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2009-03-26Merge branch 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6Linus Torvalds
* 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6: (81 commits) [S390] remove duplicated #includes [S390] cpumask: use mm_cpumask() wrapper [S390] cpumask: Use accessors code. [S390] cpumask: prepare for iterators to only go to nr_cpu_ids/nr_cpumask_bits. [S390] cpumask: remove cpu_coregroup_map [S390] fix clock comparator save area usage [S390] Add hwcap flag for the etf3 enhancement facility [S390] Ensure that ipl panic notifier is called late. [S390] fix dfp elf hwcap/facility bit detection [S390] smp: perform initial cpu reset before starting a cpu [S390] smp: fix memory leak on __cpu_up [S390] ipl: Improve checking logic and remove switch defaults. [S390] s390dbf: Remove needless check for NULL pointer. [S390] s390dbf: Remove redundant initilizations. [S390] use kzfree() [S390] BUG to BUG_ON changes [S390] zfcpdump: Prevent zcore from beeing built as a kernel module. [S390] Use csum_partial in checksum.h [S390] cleanup lowcore.h [S390] eliminate ipl_device from lowcore ...
2009-03-26Merge branch 'master' of /home/davem/src/GIT/linux-2.6/David S. Miller
Conflicts: drivers/net/wimax/i2400m/usb-notif.c
2009-03-26[S390] use kzfree()Johannes Weiner
Use kzfree() instead of memset() + kfree(). Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] BUG to BUG_ON changesStoyan Gaydarov
Signed-off-by: Stoyan Gaydarov <stoyboyker@gmail.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] Use csum_partial in checksum.hFrank Munzert
The cksm function in system.h is duplicate to csum_partial in checksum.h. Remove cksm and use csum_partial instead. Signed-off-by: Frank Munzert <munzert@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] eliminate cpuinfo_S390 structureMartin Schwidefsky
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] list usage cleanup in s390Eric Sesterhenn
Trivial cleanup, list_del(); list_add{,_tail}() is equivalent to list_move{,_tail}(). Semantic patch for coccinelle can be found at www.cccmz.de/~snakebyte/list_move_tail.spatch Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] tape message cleanupCarsten Otte
This is a cleanup of all the messages this driver prints. It uses the dev_message macros now. Signed-off-by: Carsten Otte <cotte@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] qdio: merge inbound and outbound handler functionsJan Glauber
The inbound and outbound handlers are nearly identical if the outbound handler uses first_to_check as end index instead of last_move. Since both values are identical at that point the handlers can be merged. Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] qdio: report SIGA errors directlyJan Glauber
Errors from SIGA instructions are stored in the per queue qdio_error and reported back when the queue handler is called. That opens a race when multiple error conditions occur simultanously. Report SIGA errors immediately in the return value of do_QDIO so the upper layer can react and SIGA errors no longer interfere with other errors. Move the SIGA error handling in qeth from the outbound handler to qeth_flush_buffers. Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
2009-03-26[S390] qdio: tasklet termination in case of module unloadJan Glauber
If the qdio module is unloaded the tiqdio tasklet must be terminated by tasklet_kill. Move the tasklet_kill after the unregistration of the adapter interrupt so the tiqdio tasklet will not be scheduled anymore before calling tasklet_kill. Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] qdio: seperate last move index and polling indexJan Glauber
The index value that indicated that the input queue moved was also used to store the index of the first acknowledged buffer. For non-qebsm only the newest buffer is acknowledged which may be different from the last move index so two seperate values are needed to track the input queue. Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] qdio: move ACK to newest buffer for devices without QEBSMJan Glauber
The ACKnowledgement state should be set on the newest SBAL so an adapter interrupt surpression check needs to scan fewer SBALs. Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] qdio: call qdio_free also if qdio_shutdown failsJan Glauber
qdio_cleanup is a wrapper function that should call qdio_shutdown and qdio_free. qdio_free was not called if an error occured in qdio_shutdown resulting in a missing free of allocated resources. Call qdio_free regardless of the return value of qdio_shutdown. Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] qdio: proper kill of qdio taskletsJan Glauber
