Impact: fix to prevent NMI lockup
If the page fault handler produces a WARN_ON in the modifying of
text, and the system is setup to have a high frequency of NMIs,
we can lock up the system on a failure to modify code.
The modifying of code with NMIs allows all NMIs to modify the code
if it is about to run. This prevents a modifier on one CPU from
modifying code running in NMI context on another CPU. The modifying
is done through stop_machine, so only NMIs must be considered.
But if the write causes the page fault handler to produce a warning,
the print can slow it down enough that as soon as it is done
it will take another NMI before going back to the process context.
The new NMI will perform the write again causing another print and
this will hang the box.
This patch turns off the writing as soon as a failure is detected
and does not wait for it to be turned off by the process context.
This will keep NMIs from getting stuck in this back and forth
of print outs.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Impact: keep kernel text read only
Because dynamic ftrace converts the calls to mcount into and out of
nops at run time, we needed to always keep the kernel text writable.
But this defeats the point of CONFIG_DEBUG_RODATA. This patch converts
the kernel code to writable before ftrace modifies the text, and converts
it back to read only afterward.
The kernel text is converted to read/write, stop_machine is called to
modify the code, then the kernel text is converted back to read only.
The original version used SYSTEM_STATE to determine when it was OK
or not to change the code to rw or ro. Andrew Morton pointed out that
using SYSTEM_STATE is a bad idea since there is no guarantee to what
its state will actually be.
Instead, I moved the check into the set_kernel_text_* functions
themselves, and use a local variable to determine when it is
OK to change the kernel text RW permissions.
[ Update: Ingo Molnar suggested moving the prototypes to cacheflush.h ]
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
This patch creates the weak functions: ftrace_arch_code_modify_prepare
and ftrace_arch_code_modify_post_process that are called before and
after the stop machine is called to modify the kernel text.
If the arch needs to do pre or post processing, it only needs to define
these functions.
[ Update: Ingo Molnar suggested using the name ftrace_arch_code_modify_*
over using ftrace_arch_modify_* ]
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Steven Rostedt found a bug in where in his modified kernel
ftrace was unable to modify the kernel text, due to the PMD
itself having been marked read-only as well in
split_large_page().
The fix, suggested by Linus, is to not try to 'clone' the
reference protection of a huge-page, but to use the standard
(and permissive) page protection bits of KERNPG_TABLE.
The 'cloning' makes sense for the ptes but it's a confused and
incorrect concept at the page table level - because the
pagetable entry is a set of all ptes and hence cannot
'clone' any single protection attribute - the ptes can be any
mixture of protections.
With the permissive KERNPG_TABLE, even if the pte protections
get changed after this point (due to ftrace doing code-patching
or other similar activities like kprobes), the resulting combined
protections will still be correct and the pte's restrictive
(or permissive) protections will control it.
Also update the comment.
This bug was there for a long time but has not caused visible
problems before as it needs a rather large read-only area to
trigger. Steve possibly hacked his kernel with some really
large arrays or so. Anyway, the bug is definitely worth fixing.
[ Huang Ying also experienced problems in this area when writing
the EFI code, but the real bug in split_large_page() was not
realized back then. ]
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Reported-by: Huang Ying <ying.huang@intel.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: fix time warps under vmware
Similar to the check for TSC going backwards in the TSC clocksource,
we also need this check for VMI clocksource.
Signed-off-by: Alok N Kataria <akataria@vmware.com>
Cc: Zachary Amsden <zach@vmware.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: stable@kernel.org
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86, mce: fix ifdef for 64bit thermal apic vector clear on shutdown
x86, mce: use force_sig_info to kill process in machine check
x86, mce: reinitialize per cpu features on resume
x86, rcu: fix strange load average and ksoftirqd behavior
* 'tracing-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
tracing: limit the number of loops the ring buffer self test can make
tracing: have function trace select kallsyms
tracing: disable tracing while testing ring buffer
tracing/function-graph-tracer: trace the idle tasks
* 'for-linus' of git://git390.marist.edu/pub/scm/linux-2.6:
[S390] fix "mem=" handling in case of standby memory
[S390] Fix timeval regression on s390
[S390] sclp: handle empty event buffers
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6:
sound: virtuoso: revert "do not overwrite EEPROM on Xonar D2/D2X"
ALSA: jack - Use card->shortname for input name
ALSA: usb-audio - Workaround for misdetected sample rate with CM6207
ALSA: usb-audio - Fix non-continuous rate detection
sound: usb-audio: fix uninitialized variable with M-Audio MIDI interfaces
Revert "Sound: hda - Restore PCI configuration space with interrupts off"
Remove the gesbc9312.h header since it is unused.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
READ_IMPLIES_EXEC must be set when:
o binary _is_ an executable stack (i.e. not EXSTACK_DISABLE_X)
o processor architecture is _under_ ARMv6 (XN bit is supported from ARMv6)
Signed-off-by: Makito SHIOKAWA <lkhmkt@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Standby memory detected with the sclp interface gets always registered
with add_memory calls without considering the limitationt that the
"mem=" kernel paramater implies.
