Currently the omap serial clocks are autoidled after 5 seconds.
However, this causes lost characters on the serial ports. As this
is considered non-standard behaviour for Linux, disable the timeout.
Note that this will also cause blocking of any deeper omap sleep
states.
To enable the autoidling of the serial ports, do something like
this for each serial port:
# echo 5 > /sys/devices/platform/serial8250.0/sleep_timeout
# echo 5 > /sys/devices/platform/serial8250.1/sleep_timeout
...
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
I have found an access to already released memory in
clk_debugfs_register_one() function.
Signed-off-by: Marek Skuczynski <mareksk7@gmail.com>
Acked-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
David Binderman ran the sourceforge tool cppcheck over the source code of the
new Linux kernel 2.6.33-rc6:
[./arm/mach-omap2/mux.c:492]: (error) Buffer access out-of-bounds
13 characters + 1 digit + 1 zero byte is more than 14 characters.
Also add a comment on mode0 name length in case new omaps
start using longer names.
Reported-by: David Binderman <dcb314@hotmail.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
3630 has more mux signals than 34xx. The additional pins
exist in omap36xx_cbp_subset, but are not initialized
as the superset is missing these offsets. This causes
the following errors during the boot:
mux: Unknown entry offset 0x236
mux: Unknown entry offset 0x22e
mux: Unknown entry offset 0x1ec
mux: Unknown entry offset 0x1ee
mux: Unknown entry offset 0x1f4
mux: Unknown entry offset 0x1f6
mux: Unknown entry offset 0x1f8
mux: Unknown entry offset 0x1fa
mux: Unknown entry offset 0x1fc
mux: Unknown entry offset 0x22a
mux: Unknown entry offset 0x226
mux: Unknown entry offset 0x230
mux: Unknown entry offset 0x22c
mux: Unknown entry offset 0x228
Fix this by adding the missing offsets to omap3 superset.
Note that additionally the uninitialized pins need to be
skipped on 34xx.
Based on an earlier patch by Allen Pais <allen.pais@ti.com>.
Reported-by: Allen Pais <allen.pais@ti.com>
Signed-off-by: Allen Pais <allen.pais@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Ensure valid clock pointer during GPMC init. Fixes compiler
warning about potential use of uninitialized variable.
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Ensure valid base address during IRQ init. Fixes compiler warning
about potential use of uninitialized variable.
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
OMAP platforms(like OMAP3530) include DSP or other co-processors
for media acceleration. when carving out memory for the
accelerators we can end up creating a hole in the memory map
of sort:
<kernel memory><hole(memory for accelerator)><kernel memory>
To handle such a memory configuration ARCH_HAS_HOLES_MEMORYMODEL
has to be enabled. For further information refer discussion at:
http://www.mail-archive.com/linux-omap@vger.kernel.org/msg15262.html.
Signed-off-by: Sriramakrishnan <srk@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
The WARN_ON in lookup_pi_state which complains about a mismatch
between pi_state->owner->pid and the pid which we retrieved from the
user space futex is completely bogus.
The code just emits the warning and then continues despite the fact
that it detected an inconsistent state of the futex. A conveniant way
for user space to spam the syslog.
Replace the WARN_ON by a consistency check. If the values do not match
return -EINVAL and let user space deal with the mess it created.
This also fixes the missing task_pid_vnr() when we compare the
pi_state->owner pid with the futex value.
Reported-by: Jermome Marchand <jmarchan@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Darren Hart <dvhltc@us.ibm.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: <stable@kernel.org>
If the owner of a PI futex dies we fix up the pi_state and set
pi_state->owner to NULL. When a malicious or just sloppy programmed
user space application sets the futex value to 0 e.g. by calling
pthread_mutex_init(), then the futex can be acquired again. A new
waiter manages to enqueue itself on the pi_state w/o damage, but on
unlock the kernel dereferences pi_state->owner and oopses.
Prevent this by checking pi_state->owner in the unlock path. If
pi_state->owner is not current we know that user space manipulated the
futex value. Ignore the mess and return -EINVAL.
This catches the above case and also the case where a task hijacks the
futex by setting the tid value and then tries to unlock it.
Reported-by: Jermome Marchand <jmarchan@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Darren Hart <dvhltc@us.ibm.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: <stable@kernel.org>
This fixes a futex key reference count bug in futex_lock_pi(),
where a key's reference count is incremented twice but decremented
only once, causing the backing object to not be released.
