Remove the assumption that if the first page of a legacy ROM is mapped,
it'll all be mapped. This'll also stop people reading this code from
wondering if they're looking at a bug...
Signed-off-by: Rene Herman <rene.herman@gmail.com>
Signed-off-by: Martin Murray <murrayma@citi.umich.edu>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Andi Kleen <ak@suse.de>
Cc: Zachary Amsden <zach@vmware.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The VIA C7 is a 686 (with TSC) that supports MMX, SSE and SSE2, it also has
a cache line length of 64 according to
http://www.digit-life.com/articles2/cpu/rmma-via-c7.html. This patch sets
gcc to -march=686 and select s the correct cache shift.
Signed-off-by: Simon Arlott <simon@fire.lp0.eu>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Andi Kleen <ak@suse.de>
Cc: Dave Jones <davej@codemonkey.org.uk>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Eliminated the arch/i386/kernel/timers in 2.6.18, use clocksoures instead.
pit_latch_buggy was referred in timers/timer_tsc.c, and currently removed.
Therefore nobody refer it.
Until 2.6.17, MediaGX's TSC works correctly. after 2.6.18, warned "TSC
appears to be running slowly. Marking it as unstable". So marked unstable
TSC when CS55x0.
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andi Kleen <ak@suse.de>
Whether a region is below 1Mb is determined by its start rather than
its end.
This hunk got erroneously dropped from a previous patch.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
No need to use -traditional for processing asm in i386/kernel/
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Synchronize i386's smp_send_stop() with x86-64's in only try-locking
the call lock to prevent deadlocks when called from panic().
In both version, disable interrupts before clearing the CPU off the
online map to eliminate races with IRQ handlers inspecting this map.
Also in both versions, save/restore interrupts rather than disabling/
enabling them.
On x86-64, eliminate one function used here by folding it into its
single caller, convert to static, and rename for consistency with i386
(lkcd may like this).
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Avoid including asm/vsyscall32.h in virtually every source file.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Move inclusion of asm/fixmap.h to where it is really used rather than
where it may have been used long ago (requires a few other adjustments
to includes due to previous implicit dependencies).
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andi Kleen <ak@suse.de>
- make the page table contents printing PAE capable
- make sure the address stored in current->thread.cr2 is unmodified
from what was read from CR2
- don't call oops_may_print() multiple times, when one time suffices
- print pte even in highpte case, as long as the pte page isn't in
actually in high memory (which is specifically the case for all page
tables covering kernel space)
(Changes to v3: Use sizeof()*2 rather than the suggested sizeof()*4 for
printing width, use fixed 16-nibble width for PAE, and also apply the
max_low_pfn range check to the middle level lookup on PAE.)
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Remove clustered APIC mode. There's little point in the use of clustered APIC
mode, broadcasting is limited to within the cluster only, and chipsets have
bugs in this area as well. So default to physical APIC mode when the CPU
count is large, and default to logical APIC mode when the CPU count is 8 or
smaller.
(this patch only removes the use of genapic_cluster and cleans up the
resulting genapic.c file - removal of all remaining traces of clustered
mode will be done by another patch.)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Andi Kleen <ak@suse.de>
Cc: "Li, Shaohua" <shaohua.li@intel.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Fix a couple of inconsistencies/problems I found while reviewing the x86_64
genapic code (when I was chasing mysterious eth0 timeouts that would only
trigger if CPU_HOTPLUG is enabled):
- AMD systems defaulted to the slower flat-physical mode instead
of the flat-logical mode. The only restriction on AMD systems
is that they should not use clustered APIC mode.
- removed the CPU hotplug hacks, switching the default for small
systems back from phys-flat to logical-flat. The switching to logical
flat mode on small systems fixed sporadic ethernet driver timeouts i
was getting on a dual-core Athlon64 system:
NETDEV WATCHDOG: eth0: transmit timed out
eth0: Transmit timeout, status 0c 0005 c07f media 80.
eth0: Tx queue start entry 32 dirty entry 28.
eth0: Tx descriptor 0 is 0008a04a. (queue head)
eth0: Tx descriptor 1 is 0008a04a.
eth0: Tx descriptor 2 is 0008a04a.
eth0: Tx descriptor 3 is 0008a04a.
eth0: link up, 100Mbps, full-duplex, lpa 0xC5E1
- The use of '<= 8' was a bug by itself (the valid APIC ids
for logical flat mode go from 0 to 7, not 0 to 8). The new logic
is to use logical flat mode on both AMD and Intel systems, and
to only switch to physical mode when logical mode cannot be used.