So fix this and only register standby memory that is below the specified
limit.
This fixes zfcpdump since it uses "mem=32M". In case there is appr.
2GB standby memory present all of usable memory would be used for the
struct pages needed for standby memory.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
commit aa5e97ce4b
[PATCH] improve precision of process accounting.
Introduced a timing regression:
-bash-3.2# time ls
real 0m0.006s
user 0m1.754s
sys 0m1.094s
The problem was introduced by an error in cputime_to_timeval.
Cputime is now 1/4096 microsecond, therefore, we have to divide
the remainder with 4096 to get the microseconds.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Handle a malformed hardware response which some versions of the
Support Element (SE) may present during SE restart and which otherwise
would result in an endless loop in function sclp_dispatch_evbufs.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
When changing the parent of a clock, it is necessary to keep the
clock use counts balanced otherwise things the parent state will
get corrupted. Since we already disable and re-enable the clock,
we might as well use the recursive versions instead.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
*ep->reg_udccs is always set to 0.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Acked-by: Eric Miao <eric.miao@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
In the non highmem case, if two memory banks of 1GB each are provided,
the second bank would evade suppression since its virtual base would
be 0. Fix this by disallowing any memory bank which virtual base
address is found to be lower than PAGE_OFFSET.
Reported-by: Lennert Buytenhek <buytenh@marvell.com>
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This reverts commit 7e86c0e685 ("do not
overwrite EEPROM on Xonar D2/D2X") because it did not actually help with
the problem.
More user reports show that the overwriting of the EEPROM is not
triggered by using this driver but by installing Linux, and that the
installation of any other operating system (even one without any CMI8788
driver) has the same effect. In other words, the presence of this
driver does not have any effect on the occurrence of the error. (So
far, the available evidence seems to point to a BIOS bug.)
Furthermore, it turns out that the EEPROM chip is protected against
stray write commands by the command format and by requiring a separate
write-enable command, so the error scenario in the previous commit (that
SPI writes can be misinterpreted as an EEPROM write command) is not even
theoretically possible.
The mixer control that was removed as a consequence of the previous
commit can only be partially emulated in userspace, which also means it
cannot be seen be the in-kernel OSS API emulation, so it is better to
revert that change.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Cc: <stable@kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Impact: prevent deadlock if ring buffer gets corrupted
This patch adds a paranoid check to make sure the ring buffer consumer
does not go into an infinite loop. Since the ring buffer has been set
to read only, the consumer should not loop for more than the ring buffer
size. A check is added to make sure the consumer does not loop more than
the ring buffer size.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Impact: fix output of function tracer to be useful
The function tracer is pretty useless if KALLSYMS is not configured.
Unless you are good at reading hex values, the function tracer should
select the KALLSYMS configuration.
Also, the dynamic function tracer will fail its self test if KALLSYMS
is not selected.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Impact: fix to prevent hard lockup on self tests
If one of the tracers are broken and is constantly filling the ring
buffer while the test of the ring buffer is running, it will hang
the box. The reason is that the test is a consumer that will not
stop till the ring buffer is empty. But if the tracer is broken and
is constantly producing input to the buffer, this test will never
end. The result is a lockup of the box.
This happened when KALLSYMS was not defined and the dynamic ftrace
test constantly filled the ring buffer, because the filter failed
and all functions were being traced. Something was being called
that constantly filled the buffer.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
block: fix deadlock in blk_abort_queue() for drivers that readd to timeout list
block: fix booting from partitioned md array
block: revert part of 18ce3751cc
cciss: PCI power management reset for kexec
paride/pg.c: xs(): &&/|| confusion
fs/bio: bio_alloc_bioset: pass right object ptr to mempool_free
block: fix bad definition of BIO_RW_SYNC
bsg: Fix sense buffer bug in SG_IO
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/drzeus/mmc:
omap_hsmmc: Change while(); loops with finite version
omap_hsmmc: recover from transfer failures
omap_hsmmc: only MMC1 allows HCTL.SDVS != 1.8V
omap_hsmmc: card detect irq bugfix
sdhci: fix led naming
mmc_test: fix basic read test
s3cmci: Fix hangup in do_pio_write()
Revert "sdhci: force high speed capability on some controllers"
MMC: fix bug - SDHC card capacity not correct
gpio_get_value() returns 0 or nonzero, but getmiso() expects 0 or 1.
