CPUID to avoid host exchange timeouts (Hannes) - target/user error sense handling fixes. (Andy + MNC + HCH) - Fix iscsi-target NOP_OUT error path iscsi_cmd descriptor leak (Varun) - Two EXTENDED_COPY SCSI status fixes for ESX VAAI (Dinesh Israni + Nixon Vincent) - Revert a v4.8 residual overflow change, that breaks sg_inq with small allocation lengths. There are a number of folks stress testing the v4.1.y regression fix in their environments, and more folks doing iser-target I/O stress testing atop recent v4.x.y code. There is also one v4.2.y+ RCU conversion regression related to explicit NodeACL configfs changes, that is still being tracked down" * git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: target/tcm_fc: use CPU affinity for responses target/tcm_fc: Update debugging statements to match libfc usage target/tcm_fc: return detailed error in ft_sess_create() target/tcm_fc: print command pointer in debug message target: fix potential race window in target_sess_cmd_list_waiting() Revert "target: Fix residual overflow handling in target_complete_cmd_with_length" target: Don't override EXTENDED_COPY xcopy_pt_cmd SCSI status code target: Make EXTENDED_COPY 0xe4 failure return COPY TARGET DEVICE NOT REACHABLE target: Re-add missing SCF_ACK_KREF assignment in v4.1.y iscsi-target: fix iscsi cmd leak iscsi-target: fix spelling mistake "Unsolicitied" -> "Unsolicited" target/user: Fix comments to not refer to data ring target/user: Return an error if cmd data size is too large target/user: Use sense_reason_t in tcmu_queue_cmd_ring
| * | target: Make EXTENDED_COPY 0xe4 failure return COPY TARGET DEVICE NOT REACHABLENicholas Bellinger2016-10-191-0/+1
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch addresses a bug where EXTENDED_COPY across multiple LUNs results in a CHECK_CONDITION when the source + destination are not located on the same physical node. ESX Host environments expect sense COPY_ABORTED w/ COPY TARGET DEVICE NOT REACHABLE to be returned when this occurs, in order to signal fallback to local copy method. As described in section 6.3.3 of spc4r22: "If it is not possible to complete processing of a segment because the copy manager is unable to establish communications with a copy target device, because the copy target device does not respond to INQUIRY, or because the data returned in response to INQUIRY indicates an unsupported logical unit, then the EXTENDED COPY command shall be terminated with CHECK CONDITION status, with the sense key set to COPY ABORTED, and the additional sense code set to COPY TARGET DEVICE NOT REACHABLE." Tested on v4.1.y with ESX v5.5u2+ with BlockCopy across multiple nodes. Reported-by: Nixon Vincent <nixon.vincent@calsoftinc.com> Tested-by: Nixon Vincent <nixon.vincent@calsoftinc.com> Cc: Nixon Vincent <nixon.vincent@calsoftinc.com> Tested-by: Dinesh Israni <ddi@datera.io> Signed-off-by: Dinesh Israni <ddi@datera.io> Cc: Dinesh Israni <ddi@datera.io> Cc: stable@vger.kernel.org # 3.14+ Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
* | Merge tag 'for-linus-4.9-2' of git://git.code.sf.net/p/openipmi/linux-ipmiLinus Torvalds2016-10-232-0/+19
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull IPMI updates from Corey Minyard: "A small bug fix and a new driver for acting as an IPMI device. I was on vacation during the merge window (a long vacation) but this is a bug fix that should go in and a new driver that shouldn't hurt anything. This has been in linux-next for a month or so" * tag 'for-linus-4.9-2' of git://git.code.sf.net/p/openipmi/linux-ipmi: ipmi: fix crash on reading version from proc after unregisted bmc ipmi/bt-bmc: remove redundant return value check of platform_get_resource() ipmi/bt-bmc: add a dependency on ARCH_ASPEED ipmi: Fix ioremap error handling in bt-bmc ipmi: add an Aspeed BT IPMI BMC driver
