With recent cleanups, there is no place where low level driver
directly manipulates request fields. This means that the 'hard'
request fields always equal the !hard fields. Convert all
rq->sectors, nr_sectors and current_nr_sectors references to
accessors.
While at it, drop superflous blk_rq_pos() < 0 test in swim.c.
[ Impact: use pos and nr_sectors accessors ]
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Tested-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Tested-by: Adrian McMenamin <adrian@mcmen.demon.co.uk>
Acked-by: Adrian McMenamin <adrian@mcmen.demon.co.uk>
Acked-by: Mike Miller <mike.miller@hp.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Cc: Borislav Petkov <petkovbb@googlemail.com>
Cc: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Eric Moore <Eric.Moore@lsi.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Pete Zaitcev <zaitcev@redhat.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Paul Clements <paul.clements@steeleye.com>
Cc: Tim Waugh <tim@cyberelk.net>
Cc: Jeff Garzik <jgarzik@pobox.com>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Alex Dubov <oakad@yahoo.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Dario Ballabio <ballabio_dario@emc.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: unsik Kim <donari75@gmail.com>
Cc: Laurent Vivier <Laurent@lvivier.info>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
There are many [__]blk_end_request() call sites which call it with
full request length and expect full completion. Many of them ensure
that the request actually completes by doing BUG_ON() the return
value, which is awkward and error-prone.
This patch adds [__]blk_end_request_all() which takes @rq and @error
and fully completes the request. BUG_ON() is added to to ensure that
this actually happens.
Most conversions are simple but there are a few noteworthy ones.
* cdrom/viocd: viocd_end_request() replaced with direct calls to
__blk_end_request_all().
* s390/block/dasd: dasd_end_request() replaced with direct calls to
__blk_end_request_all().
* s390/char/tape_block: tapeblock_end_request() replaced with direct
calls to blk_end_request_all().
[ Impact: cleanup ]
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Mike Miller <mike.miller@hp.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Jeff Garzik <jgarzik@pobox.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Alex Dubov <oakad@yahoo.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
tape_3590_offline and tape_34xx_offline are removed and tape_generic_offline
is called directly instead.
Signed-off-by: Frank Munzert <munzert@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
A ccw command that reads or writes several records at once will
usually transfer more data then fits into one page and needs to
address memory areas using a list of indirect data address words
(idaw). All but the first of these areas must start on a 4KB or 2KB
block boundary (depending on the idaw format).
A check for this restriction was missing and has been added with
this patch.
Signed-off-by: Stefan Weinhuber <wein@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The dasd driver can automatically online detected dasds, which
especially important for finding the root device. Currently,
it will wait for each online operation to finish individually,
which may take long if many dasds need to be onlined. When using
the new async framework, these onlining operations can run in
parallel and presence of the root device is ensured by the fact
that prepare_namespace() waits for all async threads to finish.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The QDIO ccw devices are started by ccw_device_start so no timeout
can occur for the interrupt handler. Remove the dead code.
In case of an I/O error set the device state to error and wake up
a possibly running qdio_shutdown waiter.
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
It is a fairly common operation to have a pointer to a work and to need a
pointer to the delayed work it is contained in. In particular, all
delayed works which want to rearm themselves will have to do that. So it
would seem fair to offer a helper function for this operation.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Greg KH <greg@kroah.com>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 64ef895798 ("qeth: remove EDDP")
removed the qeth_core_offl.[hc] files, but ended up doing so by just
patching them to zero size, rather than removing them properly.
Actually remove the files.
Reported-by: Andrew Price <andy@andrewprice.me.uk>
Cc: Frank Blaschka <frank.blaschka@de.ibm.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Start a new device recognition if someone writes to sysfs online attribute
of a boxed ccw device. The current test will fail, since cu_type != 0
for devices which were recognized before.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Return -EAGAIN on writes to sysfs online attribute if the corresponding
ccw device is in transient state.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
If a ccw device did not respond in time during internal io, we set it
into boxed state. With this patch we have the following behaviour:
* the ccw driver will get a notification if the device was online and
goes into the boxed state
* if the device was disconnected and got boxed nothing special is to be
done (it will be handled in reprobing later)
* if the device got boxed while initial sensing it will be unregistered
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Introduce ccw_device_schedule_sch_unregister as a wrapper for queuing
ccw_device_call_sch_unregister on the slow_path_wq. This wrapper
will be used in the next patch.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Wake up even on failed device recognition, since this may be triggered
from a user trying to force a device online. With this patch a write
to the online sysfs attribute will not block for ever but return with
-EAGAIN in this case.
Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Setting ->owner as done currently (pde->owner = THIS_MODULE) is racy
as correctly noted at bug #12454. Someone can lookup entry with NULL
->owner, thus not pinning enything, and release it later resulting
in module refcount underflow.
We can keep ->owner and supply it at registration time like ->proc_fops
and ->data.
But this leaves ->owner as easy-manipulative field (just one C assignment)
and somebody will forget to unpin previous/pin current module when
switching ->owner. ->proc_fops is declared as "const" which should give
some thoughts.
->read_proc/->write_proc were just fixed to not require ->owner for
protection.
rmmod'ed directories will be empty and return "." and ".." -- no harm.
And directories with tricky enough readdir and lookup shouldn't be modular.
We definitely don't want such modular code.
Removing ->owner will also make PDE smaller.
So, let's nuke it.
Kudos to Jeff Layton for reminding about this, let's say, oversight.
http://bugzilla.kernel.org/show_bug.cgi?id=12454
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
* '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
...
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
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>
Tejun Heo