If CPU hotplug is racy wrt. APIC shutdown then CPU hotplug needs
fixing, not the whole IRQ system be made inconsistent and slowed
down.
- minor cleanups: simplified some code constructs
build & booted on a couple of AMD and Intel SMP systems.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Andi Kleen <ak@suse.de>
Cc: "Li, Shaohua" <shaohua.li@intel.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
The Marvell IDE interface on my machine would hit a BUG_ON() in
lib/iomem.c because it was calling ata_pci_init_one() specifying just a
single port on the host, but that would actually end up trying to
initialize two ports, the second one with bogus information.
This fixes "ata_pci_init_one()" so that it actually passes down the
n_ports variable that it got from the low-level driver to the host
allocation routine ("ata_host_alloc_pinfo()"), which results in the ATA
layer actually having the correct port number information.
And in order to make it all work, I also needed to fix a few places that
had incorrectly hard-coded the fact that a host always had exactly two
ports (both ata_pci_init_bmdma() and ata_request_legacy_irqs() would
just always iterate over both ports).
Acked-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For backwards compatibility, call_platform_enable_wakeup() can return 0
instead of -EIO since we aren't guaranteed to have errno defined.
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a kvasprintf() function to complement kasprintf().
No in-tree users yet, but I have some coming up.
[akpm@linux-foundation.org: EXPORT it]
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Keir Fraser <keir@xensource.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch changes the docs and behaviour from "all states valid" to "no
states valid" if no .valid callback is assigned. Users of pm_ops that only
need mem sleep can assign pm_valid_only_mem without any overhead, others
will require more elaborate callbacks.
Now that all users of pm_ops have a .valid callback this is a safe thing to
do and prevents things from getting messy again as they were before.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Pavel Machek <pavel@ucw.cz>
Looks-okay-to: Rafael J. Wysocki <rjw@sisk.pl>
Cc: <linux-pm@lists.linux-foundation.org>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Almost all users of pm_ops only support mem sleep, don't check in .valid and
don't reject any others in .prepare so users can be confused if they check
/sys/power/state, especially when new states are added (these would then
result in s-t-r although they're supposed to be something different).
This patch implements a generic pm_valid_only_mem function that is then
exported for users and puts it to use in almost all existing pm_ops.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Cc: David Brownell <david-b@pacbell.net>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: linux-pm@lists.linux-foundation.org
Cc: Len Brown <lenb@kernel.org>
Acked-by: Russell King <rmk@arm.linux.org.uk>
Cc: Greg KH <greg@kroah.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch removes the firmware disk suspend mode which is the wrong approach,
it is supposed to be used for implementing firmware-based disk suspend but
cannot actually be used for that.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: <linux-pm@lists.linux-foundation.org>
Cc: David Brownell <david-b@pacbell.net>
Cc: Len Brown <lenb@kernel.org>
Acked-by: Russell King <rmk@arm.linux.org.uk>
Cc: Greg KH <greg@kroah.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch series cleans up some misconceptions about pm_ops. Some users of
the pm_ops structure attempt to use it to stop the user from entering suspend
to disk, this, however, is not possible since the user can always use
"shutdown" in /sys/power/disk and then the pm_ops are never invoked. Also,
platforms that don't support suspend to disk simply should not allow
configuring SOFTWARE_SUSPEND (read the help text on it, it only selects
suspend to disk and nothing else, all the other stuff depends on PM).
The pm_ops structure is actually intended to provide a way to enter
platform-defined sleep states (currently supported states are "standby" and
"mem" (suspend to ram)) and additionally (if SOFTWARE_SUSPEND is configured)
allows a platform to support a platform specific way to enter low-power mode
once everything has been saved to disk. This is currently only used by ACPI
(S4).
This patch:
The pm_ops.pm_disk_mode is used in totally bogus ways since nobody really
seems to understand what it actually does.
This patch clarifies the pm_disk_mode description.
It also removes all the arm and sh users that think they can veto suspend to
disk via pm_ops; not so since the user can always do echo shutdown >
/sys/power/disk, they need to find a better way involving Kconfig or such.
ACPI is the only user left with a non-zero pm_disk_mode.
