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2012-06-06mac80211: unify SW/offload remain-on-channelJohannes Berg
Redesign all the off-channel code, getting rid of the generic off-channel work concept, replacing it with a simple remain-on-channel list. This fixes a number of small issues with the ROC implementation: * offloaded remain-on-channel couldn't be queued, now we can queue it as well, if needed * in iwlwifi (the only user) offloaded ROC is mutually exclusive with scanning, use the new queue to handle that case -- I expect that it will later depend on a HW flag The bigger issue though is that there's a bad bug in the current implementation: if we get a mgmt TX request while HW roc is active, and this new request has a wait time, we actually schedule a software ROC instead since we can't guarantee the existing offloaded ROC will still be that long. To fix this, the queuing mechanism was needed. The queuing mechanism for offloaded ROC isn't yet optimal, ideally we should add API to have the HW extend the ROC if needed. We could add that later but for now use a software implementation. Overall, this unifies the behaviour between the offloaded and software-implemented case as much as possible. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2012-06-06mac80211: do remain-on-channel while idleJohannes Berg
The IDLE handling in HW off-channel is broken right now since we turn off IDLE only when the off-channel period already started. Therefore, all drivers that use it today (only iwlwifi!) must support off-channel while idle, so playing with idle isn't needed at all. Off-channel in general, since it's no longer used for authentication/association, shouldn't affect PS, so also remove that logic. Also document a small caveat for reporting TX status from off-channel frames in HW remain-on-channel. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2012-06-06cfg80211: validate remain-on-channel time betterJohannes Berg
The remain-on-channel time validation shouldn't depend on the value of HZ, as it does now with the check against jiffies, since then you might use a value that works on one system but not on another. Fix it by checking against a minimum that's fixed. Also add validation of the wait duration for a management frame TX since this also translates into remain-on-channel internally. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2012-06-06ssb: recognize ARM Cortex M3Hauke Mehrtens
I found this core on a BCM4322, a PCI card in the Linksys WRT610N V1. This core is not used by the driver, this patch just makes ssb show the correct name. Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2012-06-06cfg80211: clarify set_channel APIsJohannes Berg
Now that we've removed all uses of the set_channel API except for the monitor channel and in libertas, clarify this. Split the libertas mesh use into a new libertas_set_mesh_channel() operation, just to keep backward compatibility, and rename the normal set_channel() to set_monitor_channel(). Also describe the desired set_monitor_channel() semantics more clearly. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2012-06-05cfg80211: provide channel to join_mesh functionJohannes Berg
Just like the AP mode patch, instead of setting the channel and then joining the mesh network, provide the channel to join the network on to the join_mesh() function. Like in AP mode, you can also give the channel to the join-mesh nl80211 command now. Unlike AP mode, it picks a default channel if none was given. As libertas uses mesh mode interfaces but has no join_mesh callback and we can't simply break it, keep some compatibility code for that case and configure the channel directly for it. In the non-libertas case, where we store the channel until join, allow setting it while the interface is down. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2012-06-05cfg80211: provide channel to start_ap functionJohannes Berg
Instead of setting the channel first and then starting the AP, let cfg80211 store the channel and provide it as one of the AP settings. This means that now you have to set the channel before you can start an AP interface, but since hostapd/wpa_supplicant always do that we're OK with this change. Alternatively, it's now possible to give the channel as an attribute to the start-ap nl80211 command, overriding any preset channel. Cc: Kalle Valo <kvalo@qca.qualcomm.com> Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2012-06-05cfg80211: simplify cfg80211_can_beacon_sec_chan APIJohannes Berg
Change cfg80211_can_beacon_sec_chan() to return true if there is no secondary channel to simplify all the current users of it. They all check the channel type before calling the function because it returns false if there's no secondary channel. Also actually document the return value. Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2012-06-05mac80211: remove ieee80211_get_operstate()Eliad Peller
ieee80211_get_operstate() was used by drivers in order to know whether the sta link is up, but it's no longer needed (nor used) as mac80211 notifies the drivers about authorization changes (via the sta_state callback) Signed-off-by: Eliad Peller <eliad@wizery.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2012-06-05net: mac80211: Add and use ibss_vdbg debugging macroJoe Perches
Simplify the use of #ifdef CONFIG_MAC80211_IBSS_DEBUG/#endif by adding a logging macro to encapsulate the test. Convert the appropriate uses too. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2012-06-05net: mac80211: Add and use ht_vdbg debugging macroJoe Perches
Simplify the use of #ifdef CONFIG_MAC80211_HT_DEBUG/#endif by adding a logging macro to encapsulate the test. Convert the appropriate uses too. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2012-06-05nl80211: add new rssi event to indicate beacon lossEliad Peller