| * | ipmi: add an Aspeed BT IPMI BMC driverAlistair Popple2016-09-292-0/+19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds a simple device driver to expose the iBT interface on Aspeed SOCs (AST2400 and AST2500) as a character device. Such SOCs are commonly used as BMCs (BaseBoard Management Controllers) and this driver implements the BMC side of the BT interface. The BT (Block Transfer) interface is used to perform in-band IPMI communication between a host and its BMC. Entire messages are buffered before sending a notification to the other end, host or BMC, that there is data to be read. Usually, the host emits requests and the BMC responses but the specification provides a mean for the BMC to send SMS Attention (BMC-to-Host attention or System Management Software attention) messages. For this purpose, the driver introduces a specific ioctl on the device: 'BT_BMC_IOCTL_SMS_ATN' that can be used by the system running on the BMC to signal the host of such an event. The device name defaults to '/dev/ipmi-bt-host' Signed-off-by: Alistair Popple <alistair@popple.id.au> Signed-off-by: Jeremy Kerr <jk@ozlabs.org> Signed-off-by: Joel Stanley <joel@jms.id.au> [clg: - checkpatch fixes - added a devicetree binding documentation - replace 'bt_host' by 'bt_bmc' to reflect that the driver is the BMC side of the IPMI BT interface - renamed the device to 'ipmi-bt-host' - introduced a temporary buffer to copy_{to,from}_user - used platform_get_irq() - moved the driver under drivers/char/ipmi/ but kept it as a misc device - changed the compatible cell to "aspeed,ast2400-bt-bmc" ] Signed-off-by: Cédric Le Goater <clg@kaod.org> Acked-by: Arnd Bergmann <arnd@arndb.de> [clg: - checkpatch --strict fixes - removed the use of devm_iounmap, devm_kfree in cleanup paths - introduced an atomic-t to limit opens to 1 - introduced a mutex to protect write/read operations] Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Cédric Le Goater <clg@kaod.org> Signed-off-by: Corey Minyard <cminyard@mvista.com>
* | | Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds2016-10-221-0/+1
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer updates from Thomas Gleixner: "This updates contains: - A revert which addresses a boot failure on ARM Sun5i platforms - A new clocksource driver, which has been delayed beyond rc1 due to an interrupt driver issue which was unearthed by this driver. The debugging of that issue and the discussion about the proper solution made this driver miss the merge window. There is no point in delaying it for a full cycle as it completes the basic mainline support for the new JCore platform and does not create any risk outside of that platform" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: Revert "clocksource/drivers/timer_sun5i: Replace code by clocksource_mmio_init" clocksource: Add J-Core timer/clocksource driver of: Add J-Core timer bindings
| * | | clocksource: Add J-Core timer/clocksource driverRich Felker2016-10-201-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | At the hardware level, the J-Core PIT is integrated with the interrupt controller, but it is represented as its own device and has an independent programming interface. It provides a 12-bit countdown timer, which is not presently used, and a periodic timer. The interval length for the latter is programmable via a 32-bit throttle register whose units are determined by a bus-period register. The periodic timer is used to implement both periodic and oneshot clock event modes; in oneshot mode the interrupt handler simply disables the timer as soon as it fires. Despite its device tree node representing an interrupt for the PIT, the actual irq generated is programmable, not hard-wired. The driver is responsible for programming the PIT to generate the hardware irq number that the DT assigns to it. On SMP configurations, J-Core provides cpu-local instances of the PIT; no broadcast timer is needed. This driver supports the creation of the necessary per-cpu clock_event_device instances. A nanosecond-resolution clocksource is provided using the J-Core "RTC" registers, which give a 64-bit seconds count and 32-bit nanoseconds that wrap every second. The driver converts these to a full-range 32-bit nanoseconds count. Signed-off-by: Rich Felker <dalias@libc.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: devicetree@vger.kernel.org Cc: linux-sh@vger.kernel.org Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Rob Herring <robh+dt@kernel.org> Link: http://lkml.kernel.org/r/b591ff12cc5ebf63d1edc98da26046f95a233814.1476393790.git.dalias@libc.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | | | Merge branch 'x86-urgent-for-linus' of ↵Linus Torvalds2016-10-221-11/+0