The patch also sets the default mode to shutdown again, but when a new pm_ops
is registered its pm_disk_mode is selected as default, that way the default
stays for ACPI where it is apparently required.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Cc: David Brownell <david-b@pacbell.net>
Acked-by: Pavel Machek <pavel@ucw.cz>
Cc: <linux-pm@lists.linux-foundation.org>
Cc: Len Brown <lenb@kernel.org>
Acked-by: Russell King <rmk@arm.linux.org.uk>
Cc: Greg KH <greg@kroah.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We're getting lockdep warnings due to a post-2.6.21-rc7 bugfix.
The xattr_sem can never be taken in the manner described. Internal inodes
are protected by I_PRIVATE. Add the appropriate annotation.
Cc: <stable@kernel.org>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Today's print_symbol function dumps a kernel symbol with printk. This
patch extends the functionality of kallsyms.c so that the symbol lookup
function may be used without the printk. This is useful for modules that
want to dump symbols elsewhere, for example, to debugfs. I intend to use
the new function call in the GFS2 file system (which will be a separate
patch).
[akpm@linux-foundation.org: build fix]
[clameter@sgi.com: sprint_symbol should return length of string like sprintf]
Signed-off-by: Robert Peterson <rpeterso@redhat.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Cc: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Paulo Marques <pmarques@grupopie.com>
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When allocating local ports, do not allow a bind to a port
with a specific local address when a bind to that port with
a wildcard local address already exists.
Noticed by Linus.
Signed-off-by: David S. Miller <davem@davemloft.net>
I accidently applied an earlier version of Eric Dumazet's patch, from
March 21st. His version from March 30th didn't have these bugs, so
this just interdiffs to the correct patch.
Signed-off-by: David S. Miller <davem@davemloft.net>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6: (56 commits)
ieee1394: remove garbage from Kconfig
ieee1394: more help in Kconfig
ieee1394: ohci1394: Fix mistake in printk message.
ieee1394: ohci1394: remove unnecessary rcvPhyPkt bit flipping in LinkControl register
ieee1394: ohci1394: fix cosmetic problem in error logging
ieee1394: eth1394: send async streams at S100 on 1394b buses
ieee1394: eth1394: fix error path in module_init
ieee1394: eth1394: correct return codes in hard_start_xmit
ieee1394: eth1394: hard_start_xmit is called in atomic context
ieee1394: eth1394: some conditions are unlikely
ieee1394: eth1394: clean up fragment_overlap
ieee1394: eth1394: don't use alloc_etherdev
ieee1394: eth1394: omit useless set_mac_address callback
ieee1394: eth1394: CONFIG_INET is always defined
ieee1394: eth1394: allow MTU bigger than 1500
ieee1394: unexport highlevel_host_reset
ieee1394: eth1394: contain host reset
ieee1394: eth1394: shorter error messages
ieee1394: eth1394: correct a memset argument
ieee1394: eth1394: refactor .probe and .update
...
* 'for-linus' of master.kernel.org:/pub/scm/linux/kernel/git/jikos/hid: (21 commits)
USB HID: don't warn on idVendor == 0
USB HID: add 'quirks' module parameter
USB HID: add support for dynamically-created quirks
USB HID: clarify static quirk handling as squirks
USB HID: encapsulate quirk handling into hid-quirks.c
USB HID: EMS USBII device needs HID_QUIRK_MULTI_INPUT
HID: update copyright and authorship macro
HID: introduce proper zeroing of unused bits in output reports
USB HID: add support for WiseGroup MP-8800 Quad Joypad
USB HID: add FF support for Logitech Force 3D Pro Joystick
USB HID: numlock quirk for dell W7658 keyboard
USB HID: Logitech MX3000 keyboard needs report descriptor quirk
USB HID: extend quirk for Logitech S510 keyboard
USB HID: usbkbd/usbmouse - handle errors when registering devices
USB HID: add QUIRK_HIDDEV for Belkin Flip KVM
HID: enable dead keys on a belkin wireless keyboard
USB HID: Thustmaster firestorm dual power v1 support
USB HID: specify explicit size for hid_blacklist.quirks
USB HID: fix retry & reset logic
USB HID: consolidate vendor/product ids
...
* master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6: (21 commits)
[IPV4] SNMP: Support OutMcastPkts and OutBcastPkts
[IPV4] SNMP: Support InMcastPkts and InBcastPkts
[IPV4] SNMP: Support InTruncatedPkts
[IPV4] SNMP: Support InNoRoutes
[SNMP]: Add definitions for {In,Out}BcastPkts
[TCP] FRTO: RFC4138 allows Nagle override when new data must be sent
[TCP] FRTO: Delay skb available check until it's mandatory
[XFRM]: Restrict upper layer information by bundle.