Tell userspace about beacon loss event. This event doesn't replace the deauth/disassoc that might come if the AP is not available. The driver can send this event in order to hint userspace what might follow (which in turn can use it as roaming trigger). Signed-off-by: Eliad Peller <eliad@wizery.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2012-06-05mac80211: allow low-level drivers to set netdev feature bitsArik Nemtsov
Low level drivers can now set certain netdev feature bits in netdev_features member of the ieee80211_hw struct. These will be propagated to every netdev created from this HW. The white-listed features currently include only ones related to HW checksumming. Signed-off-by: Arik Nemtsov <arik@wizery.com> Signed-off-by: John W. Linville <linville@tuxdriver.com>
2012-06-02Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds
Pull networking updates from David Miller: 1) Make syn floods consume significantly less resources by a) Not pre-COW'ing routing metrics for SYN/ACKs b) Mirroring the device queue mapping of the SYN for the SYN/ACK reply. Both from Eric Dumazet. 2) Fix calculation errors in Byte Queue Limiting, from Hiroaki SHIMODA. 3) Validate the length requested when building a paged SKB for a socket, so we don't overrun the page vector accidently. From Jason Wang. 4) When netlabel is disabled, we abort all IP option processing when we see a CIPSO option. This isn't the right thing to do, we should simply skip over it and continue processing the remaining options (if any). Fix from Paul Moore. 5) SRIOV fixes for the mellanox driver from Jack orgenstein and Marcel Apfelbaum. 6) 8139cp enables the receiver before the ring address is properly programmed, which potentially lets the device crap over random memory. Fix from Jason Wang. 7) e1000/e1000e fixes for i217 RST handling, and an improper buffer address reference in jumbo RX frame processing from Bruce Allan and Sebastian Andrzej Siewior, respectively. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: fec_mpc52xx: fix timestamp filtering mcs7830: Implement link state detection e1000e: fix Rapid Start Technology support for i217 e1000: look into the page instead of skb->data for e1000_tbi_adjust_stats() r8169: call netif_napi_del at errpaths and at driver unload tcp: reflect SYN queue_mapping into SYNACK packets tcp: do not create inetpeer on SYNACK message 8139cp/8139too: terminate the eeprom access with the right opmode 8139cp: set ring address before enabling receiver cipso: handle CIPSO options correctly when NetLabel is disabled net: sock: validate data_len before allocating skb in sock_alloc_send_pskb() bql: Avoid possible inconsistent calculation. bql: Avoid unneeded limit decrement. bql: Fix POSDIFF() to integer overflow aware. net/mlx4_core: Fix obscure mlx4_cmd_box parameter in QUERY_DEV_CAP net/mlx4_core: Check port out-of-range before using in mlx4_slave_cap net/mlx4_core: Fixes for VF / Guest startup flow net/mlx4_en: Fix improper use of "port" parameter in mlx4_en_event net/mlx4_core: Fix number of EQs used in ICM initialisation net/mlx4_core: Fix the slave_id out-of-range test in mlx4_eq_int
2012-06-02tty: Revert the tty locking series, it needs more workLinus Torvalds
This reverts the tty layer change to use per-tty locking, because it's not correct yet, and fixing it will require some more deep surgery. The main revert is d29f3ef39be4 ("tty_lock: Localise the lock"), but there are several smaller commits that built upon it, they also get reverted here. The list of reverted commits is: fde86d310886 - tty: add lockdep annotations 8f6576ad476b - tty: fix ldisc lock inversion trace d3ca8b64b97e - pty: Fix lock inversion b1d679afd766 - tty: drop the pty lock during hangup abcefe5fc357 - tty/amiserial: Add missing argument for tty_unlock() fd11b42e3598 - cris: fix missing tty arg in wait_event_interruptible_tty call d29f3ef39be4 - tty_lock: Localise the lock The revert had a trivial conflict in the 68360serial.c staging driver that got removed in the meantime. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-06-01Merge tag 'fbdev-updates-for-3.5' of git://github.com/schandinat/linux-2.6Linus Torvalds
Pull fbdev updates from Florian Tobias Schandinat: - driver for AUO-K1900 and AUO-K1901 epaper controller - large updates for OMAP (e.g. decouple HDMI audio and video) - some updates for Exynos and SH Mobile - various other small fixes and cleanups * tag 'fbdev-updates-for-3.5' of git://github.com/schandinat/linux-2.6: (130 commits) video: bfin_adv7393fb: Fix cleanup code video: exynos_dp: reduce delay time when configuring video setting video: exynos_dp: move sw reset prioir to enabling sw defined function video: exynos_dp: use devm_ functions fb: handle NULL pointers in framebuffer release OMAPDSS: HDMI: OMAP4: Update IRQ flags for the HPD IRQ request OMAPDSS: Apply VENC timings even if panel is disabled OMAPDSS: VENC/DISPC: Delay dividing Y resolution for managers connected to VENC OMAPDSS: DISPC: Support rotation through TILER OMAPDSS: VRFB: remove compiler warnings when CONFIG_BUG=n OMAPFB: remove compiler warnings when CONFIG_BUG=n OMAPDSS: remove compiler warnings when CONFIG_BUG=n OMAPDSS: DISPC: fix usage of dispc_ovl_set_accu_uv OMAPDSS: use DSI_FIFO_BUG workaround only for manual update displays OMAPDSS: DSI: Support command mode interleaving during video mode blanking periods OMAPDSS: DISPC: Update Accumulator configuration for chroma plane drivers/video: fsl-diu-fb: don't initialize the THRESHOLDS registers video: exynos mipi dsi: support reverse panel type video: exynos mipi dsi: Properly interpret the interrupt source flags video: exynos mipi dsi: Avoid races in probe() ...
