summaryrefslogtreecommitdiff
AgeCommit message (Collapse)Author
2011-04-28ARM: kprobes: Fix probing of conditionally executed instructionsJon Medhurst
When a kprobe is placed onto conditionally executed ARM instructions, many of the emulation routines used to single step them produce corrupt register results. Rather than fix all of these cases we modify the framework which calls them to test the relevant condition flags and, if the test fails, skip calling the emulation code. Signed-off-by: Jon Medhurst <tixy@yxit.co.uk> Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-28kprobes/arm: Fix ldrd/strd emulationViktor Rosendahl
Currently emulate_ldrd and emulate_strd don't even have the adjustment of the PC value, so in case of Rn == PC, it will not update the PC incorrectly but instead load/store from the wrong address. Let's add both the adjustment of the PC value and the check for PC == PC. Signed-off-by: Viktor Rosendahl <viktor.rosendahl@nokia.com> Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
2011-04-05Linux 2.6.39-rc2Linus Torvalds
2011-04-05Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-2.6-block * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-2.6-block: ide: always ensure that blk_delay_queue() is called if we have pending IO block: fix request sorting at unplug dm: improve block integrity support fs: export empty_aops ide: ide_requeue_and_plug() reinstate "always plug" behaviour blk-throttle: don't call xchg on bool ufs: remove unessecary blk_flush_plug block: make the flush insertion use the tail of the dispatch list block: get rid of elv_insert() interface block: dump request state on seeing a corrupted request completion
2011-04-05inotify: fix double free/corruption of stuct userEric Paris
On an error path in inotify_init1 a normal user can trigger a double free of struct user. This is a regression introduced by a2ae4cc9a16e ("inotify: stop kernel memory leak on file creation failure"). We fix this by making sure that if a group exists the user reference is dropped when the group is cleaned up. We should not explictly drop the reference on error and also drop the reference when the group is cleaned up. The new lifetime rules are that an inotify group lives from inotify_new_group to the last fsnotify_put_group. Since the struct user and inotify_devs are directly tied to this lifetime they are only changed/updated in those two locations. We get rid of all special casing of struct user or user->inotify_devs. Signed-off-by: Eric Paris <eparis@redhat.com> Cc: stable@kernel.org (2.6.37 and up) Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-04-05ide: always ensure that blk_delay_queue() is called if we have pending IOJens Axboe
Just because we are not requeuing a request does not mean that some aren't pending. So always issue a blk_delay_queue() if either we are requeueing OR there's pending IO. This fixes a boot problem for some IDE boxes. Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-04-05block: fix request sorting at unplugKonstantin Khlebnikov
Comparison function for list_sort() must be anticommutative, otherwise it is not sorting in ordinary meaning. But fortunately list_sort() always check ((*cmp)(priv, a, b) <= 0) it not distinguish negative and zero, so comparison function can implement only less-or-equal instead of full three-way comparison. Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-04-05dm: improve block integrity supportMike Snitzer
The current block integrity (DIF/DIX) support in DM is verifying that all devices' integrity profiles match during DM device resume (which is past the point of no return). To some degree that is unavoidable (stacked DM devices force this late checking). But for most DM devices (which aren't stacking on other DM devices) the ideal time to verify all integrity profiles match is during table load. Introduce the notion of an "initialized" integrity profile: a profile that was blk_integrity_register()'d with a non-NULL 'blk_integrity' template. Add blk_integrity_is_initialized() to allow checking if a profile was initialized. Update DM integrity support to: - check all devices with _initialized_ integrity profiles match during table load; uninitialized profiles (e.g. for underlying DM device(s) of a stacked DM device) are ignored. - disallow a table load that would result in an integrity profile that conflicts with a DM device's existing (in-use) integrity profile - avoid clearing an existing integrity profile - validate all integrity profiles match during resume; but if they don't all we can do is report the mismatch (during resume we're past the point of no return) Signed-off-by: Mike Snitzer <snitzer@redhat.com> Cc: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-04-05fs: export empty_aopsJens Axboe
