Thomas Gleixner [Wed, 20 Feb 2008 22:57:30 +0000 (23:57 +0100)]
x86: fix vsyscall wreckage
based on a report from Arne Georg Gleditsch about user-space apps
misbehaving after toggling /proc/sys/kernel/vsyscall64, a review
of the code revealed that the "NOP patching" done there is
fundamentally unsafe for a number of reasons:
1) the patching code runs without synchronizing other CPUs
2) it inserts NOPs even if there is no clock source which provides vread
3) when the clock source changes to one without vread we run in
exactly the same problem as in #2
4) if nobody toggles the proc entry from 1 to 0 and to 1 again, then
the syscall is not patched out
as a result it is possible to break user-space via this patching.
The only safe thing for now is to remove the patching.
This code was broken since v2.6.21.
Reported-by: Arne Georg Gleditsch <arne.gleditsch@dolphinics.no> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Ingo Molnar [Thu, 21 Feb 2008 12:39:30 +0000 (13:39 +0100)]
x86: rename KERNEL_TEXT_SIZE => KERNEL_IMAGE_SIZE
The KERNEL_TEXT_SIZE constant was mis-named, as we not only map the kernel
text but data, bss and init sections as well.
That name led me on the wrong path with the KERNEL_TEXT_SIZE regression,
because i knew how big of _text_ my images have and i knew about the 40 MB
"text" limit so i wrongly thought to be on the safe side of the 40 MB limit
with my 29 MB of text, while the total image size was slightly above 40 MB.
40 MB is 42572719 bytes, so my vmlinux was just 1.5% above this limit :-/
So it happily crashed right in head_64.S, which - as we all know - is
the most debuggable code in the whole architecture ;-)
So increase the limit to allow an up to 128MB kernel image to be mapped.
(should anyone be that crazy or lazy)
We have a full 4K of pagetable (level2_kernel_pgt) allocated for these
mappings already, so there's no RAM overhead and the limit was rather
pointless and arbitrary.
H. Peter Anvin [Wed, 13 Feb 2008 19:16:46 +0000 (11:16 -0800)]
x86: handle BIOSes which terminate e820 with CF=1 and no SMAP
The proper way to terminate the e820 chain is with %ebx == 0 on the
last legitimate memory block. However, several BIOSes don't do that
and instead return error (CF = 1) when trying to read off the end of
the list. For this error return, %eax doesn't necessarily return the
SMAP signature -- correctly so, since %ah should contain an error code
in this case.
To deal with some particularly broken BIOSes, we clear the entire e820
chain if the SMAP signature is missing in the middle, indicating a
plain insane e820 implementation. However, we need to make the test
for CF = 1 before the SMAP check.
This fixes at least one HP laptop (nc6400) for which none of the
memory-probing methods (e820, e801, 88) functioned fully according to
spec.
Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
H. Peter Anvin [Thu, 14 Feb 2008 22:56:45 +0000 (14:56 -0800)]
x86: don't use P6_NOPs if compiling with CONFIG_X86_GENERIC
P6_NOPs are definitely not supported on some VIA CPUs, and possibly
(unverified) on AMD K7s. It is also the only thing that prevents a
686 kernel from running on Transmeta TM3x00/5x00 (Crusoe) series.
The performance benefit over generic NOPs is very small, so when
building for generic consumption, avoid using them.
Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
H. Peter Anvin [Thu, 14 Feb 2008 22:51:00 +0000 (14:51 -0800)]
x86: do not promote TM3x00/TM5x00 to i686-class
We have been promoting Transmeta TM3x00/TM5x00 chips to i686-class
based on the notion that they contain all the user-space visible
features of an i686-class chip. However, this is not actually true:
they lack the EA-taking long NOPs (0F 1F /0). Since this is a
userspace-visible incompatibility, downgrade these CPUs to the
manufacturer-defined i586 level.
Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
x86/early_ioremap: don't assume we're using swapper_pg_dir
At the early stages of boot, before the kernel pagetable has been
fully initialized, a Xen kernel will still be running off the
Xen-provided pagetables rather than swapper_pg_dir[]. Therefore,
readback cr3 to determine the base of the pagetable rather than
assuming swapper_pg_dir[].
static inline pmd_t * __init early_ioremap_pmd(unsigned long addr)
{
- pgd_t *pgd = &swapper_pg_dir[pgd_index(addr)];
+ /* Don't assume we're using swapper_pg_dir at this point */
+ pgd_t *base = __va(read_cr3());
+ pgd_t *pgd = &base[pgd_index(addr)];
pud_t *pud = pud_offset(pgd, addr);
pmd_t *pmd = pmd_offset(pud, addr);
Trying to analyze the problem, it seems on the guest side of lguest,
%cr3 has a different value from &swapper_pg-dir (which
is AFAIK fine on a pravirt guest):
Putting some debugging messages in early_ioremap_pmd:
Harvey Harrison [Wed, 13 Feb 2008 21:14:35 +0000 (13:14 -0800)]
lguest: include function prototypes
Added a declaration to asm-x86/lguest.h and moved the extern arrays there
as well. As an alternative to including asm/lguest.h directly, an
include could be put in linux/lguest.h
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Cc: "rusty@rustcorp.com.au" <rusty@rustcorp.com.au> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
David Brownell [Sun, 24 Feb 2008 19:03:42 +0000 (20:03 +0100)]
i2c: Make i2c_register_board_info() a NOP when CONFIG_I2C_BOARDINFO=n
Don't require platform code to be #ifdeffed according to whether
I2C is enabled or not ... if it's not enabled, let GCC compile out
all I2C device declarations. (Issue noted on an NSLU2 build that
didn't configure I2C.)
