kzfree() is a wrapper for kfree() that additionally zeroes the underlying
memory before releasing it to the slab allocator.
Currently there is code which memset()s the memory region of an object
before releasing it back to the slab allocator to make sure
security-sensitive data are really zeroed out after use.
These callsites can then just use kzfree() which saves some code, makes
users greppable and allows for a stupid destructor that isn't necessarily
aware of the actual object size.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Matt Mackall <mpm@selenic.com>
Acked-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
oprofile for MN10300 seems to have been broken by the advent of the new
tracing framework.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
arch/ia64/xen/xen_pv_ops.c:156: error: xen_init_ops causes a section type conflict
arch/ia64/xen/xen_pv_ops.c:340: error: xen_iosapic_ops causes a section type conflict
Signed-off-by: Tony Luck <tony.luck@intel.com>
This patch fixes xen related Kconfigs and add default config
file for ia64 xen domU.
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Tony Luck <aegl@agluck-desktop.(none)>
The second call to cpu_clear() is redundant, as we've already removed
the CPU from cpu_online_map before calling migrate_platform_irqs().
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Tony Luck <aegl@agluck-desktop.(none)>
This reverts commit e7b140365b.
Commit e7b14036 removes the targetted disabled CPU from the
cpu_online_map after calls to migrate_platform_irqs and fixup_irqs.
Paul McKenney states that the reasoning behind the patch was to
prevent irq handlers from running on CPUs marked offline because:
RCU happily ignores CPUs that don't have their bits set in
cpu_online_map, so if there are RCU read-side critical sections
in the irq handlers being run, RCU will ignore them. If the
other CPUs were running, they might sequence through the RCU
state machine, which could result in data structures being
yanked out from under those irq handlers, which in turn could
result in oopses or worse.
Unfortunately, both ia64 functions above look at cpu_online_map to find
a new CPU to migrate interrupts onto. This means we can potentially
migrate an interrupt off ourself back to... ourself. Uh oh.
This causes an oops when we finally try to process pending interrupts on
the CPU we want to disable. The oops results from calling __do_IRQ with
a NULL pt_regs:
Unable to handle kernel NULL pointer dereference (address 0000000000000040)
Call Trace:
[<a000000100016930>] show_stack+0x50/0xa0
sp=e0000009c922fa00 bsp=e0000009c92214d0
[<a0000001000171a0>] show_regs+0x820/0x860
sp=e0000009c922fbd0 bsp=e0000009c9221478
[<a00000010003c700>] die+0x1a0/0x2e0
sp=e0000009c922fbd0 bsp=e0000009c9221438
[<a0000001006e92f0>] ia64_do_page_fault+0x950/0xa80
sp=e0000009c922fbd0 bsp=e0000009c92213d8
[<a00000010000c7a0>] ia64_native_leave_kernel+0x0/0x270
sp=e0000009c922fc60 bsp=e0000009c92213d8
[<a0000001000ecdb0>] profile_tick+0xd0/0x1c0
sp=e0000009c922fe30 bsp=e0000009c9221398
[<a00000010003bb90>] timer_interrupt+0x170/0x3e0
sp=e0000009c922fe30 bsp=e0000009c9221330
[<a00000010013a800>] handle_IRQ_event+0x80/0x120
sp=e0000009c922fe30 bsp=e0000009c92212f8
[<a00000010013aa00>] __do_IRQ+0x160/0x4a0
sp=e0000009c922fe30 bsp=e0000009c9221290
[<a000000100012290>] ia64_process_pending_intr+0x2b0/0x360
sp=e0000009c922fe30 bsp=e0000009c9221208
[<a0000001000112d0>] fixup_irqs+0xf0/0x2a0
sp=e0000009c922fe30 bsp=e0000009c92211a8
[<a00000010005bd80>] __cpu_disable+0x140/0x240
sp=e0000009c922fe30 bsp=e0000009c9221168
[<a0000001006c5870>] take_cpu_down+0x50/0xa0
sp=e0000009c922fe30 bsp=e0000009c9221148
[<a000000100122610>] stop_cpu+0xd0/0x200
sp=e0000009c922fe30 bsp=e0000009c92210f0
[<a0000001000e0440>] kthread+0xc0/0x140
sp=e0000009c922fe30 bsp=e0000009c92210c8
[<a000000100014ab0>] kernel_thread_helper+0xd0/0x100
sp=e0000009c922fe30 bsp=e0000009c92210a0
[<a00000010000a4c0>] start_kernel_thread+0x20/0x40
sp=e0000009c922fe30 bsp=e0000009c92210a0
I don't like this revert because it is fragile. ia64 is getting lucky
because we seem to only ever process timer interrupts in this path, but
if we ever race with an IPI here, we definitely use RCU and have the
potential of hitting an oops that Paul describes above.
Patching ia64's timer_interrupt() to check for NULL pt_regs is
insufficient though, as we still hit the above oops.
As a short term solution, I do think that this revert is the right
answer. The revert hold up under repeated testing (24+ hour test runs)
with this setup:
- 8-way rx6600
- randomly toggling CPU online/offline state every 2 seconds
- running CPU exercisers, memory hog, disk exercisers, and
network stressors
- average system load around ~160
In the long term, we really need to figure out why we set pt_regs = NULL
in ia64_process_pending_intr(). If it turns out that it is unnecessary
to do so, then we could safely re-introduce e7b14036 (along with some
other logic to be smarter about migrating interrupts).
One final note: x86 also removes the disabled CPU from cpu_online_map
and then re-enables interrupts for 1ms, presumably to handle any pending
interrupts:
arch/x86/kernel/irq_32.c (and irq_64.c):
cpu_disable_common:
[remove cpu from cpu_online_map]
fixup_irqs():
for_each_irq:
[break CPU affinities]
local_irq_enable();
mdelay(1);
local_irq_disable();
So they are doing implicitly what ia64 is doing explicitly.
Signed-off-by: Alex Chiang <achiang@hp.com>
Signed-off-by: Tony Luck <aegl@agluck-desktop.(none)>
BTE_MAX_XFER is wrong. It is one greater than the number of cache
lines the BTE is actually able to transfer. If you request a transfer
of exactly BTE_MAX_XFER size, you trip a very cryptic BUG_ON() which
should certainly be made more clear.
This patch fixes that constant and also cleans up the BUG_ON()s in
arch/ia64/sn/kernel/bte.c to test one condition per line.
Signed-off-by: Robin Holt <holt@sgi.com>
Signed-off-by: Tony Luck <aegl@agluck-desktop.(none)>
ia64 only defines __early_pfn_to_nid() for SPARSEMEM && NUMA configurations,
so the recent:
commit: f2dbcfa738
mm: clean up for early_pfn_to_nid()
ends up with some link problems for certain configuration files.
Fix arch/ia64/Kconfig to only define HAVE_ARCH_EARLY_PFN_TO_NID in the
cases where we do provide this function.
Signed-off-by: Tony Luck <tony.luck@intel.com>
This reverts commit d2859751cd.
This commit caused regression. We'll try to fix use of new
vmap API for next release.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
This reverts commit 95f8e302c0.
This commit caused regression. We'll try to fix use of new
vmap API for next release.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Felix Blyakher <felixb@sgi.com>
* '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>
