When we cat <debugfs>/tracing/stack_trace, we may cause circular lock:
sys_read()
t_start()
arch_spin_lock(&max_stack_lock);
t_show()
seq_printf(), vsnprintf() .... /* they are all trace-able,
when they are traced, max_stack_lock may be required again. */
The following script can trigger this circular dead lock very easy:
#!/bin/bash
echo 1 > /proc/sys/kernel/stack_tracer_enabled
mount -t debugfs xxx /mnt > /dev/null 2>&1
(
# make check_stack() zealous to require max_stack_lock
for ((; ;))
{
echo 1 > /mnt/tracing/stack_max_size
}
) &
for ((; ;))
{
cat /mnt/tracing/stack_trace > /dev/null
}
To fix this bug, we increase the percpu trace_active before
require the lock.
Reported-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
LKML-Reference: <4B67D4F9.9080905@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
IRQ autoprobing hasn't actually worked for us at all since very early in
2.6, but no one seems to have noticed given that none of the drivers
that use it see much testing.
yenta_socket is the odd one out, and that depends on PCI IRQs which are
fixed on all SH platforms anyways. Consequently, turning off autoprobing
fixes up crashes triggered by yenta_socket and at least gets it working
again on r7785rp.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
highlander and r2d are the only remaining ones that were blocking
sparseirq being turned on by default, but it turns out that they already
work fine with it by virtue of register_intc_controller(). As such, we
can kill off the dependencies and turn it on by default.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This uses the new create_irq_nr() to build up the FPGA's desired virtual
IRQ mapping and permits us to finally flip on sparseirq for this board.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This just reworks the existing create_irq_on_node() in to the new
create_irq_nr() which is generally exposed. This permits boards that
haven't converted over to sparseirq to try and use their existing ranges,
rather than having arbitrary vectors assigned to them.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
String constants that are continued on subsequent lines with \
are not good.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This improves power management for the SIUA controller on sh7722. Similar
patches might be desired for other SIU-enabled SH platforms.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch extends the sh_flctl driver with support
for 16-bit bus configuration using SEL_16BIT and
support for multiplexed pins using SHBUSSEL.
Signed-off-by: Magnus Damm <damm@opensource.se>
Acked-by: Yoshihiro Shimoda <shimoda.yoshihiro@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch contains a few changes for the sh_flctl driver:
- not sh7723-only driver - get rid of kconfig dependency
- use dev_err() instead of printk()
- use __devinit and __devexit for probe()/remove()
- fix probe() return values
Signed-off-by: Magnus Damm <damm@opensource.se>
Acked-by: Yoshihiro Shimoda <shimoda.yoshihiro@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch improves disable_controller() in the r8a66597-hdc
driver to disable all interrupts and clear status flags. It
also makes sure that disable_controller() is called during
probe(). This fixes the relatively rare case of unexpected
pending interrupts after kexec reboot.
Signed-off-by: Magnus Damm <damm@opensource.se>
Acked-by: Yoshihiro Shimoda <shimoda.yoshihiro@renesas.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
The spi_sh_msiof.c driver presently misconfigures REDG and TEDG. TEDG==0
outputs data at the **rising edge** of the clock and REDG==0 samples data
at the **falling edge** of the clock. Therefore for SPI, TEDG must be
equal to REDG, otherwise the last byte received is not sampled in SPI
mode 3.
This brings the driver in line with the SH7723 HW Reference Manual
settings documented in Figures 20.20 and 20.21 ("SPI Clock and data
timing").
Signed-off-by: Markus Pietrek <Markus.Pietrek@emtrion.de>
Acked-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
We always need to flush the disk write cache and can't skip it just because
the no inode attributes have changed.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <david@fromorbit.com>
dquots are never flushed asynchronously. Remove the flag and the
async write support from the flush function. Make the default flush
a delwri flush to make the inode flush code, which leaves the
XFS_QMOPT_SYNC the only flag remaining. Convert that to use
SYNC_WAIT instead, just like the inode flush code.
V2:
- just pass flush flags straight through
Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
In the transmit path of firewire-net (IPv4 over 1394), the following
race condition may occur:
- The networking soft IRQ inserts a datagram into the 1394 async
request transmit DMA.
- The 1394 async transmit completion tasklet runs to finish cleaning
up (unlink datagram from list of pending ones, release skb and
outbound 1394 transaction object) --- before the networking soft IRQ
had a chance to proceed and add the datagram to the list of pending
datagrams.
This caused a panic in the 1394 async transmit completion tasklet when
it dereferenced unitialized list heads:
http://bugzilla.kernel.org/show_bug.cgi?id=15077
The fix is to add checks in the tx soft IRQ and in the tasklet to
determine which of these two is the last referrer to the transaction
object. Then handle the cleanup of the object by the last referrer
rather than assuming that the tasklet is always the last one.
There is another similar race: Between said tasklet and fwnet_close,
i.e. at ifdown. However, that race is much less likely to occur in
practice and shall be fixed in a separate update.