The queue tasklets were stopped with tasklet_disable. Although tasklet_disable prevents the tasklet from beeing executed it is still possible that a tasklet is scheduled on a CPU at that point. A following qdio_establish calls tasklet_init which clears the tasklet count and the tasklet state leading to the following Oops: <2>kernel BUG at kernel/softirq.c:392! <4>illegal operation: 0001 [#1] SMP <4>Modules linked in: iptable_filter ip_tables x_tables dm_round_robin dm_multipath scsi_dh sg sd_mod crc_t10dif nfs lockd nfs _acl sunrpc fuse loop dm_mod qeth_l3 ipv6 zfcp qeth scsi_transport_fc qdio scsi_tgt scsi_mod chsc_sch ccwgroup dasd_eckd_mod dasdm od ext3 mbcache jbd <4>Supported: Yes <4>CPU: 0 Not tainted 2.6.27.13-1.1.mz13-default #1 <4>Process blast.LzS_64 (pid: 16445, task: 000000006cc02538, ksp: 000000006cb67998) <4>Krnl PSW : 0704c00180000000 00000000001399f4 (tasklet_action+0xc8/0x1d4) <4> R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:0 PM:0 EA:3 <4>Krnl GPRS: ffffffff00000030 0000000000000002 0000000000000002 fffffffffffffffe <4> 000000000013aabe 00000000003b6a18 fffffffffffffffd 0000000000000000 <4> 00000000006705a8 000000007d0914a8 000000007d0914b0 000000007fecfd30 <4> 0000000000000000 00000000003b63e8 000000007fecfd90 000000007fecfd30 <4>Krnl Code: 00000000001399e8: b9200021 cgr %r2,%r1 <4> 00000000001399ec: a7740004 brc 7,1399f4 <4> 00000000001399f0: a7f40001 brc 15,1399f2 <4> >00000000001399f4: c0100027e8ee larl %r1,636bd0 <4> 00000000001399fa: bf1f1008 icm %r1,15,8(%r1) <4> 00000000001399fe: a7840019 brc 8,139a30 <4> 0000000000139a02: c0300027e8ef larl %r3,636be0 <4> 0000000000139a08: e3c030000004 lg %r12,0(%r3) <4>Call Trace: <4>([<0000000000139c12>] tasklet_hi_action+0x112/0x1d4) <4> [<000000000013aabe>] __do_softirq+0xde/0x1c4 <4> [<000000000010fa2e>] do_softirq+0x96/0xb0 <4> [<000000000013a8d8>] irq_exit+0x70/0xcc <4> [<000000000010d1d8>] do_extint+0xf0/0x110 <4> [<0000000000113b10>] ext_no_vtime+0x16/0x1a <4> [<000003e0000a3662>] ext3_dirty_inode+0xe6/0xe8 [ext3] <4>([<00000000001f6cf2>] __mark_inode_dirty+0x52/0x1d4) <4> [<000003e0000a44f0>] ext3_ordered_write_end+0x138/0x190 [ext3] <4> [<000000000018d5ec>] generic_perform_write+0x174/0x230 <4> [<0000000000190144>] generic_file_buffered_write+0xb4/0x194 <4> [<0000000000190864>] __generic_file_aio_write_nolock+0x418/0x454 <4> [<0000000000190ee2>] generic_file_aio_write+0x76/0xe4 <4> [<000003e0000a05c2>] ext3_file_write+0x3e/0xc8 [ext3] <4> [<00000000001cc2fe>] do_sync_write+0xd6/0x120 <4> [<00000000001ccfc8>] vfs_write+0xac/0x184 <4> [<00000000001cd218>] SyS_write+0x68/0xe0 <4> [<0000000000113402>] sysc_noemu+0x10/0x16 <4> [<0000020000043188>] 0x20000043188 <4>Last Breaking-Event-Address: <4> [<00000000001399f0>] tasklet_action+0xc4/0x1d4 <6>qdio: 0.0.c61b ZFCP on SC f67 using AI:1 QEBSM:0 PCI:1 TDD:1 SIGA: W AOP <4> <0>Kernel panic - not syncing: Fatal exception in interrupt Use tasklet_kill instead of tasklet_disbale. Since tasklet_schedule must not be called after tasklet_kill use the QDIO_IRQ_STATE_STOPPED to inidicate that a queue is going down and prevent further tasklet schedules in that case. Remove superflous tasklet_schedule from input queue setup, at that time the queues are not ready so the schedule results in a NOP. Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] qdio: Dont call qdio_shutdown in case qdio_activate failsJan Glauber
Remove the call to qdio_shutdown from qdio_activate since the upper-layer drivers are responsible to call qdio_shutdown when qdio_activate returns with an error. Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] qdio: add missing tiq_list lockingJan Glauber
Add a mutex to protect the tiq_list. Although reading the list is done using RCU adding and removing elements from the list must still happen locked since multiple qdio devices may change the list in parallel otherwise. Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio: prevent workqueue deadlockPeter Oberparleiter
Subchannel reprobing can block the kslowcrw workqueue indefinitely while waiting for device recognition to finish which is also scheduled to run on kslowcrw. Prevent this deadlock by moving the waiting portion of subchannel reprobing to the cio workqueue. Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio: remove unused local variableSebastian Ott
Remove unused subchannel pointer in io_subchannel_recog_done. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio: incorrect status check in interrogate functionPeter Oberparleiter
Fix incorrect check for active I/O in interrogate function. Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio: fix rc generation after chsc callSebastian Ott