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Jean Delvare <khali@linux-fr.org>
Christian Krafft [Sun, 24 Feb 2008 19:03:42 +0000 (20:03 +0100)]
i2c-pca-isa: Add access check to legacy ioports
When probing i2c-pca-isa writes to legacy ioports, which crashes the kernel
if there is no device at that port.
This patch adds a check_legacy_ioport call, so probe fails gracefully
and thus prevents the oops.
Signed-off-by: Christian Krafft <krafft@de.ibm.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
Wolfram Sang [Sun, 24 Feb 2008 19:03:42 +0000 (20:03 +0100)]
i2c-pxa: Misc fixes
While working on the PCA9564-platform driver, I sometimes had a glimpse at the
pxa-driver. I found some suspicious places, and this patch contains my
suggestions. Note: They are not tested, due to no hardware.
[JD: Some more fixes.]
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de> Signed-off-by: Jean Delvare <khali@linux-fr.org> Tested-by: Mike Rapoport <mike@compulab.co.il> Tested-by: Eric Miao <ymiao3@marvell.com>
Jean Delvare [Sun, 24 Feb 2008 19:03:41 +0000 (20:03 +0100)]
ARM: OMAP: Release i2c_adapter after use (Siemens SX1)
Each call to i2c_get_adapter() must be followed by a call to
i2c_put_adapter() to release the grabbed reference. Otherwise the
reference count grows forever and the adapter can never be
unregistered.
Signed-off-by: Jean Delvare <khali@linux-fr.org> Acked-by: Vladimir Ananiev <vovan888@gmail.com> Acked-by: Tony Lindgren <tony@atomide.com>
Linus Torvalds [Sun, 24 Feb 2008 05:40:32 +0000 (21:40 -0800)]
Merge branch 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev
* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev:
libata-core: fix kernel-doc warning
sata_fsl: fix build with ATA_VERBOSE_DEBUG
[libata] ahci: AMD SB700/SB800 SATA support 64bit DMA
libata-pmp: clear hob for pmp register accesses
libata: automatically use DMADIR if drive/bridge requires it
power_state: get rid of write-only variable in SATA
pata_atiixp: Use 255 sector limit
Anton Vorontsov [Fri, 22 Feb 2008 16:54:25 +0000 (19:54 +0300)]
sata_fsl: fix build with ATA_VERBOSE_DEBUG
This patch fixes build and few warnings when ATA_VERBOSE_DEBUG
is defined:
CC drivers/ata/sata_fsl.o
drivers/ata/sata_fsl.c: In function ‘sata_fsl_fill_sg’:
drivers/ata/sata_fsl.c:338: warning: format ‘%x’ expects type ‘unsigned int’, but argument 3 has type ‘void *’
drivers/ata/sata_fsl.c:338: warning: format ‘%x’ expects type ‘unsigned int’, but argument 4 has type ‘struct prde *’
drivers/ata/sata_fsl.c: In function ‘sata_fsl_qc_issue’:
drivers/ata/sata_fsl.c:459: error: ‘csr_base’ undeclared (first use in this function)
drivers/ata/sata_fsl.c:459: error: (Each undeclared identifier is reported only once
drivers/ata/sata_fsl.c:459: error: for each function it appears in.)
drivers/ata/sata_fsl.c: In function ‘sata_fsl_freeze’:
drivers/ata/sata_fsl.c:525: error: ‘csr_base’ undeclared (first use in this function)
make[2]: *** [drivers/ata/sata_fsl.o] Error 1
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
Shane Huang [Fri, 22 Feb 2008 13:00:31 +0000 (05:00 -0800)]
[libata] ahci: AMD SB700/SB800 SATA support 64bit DMA
SB700 SATA controller can support 64 bit DMA, the previous commit badc2341579511a247f5993865aa68379e283c5c was added with
careless reference to SB600, which should be modified by this patch.
Signed-off-by: Shane Huang <shane.huang@amd.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
Mark Lord [Thu, 21 Feb 2008 20:52:25 +0000 (15:52 -0500)]
libata-pmp: clear hob for pmp register accesses
>> Mark Lord wrote:
>>> Tejun, I've added PMP to sata_mv, and am now trying to get it
>>> to work with a Marvell PM attached.
>>>
>>> And the behaviour I see is very bizarre.
>>>
>>> After hard+soft resets, the PM signature is found,
>>> and libata interrogates the PM registers.