If the futex is created in a temporary file in an ext3 file system,
this bug causes the file's inode to become an "undead" orphan,
which causes an oops from a BUG_ON() in ext3_put_super() when the
file system is unmounted. glibc's test suite is known to trigger this,
see <http://bugzilla.kernel.org/show_bug.cgi?id=14256>.
The bug is a regression from 2.6.28-git3, namely Peter Zijlstra's
38d47c1b70 "[PATCH] futex: rely on
get_user_pages() for shared futexes". That commit made get_futex_key()
also increment the reference count of the futex key, and updated its
callers to decrement the key's reference count before returning.
Unfortunately the normal exit path in futex_lock_pi() wasn't corrected:
the reference count is incremented by get_futex_key() and queue_lock(),
but the normal exit path only decrements once, via unqueue_me_pi().
The fix is to put_futex_key() after unqueue_me_pi(), since 2.6.31
this is easily done by 'goto out_put_key' rather than 'goto out'.
Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Darren Hart <dvhltc@us.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@kernel.org>
If the NFS_ATTR_FATTR_TYPE field isn't set in fattr->valid, then we should
not set the S_IFMT part of inode->i_mode.
Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Ensure that we unregister the bdi before kill_anon_super() calls
ida_remove() on our device name.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org
The VM/VFS does not allow mapping->a_ops->invalidatepage() to fail.
Unfortunately, nfs_wb_page_cancel() may fail if a fatal signal occurs.
Since the NFS code assumes that the page stays mapped for as long as the
writeback is active, we can end up Oopsing (among other things).
The only safe fix here is to convert nfs_wait_on_request(), so as to make
it uninterruptible (as is already the case with wait_on_page_writeback()).
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org
Interrupts must be disabled while an interrupt state restore
(prep for interrupt return) is in progress.
Code to do this was lost in the port to the mainline kernel.
Signed-off-by: Steven J. Magnani <steve@digidescorp.com>
Signed-off-by: Michal Simek <monstr@monstr.eu>
Although all glocks are, by the time of the umount glock wait,
scheduled for demotion, some of them haven't made it far
enough through the process for the original set of waiting
code to wait for them.
This extends the ref count to the whole glock lifetime in order
to ensure that the waiting does catch all glocks. It does make
it a bit more invasive, but it seems the only sensible solution
at the moment.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This patch adds a wait on umount between the point at which we
dispose of all glocks and the point at which we unmount the
lock protocol. This ensures that we've received all the replies
to our unlock requests before we stop the locking.
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Reported-by: Fabio M. Di Nitto <fdinitto@redhat.com>
During blocked lock processing, we should consider the possibility that the
lock is no longer blocking.
Joel Becker <joel.becker@oracle.com> assisted in fixing this issue.
Reported-by: David Teigland <teigland@redhat.com>
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
During upconvert, if the master were to send a BAST, dlmglue will detect the
upconversion in process and send a cancel convert to the master. Upon receiving
the AST for the cancel convert, it will re-process the lock resource to determine
whether it needs downconverting. Say, the up was from PR to EX and the BAST was
for EX. After the cancel convert, it will need to downconvert to NL.
However, if the node was originally upconverting from NL to EX, then there would
be no reason to downconvert (assuming the same message sequence).
This patch makes dlmglue consider the possibility that the current lock level
is already compatible and that downconverting is not required.
Joel Becker <joel.becker@oracle.com> assisted in fixing this issue.
Fixes ossbz#1178
http://oss.oracle.com/bugzilla/show_bug.cgi?id=1178
Reported-by: Coly Li <coly.li@suse.de>
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
There is possibility of a livelock in __ocfs2_cluster_lock(). If a node were
to get an ast for an upconvert request, followed immediately by a bast,
there is a small window where the fs may downconvert the lock before the
process requesting the upconvert is able to take the lock.
This patch adds a new flag to indicate that the upconvert is still in
progress and that the dc thread should not downconvert it right now.
Wengang Wang <wen.gang.wang@oracle.com> and Joel Becker
<joel.becker@oracle.com> contributed heavily to this patch.
Reported-by: David Teigland <teigland@redhat.com>
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
During bast, set the OCFS2_LOCK_BLOCKED flag only if the lock needs to
downconverted.