In some situations a rc in __chsc_do_secm will be overwritten by another one. This shouldn't do harm since todays callers don't check for _specific_ errors but fix it for the sake of correctness. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio: fix wrong buffer access in cio_ignore_writeSebastian Ott
Writing only spaces to /proc/cio_ignore will cause a buffer overflow since the size_t value i will not become negative and so buf[-1UL] is accessed. Change the value of i to ssize_t. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio: ccw group fix unbind behaviour.Sebastian Ott
For a ccw group device unbinding it from its driver should do the same as a call to ungroup, since this virtual device can not exist without a driver. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio: fix sanity checks in ccwgroup driver.Sebastian Ott
Some sanity checks in the ccw group driver test the output of container_of macros to be !NULL. Test the input parameters instead. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio: ccw group online store - report rcs to the caller.Sebastian Ott
In case the ccw group driver refuses to set a device [on|off]line, we should transmit the return code to the caller. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio: airq - fix array boundarySebastian Ott
MAX_ISC is a valid isc number, so arrays with an index of isc need to have a length of MAX_ISC+1 Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio: device scan oom fallback.Sebastian Ott
Since some callers rely on for_each_subchannel_staged to not fail, fall back to brute force scanning using get_subchannel_by_schid in case of a oom situation. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio: ensure single load of irq handler pointerHeiko Carstens
Add barrier to prevent compiler from reloading pointer to irq handler. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio/crw: add/fix lockingHeiko Carstens
The crw_unregister_handler uses xchg + synchronize_sched when unregistering a crw_handler. This doesn't protect crw_collect_info to potentially jump to NULL since it has unlocked code like this: if (crw_handlers[i]) crw_handlers[i](NULL, NULL, 1); So add a mutex which protects the crw handler array for changes. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio: ccw device online store - report rc from ccw driver.Sebastian Ott
In case the ccw driver refuses to set a device offline, we should transmit the return code to the caller. Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio: Use ccw_device_set_notoper().Cornelia Huck
Use ccw_device_set_notoper() (which also deletes the device timer and disables the subchannel) instead of simply setting the state to DEV_STATE_NOT_OPER in the generic not operational handling code. This prevents unexpected interrupts popping up for devices that are deemed not operational. Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio: Try harder to disable subchannel.Cornelia Huck
Acting upon the assumption that cio_disable_subchannel() is only called when we really want to disable the subchannel (a) remove the check for activity (it is already done in ccw_device_offline(), which is the place where it matters) (b) collect pending status via tsch() and ignore it (it can't matter anymore since the subchannel will be disabled). Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] cio: Use unbind/bind instead of unregister/register.Cornelia Huck
The common I/O layer may encounter a situation where the device number of a ccw device has changed or a device driver doesn't want to keep a formerly disconnected device becoming operational again. Instead of using device_del()/ device_add() as now, we can just unbind the driver from the device and rebind it to get the desired effect (rebinding) with less overhead. Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] split/move machine check handler codeHeiko Carstens
Split machine check handler code and move it to cio and kernel code where it belongs to. No functional change. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] ftrace: dont trace machine check handlerHeiko Carstens
The ftrace code is currently not reentrant, so we better don't trace our machine check handler. Machine checks are handled like NMIs on s390. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] delete drivers/s390/ebcdic.cHeiko Carstens
Dead file. Seems to be a leftover from the 2.4->2.5 conversion. The used and uptodate version of this file is in arch/s390/kernel. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] move sysinfo.c from drivers/s390 to arch/s390/kernelHeiko Carstens