>>>
>>> It successfully reads register 0, and then register 1.
>>> But all subsequent registers read out (incorrectly) as zeros.
...
This behavior has been confirmed by Marvell with a SATA analyzer.
The Marvell port-multiplier apparently likes to see clean HOB
information when accessing PMP registers.
Since sata_mv uses PIO shadow register access, this doesn't happen
automatically, as it might in a more purely FIS-based driver (eg. ahci).
One way to fix this is to flag these commands with ATA_TFLAG_LBA48,
forcing libata to write out the HOB fields with known (zero) values.
Signed-off-by: Saeed Bishara <saeed@marvell.com> Acked-by: Mark Lord <mlord@pobox.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
Tejun Heo [Thu, 21 Feb 2008 04:25:50 +0000 (13:25 +0900)]
libata: automatically use DMADIR if drive/bridge requires it
Back in 2.6.17-rc2, a libata module parameter was added for atapi_dmadir.
That's nice, but most SATA devices which need it will tell us about it
in their IDENTIFY PACKET response, as bit-15 of word-62 of the
returned data (as per ATA7, ATA8 specifications).
So for those which specify it, we should automatically use the DMADIR bit.
Otherwise, disc writing will fail by default on many SATA-ATAPI drives.
This patch adds ATA_DFLAG_DMADIR and make ata_dev_configure() set it
if atapi_dmadir is set or identify data indicates DMADIR is necessary.
atapi_xlat() is converted to check ATA_DFLAG_DMADIR before setting
DMADIR.
Original patch is from Mark Lord.
Signed-off-by: Tejun Heo <htejun@gmail.com> Cc: Mark Lord <mlord@pobox.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (37 commits)
[NETFILTER]: fix ebtable targets return
[IP_TUNNEL]: Don't limit the number of tunnels with generic name explicitly.
[NET]: Restore sanity wrt. print_mac().
[NEIGH]: Fix race between neighbor lookup and table's hash_rnd update.
[RTNL]: Validate hardware and broadcast address attribute for RTM_NEWLINK
tg3: ethtool phys_id default
[BNX2]: Update version to 1.7.4.
[BNX2]: Disable parallel detect on an HP blade.
[BNX2]: More 5706S link down workaround.
ssb: Fix support for PCI devices behind a SSB->PCI bridge
zd1211rw: fix sparse warnings
rtl818x: fix sparse warnings
ssb: Fix pcicore cardbus mode
ssb: Make the GPIO API reentrancy safe
ssb: Fix the GPIO API
ssb: Fix watchdog access for devices without a chipcommon
ssb: Fix serial console on new bcm47xx devices
ath5k: Fix build warnings on some 64-bit platforms.
WDEV, ath5k, don't return int from bool function
WDEV: ath5k, fix lock imbalance
...
CC [M] drivers/usb/host/u132-hcd.o
drivers/usb/host/u132-hcd.c: In function ‘u132_suspend’:
drivers/usb/host/u132-hcd.c:3224: error: expected expression before ‘int’
drivers/usb/host/u132-hcd.c:3225: error: ‘ports’ undeclared (first use in this function)
...
Joonwoo Park [Sun, 24 Feb 2008 04:22:27 +0000 (20:22 -0800)]
[NETFILTER]: fix ebtable targets return
The function ebt_do_table doesn't take NF_DROP as a verdict from the targets.
Signed-off-by: Joonwoo Park <joonwpark81@gmail.com> Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
Pavel Emelyanov [Sun, 24 Feb 2008 04:19:20 +0000 (20:19 -0800)]
[IP_TUNNEL]: Don't limit the number of tunnels with generic name explicitly.
Use the added dev_alloc_name() call to create tunnel device name,
rather than iterate in a hand-made loop with an artificial limit.
Thanks Patrick for noticing this.
[ The way this works is, when the device is actually registered,
the generic code noticed the '%' in the name and invokes
dev_alloc_name() to fully resolve the name. -DaveM ]
Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Pavel Emelyanov [Sun, 24 Feb 2008 03:57:02 +0000 (19:57 -0800)]
[NEIGH]: Fix race between neighbor lookup and table's hash_rnd update.
The neigh_hash_grow() may update the tbl->hash_rnd value, which
is used in all tbl->hash callbacks to calculate the hashval.
Two lookup routines may race with this, since they call the
->hash callback without the tbl->lock held. Since the hash_rnd
is changed with this lock write-locked moving the calls to ->hash
under this lock read-locked closes this gap.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Thomas Graf [Sun, 24 Feb 2008 03:54:36 +0000 (19:54 -0800)]
[RTNL]: Validate hardware and broadcast address attribute for RTM_NEWLINK
RTM_NEWLINK allows for already existing links to be modified. For this
purpose do_setlink() is called which expects address attributes with a
payload length of at least dev->addr_len. This patch adds the necessary
validation for the RTM_NEWLINK case.
The address length for links to be created is not checked for now as the
actual attribute length is used when copying the address to the netdevice
structure. It might make sense to report an error if less than addr_len
bytes are provided but enforcing this might break drivers trying to be
smart with not transmitting all zero addresses.
Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
When asked to blink LEDs the tg3 driver behaves when using:
ethtool -p ethX
The default value for data is zero, and other drivers interpret this
as blink forever (or at least a really long time). The tg3 driver
interprets this as blink once. All drivers should have the same
behaviour.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com> Acked-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Michael Chan [Sun, 24 Feb 2008 03:48:57 +0000 (19:48 -0800)]
[BNX2]: Disable parallel detect on an HP blade.
Because of some board issues, we need to disable parallel detect on
an HP blade. Without this patch, the link state can become stuck
when it goes into parallel detect mode.
Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Michael Chan [Sun, 24 Feb 2008 03:47:44 +0000 (19:47 -0800)]
[BNX2]: More 5706S link down workaround.
The previous patches to workaround the 5706S on an HP blade were not
sufficient. The link state still does not change properly in some
cases. This patch adds polling to make it completely reliable.
Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Linus Torvalds [Sun, 24 Feb 2008 02:05:03 +0000 (18:05 -0800)]
Add memory barrier semantics to wake_up() & co
Oleg Nesterov and others have pointed out that on some architectures,
the traditional sequence of
set_current_state(TASK_INTERRUPTIBLE);
if (CONDITION)
return;
schedule();
is racy wrt another CPU doing
CONDITION = 1;
wake_up_process(p);
because while set_current_state() has a memory barrier separating
setting of the TASK_INTERRUPTIBLE state from reading of the CONDITION
variable, there is no such memory barrier on the wakeup side.
Now, wake_up_process() does actually take a spinlock before it reads and
sets the task state on the waking side, and on x86 (and many other
architectures) that spinlock is in fact equivalent to a memory barrier,
but that is not generally guaranteed. The write that sets CONDITION
could move into the critical region protected by the runqueue spinlock.
However, adding a smp_wmb() to before the spinlock should now order the
writing of CONDITION wrt the lock itself, which in turn is ordered wrt
the accesses within the spinlock (which includes the reading of the old
state).
This should thus close the race (which probably has never been seen in
practice, but since smp_wmb() is a no-op on x86, it's not like this will
make anything worse either on the most common architecture where the
spinlock already gave the required protection).
Acked-by: Oleg Nesterov <oleg@tv-sign.ru> Acked-by: Dmitry Adamushko <dmitry.adamushko@gmail.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Nick Piggin <nickpiggin@yahoo.com.au> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Oleg Nesterov [Sat, 23 Feb 2008 21:03:29 +0000 (00:03 +0300)]
documentation: atomic_add_unless() doesn't imply mb() on failure
(sorry for being offtpoic, but while experts are here...)
A "typical" implementation of atomic_add_unless() can return 0 immediately
after the first atomic_read() (before doing cmpxchg). In that case it doesn't
provide any barrier semantics. See include/asm-ia64/atomic.h as an example.
We should either change the implementation, or fix the docs.
Li Zefan [Sat, 23 Feb 2008 23:24:13 +0000 (15:24 -0800)]
memcgroup: remove a useless VM_BUG_ON()
Remove this VM_BUG_ON(), as Balbir stated:
We used to have a for loop with !list_empty() as a termination condition
and VM_BUG_ON(!pc) is a spill over. With the new loop, VM_BUG_ON(!pc) does
not make sense.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Balbir Singh <balbir@in.ibm.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>
Li Zefan [Sat, 23 Feb 2008 23:24:09 +0000 (15:24 -0800)]
cgroup: clean up cgroup.h
- replace old name 'cont' with 'cgrp' (Paul Menage did this cleanup for
cgroup.c in commit bd89aabc6761de1c35b154fe6f914a445d301510)
- remove a duplicate declaration of cgroup_path()
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>
WARNING: vmlinux.o(.meminit.text+0x649):
Section mismatch in reference from the
function free_area_init_core() to the function .init.text:setup_usemap()
The function __meminit free_area_init_core() references
a function __init setup_usemap().
If free_area_init_core is only used by setup_usemap then
annotate free_area_init_core with a matching annotation.
The warning is covers this stack of functions in mm/page_alloc.c:
alloc_bootmem_node must be marked __init.
alloc_bootmem_node is used by setup_usemap, if !SPARSEMEM.
(usemap_size is only used by setup_usemap, if !SPARSEMEM.)
setup_usemap is only used by free_area_init_core.
free_area_init_core is only used by free_area_init_node.
hotadd_new_pgdat can not be an __init function, but:
It is compiled for MEMORY_HOTPLUG configurations only
MEMORY_HOTPLUG depends on SPARSEMEM || X86_64_ACPI_NUMA
X86_64_ACPI_NUMA depends on X86_64
ARCH_FLATMEM_ENABLE depends on X86_32
ARCH_DISCONTIGMEM_ENABLE depends on X86_32
So X86_64_ACPI_NUMA implies SPARSEMEM, right?