2012-06-01Merge tag 'for-linus-3.5-20120601' of git://git.infradead.org/linux-mtdLinus Torvalds
Pull mtd update from David Woodhouse: - More robust parsing especially of xattr data in JFFS2 - Updates to mxc_nand and gpmi drivers to support new boards and device tree - Improve consistency of information about ECC strength in NAND devices - Clean up partition handling of plat_nand - Support NAND drivers without dedicated access to OOB area - BCH hardware ECC support for OMAP - Other fixes and cleanups, and a few new device IDs Fixed trivial conflict in drivers/mtd/nand/gpmi-nand/gpmi-nand.c due to added include files next to each other. * tag 'for-linus-3.5-20120601' of git://git.infradead.org/linux-mtd: (75 commits) mtd: mxc_nand: move ecc strengh setup before nand_scan_tail mtd: block2mtd: fix recursive call of mtd_writev mtd: gpmi-nand: define ecc.strength mtd: of_parts: fix breakage in Kconfig mtd: nand: fix scan_read_raw_oob mtd: docg3 fix in-middle of blocks reads mtd: cfi_cmdset_0002: Slight cleanup of fixup messages mtd: add fixup for S29NS512P NOR flash. jffs2: allow to complete xattr integrity check on first GC scan jffs2: allow to discriminate between recoverable and non-recoverable errors mtd: nand: omap: add support for hardware BCH ecc ARM: OMAP3: gpmc: add BCH ecc api and modes mtd: nand: check the return code of 'read_oob/read_oob_raw' mtd: nand: remove 'sndcmd' parameter of 'read_oob/read_oob_raw' mtd: m25p80: Add support for Winbond W25Q80BW jffs2: get rid of jffs2_sync_super jffs2: remove unnecessary GC pass on sync jffs2: remove unnecessary GC pass on umount jffs2: remove lock_super mtd: gpmi: add gpmi support for mx6q ...
2012-06-01Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal Pull third pile of signal handling patches from Al Viro: "This time it's mostly helpers and conversions to them; there's a lot of stuff remaining in the tree, but that'll either go in -rc2 (isolated bug fixes, ideally via arch maintainers' trees) or will sit there until the next cycle." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: x86: get rid of calling do_notify_resume() when returning to kernel mode blackfin: check __get_user() return value whack-a-mole with TIF_FREEZE FRV: Optimise the system call exit path in entry.S [ver #2] FRV: Shrink TIF_WORK_MASK [ver #2] FRV: Prevent syscall exit tracing and notify_resume at end of kernel exceptions new helper: signal_delivered() powerpc: get rid of restore_sigmask() most of set_current_blocked() callers want SIGKILL/SIGSTOP removed from set set_restore_sigmask() is never called without SIGPENDING (and never should be) TIF_RESTORE_SIGMASK can be set only when TIF_SIGPENDING is set don't call try_to_freeze() from do_signal() pull clearing RESTORE_SIGMASK into block_sigmask() sh64: failure to build sigframe != signal without handler openrisc: tracehook_signal_handler() is supposed to be called on success new helper: sigmask_to_save() new helper: restore_saved_sigmask() new helpers: {clear,test,test_and_clear}_restore_sigmask() HAVE_RESTORE_SIGMASK is defined on all architectures now
2012-06-01cipso: handle CIPSO options correctly when NetLabel is disabledPaul Moore
When NetLabel is not enabled, e.g. CONFIG_NETLABEL=n, and the system receives a CIPSO tagged packet it is dropped (cipso_v4_validate() returns non-zero). In most cases this is the correct and desired behavior, however, in the case where we are simply forwarding the traffic, e.g. acting as a network bridge, this becomes a problem. This patch fixes the forwarding problem by providing the basic CIPSO validation code directly in ip_options_compile() without the need for the NetLabel or CIPSO code. The new validation code can not perform any of the CIPSO option label/value verification that cipso_v4_validate() does, but it can verify the basic CIPSO option format. The behavior when NetLabel is enabled is unchanged. Signed-off-by: Paul Moore <pmoore@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-01Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs changes from Al Viro. "A lot of misc stuff. The obvious groups: * Miklos' atomic_open series; kills the damn abuse of ->d_revalidate() by NFS, which was the major stumbling block for all work in that area. * ripping security_file_mmap() and dealing with deadlocks in the area; sanitizing the neighborhood of vm_mmap()/vm_munmap() in general. * ->encode_fh() switched to saner API; insane fake dentry in mm/cleancache.c gone. * assorted annotations in fs (endianness, __user) * parts of Artem's ->s_dirty work (jff2 and reiserfs parts) * ->update_time() work from Josef. * other bits and pieces all over the place. Normally it would've been in two or three pull requests, but signal.git stuff had eaten a lot of time during this cycle ;-/" Fix up trivial conflicts in Documentation/filesystems/vfs.txt (the 'truncate_range' inode method was removed by the VM changes, the VFS update adds an 'update_time()' method), and in fs/btrfs/ulist.[ch] (due to sparse fix added twice, with other changes nearby). * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (95 commits) nfs: don't open in ->d_revalidate vfs: retry last component if opening stale dentry vfs: nameidata_to_filp(): don't throw away file on error vfs: nameidata_to_filp(): inline __dentry_open() vfs: do_dentry_open(): don't put filp vfs: split __dentry_open() vfs: do_last() common post lookup vfs: do_last(): add audit_inode before open vfs: do_last(): only return EISDIR for O_CREAT vfs: do_last(): check LOOKUP_DIRECTORY vfs: do_last(): make ENOENT exit RCU safe vfs: make follow_link check RCU safe vfs: do_last(): use inode variable vfs: do_last(): inline walk_component() vfs: do_last(): make exit RCU safe vfs: split do_lookup() Btrfs: move over to use ->update_time fs: introduce inode operation ->update_time reiserfs: get rid of resierfs_sync_super reiserfs: mark the superblock as dirty a bit later ...