With the ->sync_page() hook gone, we have a few users that add their own static address_space_operations without any functions defined. fs/inode.c already has an empty_aops that it uses for init purposes. Lets export that and use it in the places where an otherwise empty aops was defined. Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-04-05ide: ide_requeue_and_plug() reinstate "always plug" behaviourJens Axboe
We see stalls if we don't always ensure that the queue gets run again. Even if rq == NULL, we could have other pending requests in the queue. Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-04-05blk-throttle: don't call xchg on boolAndreas Schwab
xchg does not work portably with smaller than 32bit types. Signed-off-by: Andreas Schwab <schwab@linux-m68k.org> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-04-05ufs: remove unessecary blk_flush_plugChristoph Hellwig
We already flush the per-process plugging list when context switching, so a blk_flush_plug call just before a yield() is not needed. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-04-05block: make the flush insertion use the tail of the dispatch listJens Axboe
It's not a preempt type request, in fact we have to insert it behind requests that do specify INSERT_FRONT. Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-04-05block: get rid of elv_insert() interfaceJens Axboe
Merge it with __elv_add_request(), it's pretty pointless to have a function with only two callers. The main interface is elv_add_request()/__elv_add_request(). Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-04-05block: dump request state on seeing a corrupted request completionJens Axboe
Currently we just dump a non-informative 'request botched' message. Lets actually try and print something sane to help debug issues around this. Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2011-04-05Merge branch 'drm-intel-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/keithp/linux-2.6 * 'drm-intel-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/keithp/linux-2.6: drm/i915/lvds: Remove 0xa0 DDC probe for LVDS drm/i915/crt: Remove 0xa0 probe for VGA
2011-04-05Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: Input: rpckbd - fix a leak of the IRQ during init failure Input: wacom - add support for Lenovo tablet ID (0xE6) Input: i8042 - downgrade selftest error message to dbg() Input: synaptics - fix crash in synaptics_module_init() Input: spear-keyboard - fix inverted condition in interrupt handler Input: uinput - allow for 0/0 min/max on absolute axes. Input: sparse-keymap - report KEY_UNKNOWN for unknown scan codes Input: sparse-keymap - report scancodes with key events Input: h3600_ts_input - fix a spelling error Input: wacom - report resolution for pen devices Input: wacom - constify wacom_features for a new missed Bamboo models
2011-04-05Merge branch 'merge' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc * 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: powerpc/pseries: Fix build without CONFIG_HOTPLUG_CPU powerpc: Set nr_cpu_ids early and use it to free PACAs powerpc/pseries: Don't register global initcall powerpc/kexec: Fix mismatched ifdefs for PPC64/SMP. edac/mpc85xx: Limit setting/clearing of HID1[RFXE] to e500v1/v2 cores powerpc/85xx: Update dts for PCIe memory maps to match u-boot of Px020RDB
2011-04-05Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: Btrfs: don't warn in btrfs_add_orphan Btrfs: fix free space cache when there are pinned extents and clusters V2 Btrfs: Fix uninitialized root flags for subvolumes btrfs: clear __GFP_FS flag in the space cache inode Btrfs: fix memory leak in start_transaction() Btrfs: fix memory leak in btrfs_ioctl_start_sync() Btrfs: fix subvol_sem leak in btrfs_rename() Btrfs: Fix oops for defrag with compression turned on Btrfs: fix /proc/mounts info. Btrfs: fix compiler warning in file.c
2011-04-05Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6Linus Torvalds
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (27 commits) ipv6: Don't pass invalid dst_entry pointer to dst_release(). mlx4: fix kfree on error path in new_steering_entry() tcp: len check is unnecessarily devastating, change to WARN_ON sctp: malloc enough room for asconf-ack chunk sctp: fix auth_hmacs field's length of struct sctp_cookie net: Fix dev dev_ethtool_get_rx_csum() for forced NETIF_F_RXCSUM usbnet: use eth%d name for known ethernet devices starfire: clean up dma_addr_t size test iwlegacy: fix bugs in change_interface carl9170: Fix tx aggregation problems with some clients iwl3945: disable hw scan by default wireless: rt2x00: rt2800usb.c add and identify ids iwl3945: do not deprecate software scan mac80211: fix aggregation frame release during timeout cfg80211: fix BSS double-unlinking (continued) cfg80211:: fix possible NULL pointer dereference mac80211: fix possible NULL pointer dereference mac80211: fix NULL pointer dereference in ieee80211_key_alloc() ath9k: fix a chip wakeup related crash in ath9k_start mac80211: fix a crash in minstrel_ht in HT mode with no supported MCS rates ...