So we can mark the stack of functions __init for !SPARSEMEM, but we must mark
them __meminit for SPARSEMEM configurations. This is ok, because then the
calls to alloc_bootmem_node are also avoided.
Casey Schaufler [Sat, 23 Feb 2008 23:24:04 +0000 (15:24 -0800)]
Smack: update for file capabilities
Update the Smack LSM to allow the registration of the capability "module"
as a secondary LSM. Integrate the new hooks required for file based
capabilities.
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com> Cc: Serge Hallyn <serue@us.ibm.com> Cc: Stephen Smalley <sds@tycho.nsa.gov> Cc: Paul Moore <paul.moore@hp.com> Cc: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Srinivasa Ds [Sat, 23 Feb 2008 23:24:04 +0000 (15:24 -0800)]
kprobes: refuse kprobe insertion on add/sub_preempt_counter()
Kprobes makes use of preempt_disable(),preempt_enable_noresched() and these
functions inturn call add/sub_preempt_count(). So we need to refuse user from
inserting probe in to these functions.
This patch disallows user from probing add/sub_preempt_count().
Signed-off-by: Srinivasa DS <srinivasa@in.ibm.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andi Kleen [Sat, 23 Feb 2008 23:24:02 +0000 (15:24 -0800)]
cgroup memory controller: document huge memory/cache overhead in Kconfig
Document huge memory/cache overhead of memory controller in Kconfig
I was a little surprised that 2.6.25-rc* increased struct page for the
memory controller. At least on many x86-64 machines it will not fit into a
single cache line now anymore and also costs considerable amounts of RAM.
At earlier review I remembered asking for a external data structure for
this.
It's also quite unobvious that a innocent looking Kconfig option with a
single line Kconfig description has such a negative effect.
This patch attempts to document these disadvantages at least so that users
configuring their kernel can make a informed decision.
Signed-off-by: Andi Kleen <ak@suse.de> Cc: Balbir Singh <balbir@in.ibm.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>
When running "make htmldocs" I'm seeing some non-fatal perl errors caused
by trying to parse the callback function definitions in blk-core.c.
The errors are "Use of uninitialized value in concatenation (.)..."
in combination with:
Warning(linux-2.6.25-rc2/block/blk-core.c:1877): No description found for parameter ''
The function pointers are defined without a * i.e.
int (drv_callback)(struct request *)
The compiler is happy with them, but kernel-doc isn't.
This patch teaches create_parameterlist in kernel-doc to parse this type of
function pointer definition, but is it the right way to fix the problem ?
The problem only seems to occur in blk-core.c.
However with the patch applied, kernel-doc finds the correct parameter
description for the callback in blk_end_request_callback, which is doesn't
normally.
I thought it would be a bit odd to change to code to use the more normal
form of function pointers just to get the documentation to work, so I fixed
kernel-doc instead - even though this is teaching it to understand code
that might go away (The comment for blk_end_request_callback says that it
should not be used and will removed at some point).
Signed-off-by: Richard Kennedy <richard@rsk.demon.co.uk> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Thomas Gleixner [Sat, 23 Feb 2008 23:23:57 +0000 (15:23 -0800)]
futex: runtime enable pi and robust functionality
Not all architectures implement futex_atomic_cmpxchg_inatomic(). The default
implementation returns -ENOSYS, which is currently not handled inside of the
futex guts.
Futex PI calls and robust list exits with a held futex result in an endless
loop in the futex code on architectures which have no support.
Fixing up every place where futex_atomic_cmpxchg_inatomic() is called would
add a fair amount of extra if/else constructs to the already complex code. It
is also not possible to disable the robust feature before user space tries to
register robust lists.
Compile time disabling is not a good idea either, as there are already
architectures with runtime detection of futex_atomic_cmpxchg_inatomic support.
Detect the functionality at runtime instead by calling
cmpxchg_futex_value_locked() with a NULL pointer from the futex initialization
code. This is guaranteed to fail, but the call of
futex_atomic_cmpxchg_inatomic() happens with pagefaults disabled.
On architectures, which use the asm-generic implementation or have a runtime
CPU feature detection, a -ENOSYS return value disables the PI/robust features.
On architectures with a working implementation the call returns -EFAULT and
the PI/robust features are enabled.
The relevant syscalls return -ENOSYS and the robust list exit code is blocked,
when the detection fails.
Fixes http://lkml.org/lkml/2008/2/11/149
Originally reported by: Lennart Buytenhek
Thomas Gleixner [Sat, 23 Feb 2008 23:23:55 +0000 (15:23 -0800)]
futex: fix init order
When the futex init code fails to initialize the futex pseudo file system it
returns early without initializing the hash queues. Should the boot succeed
then a futex syscall which tries to enqueue a waiter on the hashqueue will
crash due to the unitilialized plist heads.
Jean Delvare [Sat, 23 Feb 2008 23:23:55 +0000 (15:23 -0800)]
dmi: prevent linked list corruption
Adding the same item to a given linked list more than once is guaranteed
to break and corrupt the list. This is however what we do in dmi_scan
since commit 79da4721117fcf188b4b007b775738a530f574da ("x86: fix DMI out
of memory problems").