2012-06-01Merge tag 'ext4_for_linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 Pull Ext4 updates from Theodore Ts'o: "The major new feature added in this update is Darrick J Wong's metadata checksum feature, which adds crc32 checksums to ext4's metadata fields. There is also the usual set of cleanups and bug fixes." * tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (44 commits) ext4: hole-punch use truncate_pagecache_range jbd2: use kmem_cache_zalloc wrapper instead of flag ext4: remove mb_groups before tearing down the buddy_cache ext4: add ext4_mb_unload_buddy in the error path ext4: don't trash state flags in EXT4_IOC_SETFLAGS ext4: let getattr report the right blocks in delalloc+bigalloc ext4: add missing save_error_info() to ext4_error() ext4: add debugging trigger for ext4_error() ext4: protect group inode free counting with group lock ext4: use consistent ssize_t type in ext4_file_write() ext4: fix format flag in ext4_ext_binsearch_idx() ext4: cleanup in ext4_discard_allocated_blocks() ext4: return ENOMEM when mounts fail due to lack of memory ext4: remove redundundant "(char *) bh->b_data" casts ext4: disallow hard-linked directory in ext4_lookup ext4: fix potential integer overflow in alloc_flex_gd() ext4: remove needs_recovery in ext4_mb_init() ext4: force ro mount if ext4_setup_super() fails ext4: fix potential NULL dereference in ext4_free_inodes_counts() ext4/jbd2: add metadata checksumming to the list of supported features ...
2012-06-01new helper: signal_delivered()Al Viro
Does block_sigmask() + tracehook_signal_handler(); called when sigframe has been successfully built. All architectures converted to it; block_sigmask() itself is gone now (merged into this one). I'm still not too happy with the signature, but that's a separate story (IMO we need a structure that would contain signal number + siginfo + k_sigaction, so that get_signal_to_deliver() would fill one, signal_delivered(), handle_signal() and probably setup...frame() - take one). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01most of set_current_blocked() callers want SIGKILL/SIGSTOP removed from setAl Viro
Only 3 out of 63 do not. Renamed the current variant to __set_current_blocked(), added set_current_blocked() that will exclude unblockable signals, switched open-coded instances to it. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01set_restore_sigmask() is never called without SIGPENDING (and never should be)Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01new helper: sigmask_to_save()Al Viro
replace boilerplate "should we use ->saved_sigmask or ->blocked?" with calls of obvious inlined helper... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01new helper: restore_saved_sigmask()Al Viro
first fruits of ..._restore_sigmask() helpers: now we can take boilerplate "signal didn't have a handler, clear RESTORE_SIGMASK and restore the blocked mask from ->saved_mask" into a common helper. Open-coded instances switched... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01new helpers: {clear,test,test_and_clear}_restore_sigmask()Al Viro
helpers parallel to set_restore_sigmask(), used in the next commits Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01HAVE_RESTORE_SIGMASK is defined on all architectures nowAl Viro
Everyone either defines it in arch thread_info.h or has TIF_RESTORE_SIGMASK and picks default set_restore_sigmask() in linux/thread_info.h. Kill the ifdefs, slap #error in linux/thread_info.h to catch breakage when new ones get merged. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01vfs: retry last component if opening stale dentryMiklos Szeredi
NFS optimizes away d_revalidates for last component of open. This means that open itself can find the dentry stale. This patch allows the filesystem to return EOPENSTALE and the VFS will retry the lookup on just the last component if possible. If the lookup was done using RCU mode, including the last component, then this is not possible since the parent dentry is lost. In this case fall back to non-RCU lookup. Currently this is not used since NFS will always leave RCU mode. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01fs: introduce inode operation ->update_timeJosef Bacik
Btrfs has to make sure we have space to allocate new blocks in order to modify the inode, so updating time can fail. We've gotten around this by having our own file_update_time but this is kind of a pain, and Christoph has indicated he would like to make xfs do something different with atime updates. So introduce ->update_time, where we will deal with i_version an a/m/c time updates and indicate which changes need to be made. The normal version just does what it has always done, updates the time and marks the inode dirty, and then filesystems can choose to do something different. I've gone through all of the users of file_update_time and made them check for errors with the exception of the fault code since it's complicated and I wasn't quite sure what to do there, also Jan is going to be pushing the file time updates into page_mkwrite for those who have it so that should satisfy btrfs and make it not a big deal to check the file_update_time() return code in the generic fault path. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com>
2012-06-01Merge branch 'for-3.5' of git://linux-nfs.org/~bfields/linuxLinus Torvalds
Pull the rest of the nfsd commits from Bruce Fields: "... and then I cherry-picked the remainder of the patches from the head of my previous branch" This is the rest of the original nfsd branch, rebased without the delegation stuff that I thought really needed to be redone. I don't like rebasing things like this in general, but in this situation this was the lesser of two evils. * 'for-3.5' of git://linux-nfs.org/~bfields/linux: (50 commits) nfsd4: fix, consolidate client_has_state nfsd4: don't remove rebooted client record until confirmation nfsd4: remove some dprintk's and a comment nfsd4: return "real" sequence id in confirmed case nfsd4: fix exchange_id to return confirm flag nfsd4: clarify that renewing expired client is a bug nfsd4: simpler ordering of setclientid_confirm checks nfsd4: setclientid: remove pointless assignment nfsd4: fix error return in non-matching-creds case nfsd4: fix setclientid_confirm same_cred check nfsd4: merge 3 setclientid cases to 2 nfsd4: pull out common code from setclientid cases nfsd4: merge last two setclientid cases nfsd4: setclientid/confirm comment cleanup nfsd4: setclientid remove unnecessary terms from a logical expression nfsd4: move rq_flavor into svc_cred nfsd4: stricter cred comparison for setclientid/exchange_id nfsd4: move principal name into svc_cred nfsd4: allow removing clients not holding state nfsd4: rearrange exchange_id logic to simplify ...
