aboutsummaryrefslogtreecommitdiffstats
Commit message (Collapse)AuthorAge
* Merge tag 'driver-core-3.15-rc1' of ↵Linus Torvalds2014-04-01
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core and sysfs updates from Greg KH: "Here's the big driver core / sysfs update for 3.15-rc1. Lots of kernfs updates to make it useful for other subsystems, and a few other tiny driver core patches. All have been in linux-next for a while" * tag 'driver-core-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (42 commits) Revert "sysfs, driver-core: remove unused {sysfs|device}_schedule_callback_owner()" kernfs: cache atomic_write_len in kernfs_open_file numa: fix NULL pointer access and memory leak in unregister_one_node() Revert "driver core: synchronize device shutdown" kernfs: fix off by one error. kernfs: remove duplicate dir.c at the top dir x86: align x86 arch with generic CPU modalias handling cpu: add generic support for CPU feature based module autoloading sysfs: create bin_attributes under the requested group driver core: unexport static function create_syslog_header firmware: use power efficient workqueue for unloading and aborting fw load firmware: give a protection when map page failed firmware: google memconsole driver fixes firmware: fix google/gsmi duplicate efivars_sysfs_init() drivers/base: delete non-required instances of include <linux/init.h> kernfs: fix kernfs_node_from_dentry() ACPI / platform: drop redundant ACPI_HANDLE check kernfs: fix hash calculation in kernfs_rename_ns() kernfs: add CONFIG_KERNFS sysfs, kobject: add sysfs wrapper for kernfs_enable_ns() ...
| * Revert "sysfs, driver-core: remove unused ↵Greg Kroah-Hartman2014-03-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | {sysfs|device}_schedule_callback_owner()" This reverts commit d1ba277e79889085a2faec3b68b91ce89c63f888. As reported by Stephen, this patch breaks linux-next as a ppc patch suddenly (after 2 years) started using this old api call. So revert it for now, it will go away in 3.15-rc2 when we can change the PPC call to the new api. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Tejun Heo <tj@kernel.org> Cc: Stewart Smith <stewart@linux.vnet.ibm.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * kernfs: cache atomic_write_len in kernfs_open_fileTejun Heo2014-03-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While implementing atomic_write_len, 4d3773c4bb41 ("kernfs: implement kernfs_ops->atomic_write_len") moved data copy from userland inside kernfs_get_active() and kernfs_open_file->mutex so that kernfs_ops->atomic_write_len can be accessed before copying buffer from userland; unfortunately, this could lead to locking order inversion involving mmap_sem if copy_from_user() takes a page fault. ====================================================== [ INFO: possible circular locking dependency detected ] 3.14.0-rc4-next-20140228-sasha-00011-g4077c67-dirty #26 Tainted: G W ------------------------------------------------------- trinity-c236/10658 is trying to acquire lock: (&of->mutex#2){+.+.+.}, at: [<fs/kernfs/file.c:487>] kernfs_fop_mmap+0x54/0x120 but task is already holding lock: (&mm->mmap_sem){++++++}, at: [<mm/util.c:397>] vm_mmap_pgoff+0x6e/0xe0 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&mm->mmap_sem){++++++}: [<kernel/locking/lockdep.c:1945 kernel/locking/lockdep.c:2131>] validate_chain+0x6c5/0x7b0 [<kernel/locking/lockdep.c:3182>] __lock_acquire+0x4cd/0x5a0 [<arch/x86/include/asm/current.h:14 kernel/locking/lockdep.c:3602>] lock_acquire+0x182/0x1d0 [<mm/memory.c:4188>] might_fault+0x7e/0xb0 [<arch/x86/include/asm/uaccess.h:713 fs/kernfs/file.c:291>] kernfs_fop_write+0xd8/0x190 [<fs/read_write.c:473>] vfs_write+0xe3/0x1d0 [<fs/read_write.c:523 fs/read_write.c:515>] SyS_write+0x5d/0xa0 [<arch/x86/kernel/entry_64.S:749>] tracesys+0xdd/0xe2 -> #0 (&of->mutex#2){+.+.+.}: [<kernel/locking/lockdep.c:1840>] check_prev_add+0x13f/0x560 [<kernel/locking/lockdep.c:1945 kernel/locking/lockdep.c:2131>] validate_chain+0x6c5/0x7b0 [<kernel/locking/lockdep.c:3182>] __lock_acquire+0x4cd/0x5a0 [<arch/x86/include/asm/current.h:14 kernel/locking/lockdep.c:3602>] lock_acquire+0x182/0x1d0 [<kernel/locking/mutex.c:470 kernel/locking/mutex.c:571>] mutex_lock_nested+0x6a/0x510 [<fs/kernfs/file.c:487>] kernfs_fop_mmap+0x54/0x120 [<mm/mmap.c:1573>] mmap_region+0x310/0x5c0 [<mm/mmap.c:1365>] do_mmap_pgoff+0x385/0x430 [<mm/util.c:399>] vm_mmap_pgoff+0x8f/0xe0 [<mm/mmap.c:1416 mm/mmap.c:1374>] SyS_mmap_pgoff+0x1b0/0x210 [<arch/x86/kernel/sys_x86_64.c:72>] SyS_mmap+0x1d/0x20 [<arch/x86/kernel/entry_64.S:749>] tracesys+0xdd/0xe2 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&mm->mmap_sem); lock(&of->mutex#2); lock(&mm->mmap_sem); lock(&of->mutex#2); *** DEADLOCK *** 1 lock held by trinity-c236/10658: #0: (&mm->mmap_sem){++++++}, at: [<mm/util.c:397>] vm_mmap_pgoff+0x6e/0xe0 stack backtrace: CPU: 2 PID: 10658 Comm: trinity-c236 Tainted: G W 3.14.0-rc4-next-20140228-sasha-00011-g4077c67-dirty #26 0000000000000000 ffff88011911fa48 ffffffff8438e945 0000000000000000 0000000000000000 ffff88011911fa98 ffffffff811a0109 ffff88011911fab8 ffff88011911fab8 ffff88011911fa98 ffff880119128cc0 ffff880119128cf8 Call Trace: [<lib/dump_stack.c:52>] dump_stack+0x52/0x7f [<kernel/locking/lockdep.c:1213>] print_circular_bug+0x129/0x160 [<kernel/locking/lockdep.c:1840>] check_prev_add+0x13f/0x560 [<include/linux/spinlock.h:343 mm/slub.c:1933>] ? deactivate_slab+0x511/0x550 [<kernel/locking/lockdep.c:1945 kernel/locking/lockdep.c:2131>] validate_chain+0x6c5/0x7b0 [<kernel/locking/lockdep.c:3182>] __lock_acquire+0x4cd/0x5a0 [<mm/mmap.c:1552>] ? mmap_region+0x24a/0x5c0 [<arch/x86/include/asm/current.h:14 kernel/locking/lockdep.c:3602>] lock_acquire+0x182/0x1d0 [<fs/kernfs/file.c:487>] ? kernfs_fop_mmap+0x54/0x120 [<kernel/locking/mutex.c:470 kernel/locking/mutex.c:571>] mutex_lock_nested+0x6a/0x510 [<fs/kernfs/file.c:487>] ? kernfs_fop_mmap+0x54/0x120 [<kernel/sched/core.c:2477>] ? get_parent_ip+0x11/0x50 [<fs/kernfs/file.c:487>] ? kernfs_fop_mmap+0x54/0x120 [<fs/kernfs/file.c:487>] kernfs_fop_mmap+0x54/0x120 [<mm/mmap.c:1573>] mmap_region+0x310/0x5c0 [<mm/mmap.c:1365>] do_mmap_pgoff+0x385/0x430 [<mm/util.c:397>] ? vm_mmap_pgoff+0x6e/0xe0 [<mm/util.c:399>] vm_mmap_pgoff+0x8f/0xe0 [<kernel/rcu/update.c:97>] ? __rcu_read_unlock+0x44/0xb0 [<fs/file.c:641>] ? dup_fd+0x3c0/0x3c0 [<mm/mmap.c:1416 mm/mmap.c:1374>] SyS_mmap_pgoff+0x1b0/0x210 [<arch/x86/kernel/sys_x86_64.c:72>] SyS_mmap+0x1d/0x20 [<arch/x86/kernel/entry_64.S:749>] tracesys+0xdd/0xe2 Fix it by caching atomic_write_len in kernfs_open_file during open so that it can be determined without accessing kernfs_ops in kernfs_fop_write(). This restores the structure of kernfs_fop_write() before 4d3773c4bb41 with updated @len determination logic. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Sasha Levin <sasha.levin@oracle.com> References: http://lkml.kernel.org/g/53113485.2090407@oracle.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * numa: fix NULL pointer access and memory leak in unregister_one_node()Xishi Qiu2014-03-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When doing socket hot remove, "node_devices[nid]" is set to NULL; acpi_processor_remove() try_offline_node() unregister_one_node() Then hot add a socket, but do not echo 1 > /sys/devices/system/cpu/cpuXX/online, so register_one_node() will not be called, and "node_devices[nid]" is still NULL. If doing socket hot remove again, NULL pointer access will be happen. unregister_one_node() unregister_node() Another, we should free the memory used by "node_devices[nid]" in unregister_one_node(). Signed-off-by: Xishi Qiu <qiuxishi@huawei.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * Revert "driver core: synchronize device shutdown"Roland Dreier2014-03-09
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This reverts commit 401097ea4b89846d66ac78f7f108d49c2e922d9c. The original changelog said: A patch series to make .shutdown execute asynchronously. Some drivers's shutdown can take a lot of time. The patches can help save some shutdown time. The patches use Arjan's async API. This patch: synchronize all tasks submitted by .shutdown However, I'm not able to find any evidence that any other patches from this series were applied, nor am I able to find any async tasks that are scheduled in a .shutdown context. On the other hand, we see occasional hangs on shutdown that appear to be caused by the async_synchronize_full() in device_shutdown() waiting forever for the async probing in sd if a SCSI disk shows up at just the wrong time — the system starts the probe, but begins shutting down and tears down too much of the SCSI driver to finish the probe. If we had any async shutdown tasks, I guess the right fix would be to create a "shutdown" async domain and have device_shutdown() only wait for that domain. But since there apparently are no async shutdown tasks, we can just revert the waiting. Signed-off-by: Roland Dreier <roland@purestorage.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * kernfs: fix off by one error.Richard Cochran2014-03-09
| | | | | | | | | | | | | | | | | | | | | | The hash values 0 and 1 are reserved for magic directory entries, but the code only prevents names hashing to 0. This patch fixes the test to also prevent hash value 1. Signed-off-by: Richard Cochran <richardcochran@gmail.com> Cc: <stable@vger.kernel.org> Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * Merge 3.14-rc5 into driver-core-nextGreg Kroah-Hartman2014-03-02
| |\ | | | | | | | | | We want the fixes in here.