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 fixes from Ingo Molnar: "Three fixes, a hw-enablement and a cross-arch fix/enablement change: - SGI/UV fix for older platforms - x32 signal handling fix - older x86 platform bootup APIC fix - AVX512-4VNNIW (Neural Network Instructions) and AVX512-4FMAPS (Multiply Accumulation Single precision instructions) enablement. - move thread_info back into x86 specific code, to make life easier for other architectures trying to make use of CONFIG_THREAD_INFO_IN_TASK_STRUCT=y" * 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/boot/smp: Don't try to poke disabled/non-existent APIC sched/core, x86: Make struct thread_info arch specific again x86/signal: Remove bogus user_64bit_mode() check from sigaction_compat_abi() x86/platform/UV: Fix support for EFI_OLD_MEMMAP after BIOS callback updates x86/cpufeature: Add AVX512_4VNNIW and AVX512_4FMAPS features x86/vmware: Skip timer_irq_works() check on VMware
| * | | | sched/core, x86: Make struct thread_info arch specific againHeiko Carstens2016-10-201-11/+0
| |/ / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The following commit: c65eacbe290b ("sched/core: Allow putting thread_info into task_struct") ... made 'struct thread_info' a generic struct with only a single ::flags member, if CONFIG_THREAD_INFO_IN_TASK_STRUCT=y is selected. This change however seems to be quite x86 centric, since at least the generic preemption code (asm-generic/preempt.h) assumes that struct thread_info also has a preempt_count member, which apparently was not true for x86. We could add a bit more #ifdefs to solve this problem too, but it seems to be much simpler to make struct thread_info arch specific again. This also makes the conversion to THREAD_INFO_IN_TASK_STRUCT a bit easier for architectures that have a couple of arch specific stuff in their thread_info definition. The arch specific stuff _could_ be moved to thread_struct. However keeping them in thread_info makes it easier: accessing thread_info members is simple, since it is at the beginning of the task_struct, while the thread_struct is at the end. At least on s390 the offsets needed to access members of the thread_struct (with task_struct as base) are too large for various asm instructions. This is not a problem when keeping these members within thread_info. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: keescook@chromium.org Cc: linux-arch@vger.kernel.org Link: http://lkml.kernel.org/r/1476901693-8492-2-git-send-email-mark.rutland@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | | Merge branch 'mm-urgent-for-linus' of ↵Linus Torvalds2016-10-221-1/+1
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull vmap stack fixes from Ingo Molnar: "This is fallout from CONFIG_HAVE_ARCH_VMAP_STACK=y on x86: stack accesses that used to be just somewhat questionable are now totally buggy. These changes try to do it without breaking the ABI: the fields are left there, they are just reporting zero, or reporting narrower information (the maps file change)" * 'mm-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: mm: Change vm_is_stack_for_task() to vm_is_stack_for_current() fs/proc: Stop trying to report thread stacks fs/proc: Stop reporting eip and esp in /proc/PID/stat mm/numa: Remove duplicated include from mprotect.c
| * | | | mm: Change vm_is_stack_for_task() to vm_is_stack_for_current()Andy Lutomirski2016-10-201-1/+1