Sanitize the value to a 0/1 boolean.
Signed-off-by: Michael Buesch <mb@bu3sch.de>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since I don't work for SUSE any more and the bwalle@suse.de address is
invalid, correct it in the copyright headers and documentation.
Signed-off-by: Bernhard Walle <bernhard.walle@gmx.de>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Build breaks when DELL_LAPTOP=y and POWER_SUPPLY=m. DELL_LAPTOP needs to
depend on POWER_SUPPLY.
dell-laptop.c:(.text+0x1ef3c4): undefined reference to `power_supply_is_system_supplied'
dell-laptop.c:(.text+0x1ef45e): undefined reference to `power_supply_is_system_supplied'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Matthew Garrett <mjg59@srcf.ucam.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Otherwise, these don't work when called from 32-bit userspace on 64-bit
kernels.
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: <stable@kernel.org> [2.6.25.x, 2.6.26.x, 2.6.27.x, 2.6.28.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Submenus of the graphics support "Support for frame buffer devices" and
"Direct Rendering Manager (XFree86 4.1.0 and higher DRI support)" are
broken in half after latest changes for Intel 915 mode setting support.
The DRM subsection is broken because one option is put outside the choice
section it depends on.
The frame buffers part is broken then due to circular dependency. Fix
this by make Intel frame buffers depend on CONFIG_INTEL_AGP.
Kconfigs are broken by d2f5935770
("drm/i915: select framebuffer support automatically").
This is probably not only way to fix this.
Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Dave Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The floppy driver requests an I/O port it doesn't need, and sometimes this
causes a conflict with a motherboard device reported by PNPBIOS.
This patch makes the floppy driver request and release only the ports it
actually uses. It also factors out the request/release stuff and the
io-ports list so they're all in one place now.
The current floppy driver uses only these ports:
0x3f2 (FD_DOR)
0x3f4 (FD_STATUS)
0x3f5 (FD_DATA)
0x3f7 (FD_DCR/FD_DIR)
but it requests 0x3f2-0x3f5 and 0x3f7, which includes the unused port
0x3f3.
Some BIOSes report 0x3f3 as a motherboard resource. The PNP system driver
reserves that, which causes a conflict when the floppy driver requests
0x3f2-0x3f5 later.
Philippe reported that this conflict broke the floppy driver between
2.6.11 and 2.6.22. His PNPBIOS reports these devices:
$ cat 00:07/id 00:07/resources # motherboard device
PNP0c02
state = active
io 0x80-0x80
io 0x10-0x1f
io 0x22-0x3f
io 0x44-0x5f
io 0x90-0x9f
io 0xa2-0xbf
io 0x3f0-0x3f1
io 0x3f3-0x3f3
$ cat 00:03/id 00:03/resources # floppy device
PNP0700
state = active
io 0x3f4-0x3f5
io 0x3f2-0x3f2
Reference:
http://lkml.org/lkml/2009/1/31/162
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Philippe De Muyter <phdm@macqel.be>
Reported-by: Philippe De Muyter <phdm@macqel.be>
Tested-by: Philippe De Muyter <phdm@macqel.be>
Cc: Adam M Belay <abelay@mit.edu>
Cc: Robert Hancock <hancockrwd@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I have a Digi Neo 8 PCI card (114f:00b1) Serial controller: Digi
International Digi Neo 8 (rev 05)
that works with the jsm driver after using the following patch.
Signed-off-by: Adam Lackorzynski <adam@os.inf.tu-dresden.de>
Cc: Scott H Kilau <Scott_Kilau@digi.com>
Cc: Wendy Xiong <wendyx@us.ibm.com>
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Now, early_pfn_in_nid(PFN, NID) may returns false if PFN is a hole.
and memmap initialization was not done. This was a trouble for
sparc boot.
To fix this, the PFN should be initialized and marked as PG_reserved.