2011-04-05drm/i915/lvds: Remove 0xa0 DDC probe for LVDSChris Wilson
This is a revert of 428d2e828c0a68206e5158a42451487601dc9194. This is broken in the same manner as for VGA: trying to write to an invalid address on the (currently 7-bit) i2c bus. One notable failure appears to be for MacBooks. The scary part was that it gave the appearance of working (i.e. reporting the absence of the panel) on various all-in-one machines with ghost LVDS panels and not failing for laptops. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Acked-by: Dave Airlie <airlied@linux.ie> Signed-off-by: Keith Packard <keithp@keithp.com>
2011-04-05drm/i915/crt: Remove 0xa0 probe for VGAChris Wilson
This is a moral revert of 6ec3d0c0e9c0c605696e91048eebaca7b0c36695. Following the fix to reset the GMBUS controller after a NAK, we finally utilize the 0xa0 probe for a CRT connection. And discover that the code is broken. Shock. There are a number of issues, but following a key insight from Dave Airlie, that 0xA0 is an invalid address on a 7-bit bus (though not if we were to enable 10-bit addressing), and would look like the EDID port 0x50, it is possible to see where the confusion starts. In short, a write to 0xA0 is accepted by the GMBUS controller which we interpreted as meaning the existence of a connection (a slave on the other end of the wire ACKing the write). That was false. During testing with a broken GMBUS implementation, which never reset an earlier NAK, this test always reported a NAK and so we proceeded on to the next test. Reported-and-tested-by: Sitsofe Wheeler <sitsofe@yahoo.com> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=35904 Reported-and-tested-by: Riccardo Magliocchetti <riccardo.magliocchetti@gmail.com> Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=32612 Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Acked-by: Dave Airlie <airlied@linux.ie> Signed-off-by: Keith Packard <keithp@keithp.com>
2011-04-05powerpc/pseries: Fix build without CONFIG_HOTPLUG_CPUMatt Evans
Signed-off-by: Matt Evans <matt@ozlabs.au.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-04-05powerpc: Set nr_cpu_ids early and use it to free PACAsRyan Grimm
Without this, "holes" in the CPU numbering can cause us to free too many PACAs Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-04-05powerpc/pseries: Don't register global initcallBenjamin Herrenschmidt
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-04-05powerpc/kexec: Fix mismatched ifdefs for PPC64/SMP.Paul Gortmaker
Commit b3df895aebe091b1657 "powerpc/kexec: Add support for FSL-BookE" introduced the original PPC_STD_MMU_64 checks around the function crash_kexec_wait_realmode(). Then commit c2be05481f61252 "powerpc: Fix default_machine_crash_shutdown #ifdef botch" changed the ifdef around the calling site to add a check on SMP, but the ifdef around the function itself was left unchanged, leaving an unused function for PPC_STD_MMU_64=y and SMP=n Rather than have two ifdefs that can get out of sync like this, simply put the corrected conditional around the function and use a stub to get rid of one set of ifdefs completely. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2011-04-05Merge remote branch 'kumar/merge' into mergeBenjamin Herrenschmidt
2011-04-05Btrfs: don't warn in btrfs_add_orphanJosef Bacik
When I moved the orphan adding to btrfs_truncate I missed the fact that during orphan cleanup we just add the orphan items to the orphan list without going through btrfs_orphan_add, which results in lots of warnings on mount if you have any orphan items that need to be truncated. Just remove this warning since it's ok, this will allow all of the normal space accounting take place. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-04-05Btrfs: fix free space cache when there are pinned extents and clusters V2Josef Bacik
I noticed a huge problem with the free space cache that was presenting as an early ENOSPC. Turns out when writing the free space cache out I forgot to take into account pinned extents and more importantly clusters. This would result in us leaking free space everytime we unmounted the filesystem and remounted it. I fix this by making sure to check and see if the current block group has a cluster and writing out any entries that are in the cluster to the cache, as well as writing any pinned extents we currently have to the cache since those will be available for us to use the next time the fs mounts. This patch also adds a check to the end of load_free_space_cache to make sure we got the right amount of free space cache, and if not make sure to clear the cache and re-cache the old fashioned way. Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-04-05Btrfs: Fix uninitialized root flags for subvolumesLi Zefan