| |/ / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Asking for a non-current task's stack can't be done without races unless the task is frozen in kernel mode. As far as I know, vm_is_stack_for_task() never had a safe non-current use case. The __unused annotation is because some KSTK_ESP implementations ignore their parameter, which IMO is further justification for this patch. Signed-off-by: Andy Lutomirski <luto@kernel.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Jann Horn <jann@thejh.net> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Linux API <linux-api@vger.kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tycho Andersen <tycho.andersen@canonical.com> Link: http://lkml.kernel.org/r/4c3f68f426e6c061ca98b4fc7ef85ffbb0a25b0c.1475257877.git.luto@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* | | | Merge branch 'irq-urgent-for-linus' of ↵Linus Torvalds2016-10-221-1/+1
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq fixes from Ingo Molnar: "Mostly irqchip driver fixes, plus a symbol export" * 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: kernel/irq: Export irq_set_parent() irqchip/gic: Add missing \n to CPU IF adjustment message irqchip/jcore: Don't show Kconfig menu item for driver irqchip/eznps: Drop pointless static qualifier in nps400_of_init() irqchip/gic-v3-its: Fix entry size mask for GITS_BASER irqchip/gic-v3-its: Fix 64bit GIC{R,ITS}_TYPER accesses
| * \ \ \ Merge tag 'gic-fixes-for-4.9-rc2' of ↵Thomas Gleixner2016-10-211-1/+1
| |\ \ \ \ | | |/ / / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/urgent Pull GIC updates from Marc Zyngier: - Fix for 32bit accesses that should be 64bit on 64bit machines - Fix for a field decoding macro - Beautify a warning message
| | * | | irqchip/gic-v3-its: Fix entry size mask for GITS_BASERVladimir Murzin2016-10-171-1/+1
| | | |/ | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Entry Size in GITS_BASER<n> occupies 5 bits [52:48], but we mask out 8 bits. Fixes: cc2d3216f53c ("irqchip: GICv3: ITS command queue") Cc: stable@vger.kernel.org Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
* | | | Merge tag 'acpi-4.9-rc2' of ↵Linus Torvalds2016-10-211-1/+1
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI fixes from Rafael Wysocki: "These fix an issue related to system resume in the new WDAT-based watchdog driver and a return value of a stub function in the ACPI CPPC framework. Specifics: - Update the ACPI WDAT-based watchdog driver to ping the hardware during system resume to prevent a reset from occurring after the resume is complete (Mika Westerberg). - Fix the return value of the pcc_mbox_request_channel() stub for CONFIG_PCC unset (Hoan Tran)" * tag 'acpi-4.9-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: watchdog: wdat_wdt: Ping the watchdog on resume mailbox: PCC: Fix return value of pcc_mbox_request_channel()
| | \ \ \
| | \ \ \
| *-. \ \ \ Merge branches 'acpi-wdat' and 'acpi-cppc'Rafael J. Wysocki2016-10-211-1/+1
| |\ \ \ \ \ | | |_|_|/ / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * acpi-wdat: watchdog: wdat_wdt: Ping the watchdog on resume * acpi-cppc: mailbox: PCC: Fix return value of pcc_mbox_request_channel()
| | | * | | mailbox: PCC: Fix return value of pcc_mbox_request_channel()Hoan Tran2016-10-171-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When CONFIG_PCC is disabled, pcc_mbox_request_channel() needs to return ERR_PTR(-ENODEV), not a NULL pointer, as the callers of this function use IS_ERR() to check for error code. Signed-off-by: Duc Dang <dhdang@apm.com> Signed-off-by: Hoan Tran <hotran@apm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* | | | | | Merge branch 'for-linus' of git://git.kernel.dk/linux-blockLinus Torvalds2016-10-211-9/+40
|\ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull block fixes from Jens Axboe: "A set of fixes that missed the merge window, mostly due to me being away around that time. Nothing major here, a mix of nvme cleanups and fixes, and one fix for the badblocks handling" * 'for-linus' of git://git.kernel.dk/linux-block: nvmet: use symbolic constants for CNS values nvme: use symbolic constants for CNS values nvme.h: add an enum for cns values nvme.h: don't use uuid_be nvme.h: resync with nvme-cli nvme: Add tertiary number to NVME_VS nvme : Add sysfs entry for NVMe CMBs when appropriate nvme: don't schedule multiple resets nvme: Delete created IO queues on reset nvme: Stop probing a removed device badblocks: fix overlapping check for clearing