2012-06-01switch aio and shm to do_mmap_pgoff(), make do_mmap() staticAl Viro
after all, 0 bytes and 0 pages is the same thing... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-06-01take security_mmap_file() outside of ->mmap_semAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-31Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal Pull second pile of signal handling patches from Al Viro: "This one is just task_work_add() series + remaining prereqs for it. There probably will be another pull request from that tree this cycle - at least for helpers, to get them out of the way for per-arch fixes remaining in the tree." Fix trivial conflict in kernel/irq/manage.c: the merge of Andrew's pile had brought in commit 97fd75b7b8e0 ("kernel/irq/manage.c: use the pr_foo() infrastructure to prefix printks") which changed one of the pr_err() calls that this merge moves around. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal: keys: kill task_struct->replacement_session_keyring keys: kill the dummy key_replace_session_keyring() keys: change keyctl_session_to_parent() to use task_work_add() genirq: reimplement exit_irq_thread() hook via task_work_add() task_work_add: generic process-context callbacks avr32: missed _TIF_NOTIFY_RESUME on one of do_notify_resume callers parisc: need to check NOTIFY_RESUME when exiting from syscall move key_repace_session_keyring() into tracehook_notify_resume() TIF_NOTIFY_RESUME is defined on all targets now
2012-05-31Merge branch 'for-3.5-take-2' of git://linux-nfs.org/~bfields/linuxLinus Torvalds
Pull nfsd update from Bruce Fields. * 'for-3.5-take-2' of git://linux-nfs.org/~bfields/linux: (23 commits) nfsd: trivial: use SEEK_SET instead of 0 in vfs_llseek SUNRPC: split upcall function to extract reusable parts nfsd: allocate id-to-name and name-to-id caches in per-net operations. nfsd: make name-to-id cache allocated per network namespace context nfsd: make id-to-name cache allocated per network namespace context nfsd: pass network context to idmap init/exit functions nfsd: allocate export and expkey caches in per-net operations. nfsd: make expkey cache allocated per network namespace context nfsd: make export cache allocated per network namespace context nfsd: pass pointer to export cache down to stack wherever possible. nfsd: pass network context to export caches init/shutdown routines Lockd: pass network namespace to creation and destruction routines NFSd: remove hard-coded dereferences to name-to-id and id-to-name caches nfsd: pass pointer to expkey cache down to stack wherever possible. nfsd: use hash table from cache detail in nfsd export seq ops nfsd: pass svc_export_cache pointer as private data to "exports" seq file ops nfsd: use exp_put() for svc_export_cache put nfsd: use cache detail pointer from svc_export structure on cache put nfsd: add link to owner cache detail to svc_export structure nfsd: use passed cache_detail pointer expkey_parse() ...
2012-05-31Merge branch 'akpm' (Andrew's patch-bomb)Linus Torvalds
Merge misc patches from Andrew Morton: - the "misc" tree - stuff from all over the map - checkpatch updates - fatfs - kmod changes - procfs - cpumask - UML - kexec - mqueue - rapidio - pidns - some checkpoint-restore feature work. Reluctantly. Most of it delayed a release. I'm still rather worried that we don't have a clear roadmap to completion for this work. * emailed from Andrew Morton <akpm@linux-foundation.org>: (78 patches) kconfig: update compression algorithm info c/r: prctl: add ability to set new mm_struct::exe_file c/r: prctl: extend PR_SET_MM to set up more mm_struct entries c/r: procfs: add arg_start/end, env_start/end and exit_code members to /proc/$pid/stat syscalls, x86: add __NR_kcmp syscall fs, proc: introduce /proc/<pid>/task/<tid>/children entry sysctl: make kernel.ns_last_pid control dependent on CHECKPOINT_RESTORE aio/vfs: cleanup of rw_copy_check_uvector() and compat_rw_copy_check_uvector() eventfd: change int to __u64 in eventfd_signal() fs/nls: add Apple NLS pidns: make killed children autoreap pidns: use task_active_pid_ns in do_notify_parent rapidio/tsi721: add DMA engine support rapidio: add DMA engine support for RIO data transfers ipc/mqueue: add rbtree node caching support tools/selftests: add mq_perf_tests ipc/mqueue: strengthen checks on mqueue creation ipc/mqueue: correct mq_attr_ok test ipc/mqueue: improve performance of send/recv selftests: add mq_open_tests ...