All in sysinfo.c is core kernel code and not driver code. So move it to arch/s390/kernel. Also includes some small cleanups. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] dasd: message cleanupStefan Haberland
Moved some Messages into s390 debug feature and changed remaining messages to use the dev_xxx and pr_xxx macros. Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] dasd: add High Performance FICON supportStefan Weinhuber
To support High Performance FICON, the DASD device driver has to translate I/O requests into the new transport mode control words (TCW) instead of the traditional (command mode) CCW requests. Signed-off-by: Stefan Weinhuber <wein@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] dasd: add large volume supportStefan Weinhuber
The dasd device driver will now support ECKD devices with more then 65520 cylinders. In the traditional ECKD adressing scheme each track is addressed by a 16-bit cylinder and 16-bit head number. The new addressing scheme makes use of the fact that the actual number of heads is never larger then 15, so 12 bits of the head number can be redefined to be part of the cylinder address. Signed-off-by: Stefan Weinhuber <wein@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] dasd_eckd / Write format R0 is now allowed BBJean-Baptiste Joret
Permission is now granted to the subsystem to format write R0 with: * an ID = CCHHR, where CC = physical cylinder number, HH = physical head number, and R = 0 * a key length of zero * a data length of eight * a data field containing all zeros Signed-off-by: Jean-Baptiste Joret <joret@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] dasd: enable compat ioctlsHeiko Carstens
All of the ioctls are compatible. Just enable them. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26[S390] Automatic IPL after dumpFrank Munzert
Provide new shutdown action "dump_reipl" for automatic ipl after dump. Signed-off-by: Frank Munzert <munzert@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2009-03-25qeth: fix wait_event_timeout handlingHeiko Carstens
wait_event_timeout just takes the numnber of jiffies to wait as an argument. That value does not include jiffies itself. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-25qeth: check for completion of a running recoveryUrsula Braun
When a recovery is started for a qeth device, additional invocations to change a mac address, to configure a VLAN interface on top, or to add multicast addresses should wait till recovery is finished, otherwise recovery might fail. Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com> Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-25qeth: unregister MAC addresses during recovery.Klaus-Dieter Wacker
qeth: Unregister MAC addresses from device (layer 2) during recovery cycle. When the device is set online the MAC addresses are registered again on the device. Signed-off-by: Klaus-Dieter Wacker <kdwacker@de.ibm.com> Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-25qeth: remove EDDPFrank Blaschka
Performance measurements showed EDDP does not lower CPU costs but increase them. So we dump out EDDP code from qeth driver. Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-25qeth: add statistics for tx csumFrank Blaschka
Add statistics counter for software tx checksumming. Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-25qeth: struct device - replace bus_id with dev_name(), dev_set_name()Kay Sievers
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-03-24sysfs: only allow one scheduled removal callback per kobjAlex Chiang
The only way for a sysfs attribute to remove itself (without deadlock) is to use the sysfs_schedule_callback() interface. Vegard Nossum discovered that a poorly written sysfs ->store callback can repeatedly schedule remove callbacks on the same device over and over, e.g. $ while true ; do echo 1 > /sys/devices/.../remove ; done If the 'remove' attribute uses the sysfs_schedule_callback API and also does not protect itself from concurrent accesses, its callback handler will be called multiple times, and will eventually attempt to perform operations on a freed kobject, leading to many problems. Instead of requiring all callers of sysfs_schedule_callback to implement their own synchronization, provide the protection in the infrastructure. Now, sysfs_schedule_callback will only allow one scheduled callback per kobject. On subsequent calls with the same kobject, return -EAGAIN. This is a short term fix. The long term fix is to allow sysfs attributes to remove themselves directly, without any of this callback hokey pokey. [cornelia.huck@de.ibm.com: s390 ccwgroup bits] Reported-by: vegard.nossum@gmail.com Signed-off-by: Alex Chiang <achiang@hp.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>