Signed-off-by: Wengang Wang <wen.gang.wang@oracle.com>
Acked-by: Sunil Mushran <sunil.mushran@oracle.com>
Acked-by: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
Although we use u64 to pass userspace pointers to the kernel
to avoid compat_ioctl, it doesn't work in some ppc platform.
So wrap them with compat_ptr and add compat_ioctl.
The detailed discussion about compat_ptr can be found in thread
http://lkml.org/lkml/2009/10/27/423.
We indeed met with a bug when testing on ppc(-EFAULT is returned
when using old_path). This patch try to fix this.
I have tested in ppc64(with 32 bit reflink) and x86_64(with i686
reflink), both works.
Signed-off-by: Tao Ma <tao.ma@oracle.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
Mainline commit aad1b15310 made the
dlm_begin_reco_handler() return -EAGAIN instead of EAGAIN.
As this error is transmitted over the wire, we want the receiver,
dlm_send_begin_reco_message(), to understand both the older EAGAIN and
the newer -EAGAIN, to allow rolling upgrade of the cluster nodes.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
In CoW, we have to make sure that the page is already written
out to the disk. So we have a BUG_ON(PageDirty(page)).
In ppc platform we have pagesize=64K, so if the cs=4K, if the
file have fragmented clusters, we will map the page many times.
See this file as an example.
Tree Depth: 0 Count: 19 Next Free Rec: 14
## Offset Clusters Block# Flags
0 0 4 2164864 0x2 Refcounted
1 4 2 9302792 0x2 Refcounted
...
We have to replace the extent recs one by one, so the page with index 0
will be mapped and dirtied twice.
I'd like to leave the BUG_ON there while adding a check so that in
case we meet with an error in other platforms, we can find it easily.
Signed-off-by: Tao Ma <tao.ma@oracle.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
In ocfs2_duplicate_clusters_by_page, we calculate map_end
by shifting page_index. But actually in case we meet with
a large offset(say in a i686 box, poff_t is only 32 bits
and page_index=2056240), we will overflow. So change the
type of page_index to loff_t.
Signed-off-by: Tao Ma <tao.ma@oracle.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (23 commits)
connector: Delete buggy notification code.
be2net: use eq-id to calculate cev-isr reg offset
Bluetooth: Use the control channel for raw HID reports
Bluetooth: Add DFU driver for Atheros Bluetooth chipset AR3011
Bluetooth: Redo checks in IRQ handler for shared IRQ support
Bluetooth: Fix memory leak in L2CAP
Bluetooth: Remove double free of SKB pointer in L2CAP
cdc_ether: Partially revert "usbnet: Set link down initially ..."
be2net: Fix memset() arg ordering.
bonding: bond_open error return value
ixgbe: if ixgbe_copy_dcb_cfg is going to fail learn about it early
ixgbe: set the correct DCB bit for pg tx settings
igbvf: fix issue w/ mapped_as_page being left set after unmap
drivers/net: ks8851_mll ethernet network driver
be2net: Bug fix to support newer generation of BE ASIC
starfire: clean up properly if firmware loading fails
mac80211: fix NULL pointer dereference when ftrace is enabled
netfilter: ctnetlink: fix expectation mask dump
ipv6: conntrack: Add member of user to nf_ct_frag6_queue structure
ath9k: fix eeprom INI values override for 2GHz-only cards
...
This is the counterpart to cba767175b
("pktcdvd: remove broken dev_t export of class devices"). Device is not
registered using dev_t, so it should not be destroyed using device_destroy
which looks up the device by dev_t. This will fail and adding the device
again will fail with the "duplicate name" error. This is fixed using
device_unregister instead of device_destroy.
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Peter Osterlund <petero2@telia.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Newly added memory can not be accessed via /dev/mem, because we do not
update the variables high_memory, max_pfn and max_low_pfn.
Add a function update_end_of_memory_vars() to update these variables for
64-bit kernels.
[akpm@linux-foundation.org: simplify comment]
Signed-off-by: Shaohui Zheng <shaohui.zheng@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Li Haicheng <haicheng.li@intel.com>
Reviewed-by: Wu Fengguang <fengguang.wu@intel.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
init_fault_attr_entries() should be init_fault_attr_dentries().
cleanup_fault_attr_entries() should be cleanup_fault_attr_dentries().
Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
hugetlb_sysfs_add_hstate is called by hugetlb_register_node directly
during init and also indirectly via sysfs after init.