2012-05-31c/r: prctl: add ability to set new mm_struct::exe_fileCyrill Gorcunov
When we do restore we would like to have a way to setup a former mm_struct::exe_file so that /proc/pid/exe would point to the original executable file a process had at checkpoint time. For this the PR_SET_MM_EXE_FILE code is introduced. This option takes a file descriptor which will be set as a source for new /proc/$pid/exe symlink. Note it allows to change /proc/$pid/exe if there are no VM_EXECUTABLE vmas present for current process, simply because this feature is a special to C/R and mm::num_exe_file_vmas become meaningless after that. To minimize the amount of transition the /proc/pid/exe symlink might have, this feature is implemented in one-shot manner. Thus once changed the symlink can't be changed again. This should help sysadmins to monitor the symlinks over all process running in a system. In particular one could make a snapshot of processes and ring alarm if there unexpected changes of /proc/pid/exe's in a system. Note -- this feature is available iif CONFIG_CHECKPOINT_RESTORE is set and the caller must have CAP_SYS_RESOURCE capability granted, otherwise the request to change symlink will be rejected. Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Kees Cook <keescook@chromium.org> Cc: Tejun Heo <tj@kernel.org> Cc: Matt Helsley <matthltc@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-31c/r: prctl: extend PR_SET_MM to set up more mm_struct entriesCyrill Gorcunov
During checkpoint we dump whole process memory to a file and the dump includes process stack memory. But among stack data itself, the stack carries additional parameters such as command line arguments, environment data and auxiliary vector. So when we do restore procedure and once we've restored stack data itself we need to setup mm_struct::arg_start/end, env_start/end, so restored process would be able to find command line arguments and environment data it had at checkpoint time. The same applies to auxiliary vector. For this reason additional PR_SET_MM_(ARG_START | ARG_END | ENV_START | ENV_END | AUXV) codes are introduced. Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Acked-by: Kees Cook <keescook@chromium.org> Cc: Tejun Heo <tj@kernel.org> Cc: Andrew Vagin <avagin@openvz.org> Cc: Serge Hallyn <serge.hallyn@canonical.com> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Vasiliy Kulikov <segoon@openwall.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-31syscalls, x86: add __NR_kcmp syscallCyrill Gorcunov
While doing the checkpoint-restore in the user space one need to determine whether various kernel objects (like mm_struct-s of file_struct-s) are shared between tasks and restore this state. The 2nd step can be solved by using appropriate CLONE_ flags and the unshare syscall, while there's currently no ways for solving the 1st one. One of the ways for checking whether two tasks share e.g. mm_struct is to provide some mm_struct ID of a task to its proc file, but showing such info considered to be not that good for security reasons. Thus after some debates we end up in conclusion that using that named 'comparison' syscall might be the best candidate. So here is it -- __NR_kcmp. It takes up to 5 arguments - the pids of the two tasks (which characteristics should be compared), the comparison type and (in case of comparison of files) two file descriptors. Lookups for pids are done in the caller's PID namespace only. At moment only x86 is supported and tested. [akpm@linux-foundation.org: fix up selftests, warnings] [akpm@linux-foundation.org: include errno.h] [akpm@linux-foundation.org: tweak comment text] Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Pavel Emelyanov <xemul@parallels.com> Cc: Andrey Vagin <avagin@openvz.org> Cc: KOSAKI Motohiro <kosaki.motohiro@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Glauber Costa <glommer@parallels.com> Cc: Andi Kleen <andi@firstfloor.org> Cc: Tejun Heo <tj@kernel.org> Cc: Matt Helsley <matthltc@us.ibm.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: Vasiliy Kulikov <segoon@openwall.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: Valdis.Kletnieks@vt.edu Cc: Michal Marek <mmarek@suse.cz> Cc: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-31aio/vfs: cleanup of rw_copy_check_uvector() and compat_rw_copy_check_uvector()Christopher Yeoh
A cleanup of rw_copy_check_uvector and compat_rw_copy_check_uvector after changes made to support CMA in an earlier patch. Rather than having an additional check_access parameter to these functions, the first paramater type is overloaded to allow the caller to specify CHECK_IOVEC_ONLY which means check that the contents of the iovec are valid, but do not check the memory that they point to. This is used by process_vm_readv/writev where we need to validate that a iovec passed to the syscall is valid but do not want to check the memory that it points to at this point because it refers to an address space in another process. Signed-off-by: Chris Yeoh <yeohc@au1.ibm.com> Reviewed-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-31eventfd: change int to __u64 in eventfd_signal()Sha Zhengju
eventfd_ctx->count is an __u64 counter which is allowed to reach ULLONG_MAX. eventfd_write() adds a __u64 value to "count", but the kernel side eventfd_signal() only adds an int value to it. Make them consistent. [akpm@linux-foundation.org: update interface documentation] Signed-off-by: Sha Zhengju <handai.szj@taobao.com> Cc: Davide Libenzi <davidel@xmailserver.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-31rapidio: add DMA engine support for RIO data transfersAlexandre Bounine
Adds DMA Engine framework support into RapidIO subsystem. Uses DMA Engine DMA_SLAVE interface to generate data transfers to/from remote RapidIO target devices. Introduces RapidIO-specific wrapper for prep_slave_sg() interface with an extra parameter to pass target specific information. Uses scatterlist to describe local data buffer. Address flat data buffer on a remote side. Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com> Cc: Dan Williams <dan.j.williams@intel.com> Acked-by: Vinod Koul <vinod.koul@linux.intel.com> Cc: Li Yang <leoli@freescale.com> Cc: Matt Porter <mporter@kernel.crashing.org> Cc: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-31mqueue: separate mqueue default value from maximum valueKOSAKI Motohiro