This patch changes early_pfn_in_nid() return true if PFN is a hole.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reported-by: David Miller <davem@davemlloft.net>
Tested-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: <stable@kernel.org> [2.6.25.x, 2.6.26.x, 2.6.27.x, 2.6.28.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
What's happening is that the assertion in mm/page_alloc.c:move_freepages()
is triggering:
BUG_ON(page_zone(start_page) != page_zone(end_page));
Once I knew this is what was happening, I added some annotations:
if (unlikely(page_zone(start_page) != page_zone(end_page))) {
printk(KERN_ERR "move_freepages: Bogus zones: "
"start_page[%p] end_page[%p] zone[%p]\n",
start_page, end_page, zone);
printk(KERN_ERR "move_freepages: "
"start_zone[%p] end_zone[%p]\n",
page_zone(start_page), page_zone(end_page));
printk(KERN_ERR "move_freepages: "
"start_pfn[0x%lx] end_pfn[0x%lx]\n",
page_to_pfn(start_page), page_to_pfn(end_page));
printk(KERN_ERR "move_freepages: "
"start_nid[%d] end_nid[%d]\n",
page_to_nid(start_page), page_to_nid(end_page));
...
And here's what I got:
move_freepages: Bogus zones: start_page[2207d0000] end_page[2207dffc0] zone[fffff8103effcb00]
move_freepages: start_zone[fffff8103effcb00] end_zone[fffff8003fffeb00]
move_freepages: start_pfn[0x81f600] end_pfn[0x81f7ff]
move_freepages: start_nid[1] end_nid[0]
My memory layout on this box is:
[ 0.000000] Zone PFN ranges:
[ 0.000000] Normal 0x00000000 -> 0x0081ff5d
[ 0.000000] Movable zone start PFN for each node
[ 0.000000] early_node_map[8] active PFN ranges
[ 0.000000] 0: 0x00000000 -> 0x00020000
[ 0.000000] 1: 0x00800000 -> 0x0081f7ff
[ 0.000000] 1: 0x0081f800 -> 0x0081fe50
[ 0.000000] 1: 0x0081fed1 -> 0x0081fed8
[ 0.000000] 1: 0x0081feda -> 0x0081fedb
[ 0.000000] 1: 0x0081fedd -> 0x0081fee5
[ 0.000000] 1: 0x0081fee7 -> 0x0081ff51
[ 0.000000] 1: 0x0081ff59 -> 0x0081ff5d
So it's a block move in that 0x81f600-->0x81f7ff region which triggers
the problem.
This patch:
Declaration of early_pfn_to_nid() is scattered over per-arch include
files, and it seems it's complicated to know when the declaration is used.
I think it makes fix-for-memmap-init not easy.
This patch moves all declaration to include/linux/mm.h
After this,
if !CONFIG_NODES_POPULATES_NODE_MAP && !CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
-> Use static definition in include/linux/mm.h
else if !CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
-> Use generic definition in mm/page_alloc.c
else
-> per-arch back end function will be called.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Tested-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Reported-by: David Miller <davem@davemlloft.net>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: <stable@kernel.org> [2.6.25.x, 2.6.26.x, 2.6.27.x, 2.6.28.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Li Zefan said:
Thread 1:
for ((; ;))
{
mount -t cpuset xxx /mnt > /dev/null 2>&1
cat /mnt/cpus > /dev/null 2>&1
umount /mnt > /dev/null 2>&1
}
Thread 2:
for ((; ;))
{
mount -t cpuset xxx /mnt > /dev/null 2>&1
umount /mnt > /dev/null 2>&1
}
(Note: It is irrelevant which cgroup subsys is used.)
After a while a lockdep warning showed up:
=============================================
[ INFO: possible recursive locking detected ]
2.6.28 #479
---------------------------------------------
mount/13554 is trying to acquire lock:
(&type->s_umount_key#19){--..}, at: [<c049d888>] sget+0x5e/0x321
but task is already holding lock:
(&type->s_umount_key#19){--..}, at: [<c049da0c>] sget+0x1e2/0x321
other info that might help us debug this:
1 lock held by mount/13554:
#0: (&type->s_umount_key#19){--..}, at: [<c049da0c>] sget+0x1e2/0x321
stack backtrace:
Pid: 13554, comm: mount Not tainted 2.6.28-mc #479
Call Trace:
[<c044ad2e>] validate_chain+0x4c6/0xbbd
[<c044ba9b>] __lock_acquire+0x676/0x700
[<c044bb82>] lock_acquire+0x5d/0x7a
[<c049d888>] ? sget+0x5e/0x321
[<c061b9b8>] down_write+0x34/0x50
[<c049d888>] ? sget+0x5e/0x321
[<c049d888>] sget+0x5e/0x321
[<c045a2e7>] ? cgroup_set_super+0x0/0x3e
[<c045959f>] ? cgroup_test_super+0x0/0x2f
[<c045bcea>] cgroup_get_sb+0x98/0x2e7
[<c045cfb6>] cpuset_get_sb+0x4a/0x5f
[<c049dfa4>] vfs_kern_mount+0x40/0x7b
[<c049e02d>] do_kern_mount+0x37/0xbf
[<c04af4a0>] do_mount+0x5c3/0x61a
[<c04addd2>] ? copy_mount_options+0x2c/0x111
[<c04af560>] sys_mount+0x69/0xa0
[<c0403251>] sysenter_do_call+0x12/0x31
The cause is after alloc_super() and then retry, an old entry in list
fs_supers is found, so grab_super(old) is called, but both functions hold
s_umount lock:
struct super_block *sget(...)