This patch removes the __init tag from hugetlb_sysfs_add_hstate.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Cc: Lee Schermerhorn <lee.schermerhorn@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The probe function passes a pointer to a struct fb_info to
platform_set_drvdata(), so don't interpret the return value of
platform_get_drvdata() as a pointer to struct imxfb_info.
The original imxfb_info *fbi backlight_power was NULL but in imxfb_suspend
it was 4 resulting in an oops as imxfb_suspend calls
imxfb_disable_controller(fbi) which in turn has
if (fbi->backlight_power)
fbi->backlight_power(0);
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Sascha Hauer <kernel@pengutronix.de>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In cgroup_create(), if alloc_css_id() returns failure, the errno is not
propagated to userspace, so mkdir will fail silently.
To trigger this bug, we mount blkio (or memory subsystem), and create more
then 65534 cgroups. (The number of cgroups is limited to 65535 if a
subsystem has use_id == 1)
# mount -t cgroup -o blkio xxx /mnt
# for ((i = 0; i < 65534; i++)); do mkdir /mnt/$i; done
# mkdir /mnt/65534
(should return ENOSPC)
#
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Paul Menage <menage@google.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When I use markup_oops.pl parse a x8664 oops, I got:
objdump: --start-address: bad number: NaN
No matching code found
This is because:
main::(./m.pl:228): open(FILE, "objdump -dS --adjust-vma=$vmaoffset --start-address=$decodestart --stop-address=$decodestop $filename |") || die "Cannot start objdump";
DB<3> p $decodestart
NaN
This NaN is from:
main::(./m.pl:176): my $decodestart = Math::BigInt->from_hex("0x$target") - Math::BigInt->from_hex("0x$func_offset");
DB<2> p $func_offset
0x175
There is already a "0x" in $func_offset, another 0x makes it a NaN.
The $func_offset is from line:
if ($line =~ /RIP: 0010:\[\<[0-9a-f]+\>\] \[\<[0-9a-f]+\>\] ([a-zA-Z0-9\_]+)\+(0x[0-9a-f]+)\/0x[a-f0-9]/) {
$function = $1;
$func_offset = $2;
}
I make a patch to change "(0x[0-9a-f]+)\/0x[a-f0-9]/)" to "0x([0-9a-f]+)\/0x[a-f0-9]/)".
Signed-off-by: Hui Zhu <teawater@gmail.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When git has been set to always use color in .gitconfig then I get the
warning message
Bad divisor in main::vcs_assign: 0
This is caused by vcs_file_signoffs not matching any commits due to the
pattern not understand the colour codes. Fix this by telling git log to
never use colour.
Signed-off-by: Richard Kennedy <richard@rsk.demon.co.uk>
Acked-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
write_kmem() used to assume vwrite() always return the full buffer length.
However now vwrite() could return 0 to indicate memory hole. This
creates a bug that "buf" is not advanced accordingly.
Fix it to simply ignore the return value, hence the memory hole.
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Tejun Heo <tj@kernel.org>
Cc: Nick Piggin <npiggin@suse.de>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Otherwise vmalloc_to_page() will BUG().
This also makes the kmem read/write implementation aligned with mem(4):
"References to nonexistent locations cause errors to be returned." Here we
return -ENXIO (inspired by Hugh) if no bytes have been transfered to/from
user space, otherwise return partial read/write results.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The cache alias problem will happen if the changes of user shared mapping
is not flushed before copying, then user and kernel mapping may be mapped
into two different cache line, it is impossible to guarantee the coherence
after iov_iter_copy_from_user_atomic. So the right steps should be:
flush_dcache_page(page);
kmap_atomic(page);
write to page;
kunmap_atomic(page);
flush_dcache_page(page);
More precisely, we might create two new APIs flush_dcache_user_page and
flush_dcache_kern_page to replace the two flush_dcache_page accordingly.
Here is a snippet tested on omap2430 with VIPT cache, and I think it is
not ARM-specific:
int val = 0x11111111;
fd = open("abc", O_RDWR);
addr = mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
*(addr+0) = 0x44444444;
tmp = *(addr+0);
*(addr+1) = 0x77777777;
write(fd, &val, sizeof(int));
close(fd);
The results are not always 0x11111111 0x77777777 at the beginning as expected. Sometimes we see 0x44444444 0x77777777.