Commit b231cca4381e ("message queues: increase range limits") changed mqueue default value when attr parameter is specified NULL from hard coded value to fs.mqueue.{msg,msgsize}_max sysctl value. This made large side effect. When user need to use two mqueue applications 1) using !NULL attr parameter and it require big message size and 2) using NULL attr parameter and only need small size message, app (1) require to raise fs.mqueue.msgsize_max and app (2) consume large memory size even though it doesn't need. Doug Ledford propsed to switch back it to static hard coded value. However it also has a compatibility problem. Some applications might started depend on the default value is tunable. The solution is to separate default value from maximum value. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Doug Ledford <dledford@redhat.com> Acked-by: Doug Ledford <dledford@redhat.com> Acked-by: Joe Korty <joe.korty@ccur.com> Cc: Amerigo Wang <amwang@redhat.com> Acked-by: Serge E. Hallyn <serue@us.ibm.com> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Manfred Spraul <manfred@colorfullife.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-31mqueue: revert bump up DFLT_*MAXKOSAKI Motohiro
Mqueue limitation is slightly naieve parameter likes other ipcs because unprivileged user can consume kernel memory by using ipcs. Thus, too aggressive raise bring us security issue. Example, current setting allow evil unprivileged user use 256GB (= 256 * 1024 * 1024*1024) and it's enough large to system will belome unresponsive. Don't do that. Instead, every admin should adjust the knobs for their own systems. Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: Doug Ledford <dledford@redhat.com> Acked-by: Joe Korty <joe.korty@ccur.com> Cc: Amerigo Wang <amwang@redhat.com> Acked-by: Serge E. Hallyn <serue@us.ibm.com> Cc: Jiri Slaby <jslaby@suse.cz> Cc: Manfred Spraul <manfred@colorfullife.com> Cc: Dave Hansen <haveblue@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-31ipc/mqueue: update maximums for the mqueue subsystemDoug Ledford
Commit b231cca4381e ("message queues: increase range limits") changed the maximum size of a message in a message queue from INT_MAX to 8192*128. Unfortunately, we had customers that relied on a size much larger than 8192*128 on their production systems. After reviewing POSIX, we found that it is silent on the maximum message size. We did find a couple other areas in which it was not silent. Fix up the mqueue maximums so that the customer's system can continue to work, and document both the POSIX and real world requirements in ipc_namespace.h so that we don't have this issue crop back up. Also, commit 9cf18e1dd74cd0 ("ipc: HARD_MSGMAX should be higher not lower on 64bit") fiddled with HARD_MSGMAX without realizing that the number was intentionally in place to limit the msg queue depth to one that was small enough to kmalloc an array of pointers (hence why we divided 128k by sizeof(long)). If we wish to meet POSIX requirements, we have no choice but to change our allocation to a vmalloc instead (at least for the large queue size case). With that, it's possible to increase our allowed maximum to the POSIX requirements (or more if we choose). [sfr@canb.auug.org.au: using vmalloc requires including vmalloc.h] Signed-off-by: Doug Ledford <dledford@redhat.com> Cc: Serge E. Hallyn <serue@us.ibm.com> Cc: Amerigo Wang <amwang@redhat.com> Cc: Joe Korty <joe.korty@ccur.com> Cc: Jiri Slaby <jslaby@suse.cz> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Manfred Spraul <manfred@colorfullife.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-31ipc/mqueue: switch back to using non-max values on createDoug Ledford
Commit b231cca4381e ("message queues: increase range limits") changed how we create a queue that does not include an attr struct passed to open so that it creates the queue with whatever the maximum values are. However, if the admin has set the maximums to allow flexibility in creating a queue (aka, both a large size and large queue are allowed, but combined they create a queue too large for the RLIMIT_MSGQUEUE of the user), then attempts to create a queue without an attr struct will fail. Switch back to using acceptable defaults regardless of what the maximums are. Note: so far, we only know of a few applications that rely on this behavior (specifically, set the maximums in /proc, then run the application which calls mq_open() without passing in an attr struct, and the application expects the newly created message queue to have the maximum sizes that were set in /proc used on the mq_open() call, and all of those applications that we know of are actually part of regression test suites that were coded to do something like this: for size in 4096 65536 $((1024 * 1024)) $((16 * 1024 * 1024)); do echo $size > /proc/sys/fs/mqueue/msgsize_max mq_open || echo "Error opening mq with size $size" done These test suites that depend on any behavior like this are broken. The concept that programs should rely upon the system wide maximum in order to get their desired results instead of simply using a attr struct to specify what they want is fundamentally unfriendly programming practice for any multi-tasking OS. Fixing this will break those few apps that we know of (and those app authors recognize the brokenness of their code and the need to fix it). However, the following patch "mqueue: separate mqueue default value" allows a workaround in the form of new knobs for the default msg queue creation parameters for any software out there that we don't already know about that might rely on this behavior at the moment. Signed-off-by: Doug Ledford <dledford@redhat.com> Cc: Serge E. Hallyn <serue@us.ibm.com> Cc: Amerigo Wang <amwang@redhat.com> Cc: Joe Korty <joe.korty@ccur.com> Cc: Jiri Slaby <jslaby@suse.cz> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Manfred Spraul <manfred@colorfullife.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-31ipc/mqueue: cleanup definition names and locationsDoug Ledford