| * | | | | | nvme.h: add an enum for cns valuesChristoph Hellwig2016-10-191-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Ported over from nvme-cli. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Gabriel Krisman Bertazi <krisman@linux.vnet.ibm.com> Reviewed-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
| * | | | | | nvme.h: don't use uuid_beChristoph Hellwig2016-10-191-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This makes life easier for nvme-cli and we don't really need the uuid type anyway to start with. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Gabriel Krisman Bertazi <krisman@linux.vnet.ibm.com> Reviewed-by: Jay Freyensee <james_p_freyensee@linux.intel.com> Signed-off-by: Jens Axboe <axboe@fb.com>
| * | | | | | nvme.h: resync with nvme-cliChristoph Hellwig2016-10-191-6/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Import a few updates to nvme.h from nvme-cli. This mostly includes a few new fields and error codes, but also a few renames that so far are only used in user space. Also one field is moved from an array of two le64 values to one of 16 u8 values so that we can more easily access it. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Keith Busch <keith.busch@intel.com> Reviewed-by: Gabriel Krisman Bertazi <krisman@linux.vnet.ibm.com> Signed-off-by: Jens Axboe <axboe@fb.com>
| * | | | | | nvme: Add tertiary number to NVME_VSGabriel Krisman Bertazi2016-10-191-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | NVMe 1.2.1 specification adds a tertiary element to the version number. This updates the macro and its callers to include the final number and fixup a single place in nvmet where the version was generated manually. Signed-off-by: Gabriel Krisman Bertazi <krisman@linux.vnet.ibm.com> Reviewed-by: Sagi Grimberg <sagi@grimberg.me> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <axboe@fb.com>
* | | | | | | Merge tag 'pm-4.9-rc2' of ↵Linus Torvalds2016-10-201-2/+2
|\ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management fix from Rafael Wysocki: "This fixes the pointer arithmetics mess-up in the cpufreq core introduced by one of recent commits and leading to all kinds of breakage from kernel crashes to incorrect governor decisions (Sergey Senozhatsky)" * tag 'pm-4.9-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: cpufreq: fix overflow in cpufreq_table_find_index_dl()
| * \ \ \ \ \ \ Merge branch 'pm-cpufreq'Rafael J. Wysocki2016-10-201-2/+2
| |\ \ \ \ \ \ \ | | |_|/ / / / / | |/| | | | | | | | | | | | | | | | | | | | | | * pm-cpufreq: cpufreq: fix overflow in cpufreq_table_find_index_dl()
| | * | | | | | cpufreq: fix overflow in cpufreq_table_find_index_dl()Sergey Senozhatsky2016-10-201-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 'best' is always less or equals to 'pos', so `best - pos' returns a negative value which is then getting casted to `unsigned int' and passed to __cpufreq_driver_target()->acpi_cpufreq_target() for policy->freq_table selection. This results in BUG: unable to handle kernel paging request at ffff881019b469f8 IP: [<ffffffffa00356c1>] acpi_cpufreq_target+0x4f/0x190 [acpi_cpufreq] PGD 267f067 PUD 0 Oops: 0000 [#1] PREEMPT SMP CPU: 6 PID: 70 Comm: kworker/6:1 Not tainted 4.9.0-rc1-next-20161017-dbg-dirty Workqueue: events dbs_work_handler task: ffff88041b808000 task.stack: ffff88041b810000 RIP: 0010:[<ffffffffa00356c1>] [<ffffffffa00356c1>] acpi_cpufreq_target+0x4f/0x190 [acpi_cpufreq] RSP: 0018:ffff88041b813c60 EFLAGS: 00010282 RAX: ffff880419b46a00 RBX: ffff88041b848400 RCX: ffff880419b20f80 RDX: 00000000001dff38 RSI: 00000000ffffffff RDI: ffff88041b848400 RBP: ffff88041b813cb0 R08: 0000000000000006 R09: 0000000000000040 R10: ffffffff8207f9e0 R11: ffffffff8173595b R12: 0000000000000000 R13: ffff88041f1dff38 R14: 0000000000262900 R15: 0000000bfffffff4 FS: 0000000000000000(0000) GS:ffff88041f000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffff881019b469f8 CR3: 000000041a2d3000 CR4: 00000000001406e0 Stack: ffff88041b813cb0 ffffffff813347f9 ffff88041b813ca0 ffffffff81334663 ffff88041f1d4bc0 ffff88041b848400 0000000000000000 0000000000000000 0000000000262900 0000000000000000 ffff88041b813d00 