{
...
retry:
spin_lock(&sb_lock);
if (test) {
list_for_each_entry(old, &type->fs_supers, s_instances) {
if (!test(old, data))
continue;
if (!grab_super(old)) <--- 2nd: down_write(&old->s_umount);
goto retry;
if (s)
destroy_super(s);
return old;
}
}
if (!s) {
spin_unlock(&sb_lock);
s = alloc_super(type); <--- 1th: down_write(&s->s_umount)
if (!s)
return ERR_PTR(-ENOMEM);
goto retry;
}
...
}
It seems like a false positive, and seems like VFS but not cgroup needs to
be fixed.
Peter said:
We can simply put the new s_umount instance in a but lockdep doesn't
particularly cares about subclass order.
If there's any issue with the callers of sget() assuming the s_umount lock
being of sublcass 0, then there is another annotation we can use to fix
that, but lets not bother with that if this is sufficient.
Addresses http://bugzilla.kernel.org/show_bug.cgi?id=12673
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Tested-by: Li Zefan <lizf@cn.fujitsu.com>
Reported-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Paul Menage <menage@google.com>
Cc: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I found a problem of handling of modem status of atmel_serial driver.
With the commit 1ecc26 ("atmel_serial: split the interrupt handler"),
handling of modem status signal was splitted into two parts. The
atmel_tasklet_func() compares new status with irq_status_prev, but
irq_status_prev is not correct if signal status was changed while the port
is closed.
Here is a sequence to cause problem:
1. Remote side sets CTS (and DSR).
2. Local side close the port.
3. Local side clears RTS and DTR.
4. Remote side clears CTS and DSR.
5. Local side reopen the port. hw_stopped becomes 1.
6. Local side sets RTS and DTR.
7. Remote side sets CTS and DSR.
Then CTS change interrupt can be received, but since CTS bit in
irq_status_prev and new status is same, uart_handle_cts_change() will not
be called (so hw_stopped will not be cleared, i.e. cannot send any data).
I suppose irq_status_prev should be initialized at somewhere in open
sequence.
Itai Levi pointed out that we need to initialize atmel_port->irq_status
as well here. His analysis is as follows:
> Regarding the second part of the patch (which resets irq_status_prev),
> it turns out that both versions of the patch (mine and Atsushi's)
> still leave enough room for faulty behavior when opening the port.
>
> This is because we are not resetting both irq_status_prev and
> irq_status in atmel_startup() to CSR, which leads faulty behavior in
> the following sequences:
>
> First case:
> 1. closing the port while CTS line = 1 (TX not allowed)
> 2. setting CTS line = 0 (TX allowed)
> 3. opening the port
> 4. transmitting one char
> 5. Cannot transmit more chars, although CTS line is 0
>
> Second case:
> 1. closing the port while CTS line = 0 (TX allowed)
> 2. setting CTS line = 1 (TX not allowed)
> 3. opening the port
> 4. receiving some chars
> 5. Now we can transmit, although CTS line is 1
>
> This reason for this is that the tasklet is scheduled as a result of
> TX or RX interrupts (not a status change!), in steps 4 above. Inside
> the tasklet, the atmel_port->irq_status (which holds the value from
> the previous session) is compared to atmel_port->irq_status_prev.
> Hence, a status-change of the CTS line is faultily detected.
>
> Both cases were verified on 9260 hardware.