Since commit b231cca4381e ("message queues: increase range limits") on Oct 18, 2008, calls to mq_open() that did not pass in an attribute struct and expected to get default values for the size of the queue and the max message size now get the system wide maximums instead of hardwired defaults like they used to get. This was uncovered when one of the earlier patches in this patch set increased the default system wide maximums at the same time it increased the hard ceiling on the system wide maximums (a customer specifically needed the hard ceiling brought back up, the new ceiling that commit b231cca4381e introduced was too low for their production systems). By increasing the default maximums and not realising they were tied to any attempt to create a message queue without an attribute struct, I had inadvertently made it such that all message queue creation attempts without an attribute struct were failing because the new default maximums would create a queue that exceeded the default rlimit for message queue bytes. As a result, the system wide defaults were brought back down to their previous levels, and the system wide ceilings on the maximums were raised to meet the customer's needs. However, the fact that the no attribute struct behavior of mq_open() could be broken by changing the system wide maximums for message queues was seen as fundamentally broken itself. So we hardwired the no attribute case back like it used to be. But, then we realized that on the very off chance that some piece of software in the wild depended on that behavior, we could work around that issue by adding two new knobs to /proc that allowed setting the defaults for message queues created without an attr struct separately from the system wide maximums. What is not an option IMO is to leave the current behavior in place. No piece of software should ever rely on setting the system wide maximums in order to get a desired message queue. Such a reliance would be so fundamentally multitasking OS unfriendly as to not really be tolerable. Fortunately, we don't know of any software in the wild that uses this except for a regression test program that caught the issue in the first place. If there is though, we have made accommodations with the two new /proc knobs (and that's all the accommodations such fundamentally broken software can be allowed).. This patch: The various defines for minimums and maximums of the sysctl controllable mqueue values are scattered amongst different files and named inconsistently. Move them all into ipc_namespace.h and make them have consistent names. Additionally, make the number of queues per namespace also have a minimum and maximum and use the same sysctl function as the other two settable variables. Signed-off-by: Doug Ledford <dledford@redhat.com> Acked-by: Serge E. Hallyn <serue@us.ibm.com> Cc: Amerigo Wang <amwang@redhat.com> Cc: Joe Korty <joe.korty@ccur.com> Cc: Jiri Slaby <jslaby@suse.cz> Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Manfred Spraul <manfred@colorfullife.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-31kexec: export kexec.h to user spacemaximilian attems
Add userspace definitions, guard all relevant kernel structures. While at it document stuff and remove now useless userspace hint. It is easy to add the relevant system call to respective libc's, but it seems pointless to have to duplicate the data structures. This is based on the kexec-tools headers, with the exception of just using int on return (succes or failure) and using size_t instead of 'unsigned long int' for the number of segments argument of kexec_load(). Signed-off-by: maximilian attems <max@stro.at> Cc: Simon Horman <horms@verge.net.au> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Haren Myneni <hbabu@us.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-31cpu: introduce clear_tasks_mm_cpumask() helperAnton Vorontsov
Many architectures clear tasks' mm_cpumask like this: read_lock(&tasklist_lock); for_each_process(p) { if (p->mm) cpumask_clear_cpu(cpu, mm_cpumask(p->mm)); } read_unlock(&tasklist_lock); Depending on the context, the code above may have several problems, such as: 1. Working with task->mm w/o getting mm or grabing the task lock is dangerous as ->mm might disappear (exit_mm() assigns NULL under task_lock(), so tasklist lock is not enough). 2. Checking for process->mm is not enough because process' main thread may exit or detach its mm via use_mm(), but other threads may still have a valid mm. This patch implements a small helper function that does things correctly, i.e.: 1. We take the task's lock while whe handle its mm (we can't use get_task_mm()/mmput() pair as mmput() might sleep); 2. To catch exited main thread case, we use find_lock_task_mm(), which walks up all threads and returns an appropriate task (with task lock held). Also, Per Peter Zijlstra's idea, now we don't grab tasklist_lock in the new helper, instead we take the rcu read lock. We can do this because the function is called after the cpu is taken down and marked offline, so no new tasks will get this cpu set in their mm mask. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Cc: Richard Weinberger <richard@nod.at> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Mike Frysinger <vapier@gentoo.org> Cc: Paul Mundt <lethal@linux-sh.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-05-31cred: remove task_is_dead() from __task_cred() validationOleg Nesterov
Commit 8f92054e7ca1 ("CRED: Fix __task_cred()'s lockdep check and banner comment"): add the following validation condition: task->exit_state >= 0 to permit the access if the target task is dead and therefore unable to change its own credentials. OK, but afaics currently this can only help wait_task_zombie() which calls __task_cred() without rcu lock. Remove this validation and change wait_task_zombie() to use task_uid() instead. This means we do rcu_read_lock() only to shut up the lockdep, but we already do the same in, say, wait_task_stopped(). task_is_dead() should die, task->exit_state != 0 means that this task has passed exit_notify(), only do_wait-like code paths should use this. Unfortunately, we can't kill task_is_dead() right now, it has already acquired buggy users in drivers/staging. The fix already exists. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com> Acked-by: David Howells <dhowells@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>