root_item->flags and root_item->byte_limit are not initialized when a subvolume is created. This bug is not revealed until we added readonly snapshot support - now you mount a btrfs filesystem and you may find the subvolumes in it are readonly. To work around this problem, we steal a bit from root_item->inode_item->flags, and use it to indicate if those fields have been properly initialized. When we read a tree root from disk, we check if the bit is set, and if not we'll set the flag and initialize the two fields of the root item. Reported-by: Andreas Philipp <philipp.andreas@gmail.com> Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Tested-by: Andreas Philipp <philipp.andreas@gmail.com> cc: stable@kernel.org Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-04-05btrfs: clear __GFP_FS flag in the space cache inodeMiao Xie
the object id of the space cache inode's key is allocated from the relative root, just like the regular file. So we can't identify space cache inode by checking the object id of the inode's key, and we have to clear __GFP_FS flag at the time we look up the space cache inode. Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Liu Bo <liubo2009@cn.fujitsu.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-04-05Btrfs: fix memory leak in start_transaction()Yoshinori Sano
Free btrfs_trans_handle when join_transaction() fails in start_transaction() Signed-off-by: Yoshinori Sano <yoshinori.sano@gmail.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-04-05Btrfs: fix memory leak in btrfs_ioctl_start_sync()Tsutomu Itoh
Call btrfs_end_transaction() if btrfs_commit_transaction_async() fails. Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-04-05Btrfs: fix subvol_sem leak in btrfs_rename()Johann Lombardi
btrfs_rename() does not release the subvol_sem if the transaction failed to start. Signed-off-by: Johann Lombardi <johann@whamcloud.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-04-05Btrfs: Fix oops for defrag with compression turned onLi Zefan
When we defrag a file, whose size can be fit into an inline extent, with compression enabled, the compress type is set to be fs_info->compress_type, which is 0 if the btrfs filesystem is mounted without compress option. This leads to oops. Reported-by: Daniel Blueman <daniel.blueman@gmail.com> Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-04-05Btrfs: fix /proc/mounts info.Tsutomu Itoh
Some mount options are not displayed by /proc/mounts. This patch displays the option such as compress_type by /proc/mounts. Ex. [before] $ mount | grep sdc2 /dev/sdc2 on /test12 type btrfs (rw,space_cache,compress=lzo) $ cat /proc/mounts | grep sdc2 /dev/sdc2 /test12 btrfs rw,relatime,compress 0 0 [after] $ mount | grep sdc2 /dev/sdc2 on /test12 type btrfs (rw,space_cache,compress=lzo) $ cat /proc/mounts | grep sdc2 /dev/sdc2 /test12 btrfs rw,relatime,compress=lzo,space_cache 0 0 Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-04-05Btrfs: fix compiler warning in file.cTsutomu Itoh
While compiling Btrfs, I got following messages: CC [M] fs/btrfs/file.o fs/btrfs/file.c: In function '__btrfs_buffered_write': fs/btrfs/file.c:909: warning: 'ret' may be used uninitialized in this function CC [M] fs/btrfs/tree-defrag.o This patch fixes compiler warning. Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-04-04Merge branch 'drm-fixes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6 * 'drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6: drm: fix "persistant" typo drm/radeon/kms: add some new ontario pci ids drm/radeon/kms: pageflipping cleanup for avivo+ drm/radeon/kms: Add support for tv-out dongle on G5 9600 drm: export drm_find_cea_extension to drivers drm/radeon/kms: add some sanity checks to obj info record parsingi (v2) drm/i915: Reset GMBUS controller after NAK drm/i915: Busy-spin wait_for condition in atomic contexts drm/i915/lvds: Always return connected in the absence of better information
2011-04-04Merge branch 'next' of git://git.monstr.eu/linux-2.6-microblazeLinus Torvalds