Given that there is absolutely no interest in saving empty OEM strings
anyway, I propose the simple and efficient fix below: we discard the empty
OEM strings altogether.
Signed-off-by: Jean Delvare <khali@linux-fr.org> Acked-by: Parag Warudkar <parag.warudkar@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Matt Domsch <Matt_Domsch@dell.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sergio Luis [Sat, 23 Feb 2008 23:23:53 +0000 (15:23 -0800)]
drivers/video/uvesafb.c: fix section mismatch warning in param_set_scroll()
Fix following warnings:
WARNING: drivers/video/built-in.o(.text+0x7c64a): Section mismatch in reference from the function param_set_scroll() to the variable .devinit.data:ypan
WARNING: drivers/video/built-in.o(.text+0x7c65d): Section mismatch in reference from the function param_set_scroll() to the variable .devinit.data:ypan
WARNING: drivers/video/built-in.o(.text+0x7c679): Section mismatch in reference from the function param_set_scroll() to the variable .devinit.data:ypan
WARNING: drivers/video/built-in.o(.text+0x7c699): Section mismatch in reference from the function param_set_scroll() to the variable .devinit.data:ypan
WARNING: drivers/video/built-in.o(.text+0x7c69f): Section mismatch in reference from the function param_set_scroll() to the variable .devinit.data:ypan
WARNING: drivers/built-in.o(.text+0xa3676): Section mismatch in reference from the function param_set_scroll() to the variable .devinit.data:ypan
WARNING: drivers/built-in.o(.text+0xa3689): Section mismatch in reference from the function param_set_scroll() to the variable .devinit.data:ypan
WARNING: drivers/built-in.o(.text+0xa36a5): Section mismatch in reference from the function param_set_scroll() to the variable .devinit.data:ypan
WARNING: drivers/built-in.o(.text+0xa36c5): Section mismatch in reference from the function param_set_scroll() to the variable .devinit.data:ypan
WARNING: drivers/built-in.o(.text+0xa36cb): Section mismatch in reference from the function param_set_scroll() to the variable .devinit.data:ypan
WARNING: vmlinux.o(.text+0x4a079a): Section mismatch in reference from the function param_set_scroll() to the variable .devinit.data:ypan
WARNING: vmlinux.o(.text+0x4a07ad): Section mismatch in reference from the function param_set_scroll() to the variable .devinit.data:ypan
WARNING: vmlinux.o(.text+0x4a07c9): Section mismatch in reference from the function param_set_scroll() to the variable .devinit.data:ypan
WARNING: vmlinux.o(.text+0x4a07e9): Section mismatch in reference from the function param_set_scroll() to the variable .devinit.data:ypan
WARNING: vmlinux.o(.text+0x4a07ef): Section mismatch in reference from the function param_set_scroll() to the variable .devinit.data:ypan
Remove __devinitdata annotation from the variable ypan.
Signed-off-by: Sergio Luis <sergio@larces.uece.br> Cc: Michal Januszewski <spock@gentoo.org> Cc: "Antonino A. Daplas" <adaplas@pol.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Eugene Teo [Sat, 23 Feb 2008 23:23:52 +0000 (15:23 -0800)]
proc: add RLIMIT_RTTIME to /proc/<pid>/limits
RLIMIT_RTTIME was introduced to allow the user to set a runtime timeout on
real-time tasks: http://lkml.org/lkml/2007/12/18/218. This patch updates
/proc/<pid>/limits with the new rlimit.
Signed-off-by: Eugene Teo <eugeneteo@kernel.sg> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge include/linux/efs_fs{_i,_dir}.h into fs/efs/efs.h. efs_vh.h remains
there because this is the IRIX volume header and shouldn't really be
handled by efs but by the partitioning code. efs_sb.h remains there for
now because it's exported to userspace. Of course this wrong and aboot
should have a copy of it's own, but I'll leave that to a separate patch to
avoid any contention.
Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There have been posts to nbd-general mailing list about problems with
cfq and nbd also.
2) nbd performs about 10% better (the last time I tested) with deadline
vs. cfq (the overhead of cfq doesn't provide much advantage to nbd [not
being a real disk], and you end up going through the I/O scheduler on
the nbd server anyway, so it makes sense that deadline is better with
nbd)
Signed-off-by: Paul Clements <paul.clements@steeleye.com> Cc: Jens Axboe <jens.axboe@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jeff Dike [Sat, 23 Feb 2008 23:23:49 +0000 (15:23 -0800)]
uml: fix FP register corruption
Commit ee3d9bd4de1ed93d2a7ee41c331ed30a1c7b8acd ("uml: simplify SIGSEGV
handling"), while greatly simplifying the kernel SIGSEGV handler that
runs in the process address space, introduced a bug which corrupts FP
state in the process.