[haavard.skinnemoen@atmel.com: folded with patch from Itai Levi]
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Cc: Remy Bohmer <linux@bohmer.net>
Cc: Marc Pignat <marc.pignat@hevs.ch>
Cc: Itai Levi <itai.levi.devel@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The conversion of atmel-mci to dma_request_channel missed the
initialization of the channel dma_slave information. The filter_fn passed
to dma_request_channel is responsible for initializing the channel's
private data. This implementation has the additional benefit of enabling
a generic client-channel data passing mechanism.
Reviewed-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add support for HP Pavilion dv5.
Since Intel-based models have an inverted x axis, while AMD-based models
have an inverted y axis, we introduce a new macro that special-cases axis
orientation based on two DMI entries: HP dv5 axis configuration is then
based on both the PRODUCT and BOARD name.
Signed-off-by: Giuseppe Bilotta <giuseppe.bilotta@gmail.com>
Cc: Eric Piel <Eric.Piel@tremplin-utc.net>
Cc: Pavel Machek <pavel@suse.cz>
Tested-by: Palatis Tseng <palatis@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sensors responding with 0x3B to WHO_AM_I only have one data register per
direction, thus returning a signed byte from the position which is
occupied by the MSB in sensors responding with 0x3A.
Since multiple sensors share the reply to WHO_AM_I, we rename the defines
to better indicate what they identify (family of single and double
precision sensors).
We support both kind of sensors by checking for the sensor type on init
and defining appropriate data-access routines and sensor limits (for the
joystick) depending on what we find.
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Giuseppe Bilotta <giuseppe.bilotta@gmail.com>
Acked-by: Eric Piel <Eric.Piel@tremplin-utc.net>
Cc: Pavel Machek <pavel@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This adds freefall handling to hp_accel driver. According to HP, it
should just work, without us having to set the chip up by hand.
hpfall.c is example .c program that parks the disk when accelerometer
detects free fall. It should work; for now, it uses fixed 20seconds
protection period.
Signed-off-by: Pavel Machek <pavel@suse.cz>
Cc: Thomas Renninger <trenn@suse.de>
Cc: Éric Piel <eric.piel@tremplin-utc.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Otherwise with INPUT=m, EEEPC_LAPTOP=y one gets
drivers/built-in.o: In function `input_sync':
eeepc-laptop.c:(.text+0x18ce51): undefined reference to `input_event'
drivers/built-in.o: In function `input_report_key':
eeepc-laptop.c:(.text+0x18ce73): undefined reference to `input_event'
drivers/built-in.o: In function `eeepc_hotk_check':
eeepc-laptop.c:(.text+0x18d05f): undefined reference to `input_allocate_device'
eeepc-laptop.c:(.text+0x18d10f): undefined reference to `input_register_device'
eeepc-laptop.c:(.text+0x18d131): undefined reference to `input_free_device'
drivers/built-in.o: In function `eeepc_backlight_exit':
eeepc-laptop.c:(.text+0x18d546): undefined reference to `input_unregister_device'
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Compilation of kprobes.c with CONFIG_PM unset is broken due to some broken
config dependncies. Fix that.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Reported-by: Ingo Molnar <mingo@elte.hu>
Tested-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Len Brown <lenb@kernel.org>
Acked-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In cgroup_kill_sb(), root is freed before sb is detached from the list, so
another sget() may find this sb and call cgroup_test_super(), which will
access the root that has been freed.
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Paul Menage <menage@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
YAMAMOTO-san noticed that task_dirty_inc doesn't seem to be called properly for
cases where set_page_dirty is not used to dirty a page (eg. mark_buffer_dirty).
Additionally, there is some inconsistency about when task_dirty_inc is
called. It is used for dirty balancing, however it even gets called for
__set_page_dirty_no_writeback.
So rather than increment it in a set_page_dirty wrapper, move it down to
exactly where the dirty page accounting stats are incremented.
Cc: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
As requested by Michael, add a missing check for valid flags in
timerfd_settime(), and make it return EINVAL in case some extra bits are
set.
Michael said:
If this is to be any use to userland apps that want to check flag
support (perhaps it is too late already), then the sooner we get it
into the kernel the better: 2.6.29 would be good; earlier stables as
well would be even better.
[akpm@linux-foundation.org: remove unused TFD_FLAGS_SET]
Acked-by: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Davide Libenzi <davidel@xmailserver.org>
Cc: <stable@kernel.org> [2.6.27.x, 2.6.28.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
My @suse.cz address will stop working some day, so put working one into
MAINTAINERS/CREDITS. It would be cool to get this to 2.6.29... it should
not really break anything.
Signed-off-by: Pavel Machek <pavel@ucw.cz>
Cc: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