ffffffff813355dc Call Trace: [<ffffffff813347f9>] ? cpufreq_freq_transition_begin+0xf1/0xfc [<ffffffff81334663>] ? get_cpu_idle_time+0x97/0xa6 [<ffffffff813355dc>] __cpufreq_driver_target+0x3b6/0x44e [<ffffffff81336ca3>] cs_dbs_timer+0x11a/0x135 [<ffffffff81336fda>] dbs_work_handler+0x39/0x62 [<ffffffff81057823>] process_one_work+0x280/0x4a5 [<ffffffff81058719>] worker_thread+0x24f/0x397 [<ffffffff810584ca>] ? rescuer_thread+0x30b/0x30b [<ffffffff81418380>] ? nl80211_get_key+0x29/0x36a [<ffffffff8105d2b7>] kthread+0xfc/0x104 [<ffffffff8107ceea>] ? put_lock_stats.isra.9+0xe/0x20 [<ffffffff8105d1bb>] ? kthread_create_on_node+0x3f/0x3f [<ffffffff814b2092>] ret_from_fork+0x22/0x30 Code: 56 4d 6b ff 0c 41 55 41 54 53 48 83 ec 28 48 8b 15 ad 1e 00 00 44 8b 41 08 48 8b 87 c8 00 00 00 49 89 d5 4e 03 2c c5 80 b2 78 81 <46> 8b 74 38 04 45 3b 75 00 75 11 31 c0 83 39 00 0f 84 1c 01 00 RIP [<ffffffffa00356c1>] acpi_cpufreq_target+0x4f/0x190 [acpi_cpufreq] RSP <ffff88041b813c60> CR2: ffff881019b469f8 ---[ end trace 16d9fc7a17897d37 ]--- [ rjw: In some cases this bug may also cause incorrect frequencies to be selected by cpufreq governors. ] Fixes: 899bb6642f2a (cpufreq: skip invalid entries when searching the frequency) Link: http://marc.info/?l=linux-kernel&m=147672030714331&w=2 Reported-and-tested-by: Sedat Dilek <sedat.dilek@gmail.com> Reported-and-tested-by: Jörg Otte <jrg.otte@gmail.com> Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Cc: 4.8+ <stable@vger.kernel.org> # 4.8+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
* | | | | | | | Merge branch 'gup_flag-cleanups'Linus Torvalds2016-10-191-9/+10
|\ \ \ \ \ \ \ \ | |_|_|_|_|_|/ / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 38e088546522 ("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()
| * | | | | | | mm: replace access_process_vm() write parameter with gup_flagsLorenzo Stoakes2016-10-191-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | | | | | | mm: replace access_remote_vm() write parameter with gup_flagsLorenzo Stoakes2016-10-191-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | | | | | | mm: replace get_user_pages_remote() write/force parameters with gup_flagsLorenzo Stoakes2016-10-191-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | | | | | | mm: replace get_user_pages() write/force parameters with gup_flagsLorenzo Stoakes2016-10-191-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | | | | | | mm: replace get_vaddr_frames() write/force parameters with gup_flagsLorenzo Stoakes2016-10-191-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | | | | | | mm: replace get_user_pages_locked() write/force parameters with gup_flagsLorenzo Stoakes2016-10-191-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | | | | | | mm: replace get_user_pages_unlocked() write/force parameters with gup_flagsLorenzo Stoakes2016-10-181-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | | | | | | mm: remove write/force parameters from __get_user_pages_unlocked()Lorenzo Stoakes2016-10-181-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | | | | | | mm: remove gup_flags FOLL_WRITE games from __get_user_pages()Linus Torvalds2016-10-181-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is an ancient bug that was actually attempted to be fixed once (badly) by me eleven years ago in commit 4ceb5db9757a ("Fix get_user_pages() race for write access") but that was then undone due to problems on s390 by commit f33ea7f404e5 ("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 abf09bed3cce ("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>
* | | | | | | | Merge branch 'perf-urgent-for-linus' of ↵Linus Torvalds2016-10-181-0/+2
|\ \ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull perf fixes from Ingo Molnar: "Four tooling fixes, two kprobes KASAN related fixes and an x86 PMU driver fix/cleanup" * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: perf jit: Fix build issue on Ubuntu perf jevents: Handle events including .c and .o perf/x86/intel: Remove an inconsistent NULL check kprobes: Unpoison stack in jprobe_return() for KASAN kprobes: Avoid false KASAN reports during stack copy perf header: Set nr_numa_nodes only when we parsed all the data perf top: Fix refreshing hierarchy entries on TUI