* 'next' of git://git.monstr.eu/linux-2.6-microblaze: microblaze: Fix ftrace microblaze: Wire up new syscalls microblaze: Fix level/edge irq sensibility
2011-04-04Documentation: update cgroups info user groups namesGeunsik Lim
Update suitable words to explain / understand cgroups contents. Signed-off-by: Geunsik Lim <geunsik.lim@samsung.com> Cc: Paul Menage <menage@google.com> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-04-04Documentation: consolidate leds files to leds/ subdirAntonio Ospite
leds: move leds-class documentation under the leds/ subdir. Add also a leds/00-INDEX file describing the files under leds/ Signed-off-by: Antonio Ospite <ospite@studenti.unina.it> Acked-by: Richard Purdie <richard.purdie@linuxfoundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-04-04kemleak-test: build as module onlyDaniel Baluta
mm/kmemleak-test.c is used to provide an example of how kmemleak tool works. Memory is leaked at module unload-time, so building the test in kernel (Y) makes the leaks impossible and the test useless. Qualify DEBUG_KMEMLEAK_TEST config symbol with "depends on m", to restrict module-only building. Signed-off-by: Daniel Baluta <dbaluta@ixiacom.com> Acked-by: Pekka Enberg <penberg@kernel.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-04-04Documentation: fix minor typos/spellingSylvestre Ledru
Fix some minor typos: * informations => information * there own => their own * these => this Signed-off-by: Sylvestre Ledru <sylvestre.ledru@scilab.org> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-04-04Documentation: update panic parameter infoRandy Dunlap
Add a little more info for some of the panic-related kernel parameters. Fix "oops=panic" to fit in 80 columns. Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Reviewed-by: Jesper Juhl <jj@chaosbits.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-04-04kernel/signal.c: add kernel-doc notation to syscallsRandy Dunlap
Add kernel-doc to syscalls in signal.c. Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-04-04kernel/signal.c: fix typos and coding styleRandy Dunlap
General coding style and comment fixes; no code changes: - Use multi-line-comment coding style. - Put some function signatures completely on one line. - Hyphenate some words. - Spell Posix as POSIX. - Correct typos & spellos in some comments. - Drop trailing whitespace. - End sentences with periods. Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-04-04Documentation: update kmemleak arch. infoDaniel Baluta
Besides x86 and arm, kmemleak now supports powerpc, sparc, sh, microblaze and tile. Signed-off-by: Daniel Baluta <dbaluta@ixiacom.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-04-05drm: fix "persistant" typoJan Engelhardt
Signed-off-by: Jan Engelhardt <jengelh@medozas.de> Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-04-05drm/radeon/kms: add some new ontario pci idsAlex Deucher
Signed-off-by: Alex Deucher <alexdeucher@gmail.com> Cc:stable@kernel.org Signed-off-by: Dave Airlie <airlied@redhat.com>
2011-04-04tty: fix endless work loop when the buffer fills upLinus Torvalds
Commit f23eb2b2b285 ('tty: stop using "delayed_work" in the tty layer') ended up causing hung machines on UP with no preemption, because the work routine to flip the buffer data to the ldisc would endlessly re-arm itself if the destination buffer had filled up. With the delayed work, that only caused a timer-driving polling of the tty state every timer tick, but without the delay we just ended up with basically a busy loop instead. Stop the insane polling, and instead make the code that opens up the receive room re-schedule the buffer flip work. That's what we should have been doing anyway. This same "poll for tty room" issue is almost certainly also the cause of excessive kworker activity when idle reported by Dave Jones, who also reported "flush_to_ldisc executing 2500 times a second" back in Nov 2010: http://lkml.org/lkml/2010/11/30/592 which is that silly flushing done every timer tick. Wasting both power and CPU for no good reason. Reported-and-tested-by: Alexander Beregalov <a.beregalov@gmail.com> Reported-and-tested-by: Sitsofe Wheeler <sitsofe@yahoo.com> Cc: Greg KH <gregkh@suse.de> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Dave Jones <davej@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-15 21:54:40 +0000