Reported-by: Илья Басин <basinilya@gmail.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Commit c98929c07a removed the clearing of the FPSCR[31:28] bits from the
vfp_raise_exceptions() function and the new bits are or'ed with the old
FPSCR bits leading to unexpected results (the original commit was
referring to the cumulative bits - FPSCR[4:0]).
Reported-by: Tom Hameenanttila <tmhameen@marvell.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The previous changeset left behind an unused inode variable.
This patch removes it.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
As the padlock driver for SHA uses a software fallback to perform
partial hashing, it must implement custom import/export functions.
Otherwise hmac which depends on import/export for prehashing will
not work with padlock-sha.
Reported-by: Wolfgang Walter <wolfgang.walter@stwm.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
No other driver does anything remotely like this that I know of except
for the tty drivers, and I can't see any reason for random/urandom to do
it. In fact, it's a (trivial, harmless) timing information leak. And
obviously, it generates power- and flash-cycle wasting I/O, especially
if combined with something like hwrngd. Also, it breaks ubifs's
expectations.
Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
DBDMA descriptors need to be located at 32-byte aligned addresses;
however kmalloc in conjunction with the SLAB allocator and
CONFIG_DEBUG_SLUB enabled doesn't deliver any. The dbdma code works
around that by allocating a larger area and realigning the start
address within it.
When freeing a channel however this adjustment is not taken into
account which results in an oops:
Kernel bug detected[#1]:
[...]
Call Trace:
[<80186010>] cache_free_debugcheck+0x284/0x318
[<801869d8>] kfree+0xe8/0x2a0
[<8010b31c>] au1xxx_dbdma_chan_free+0x2c/0x7c
[<80388dc8>] au1x_pcm_dbdma_free+0x34/0x4c
[<80388fa8>] au1xpsc_pcm_close+0x28/0x38
[<80383cb8>] soc_codec_close+0x14c/0x1cc
[<8036dbb4>] snd_pcm_release_substream+0x60/0xac
[<8036dc40>] snd_pcm_release+0x40/0xa0
[<8018c7a8>] __fput+0x11c/0x228
[<80188f60>] filp_close+0x7c/0x98
[<80189018>] sys_close+0x9c/0xe4
[<801022a0>] stack_done+0x20/0x3c
Fix this by recording the address delivered by kmalloc() and using
it as parameter to kfree().
This fix is only necessary with the SLAB allocator and CONFIG_DEBUG_SLAB
enabled; non-debug SLAB, SLUB do return nicely aligned addresses,
debug-enabled SLUB currently panics early in the boot process.
Signed-off-by: Manuel Lauss <manuel.lauss@gmail.com>
To: Linux-MIPS <linux-mips@linux-mips.org>
Cc: Manuel Lauss <manuel.lauss@gmail.com>
Patchwork: http://patchwork.linux-mips.org/patch/878/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6:
ASoC: AM3517: ASoC driver not getting compiled
ASoC: AIC23: Fixing writes to non-existing registers in resume function
ALSA: hda - Add an ASUS mobo to MSI blacklist
* 'drm-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6:
drm/radeon/kms: Fix oops after radeon_cs_parser_init() failure.
drm/radeon/kms: move radeon KMS on/off switch out of staging.
drm/radeon/kms: Bailout of blit if error happen & protect with mutex V3
drm/vmwgfx: Don't send bad flags to the host
drm/vmwgfx: Request SVGA version 2 and bail if not found
drm/vmwgfx: Correctly detect 3D
drm/ttm: remove unnecessary save_flags and ttm_flag_masked in ttm_bo_util.c
drm/kms: Remove incorrect comment in struct drm_mode_modeinfo
drm/ttm: remove padding from ttm_ref_object on 64bit builds
drm/radeon/kms: release agp on error.
drm/kms/radeon/agp: Move the check of the aper_size after drm_acp_acquire and drm_agp_info
drm/kms/radeon/agp: Fix warning, format ‘%d’ expects type ‘int’, but argument 4 has type ‘size_t’
drm/ttm: Avoid conflicting reserve_memtype during ttm_tt_set_page_caching.
drm/kms/radeon: pick digitial encoders smarter. (v3)
drm/radeon/kms: use active device to pick connector for encoder
drm/radeon/kms: fix incorrect logic in DP vs eDP connector checking.
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
perf, hw_breakpoint, kgdb: Do not take mutex for kernel debugger
x86, hw_breakpoints, kgdb: Fix kgdb to use hw_breakpoint API
hw_breakpoints: Release the bp slot if arch_validate_hwbkpt_settings() fails.
perf: Ignore perf.data.old
perf report: Fix segmentation fault when running with '-g none'
* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
sched: Correct printk whitespace in warning from cpu down task check
sched: Fix incorrect sanity check
sched: Fix fork vs hotplug vs cpuset namespaces
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
tracing/documentation: Cover new frame pointer semantics
tracing/documentation: Fix a typo in ftrace.txt
ring-buffer: Check for end of page in iterator
ring-buffer: Check if ring buffer iterator has stale data
tracing: Prevent kernel oops with corrupted buffer
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86/agp: Fix agp_amd64_init regression
x86: Add quirk for Intel DG45FC board to avoid low memory corruption
x86: Add Dell OptiPlex 760 reboot quirk
x86, UV: Fix RTC latency bug by reading replicated cachelines
oprofile/x86: add Xeon 7500 series support
oprofile/x86: fix crash when profiling more than 28 events
lib/dma-debug.c: mark file-local struct symbol static.