| * | kernfs: remove duplicate dir.c at the top dirTejun Heo2014-02-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | a8fa94e0f2ab ("Merge branch 'master' into driver-core-next-test-merge-rc2") mistakenly introduced a duplicate dir.c at the top directory. Remove it. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | x86: align x86 arch with generic CPU modalias handlingArd Biesheuvel2014-02-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The x86 CPU feature modalias handling existed before it was reimplemented generically. This patch aligns the x86 handling so that it (a) reuses some more code that is now generic; (b) uses the generic format for the modalias module metadata entry, i.e., it now uses 'cpu:type:x86,venVVVVfamFFFFmodMMMM:feature:,XXXX,YYYY' instead of the 'x86cpu:vendor:VVVV:family:FFFF:model:MMMM:feature:,XXXX,YYYY' that was used before. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: H. Peter Anvin <hpa@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | cpu: add generic support for CPU feature based module autoloadingArd Biesheuvel2014-02-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds support for advertising optional CPU features over udev using the modalias, and for declaring compatibility with/dependency upon such a feature in a module. The mapping between feature numbers and actual features should be provided by the architecture in a file called <asm/cpufeature.h> which exports the following functions/macros: - cpu_feature(FEAT), a preprocessor macro that maps token FEAT to a numeric index; - bool cpu_have_feature(n), returning whether this CPU has support for feature #n; - MAX_CPU_FEATURES, an upper bound for 'n' in the previous function. The feature can then be enabled by setting CONFIG_GENERIC_CPU_AUTOPROBE for the architecture. For instance, a module that registers its module init function using module_cpu_feature_match(FEAT_X, module_init_function) will be probed automatically when the CPU's support for the 'FEAT_X' feature is advertised over udev, and will only allow the module to be loaded by hand if the 'FEAT_X' feature is supported. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | Merge 3.14-rc3 into driver-core-nextGreg Kroah-Hartman2014-02-18
| |\ \ | | | | | | | | | | | | | | | | | | | | We want those fixes here for testing and development. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | sysfs: create bin_attributes under the requested groupCody P Schafer2014-02-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | bin_attributes created/updated in create_files() (such as those listed via (struct device).attribute_groups) were not placed under the specified group, and instead appeared in the base kobj directory. Fix this by making bin_attributes use creating code similar to normal attributes. A quick grep shows that no one is using bin_attrs in a named attribute group yet, so we can do this without breaking anything in usespace. Note that I do not add is_visible() support to bin_attributes, though that could be done as well. Signed-off-by: Cody P Schafer <cody@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | driver core: unexport static function create_syslog_headerJiang Liu2014-02-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Function create_syslog_header() is defined as static, so it should not be exported. Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | firmware: use power efficient workqueue for unloading and aborting fw loadShaibal Dutta2014-02-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Allow the scheduler to select the most appropriate CPU for running the firmware load timeout routine and delayed routine for firmware unload. This extends idle residency times and conserves power. This functionality is enabled when CONFIG_WQ_POWER_EFFICIENT is selected. Cc: Ming Lei <ming.lei@canonical.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Shaibal Dutta <shaibal.dutta@broadcom.com> [zoran.markovic@linaro.org: Rebased to latest kernel, added commit message. Fixed code alignment.] Signed-off-by: Zoran Markovic <zoran.markovic@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | firmware: give a protection when map page failedzhang jun2014-02-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | so, we need give a protection and return a error value. [ 7341.474236] [drm:do_intel_finish_page_flip] *ERROR* invalid or inactive unpin_work! [ 7341.494464] atomisp-css2400b0_v21 0000:00:03.0: unhandled css stored event: 0x20 [ 7341.503627] vmap allocation for size 208896 failed: use vmalloc=<size> to increase size.<=================== map failed [ 7341.507135] [drm:do_intel_finish_page_flip] *ERROR* invalid or inactive unpin_work! [ 7341.503848] BUG: unable to handle kernel NULL pointer dereference at (null) [ 7341.520394] IP: [<c18f5c1b>] sst_load_all_modules_elf+0x1bb/0x850 [ 7341.527216] *pdpt = 0000000030dfe001 *pde = 0000000000000000 [ 7341.533640] Oops: 0000 [#1] PREEMPT SMP [ 7341.540360] [drm:do_intel_finish_page_flip] *ERROR* invalid or inactive unpin_work! [ 7341.538037] Modules linked in: atomisp_css2400b0_v21 lm3554 ov2722 imx1x5 atmel_mxt_ts vxd392 videobuf_vmalloc videobuf_core lm_dump(O) bcm_bt_lpm hdmi_audio bcm4334x(O) [ 7341.563531] CPU: 1 PID: 525 Comm: mediaserver Tainted: G W O 3.10.20-262518-ga83c053 #1 [ 7341.573253] task: f0994ec0 ti: f09f0000 task.ti: f09f0000 [ 7341.579284] EIP: 0060:[<c18f5c1b>] EFLAGS: 00010246 CPU: 1 [ 7341.585415] EIP is at sst_load_all_modules_elf+0x1bb/0x850 [ 7341.591541] EAX: 00000000 EBX: e3595ba0 ECX: 00000000 EDX: 00031c1c [ 7341.598541] ESI: e04a0000 EDI: 00000000 EBP: f09f1d80 ESP: f09f1cf4 [ 7341.605542] DS: 007b ES: 007b FS: 00d8 GS: 003b SS: 0068 [ 7341.611573] CR0: 80050033 CR2: 00000000 CR3: 30db4000 CR4: 001007f0 [ 7341.618573] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000 [ 7341.625575] DR6: ffff0ff0 DR7: 00000400 [ 7341.629856] Stack: [ 7341.632097] f09f1d57 00000019 c1d656d7 c1d658d3 c1d56409 00000f28 c1d64af9 18000103 [ 7341.640766] 01000001 00080000 c1f910a0 f326f4c8 00000034 f326f520 00000002 e04a02bc [ 7341.649465] 00000001 f326e014 c1f910b0 e04a0000 c0080100 00031c1c e3595ba0 c0080100 [ 7341.658149] Call Trace: [ 7341.660888] [<c18f6308>] sst_post_download_byt+0x58/0xb0 [ 7341.666925] [<c18f4fbc>] sst_load_fw+0xdc/0x510 [ 7341.672086] [<c1a7b2c0>] ? __mutex_lock_slowpath+0x250/0x370 [ 7341.678507] [<c1a80e05>] ? sub_preempt_count+0x55/0xe0 [ 7341.684346] [<c18f1294>] sst_download_fw+0x14/0x60 [ 7341.689796] [<c1a7b403>] ? mutex_lock+0x23/0x30 [ 7341.694954] [<c18f191c>] intel_sst_check_device+0x6c/0x120 [ 7341.701181] [<c18f1d08>] sst_set_generic_params+0x1b8/0x4a0 [ 7341.707504] [<c1a80e05>] ? sub_preempt_count+0x55/0xe0 [ 7341.713341] [<c1a80e05>] ? sub_preempt_count+0x55/0xe0 [ 7341.719178] [<c1a7b2c0>] ? __mutex_lock_slowpath+0x250/0x370 [ 7341.725600] [<c1320d84>] ? __kmalloc_track_caller+0xe4/0x1d0 [ 7341.732022] [<c18e35f5>] sst_set_mixer_param+0x25/0x40 [ 7341.737859] [<c18e3853>] lpe_mixer_ihf_set+0xb3/0x160 [ 7341.743602] [<c1855b99>] snd_ctl_ioctl+0xa89/0xb40 [ 7341.749052] [<c1331e65>] ? path_openat+0xa5/0x3d0 [ 7341.754409] [<c1447857>] ? avc_has_perm_flags+0xc7/0x170 [ 7341.760441] [<c1855110>] ? snd_ctl_elem_add_user+0x540/0x540 [ 7341.766862] [<c1334047>] do_vfs_ioctl+0x77/0x5e0 [ 7341.772117] [<c144842a>] ? inode_has_perm.isra.42.constprop.79+0x3a/0x50 [ 7341.779705] [<c14490a0>] ? file_has_perm+0xa0/0xb0 [ 7341.785155] [<c14493b8>] ? selinux_file_ioctl+0x48/0xe0 [ 7341.791090] [<c1334628>] SyS_ioctl+0x78/0x90 [ 7341.795958] [<c1a7dde8>] syscall_call+0x7/0xb [ 7341.800925] [<c1a70000>] ? mm_fault_error+0x13c/0x198 Signed-off-by: zhang jun <jun.zhang@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | firmware: google memconsole driver fixesMichel Lespinasse2014-02-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The google memconsole driver is currently broken upstream, as it tries to read memory that is described as reserved in /proc/iomem, by dereferencing a pointer obtained through phys_to_virt(). This triggers a kernel fault as such regions are unmapped after early boot. The proper workaround is to use ioremap_cache() / iounmap() around such accesses. As some unrelated changes, I also converted some printks to use pr_info() and added some missing __init annotations. Tested: booted dbg build, verified I could read /sys/firmware/log Signed-off-by: Michel Lespinasse <walken@google.com> Acked-by: Mike Waychison <mikew@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | firmware: fix google/gsmi duplicate efivars_sysfs_init()Michel Lespinasse2014-02-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Starting in commit e14ab23dde12b80db4c94b684a2e485b72b16af3, efivars_sysfs_init() is called both by itself as an init function, and by drivers/firmware/google/gsmi.c gsmi_init(). This results in runtime warnings such as the following: [ 5.651330] WARNING: at fs/sysfs/dir.c:530 sysfs_add_one+0xbd/0xe0() [ 5.657699] sysfs: cannot create duplicate filename '/firmware/gsmi/vars' Fixing this by removing the redundant efivars_sysfs_init() call in gsmi_init(). Tested: booted, checked that /firmware/gsmi/vars was still present and showed the expected contents. Signed-off-by: Michel Lespinasse <walken@google.com> Acked-by: Matt Fleming <matt.fleming@intel.com> Acked-by: Mike Waychison <mikew@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | drivers/base: delete non-required instances of include <linux/init.h>Paul Gortmaker2014-02-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | None of these files are actually using any __init type directives and hence don't need to include <linux/init.h>. Most are just a left over from __devinit and __cpuinit removal, or simply due to code getting copied from one driver to the next. Cc: Len Brown <len.brown@intel.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Acked-by: Pavel Machek <pavel@ucw.cz> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Mark Brown <broonie@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | kernfs: fix kernfs_node_from_dentry()Li Zefan2014-02-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently kernfs_node_from_dentry() returns NULL for root dentry, because root_dentry->d_op == NULL. Due to this bug cgroupstats_build() returns -EINVAL for root cgroup. # mount -t cgroup -o cpuacct /cgroup # Documentation/accounting/getdelays -C /cgroup fatal reply error, errno -22 With this fix: # Documentation/accounting/getdelays -C /cgroup sleeping 305, blocked 0, running 1, stopped 0, uninterruptible 1 Signed-off-by: Li Zefan <lizefan@huawei.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | ACPI / platform: drop redundant ACPI_HANDLE checkJosh Cartwright2014-02-14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The acpi_dev_pm_attach/_detach functions perform their own checks to ensure the device has an ACPI companion. It is not necessary for the caller to do so. This mirrors what other busses with ACPI dev PM support do (i2c, spi, sdio). Cc: Len Brown <lenb@kernel.org> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Josh Cartwright <joshc@codeaurora.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | Merge branch 'master' into driver-core-next-test-merge-rc2Tejun Heo2014-02-10
| |\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | da9846ae1518 ("kernfs: make kernfs_deactivate() honor KERNFS_LOCKDEP flag") in driver-core-linus conflicts with kernfs_drain() updates in driver-core-next. The former just adds the missing KERNFS_LOCKDEP checks which are already handled by kernfs_lockdep() checks in driver-core-next. The conflict can be resolved by taking code from driver-core-next. Conflicts: fs/kernfs/dir.c
| * | | | kernfs: fix hash calculation in kernfs_rename_ns()Tejun Heo2014-02-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 3eef34ad7dc3 ("kernfs: implement kernfs_get_parent(), kernfs_name/path() and friends") restructured kernfs_rename_ns() such that new name assignment happens under kernfs_rename_lock; unfortunately, it mistakenly passed NULL to kernfs_name_hash() to calculate the new hash if the name hasn't changed, which can lead to oops. Fix it by using kn->name and kn->ns when calculating the new hash. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Dan Carpenter dan.carpenter@oracle.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | | kernfs: add CONFIG_KERNFSTejun Heo2014-02-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As sysfs was kernfs's only user, kernfs has been piggybacking on CONFIG_SYSFS; however, kernfs is scheduled to grow a new user very soon. Introduce a separate config option CONFIG_KERNFS which is to be selected by kernfs users. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: linux-fsdevel@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | | sysfs, kobject: add sysfs wrapper for kernfs_enable_ns()Tejun Heo2014-02-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, kobject is invoking kernfs_enable_ns() directly. This is fine now as sysfs and kernfs are enabled and disabled together. If sysfs is disabled, kernfs_enable_ns() is switched to dummy implementation too and everything is fine; however, kernfs will soon have its own config option CONFIG_KERNFS and !SYSFS && KERNFS will be possible, which can make kobject call into non-dummy kernfs_enable_ns() with NULL kernfs_node pointers leading to an oops. Introduce sysfs_enable_ns() which is a wrapper around kernfs_enable_ns() so that it can be made a noop depending only on CONFIG_SYSFS regardless of the planned CONFIG_KERNFS. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | | kernfs: implement kernfs_get_parent(), kernfs_name/path() and friendsTejun Heo2014-02-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | kernfs_node->parent and ->name are currently marked as "published" indicating that kernfs users may access them directly; however, those fields may get updated by kernfs_rename[_ns]() and unrestricted access may lead to erroneous values or oops. Protect ->parent and ->name updates with a irq-safe spinlock kernfs_rename_lock and implement the following accessors for these fields. * kernfs_name() - format the node's name into the specified buffer * kernfs_path() - format the node's path into the specified buffer * pr_cont_kernfs_name() - pr_cont a node's name (doesn't need buffer) * pr_cont_kernfs_path() - pr_cont a node's path (doesn't need buffer) * kernfs_get_parent() - pin and return a node's parent All can be called under any context. The recursive sysfs_pathname() in fs/sysfs/dir.c is replaced with kernfs_path() and sysfs_rename_dir_ns() is updated to use kernfs_get_parent() instead of dereferencing parent directly. v2: Dummy definition of kernfs_path() for !CONFIG_KERNFS was missing static inline making it cause a lot of build warnings. Add it. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | | kernfs: implement kernfs_node_from_dentry(), kernfs_root_from_sb() and ↵Tejun Heo2014-02-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | kernfs_rename() Implement helpers to determine node from dentry and root from super_block. Also add a kernfs_rename_ns() wrapper which assumes NULL namespace. These generally make sense and will be used by cgroup. v2: Some dummy implementations for !CONFIG_SYSFS was missing. Fixed. Reported by kbuild test robot. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | | kernfs: add kernfs_open_file->privTejun Heo2014-02-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a private data field to be used by kernfs file operations. This generally makes sense and will be used by cgroup. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | | kernfs: implement kernfs_ops->atomic_write_lenTejun Heo2014-02-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A write to a kernfs_node is buffered through a kernel buffer. Writes <= PAGE_SIZE are performed atomically, while larger ones are executed in PAGE_SIZE chunks. While this is enough for sysfs, cgroup which is scheduled to be converted to use kernfs needs a bit more control over it. This patch adds kernfs_ops->atomic_write_len. If not set (zero), the behavior stays the same. If set, writes upto the size are executed atomically and larger writes are rejected with -E2BIG. A different implementation strategy would be allowing configuring chunking size while making the original write size available to the write method; however, such strategy, while being more complicated, doesn't really buy anything. If the write implementation has to handle chunking, the specific chunk size shouldn't matter all that much. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | | kernfs: allow nodes to be created in the deactivated stateTejun Heo2014-02-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, kernfs_nodes are made visible to userland on creation, which makes it difficult for kernfs users to atomically succeed or fail creation of multiple nodes. In addition, if something fails after creating some nodes, the created nodes might already be in use and their active refs need to be drained for removal, which has the potential to introduce tricky reverse locking dependency on active_ref depending on how the error path is synchronized. This patch introduces per-root flag KERNFS_ROOT_CREATE_DEACTIVATED. If set, all nodes under the root are created in the deactivated state and stay invisible to userland until explicitly enabled by the new kernfs_activate() API. Also, nodes which have never been activated are guaranteed to bypass draining on removal thus allowing error paths to not worry about lockding dependency on active_ref draining. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | | kernfs: add missing kernfs_active() checks in directory operationsTejun Heo2014-02-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | kernfs_iop_lookup(), kernfs_dir_pos() and kernfs_dir_next_pos() were missing kernfs_active() tests before using the found kernfs_node. As deactivated state is currently visible only while a node is being removed, this doesn't pose an actual problem. e.g. lookup succeeding on a deactivated node doesn't harm anything as the eventual file operations are gonna fail and those failures are indistinguishible from the cases in which the lookups had happened before the node was deactivated. However, we're gonna allow new nodes to be created deactivated and then activated explicitly by the kernfs user when it sees fit. This is to support atomically making multiple nodes visible to userland and thus those nodes must not be visible to userland before activated. Let's plug the lookup and readdir holes so that deactivated nodes are invisible to userland. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | | kernfs: implement kernfs_syscall_ops->remount_fs() and ->show_options()Tejun Heo2014-02-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add two super_block related syscall callbacks ->remount_fs() and ->show_options() to kernfs_syscall_ops. These simply forward the matching super_operations. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | | kernfs: rename kernfs_dir_ops to kernfs_syscall_opsTejun Heo2014-02-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We're gonna need non-dir syscall callbacks, which will make dir_ops a misnomer. Let's rename kernfs_dir_ops to kernfs_syscall_ops. This is pure rename. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | | kernfs: invoke dir_ops while holding active ref of the target nodeTejun Heo2014-02-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | kernfs_dir_ops are currently being invoked without any active reference, which makes it tricky for the invoked operations to determine whether the objects associated those nodes are safe to access and will remain that way for the duration of such operations. kernfs already has active_ref mechanism to deal with this which makes the removal of a given node the synchronization point for gating the file operations. There's no reason for dir_ops to be any different. Update the dir_ops handling so that active_ref is held while the dir_ops are executing. This guarantees that while a dir_ops is executing the target nodes stay alive. As kernfs_dir_ops doesn't have any in-kernel user at this point, this doesn't affect anybody. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | | sysfs, driver-core: remove unused {sysfs|device}_schedule_callback_owner()Tejun Heo2014-02-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | All device_schedule_callback_owner() users are converted to use device_remove_file_self(). Remove now unused {sysfs|device}_schedule_callback_owner(). Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | | s390: use device_remove_file_self() instead of device_schedule_callback()Tejun Heo2014-02-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | driver-core now supports synchrnous self-deletion of attributes and the asynchrnous removal mechanism is scheduled for removal. Use it instead of device_schedule_callback(). * Conversions in arch/s390/pci/pci_sysfs.c and drivers/s390/block/dcssblk.c are straightforward. * drivers/s390/cio/ccwgroup.c is a bit more tricky because ccwgroup_notifier() was (ab)using device_schedule_callback() to purely obtain a process context to kick off ungroup operation which may block from a notifier callback. Rename ccwgroup_ungroup_callback() to ccwgroup_ungroup() and make it take ccwgroup_device * instead. The new function is now called directly from ccwgroup_ungroup_store(). ccwgroup_notifier() chain is updated to explicitly bounce through ccwgroup_device->ungroup_work. This also removes possible failure from memory pressure. Only compile-tested. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: linux390@de.ibm.com Cc: linux-s390@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | | scsi: use device_remove_file_self() instead of device_schedule_callback()Tejun Heo2014-02-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | driver-core now supports synchrnous self-deletion of attributes and the asynchrnous removal mechanism is scheduled for removal. Use it instead of device_schedule_callback(). This makes "delete" behave synchronously. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: "James E.J. Bottomley" <JBottomley@parallels.com> Cc: linux-scsi@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | | pci: use device_remove_file_self() instead of device_schedule_callback()Tejun Heo2014-02-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | driver-core now supports synchrnous self-deletion of attributes and the asynchrnous removal mechanism is scheduled for removal. Use it instead of device_schedule_callback(). This makes "remove" behave synchronously. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Bjorn Helgaas <bhelgaas@google.com> Cc: linux-pci@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | | kernfs, sysfs, driver-core: implement kernfs_remove_self() and its wrappersTejun Heo2014-02-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Sometimes it's necessary to implement a node which wants to delete nodes including itself. This isn't straightforward because of kernfs active reference. While a file operation is in progress, an active reference is held and kernfs_remove() waits for all such references to drain before completing. For a self-deleting node, this is a deadlock as kernfs_remove() ends up waiting for an active reference that itself is sitting on top of. This currently is worked around in the sysfs layer using sysfs_schedule_callback() which makes such removals asynchronous. While it works, it's rather cumbersome and inherently breaks synchronicity of the operation - the file operation which triggered the operation may complete before the removal is finished (or even started) and the removal may fail asynchronously. If a removal operation is immmediately followed by another operation which expects the specific name to be available (e.g. removal followed by rename onto the same name), there's no way to make the latter operation reliable. The thing is there's no inherent reason for this to be asynchrnous. All that's necessary to do this synchronous is a dedicated operation which drops its own active ref and deactivates self. This patch implements kernfs_remove_self() and its wrappers in sysfs and driver core. kernfs_remove_self() is to be called from one of the file operations, drops the active ref the task is holding, removes the self node, and restores active ref to the dead node so that the ref is balanced afterwards. __kernfs_remove() is updated so that it takes an early exit if the target node is already fully removed so that the active ref restored by kernfs_remove_self() after removal doesn't confuse the deactivation path. This makes implementing self-deleting nodes very easy. The normal removal path doesn't even need to be changed to use kernfs_remove_self() for the self-deleting node. The method can invoke kernfs_remove_self() on itself before proceeding the normal removal path. kernfs_remove() invoked on the node by the normal deletion path will simply be ignored. This will replace sysfs_schedule_callback(). A subtle feature of sysfs_schedule_callback() is that it collapses multiple invocations - even if multiple removals are triggered, the removal callback is run only once. An equivalent effect can be achieved by testing the return value of kernfs_remove_self() - only the one which gets %true return value should proceed with actual deletion. All other instances of kernfs_remove_self() will wait till the enclosing kernfs operation which invoked the winning instance of kernfs_remove_self() finishes and then return %false. This trivially makes all users of kernfs_remove_self() automatically show correct synchronous behavior even when there are multiple concurrent operations - all "echo 1 > delete" instances will finish only after the whole operation is completed by one of the instances. Note that manipulation of active ref is implemented in separate public functions - kernfs_[un]break_active_protection(). kernfs_remove_self() is the only user at the moment but this will be used to cater to more complex cases. v2: For !CONFIG_SYSFS, dummy version kernfs_remove_self() was missing and sysfs_remove_file_self() had incorrect return type. Fix it. Reported by kbuild test bot. v3: kernfs_[un]break_active_protection() separated out from kernfs_remove_self() and exposed as public API. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Alan Stern <stern@rowland.harvard.edu> Cc: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | | kernfs: remove KERNFS_REMOVEDTejun Heo2014-02-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | KERNFS_REMOVED is used to mark half-initialized and dying nodes so that they don't show up in lookups and deny adding new nodes under or renaming it; however, its role overlaps that of deactivation. It's necessary to deny addition of new children while removal is in progress; however, this role considerably intersects with deactivation - KERNFS_REMOVED prevents new children while deactivation prevents new file operations. There's no reason to have them separate making things more complex than necessary. This patch removes KERNFS_REMOVED. * Instead of KERNFS_REMOVED, each node now starts its life deactivated. This means that we now use both atomic_add() and atomic_sub() on KN_DEACTIVATED_BIAS, which is INT_MIN. The compiler generates an overflow warnings when negating INT_MIN as the negation can't be represented as a positive number. Nothing is actually broken but let's bump BIAS by one to avoid the warnings for archs which negates the subtrahend.. * A new helper kernfs_active() which tests whether kn->active >= 0 is added for convenience and lockdep annotation. All KERNFS_REMOVED tests are replaced with negated kernfs_active() tests. * __kernfs_remove() is updated to deactivate, but not drain, all nodes in the subtree instead of setting KERNFS_REMOVED. This removes deactivation from kernfs_deactivate(), which is now renamed to kernfs_drain(). * Sanity check on KERNFS_REMOVED in kernfs_put() is replaced with checks on the active ref. * Some comment style updates in the affected area. v2: Reordered before removal path restructuring. kernfs_active() dropped and kernfs_get/put_active() used instead. RB_EMPTY_NODE() used in the lookup paths. v3: Reverted most of v2 except for creating a new node with KN_DEACTIVATED_BIAS. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | | kernfs: remove KERNFS_ACTIVE_REF and add kernfs_lockdep()Tejun Heo2014-02-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There currently are two mechanisms gating active ref lockdep annotations - KERNFS_LOCKDEP flag and KERNFS_ACTIVE_REF type mask. The former disables lockdep annotations in kernfs_get/put_active() while the latter disables all of kernfs_deactivate(). While KERNFS_ACTIVE_REF also behaves as an optimization to skip the deactivation step for non-file nodes, the benefit is marginal and it needlessly diverges code paths. Let's drop KERNFS_ACTIVE_REF. While at it, add a test helper kernfs_lockdep() to test KERNFS_LOCKDEP flag so that it's more convenient and the related code can be compiled out when not enabled. v2: Refreshed on top of ("kernfs: make kernfs_deactivate() honor KERNFS_LOCKDEP flag"). As the earlier patch already added KERNFS_LOCKDEP tests to kernfs_deactivate(), those additions are dropped from this patch and the existing ones are simply converted to kernfs_lockdep(). Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | | kernfs: remove kernfs_addrm_cxtTejun Heo2014-02-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | kernfs_addrm_cxt and the accompanying kernfs_addrm_start/finish() were added because there were operations which should be performed outside kernfs_mutex after adding and removing kernfs_nodes. The necessary operations were recorded in kernfs_addrm_cxt and performed by kernfs_addrm_finish(); however, after the recent changes which relocated deactivation and unmapping so that they're performed directly during removal, the only operation kernfs_addrm_finish() performs is kernfs_put(), which can be moved inside the removal path too. This patch moves the kernfs_put() of the base ref to __kernfs_remove() and remove kernfs_addrm_cxt and kernfs_addrm_start/finish(). * kernfs_add_one() is updated to grab and release kernfs_mutex itself. sysfs_addrm_start/finish() invocations around it are removed from all users. * __kernfs_remove() puts an unlinked node directly instead of chaining it to kernfs_addrm_cxt. Its callers are updated to grab and release kernfs_mutex instead of calling kernfs_addrm_start/finish() around it. v2: Rebased on top of "kernfs: associate a new kernfs_node with its parent on creation" which dropped @parent from kernfs_add_one(). Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | | kernfs: invoke kernfs_unmap_bin_file() directly from kernfs_deactivate()Tejun Heo2014-02-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | kernfs_unmap_bin_file() is supposed to unmap all memory mappings of the target file before kernfs_remove() finishes; however, it currently is being called from kernfs_addrm_finish() and has the same race problem as the original implementation of deactivation when there are multiple removers - only the remover which snatches the node to its addrm_cxt->removed list is guaranteed to wait for its completion before returning. It can be easily fixed by moving kernfs_unmap_bin_file() invocation from kernfs_addrm_finish() to kernfs_deactivated(). The function may be called multiple times but that shouldn't do any harm. Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | | kernfs: restructure removal path to fix possible premature returnTejun Heo2014-02-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The recursive nature of kernfs_remove() means that, even if kernfs_remove() is not allowed to be called multiple times on the same node, there may be race conditions between removal of parent and its descendants. While we can claim that kernfs_remove() shouldn't be called on one of the descendants while the removal of an ancestor is in progress, such rule is unnecessarily restrictive and very difficult to enforce. It's better to simply allow invoking kernfs_remove() as the caller sees fit as long as the caller ensures that the node is accessible. The current behavior in such situations is broken. Whoever enters removal path first takes the node off the hierarchy and then deactivates. Following removers either return as soon as it notices that it's not the first one or can't even find the target node as it has already been removed from the hierarchy. In both cases, the following removers may finish prematurely while the nodes which should be removed and drained are still being processed by the first one. This patch restructures so that multiple removers, whether through recursion or direction invocation, always follow the following rules. * When there are multiple concurrent removers, only one puts the base ref. * Regardless of which one puts the base ref, all removers are blocked until the target node is fully deactivated and removed. To achieve the above, removal path now first marks all descendants including self REMOVED and then deactivates and unlinks leftmost descendant one-by-one. kernfs_deactivate() is called directly from __kernfs_removal() and drops and regrabs kernfs_mutex for each descendant to drain active refs. As this means that multiple removers can enter kernfs_deactivate() for the same node, the function is updated so that it can handle multiple deactivators of the same node - only one actually deactivates but all wait till drain completion. The restructured removal path guarantees that a removed node gets unlinked only after the node is deactivated and drained. Combined with proper multiple deactivator handling, this guarantees that any invocation of kernfs_remove() returns only after the node itself and all its descendants are deactivated, drained and removed. v2: Draining separated into a separate loop (used to be in the same loop as unlink) and done from __kernfs_deactivate(). This is to allow exposing deactivation as a separate interface later. Root node removal was broken in v1 patch. Fixed. v3: Revert most of v2 except for root node removal fix and simplification of KERNFS_REMOVED setting loop. v4: Refreshed on top of ("kernfs: make kernfs_deactivate() honor KERNFS_LOCKDEP flag"). Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | | kernfs: replace kernfs_node->u.completion with kernfs_root->deactivate_waitqTejun Heo2014-02-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | kernfs_node->u.completion is used to notify deactivation completion from kernfs_put_active() to kernfs_deactivate(). We now allow multiple racing removals of the same node and the current removal scheme is no longer correct - kernfs_remove() invocation may return before the node is properly deactivated if it races against another removal. The removal path will be restructured to address the issue. To help such restructure which requires supporting multiple waiters, this patch replaces kernfs_node->u.completion with kernfs_root->deactivate_waitq. This makes deactivation event notifications share a per-root waitqueue_head; however, the wait path is quite cold and this will also allow shaving one pointer off kernfs_node. v2: Refreshed on top of ("kernfs: make kernfs_deactivate() honor KERNFS_LOCKDEP flag"). Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | | kernfs: make kernfs_deactivate() honor KERNFS_LOCKDEP flagTejun Heo2014-02-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | kernfs_deactivate() forgot to check whether KERNFS_LOCKDEP is set before performing lockdep annotations and ends up feeding uninitialized lockdep_map to lockdep triggering warning like the following on USB stick hotunplug. usb 1-2: USB disconnect, device number 2 INFO: trying to register non-static key. the code is fine but needs lockdep annotation. turning off the locking correctness validator. CPU: 1 PID: 62 Comm: khubd Not tainted 3.13.0-work+ #82 Hardware name: empty empty/S3992, BIOS 080011 10/26/2007 ffff880065ca7f60 ffff88013a4ffa08 ffffffff81cfb6bd 0000000000000002 ffff88013a4ffac8 ffffffff810f8530 ffff88013a4fc710 0000000000000002 ffff880100000000 ffffffff82a3db50 0000000000000001 ffff88013a4fc710 Call Trace: [<ffffffff81cfb6bd>] dump_stack+0x4e/0x7a [<ffffffff810f8530>] __lock_acquire+0x1910/0x1e70 [<ffffffff810f931a>] lock_acquire+0x9a/0x1d0 [<ffffffff8127c75e>] kernfs_deactivate+0xee/0x130 [<ffffffff8127d4c8>] kernfs_addrm_finish+0x38/0x60 [<ffffffff8127d701>] kernfs_remove_by_name_ns+0x51/0xa0 [<ffffffff8127b4f1>] remove_files.isra.1+0x41/0x80 [<ffffffff8127b7e7>] sysfs_remove_group+0x47/0xa0 [<ffffffff8127b873>] sysfs_remove_groups+0x33/0x50 [<ffffffff8177d66d>] device_remove_attrs+0x4d/0x80 [<ffffffff8177e25e>] device_del+0x12e/0x1d0 [<ffffffff819722c2>] usb_disconnect+0x122/0x1a0 [<ffffffff819749b5>] hub_thread+0x3c5/0x1290 [<ffffffff810c6a6d>] kthread+0xed/0x110 [<ffffffff81d0a56c>] ret_from_fork+0x7c/0xb0 Fix it by making kernfs_deactivate() perform lockdep annotations only if KERNFS_LOCKDEP is set. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Fabio Estevam <festevam@gmail.com> Reported-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| * | | | dma-buf: avoid using IS_ERR_OR_NULLColin Cross2014-02-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | dma_buf_map_attachment and dma_buf_vmap can return NULL or ERR_PTR on a error. This encourages a common buggy pattern in callers: sgt = dma_buf_map_attachment(attach, DMA_BIDIRECTIONAL); if (IS_ERR_OR_NULL(sgt)) return PTR_ERR(sgt); This causes the caller to return 0 on an error. IS_ERR_OR_NULL is almost always a sign of poorly-defined error handling. This patch converts dma_buf_map_attachment to always return ERR_PTR, and fixes the callers that incorrectly handled NULL. There are a few more callers that were not checking for NULL at all, which would have dereferenced a NULL pointer later. There are also a few more callers that correctly handled NULL and ERR_PTR differently, I left those alone but they could also be modified to delete the NULL check. This patch also converts dma_buf_vmap to always return NULL. All the callers to dma_buf_vmap only check for NULL, and would have dereferenced an ERR_PTR and panic'd if one was ever returned. This is not consistent with the rest of the dma buf APIs, but matches the expectations of all of the callers. Signed-off-by: Colin Cross <ccross@android.com> Reviewed-by: Rob Clark <robdclark@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | | | | Merge tag 'char-misc-3.15-rc1' of ↵Linus Torvalds2014-04-01
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char/misc driver patches from Greg KH: "Here's the big char/misc driver updates for 3.15-rc1. Lots of various things here, including the new mcb driver subsystem. All of these have been in linux-next for a while" * tag 'char-misc-3.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (118 commits) extcon: Move OF helper function to extcon core and change function name extcon: of: Remove unnecessary function call by using the name of device_node extcon: gpio: Use SIMPLE_DEV_PM_OPS macro extcon: palmas: Use SIMPLE_DEV_PM_OPS macro mei: don't use deprecated DEFINE_PCI_DEVICE_TABLE macro mei: amthif: fix checkpatch error mei: client.h fix checkpatch errors mei: use cl_dbg where appropriate mei: fix Unnecessary space after function pointer name mei: report consistently copy_from/to_user failures mei: drop pr_fmt macros mei: make me hw headers private to me hw. mei: fix memory leak of pending write cb objects mei: me: do not reset when less than expected data is received drivers: mcb: Fix build error discovered by 0-day bot cs5535-mfgpt: Simplify dependencies spmi: pm: drop bus-level PM suspend/resume routines spmi: pmic_arb: make selectable on ARCH_QCOM Drivers: hv: vmbus: Increase the limit on the number of pfns we can handle pch_phub: Report error writing MAC back to user ...
| * \ \ \ \ Merge tag 'extcon-next-for-3.15' of ↵Greg Kroah-Hartman2014-03-19
| |\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/chanwoo/extcon into char-misc-next Chanwoo writes: Update extcon for v3.15 This patchset fix minor issue. The extcon-palmas/gpio use SIMPLE_DEV_PM_OPS macro instead of legacy method. OF helper function of extcon move in extcon core to remove separate of_extcon.c and change the name of OF helper function as following because previous function name is complicated and ambiguous naming. - of_extcon_get_extcon_dev() -> extcon_get_edev_by_phandle()
| | * | | | | extcon: Move OF helper function to extcon core and change function nameChanwoo Choi2014-03-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch move simply OF helper function to extcon core and change function name as following: - of_extcon_get_extcon_dev() -> extcon_get_edev_by_phandle() Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com> Acked-by: Felipe Balbi <balbi@ti.com>
| | * | | | | extcon: of: Remove unnecessary function call by using the name of device_nodeChanwoo Choi2014-03-19
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch remove unnecessary function call in of_extcon_get_extcon_dev() by using the name of device_node structure. Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>