| * | | | | | | | kprobes: Unpoison stack in jprobe_return() for KASANDmitry Vyukov2016-10-161-0/+2
| | |/ / / / / / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I observed false KSAN positives in the sctp code, when sctp uses jprobe_return() in jsctp_sf_eat_sack(). The stray 0xf4 in shadow memory are stack redzones: [ ] ================================================================== [ ] BUG: KASAN: stack-out-of-bounds in memcmp+0xe9/0x150 at addr ffff88005e48f480 [ ] Read of size 1 by task syz-executor/18535 [ ] page:ffffea00017923c0 count:0 mapcount:0 mapping: (null) index:0x0 [ ] flags: 0x1fffc0000000000() [ ] page dumped because: kasan: bad access detected [ ] CPU: 1 PID: 18535 Comm: syz-executor Not tainted 4.8.0+ #28 [ ] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ ] ffff88005e48f2d0 ffffffff82d2b849 ffffffff0bc91e90 fffffbfff10971e8 [ ] ffffed000bc91e90 ffffed000bc91e90 0000000000000001 0000000000000000 [ ] ffff88005e48f480 ffff88005e48f350 ffffffff817d3169 ffff88005e48f370 [ ] Call Trace: [ ] [<ffffffff82d2b849>] dump_stack+0x12e/0x185 [ ] [<ffffffff817d3169>] kasan_report+0x489/0x4b0 [ ] [<ffffffff817d31a9>] __asan_report_load1_noabort+0x19/0x20 [ ] [<ffffffff82d49529>] memcmp+0xe9/0x150 [ ] [<ffffffff82df7486>] depot_save_stack+0x176/0x5c0 [ ] [<ffffffff817d2031>] save_stack+0xb1/0xd0 [ ] [<ffffffff817d27f2>] kasan_slab_free+0x72/0xc0 [ ] [<ffffffff817d05b8>] kfree+0xc8/0x2a0 [ ] [<ffffffff85b03f19>] skb_free_head+0x79/0xb0 [ ] [<ffffffff85b0900a>] skb_release_data+0x37a/0x420 [ ] [<ffffffff85b090ff>] skb_release_all+0x4f/0x60 [ ] [<ffffffff85b11348>] consume_skb+0x138/0x370 [ ] [<ffffffff8676ad7b>] sctp_chunk_put+0xcb/0x180 [ ] [<ffffffff8676ae88>] sctp_chunk_free+0x58/0x70 [ ] [<ffffffff8677fa5f>] sctp_inq_pop+0x68f/0xef0 [ ] [<ffffffff8675ee36>] sctp_assoc_bh_rcv+0xd6/0x4b0 [ ] [<ffffffff8677f2c1>] sctp_inq_push+0x131/0x190 [ ] [<ffffffff867bad69>] sctp_backlog_rcv+0xe9/0xa20 [ ... ] [ ] Memory state around the buggy address: [ ] ffff88005e48f380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ ] ffff88005e48f400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ ] >ffff88005e48f480: f4 f4 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ ] ^ [ ] ffff88005e48f500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ ] ffff88005e48f580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ ] ================================================================== KASAN stack instrumentation poisons stack redzones on function entry and unpoisons them on function exit. If a function exits abnormally (e.g. with a longjmp like jprobe_return()), stack redzones are left poisoned. Later this leads to random KASAN false reports. Unpoison stack redzones in the frames we are going to jump over before doing actual longjmp in jprobe_return(). Signed-off-by: Dmitry Vyukov <dvyukov@google.com> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Reviewed-by: Mark Rutland <mark.rutland@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Cc: Alexander Potapenko <glider@google.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: kasan-dev@googlegroups.com Cc: surovegin@google.com Cc: rostedt@goodmis.org Link: http://lkml.kernel.org/r/1476454043-101898-1-git-send-email-dvyukov@google.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* / | | | | | | generic syscalls: kill cruft from removed pkey syscallsDave Hansen2016-10-172-7/+0
|/ / / / / / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | pkey_set() and pkey_get() were syscalls present in older versions of the protection keys patches. They were fully excised from the x86 code, but some cruft was left in the generic syscall code. The C++ comments were intended to help to make it more glaring to me to fix them before actually submitting them. That technique worked, but later than I would have liked. I test-compiled this for arm64. Fixes: a60f7b69d92c0 ("generic syscalls: Wire up memory protection keys syscalls") Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: x86@kernel.org Cc: linux-arch@vger.kernel.org Cc: mgorman@techsingularity.net Cc: linux-api@vger.kernel.org Cc: linux-mm@kvack.org Cc: luto@kernel.org Cc: akpm@linux-foundation.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | | | | | Merge tag 'gcc-plugins-v4.9-rc1' of ↵Linus Torvalds2016-10-156-6/+29