x86/amd-iommu: Fix deassignment of a device from the pt_domain
x86/amd-iommu: Fix IOMMU-API initialization for iommu=pt
x86/amd-iommu: Fix NULL pointer dereference in __detach_device()
x86/amd-iommu: Fix possible integer overflow
The WM8350 LED driver needs to be able to enable and disable the
regulators it is using. Previously the core wasn't properly enforcing
status change constraints so the driver was able to function but this
has always been intended to be required.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: stable@kernel.org
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
The SH7780 PCI controller supports 3 different ranges of PCI memory in
addition to its PCI I/O window. In the case of 29-bit mode, only 2 memory
windows are supported, while in 32-bit mode all 3 are visible. This
attempts to make the resource handling completely dynamic and to permit
platforms to map in as many apertures as they can handle.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
ince gfs2 writes the rindex file a block at a time, and releases the
exclusive lock after each block, it is possible that another process
will grab the lock in the middle of the write. Since rindex entries are
not an even divisor of blocks, that other process may see partial
entries. On grows, this is fine. The process can simply ignore the the
partial entires. Previously, the code withdrew when it saw partial
entries. Now it simply ignores them.
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
These were never handled before, so implement some common infrastructure
to support them, then make use of that in the SH7780-specific code. In
practice there is little here that can not be generalized for SH4 parts,
which will be an incremental change as the 7780/7751 code is gradually
unified.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
When CONFIG_HAVE_UNSTABLE_SCHED_CLOCK is set, sched_clock() gets
the time from hardware such as the TSC on x86. In this
configuration kgdb will report a softlock warning message on
resuming or detaching from a debug session.
Sequence of events in the problem case:
1) "cpu sched clock" and "hardware time" are at 100 sec prior
to a call to kgdb_handle_exception()
2) Debugger waits in kgdb_handle_exception() for 80 sec and on
exit the following is called ... touch_softlockup_watchdog() -->
__raw_get_cpu_var(touch_timestamp) = 0;
3) "cpu sched clock" = 100s (it was not updated, because the
interrupt was disabled in kgdb) but the "hardware time" = 180 sec
4) The first timer interrupt after resuming from
kgdb_handle_exception updates the watchdog from the "cpu sched clock"
update_process_times() { ... run_local_timers() -->
softlockup_tick() --> check (touch_timestamp == 0) (it is "YES"
here, we have set "touch_timestamp = 0" at kgdb) -->
__touch_softlockup_watchdog() ***(A)--> reset "touch_timestamp"
to "get_timestamp()" (Here, the "touch_timestamp" will still be
set to 100s.) ...
scheduler_tick() ***(B)--> sched_clock_tick() (update "cpu sched
clock" to "hardware time" = 180s) ... }
5) The Second timer interrupt handler appears to have a large
jump and trips the softlockup warning.
update_process_times() { ... run_local_timers() -->
softlockup_tick() --> "cpu sched clock" - "touch_timestamp" =
180s-100s > 60s --> printk "soft lockup error messages" ... }
note: ***(A) reset "touch_timestamp" to
"get_timestamp(this_cpu)"
Why is "touch_timestamp" 100 sec, instead of 180 sec?
When CONFIG_HAVE_UNSTABLE_SCHED_CLOCK is set, the call trace of
get_timestamp() is:
get_timestamp(this_cpu)
-->cpu_clock(this_cpu)
-->sched_clock_cpu(this_cpu)
-->__update_sched_clock(sched_clock_data, now)
The __update_sched_clock() function uses the GTOD tick value to
create a window to normalize the "now" values. So if "now"
value is too big for sched_clock_data, it will be ignored.
The fix is to invoke sched_clock_tick() to update "cpu sched
clock" in order to recover from this state. This is done by
introducing the function touch_softlockup_watchdog_sync(). This
allows kgdb to request that the sched clock is updated when the
watchdog thread runs the first time after a resume from kgdb.
[yong.zhang0@gmail.com: Use per cpu instead of an array]
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Dongdong Deng <Dongdong.Deng@windriver.com>
Cc: kgdb-bugreport@lists.sourceforge.net
Cc: peterz@infradead.org
LKML-Reference: <1264631124-4837-2-git-send-email-jason.wessel@windriver.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
register_pci_controller() can fail, but presently is a void function.
Change this over to an int so that we can bail early before continuing on
with post-registration initialization (such as throwing the controller in
to 66MHz mode in the case of the SH7780 host controller).
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This adds some helper glue for scanning the bus and determining if all
of the devices are 66MHz capable or not before flipping on 66MHz mode.
This isn't quite to spec, but it's fairly consistent with what other
embedded controllers end up having to do.
Scanning code cribbed from the MIPS txx9 PCI code.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