Previously, the SIGSEGV handler called the sigreturn system call by hand - it
couldn't return through the restorer provided to it because that could try to
call the libc restorer which likely wouldn't exist in the process address
space. So, it blocked off some signals, including SIGUSR1, on entry to the
SIGSEGV handler, queued a SIGUSR1 to itself, and invoked sigreturn. The
SIGUSR1 was delivered, and was visible to the UML kernel after sigreturn
finished.
The commit eliminated the signal masking and the call to sigreturn. The
handler simply hits itself with a SIGTRAP to let the UML kernel know that it
is finished. UML then restores the process registers, which effectively
longjmps the process out of the signal handler, skipping sigreturn's restoring
of register state and the signal mask.
The bug is that the host apparently sets used_fp to 0 when it saves the
process FP state in the sigcontext on the process signal stack. Thus, when
the process is longjmped out of the handler, its FP state is corrupt because
it wasn't saved on the context switch to the UML kernel.
This manifested itself as sleep hanging. For some reason, sleep uses floating
point in order to calculate the sleep interval. When a page fault corrupts
its FP state, it is faked into essentially sleeping forever.
This patch saves the FP state before entering the SIGSEGV handler and restores
it afterwards.
Signed-off-by: Jeff Dike <jdike@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In commit 1aa351a308d2c3ddb92b6cc45083fc54271d0010 ("uml: tidy helper
code") the arguments of helper_wait() were changed. The adaptation of
harddog_user.c was forgotten, so this errors occur:
/arch/um/drivers/harddog_user.c: In function 'start_watchdog':
/arch/um/drivers/harddog_user.c:82: error: too many arguments to function 'helper_wait'
/arch/um/drivers/harddog_user.c:89: error: too many arguments to function 'helper_wait'
Signed-off-by: Johann Felix Soden <johfel@users.sourceforge.net> Signed-off-by: Jeff Dike <jdike@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jeff Dike [Sat, 23 Feb 2008 23:23:48 +0000 (15:23 -0800)]
uml: remove unused sigcontext accessors
The macros which extract registers from a struct sigcontext are no longer
needed and can be removed. They are starting not to build anyway, given the
removal of the 'e' and 'r' from register names during the x86 merge.
Cc: Jiri Olsa <olsajiri@gmail.com> Signed-off-by: Jeff Dike <jdike@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jean Delvare [Sat, 23 Feb 2008 23:23:46 +0000 (15:23 -0800)]
dmi: don't save the same device twice
Now that we gather on-board devices from both DMI types 10 and 41, there is
a possibility that we list the same device twice. In order to not confuse
drivers, and also to save memory, make sure that we do not add duplicate
devices to the dmi_devices list.
Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Wim Van Sebroeck <wim@iguana.be> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Brownell [Sat, 23 Feb 2008 23:23:44 +0000 (15:23 -0800)]
rtc-cmos: display HPET emulation mode
For the "cmos" RTC, have /proc/driver/rtc say whether HPET based IRQ
emulation is in effect. Given the problems we've had with this particular
hardware maldesign (and the fact that most BIOS code seems not to provide
the IRQ routing needed to use the saner HPET modes), this should help
troubleshooting.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Alessandro Zummo <a.zummo@towertech.it> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Michael Buesch [Sat, 23 Feb 2008 23:23:42 +0000 (15:23 -0800)]
hwrng: remove Michael as HWRNG maintainer
It turns out that I rewrote the HWRNG core once to make it pluggable, but
I'm not a crypto-expert at all. So I'm certainly the wrong person for
being a maintainer of the HWRNG core. Let's orphan it.
Signed-off-by: Michael Buesch <mb@bu3sch.de> Cc: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Current implementation of cpuset track N_HIGH_MEMORY instead N_MEMORY.
(N_MEMORY doesn't exist in current implementation)
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: Paul Jackson <pj@sgi.com> Cc: Christoph Lameter <clameter@sgi.com> Cc: Paul Menage <menage@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ned Forrester [Sat, 23 Feb 2008 23:23:40 +0000 (15:23 -0800)]
spi: pxa2xx_spi clock polarity fix
Fixes a sequencing bug in spi driver pxa2xx_spi.c in which the chip select
for a transfer may be asserted before the clock polarity is set on the
interface. As a result of this bug, the clock signal may have the wrong
polarity at transfer start, so it may need to make an extra half transition
before the intended clock/data signals begin. (This probably means all
transfers are one bit out of sequence.)
This only occurs on the first transfer following a change in clock polarity
in systems using more than one more than one such polarity. The fix
assures that the clock mode is properly set before asserting chip select.
This bug was introduced in a patch merged on 2006/12/10, kernel 2.6.20.
The patch defines an additional bit in: include/asm-arm/arch-pxa/regs-ssp.h
for 2.6.25 and newer kernels but this addition must be made in:
include/asm-arm/arch-pxa/pxa-regs.h for kernels between 2.6.20 and 2.6.24,
inclusive
Signed-off-by: Ned Forrester <nforrester@whoi.edu> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Russell King <rmk@arm.linux.org.uk> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Atsushi Nemoto [Sat, 23 Feb 2008 23:23:39 +0000 (15:23 -0800)]
atmel_spi: fix clock polarity
The atmel_spi driver does not initialize clock polarity correctly (except for
at91rm9200 CS0 channel) in some case.