Signed-off-by: Anfei <anfei.zhou@gmail.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: <linux-arch@vger.kernel.org>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix kfifo kernel-doc warnings:
Warning(kernel/kfifo.c:361): No description found for parameter 'total'
Warning(kernel/kfifo.c:402): bad line: @ @lenout: pointer to output variable with copied data
Warning(kernel/kfifo.c:412): No description found for parameter 'lenout'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Stefani Seibold <stefani@seibold.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix the kernel oops when dev_dbg is called with mx3_fbi->txd == NULL
Fix the late initialisation of mx3fb->backlight_level. If not, in the
chain of function started by init_fb_chan(), in __blank() call
sdc_set_brightness(mx3fb, mx3fb->backlight_level) that will shut down the
CONTRAST PWM output.
Signed-off-by: Alberto Panizzo <maramaopercheseimorto@gmail.com>
Acked-by: Guennadi Liakhovetski <g.liakhovetski <at> gmx.de>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Eric Paris located a bug in idr. With IDR_BITS of 6, it grows to three
layers when id 4096 is first allocated. When that happens, idr wraps
incorrectly and searches the idr array ignoring the high bits. The
following test code from Eric demonstrates the bug nicely.
#include <linux/idr.h>
#include <linux/kernel.h>
#include <linux/module.h>
static DEFINE_IDR(test_idr);
int init_module(void)
{
int ret, forty95, forty96;
void *addr;
/* add 2 entries both with 4095 as the start address */
again1:
if (!idr_pre_get(&test_idr, GFP_KERNEL))
return -ENOMEM;
ret = idr_get_new_above(&test_idr, (void *)4095, 4095, &forty95);
if (ret) {
if (ret == -EAGAIN)
goto again1;
return ret;
}
if (forty95 != 4095)
printk(KERN_ERR "hmmm, forty95=%d\n", forty95);
again2:
if (!idr_pre_get(&test_idr, GFP_KERNEL))
return -ENOMEM;
ret = idr_get_new_above(&test_idr, (void *)4096, 4095, &forty96);
if (ret) {
if (ret == -EAGAIN)
goto again2;
return ret;
}
if (forty96 != 4096)
printk(KERN_ERR "hmmm, forty96=%d\n", forty96);
/* try to find the 2 entries, noticing that 4096 broke */
addr = idr_find(&test_idr, forty95);
if ((int)addr != forty95)
printk(KERN_ERR "hmmm, after find forty95=%d addr=%d\n", forty95, (int)addr);
addr = idr_find(&test_idr, forty96);
if ((int)addr != forty96)
printk(KERN_ERR "hmmm, after find forty96=%d addr=%d\n", forty96, (int)addr);
/* really weird, the entry which should be at 4096 is actually at 0!! */
addr = idr_find(&test_idr, 0);
if ((int)addr)
printk(KERN_ERR "found an entry at id=0 for addr=%d\n", (int)addr);
idr_remove(&test_idr, forty95);
idr_remove(&test_idr, forty96);
return 0;
}
void cleanup_module(void)
{
}
MODULE_AUTHOR("Eric Paris <eparis@redhat.com>");
MODULE_DESCRIPTION("Simple idr test");
MODULE_LICENSE("GPL");
This happens because when sub_alloc() back tracks it doesn't always do it
step-by-step while the over-the-limit detection assumes step-by-step
backtracking. The logic in sub_alloc() looks like the following.
restart:
clear pa[top level + 1] for end cond detection
l = top level
while (true) {
search for empty slot at this level
if (not found) {
push id to the next possible value
l++
A: if (pa[l] is clear)
failed, return asking caller to grow the tree
if (going up 1 level gives more slots to search)
continue the while loop above with the incremented l
else
C: goto restart
}
adjust id accordingly to the found slot
if (l == 0)
return found id;
create lower level if not there yet
record pa[l] and l--
}
Test A is the fail exit condition but this assumes that failure is
propagated upwared one level at a time but the B optimization path breaks
the assumption and restarts the whole thing with a start value which is
above the possible limit with the current layers. sub_alloc() assumes the
start id value is inside the limit when called and test A is the only exit
condition check, so it ends up searching for empty slot while ignoring
high set bit.
So, for 4095->4096 test, level0 search fails but pa[1] contains a valid
pointer. However, going up 1 level wouldn't give any more empty slot so
it takes C and when the whole thing restarts nobody notices the high bit
set beyond the top level.
This patch fixes the bug by changing the fail exit condition check to full
id limit check.
Based-on-patch-from: Eric Paris <eparis@redhat.com>
Reported-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>