|\ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull gcc plugins update from Kees Cook: "This adds a new gcc plugin named "latent_entropy". It is designed to extract as much possible uncertainty from a running system at boot time as possible, hoping to capitalize on any possible variation in CPU operation (due to runtime data differences, hardware differences, SMP ordering, thermal timing variation, cache behavior, etc). At the very least, this plugin is a much more comprehensive example for how to manipulate kernel code using the gcc plugin internals" * tag 'gcc-plugins-v4.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: latent_entropy: Mark functions with __latent_entropy gcc-plugins: Add latent_entropy plugin
| * | | | | | | latent_entropy: Mark functions with __latent_entropyEmese Revfy2016-10-106-6/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The __latent_entropy gcc attribute can be used only on functions and variables. If it is on a function then the plugin will instrument it for gathering control-flow entropy. If the attribute is on a variable then the plugin will initialize it with random contents. The variable must be an integer, an integer array type or a structure with integer fields. These specific functions have been selected because they are init functions (to help gather boot-time entropy), are called at unpredictable times, or they have variable loops, each of which provide some level of latent entropy. Signed-off-by: Emese Revfy <re.emese@gmail.com> [kees: expanded commit message] Signed-off-by: Kees Cook <keescook@chromium.org>
| * | | | | | | gcc-plugins: Add latent_entropy pluginEmese Revfy2016-10-101-0/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This adds a new gcc plugin named "latent_entropy". It is designed to extract as much possible uncertainty from a running system at boot time as possible, hoping to capitalize on any possible variation in CPU operation (due to runtime data differences, hardware differences, SMP ordering, thermal timing variation, cache behavior, etc). At the very least, this plugin is a much more comprehensive example for how to manipulate kernel code using the gcc plugin internals. The need for very-early boot entropy tends to be very architecture or system design specific, so this plugin is more suited for those sorts of special cases. The existing kernel RNG already attempts to extract entropy from reliable runtime variation, but this plugin takes the idea to a logical extreme by permuting a global variable based on any variation in code execution (e.g. a different value (and permutation function) is used to permute the global based on loop count, case statement, if/then/else branching, etc). To do this, the plugin starts by inserting a local variable in every marked function. The plugin then adds logic so that the value of this variable is modified by randomly chosen operations (add, xor and rol) and random values (gcc generates separate static values for each location at compile time and also injects the stack pointer at runtime). The resulting value depends on the control flow path (e.g., loops and branches taken). Before the function returns, the plugin mixes this local variable into the latent_entropy global variable. The value of this global variable is added to the kernel entropy pool in do_one_initcall() and _do_fork(), though it does not credit any bytes of entropy to the pool; the contents of the global are just used to mix the pool. Additionally, the plugin can pre-initialize arrays with build-time random contents, so that two different kernel builds running on identical hardware will not have the same starting values. Signed-off-by: Emese Revfy <re.emese@gmail.com> [kees: expanded commit message and code comments] Signed-off-by: Kees Cook <keescook@chromium.org>