The atmel_spi driver uses gpio-controlled chipselect. OTOH spi clock signal
is controlled by CSRn.CPOL bit, but this register controls clock signal
correctly only in 'real transfer' duration. At the time of cs_activate()
call, CSRn.CPOL will be initialized correctly, but the controller do not know
which channel is to be used next, so clock signal will stay at the inactive
state of last transfer. If clock polarity of new transfer and last transfer
was differ, new transfer will start with wrong clock signal state.
For example, if you started SPI MODE 2 or 3 transfer after SPI MODE 0 or 1
transfer, the clock signal state at the assertion of chipselect will be low.
Of course this will violates SPI transfer.
This patch is short term solution for this problem. It makes all CSRn.CPOL
match for the transfer before activating chipselect. For longer term, the
best fix might be to let NPCS0 stay selected permanently in MR and overwrite
CSR0 with to the new slave's settings before asserting CS.
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Acked-by: Haavard Skinnemoen <hskinnemoen@atmel.com> Cc: David Brownell <david-b@pacbell.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We should only return IRQ_HANDLED when we actually found something to
handle. This is important since the USART interrupt handler may be
shared with the timer interrupt on some chips.
Pointed-out-by: michael <trimarchi@gandalf.sssup.it> Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Rientjes [Sat, 23 Feb 2008 23:23:34 +0000 (15:23 -0800)]
sparc: fix build
Fix build failure on sparc:
In file included from include/linux/mm.h:39,
from include/linux/memcontrol.h:24,
from include/linux/swap.h:8,
from include/linux/suspend.h:7,
from init/do_mounts.c:6:
include/asm/pgtable.h:344: warning: parameter names (without
types) in function declaration
include/asm/pgtable.h:345: warning: parameter names (without
types) in function declaration
include/asm/pgtable.h:346: error: expected '=', ',', ';', 'asm' or
'__attribute__' before '___f___swp_entry'
viro sayeth:
I've run allmodconfig builds on a bunch of target, FWIW (essentially the
same patch). Note that these includes are recent addition caused by added
inline function that had since then become a define. So while I agree with
your comments in general, in _this_ case it's pretty safe.
Cc: Adrian Bunk <bunk@kernel.org> Cc: Robert Reif <reif@earthlink.net> Signed-off-by: David Rientjes <rientjes@google.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Serge E. Hallyn [Sat, 23 Feb 2008 23:23:33 +0000 (15:23 -0800)]
file capabilities: simplify signal check
Simplify the uid equivalence check in cap_task_kill(). Anyone can kill a
process owned by the same uid.
Without this patch wireshark is reported to fail.
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com> Signed-off-by: Andrew G. Morgan <morgan@kernel.org> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andy Whitcroft [Sat, 23 Feb 2008 23:23:32 +0000 (15:23 -0800)]
hugetlb: ensure we do not reference a surplus page after handing it to buddy
When we free a page via free_huge_page and we detect that we are in surplus
the page will be returned to the buddy. After this we no longer own the page.
However at the end free_huge_page we clear out our mapping pointer from
page private. Even where the page is not a surplus we free the page to
the hugepage pool, drop the pool locks and then clear page private. In
either case the page may have been reallocated. BAD.
Make sure we clear out page private before we free the page.
Signed-off-by: Andy Whitcroft <apw@shadowen.org> Acked-by: Adam Litke <agl@us.ibm.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hans Rosenfeld [Sat, 23 Feb 2008 23:23:31 +0000 (15:23 -0800)]
/proc/pid/pagemap: fix PM_SPECIAL macro
There seems to be a bug in the PM_SPECIAL macro for /proc/pid/pagemap. I
think masking out those other bits makes more sense then setting all those
mask bits.
Signed-off-by: Hans Rosenfeld <Hans.Rosenfeld@amd.com> Acked-by: Matt Mackall <mpm@selenic.com> Cc: Dave Hansen <haveblue@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Miklos Szeredi [Sat, 23 Feb 2008 23:23:27 +0000 (15:23 -0800)]
fuse: fix permission checking
I added a nasty local variable shadowing bug to fuse in 2.6.24, with the
result, that the 'default_permissions' mount option is basically ignored.
How did this happen?
- old err declaration in inner scope
- new err getting declared in outer scope
- 'return err' from inner scope getting removed
- old declaration not being noticed
-Wshadow would have saved us, but it doesn't seem practical for
the kernel :(
WANG Cong [Sat, 23 Feb 2008 23:23:26 +0000 (15:23 -0800)]
arch/um/kernel/mem.c: fix a shadowed variable
Fix a shadowed variable in arch/um/kernel/mem.c, since there is a global
variable has the same name.
Cc: Jeff Dike <jdike@linux.intel.com> Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jeff Dike [Sat, 23 Feb 2008 23:23:24 +0000 (15:23 -0800)]
UML: update defconfig
Update defconfig.
Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Jeff Dike <jdike@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
projects / linux-2.6 / log