[TCP]: Catch skb with S+L bugs earlier
[PATCH] INET : IPV4 UDP lookups converted to a 2 pass algo
[L2TP]: Add the ability to autoload a pppox protocol module.
[SKB]: Introduce skb_queue_walk_safe()
[AF_IUCV/IUCV]: smp_call_function deadlock
[IPV6]: Fix slab corruption running ip6sic
[TCP]: Update references in two old comments
[XFRM]: Export SPD info
[IPV6]: Track device renames in snmp6.
[SCTP]: Fix sctp_getsockopt_local_addrs_old() to use local storage.
[NET]: Remove NETIF_F_INTERNAL_STATS, default to internal stats.
[NETPOLL]: Remove CONFIG_NETPOLL_RX
...
* 'for-linus' of git://git.kernel.dk/data/git/linux-2.6-block:
[PATCH] elevator: elv_list_lock does not need irq disabling
[BLOCK] Don't pin lots of memory in mempools
cfq-iosched: speedup cic rb lookup
ll_rw_blk: add io_context private pointer
cfq-iosched: get rid of cfqq hash
cfq-iosched: tighten queue request overlap condition
cfq-iosched: improve sync vs async workloads
cfq-iosched: never allow an async queue idling
cfq-iosched: get rid of ->dispatch_slice
cfq-iosched: don't pass unused preemption variable around
cfq-iosched: get rid of ->cur_rr and ->cfq_list
cfq-iosched: slice offset should take ioprio into account
[PATCH] cfq-iosched: style cleanups and comments
cfq-iosched: sort IDLE queues into the rbtree
cfq-iosched: sort RT queues into the rbtree
[PATCH] cfq-iosched: speed up rbtree handling
cfq-iosched: rework the whole round-robin list concept
cfq-iosched: minor updates
cfq-iosched: development update
cfq-iosched: improve preemption for cooperating tasks
A transmitted IP multicast datagram should be counted as OutMcastPkts.
By the same token, a transmitted IP broadcast datagram should be
counted as OutBcastPkts.
Signed-off-by: Mitsuru Chinen <mitch@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
A received IP multicast datagram should be counted as InMcastPkts.
By the same token, a received IP broadcast datagram should be
counted as InBcastPkts.
Signed-off-by: Mitsuru Chinen <mitch@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
An IP datagram which is being discarded because the datagram frame
didn't carry enough data should be counted as InTruncatedPkts.
Signed-off-by: Mitsuru Chinen <mitch@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
An IP datagram which is being discarded because of no routes in the
forwarding path should be counted as InNoRoutes.
Signed-off-by: Mitsuru Chinen <mitch@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The updated IP-MIB RFC (RFC4293) specifys new objects, InBcastPkts
and OutBcastPkts. This adds definitions for them.
Signed-off-by: Mitsuru Chinen <mitch@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is a corner case where less than MSS sized new data thingie
is awaiting in the send queue. For F-RTO to work correctly, a
new data segment must be sent at certain point or F-RTO cannot
be used at all. RFC4138 allows overriding of Nagle at that
point.
Implementation uses frto_counter states 2 and 3 to distinguish
when Nagle override is needed.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
No new data is needed until the first ACK comes, so no need to check
for application limitedness until then.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
On MIPv6 usage, XFRM sub policy is enabled.
When main (IPsec) and sub (MIPv6) policy selectors have the same
address set but different upper layer information (i.e. protocol
number and its ports or type/code), multiple bundle should be created.
However, currently we have issue to use the same bundle created for
the first time with all flows covered by the case.
It is useful for the bundle to have the upper layer information
to be restructured correctly if it does not match with the flow.
1. Bundle was created by two policies
Selector from another policy is added to xfrm_dst.
If the flow does not match the selector, it goes to slow path to
restructure new bundle by single policy.
2. Bundle was created by one policy
Flow cache is added to xfrm_dst as originated one. If the flow does
not match the cache, it goes to slow path to try searching another
policy.
Signed-off-by: Masahide NAKAMURA <nakam@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
SACKED_ACKED and LOST are mutually exclusive with SACK, thus
having their sum larger than packets_out is bug with SACK.
Eventually these bugs trigger traps in the tcp_clean_rtx_queue
with SACK but it's much more informative to do this here.
Non-SACK TCP, however, could get more than packets_out duplicate
ACKs which each increment sacked_out, so it makes sense to do
this kind of limitting for non-SACK TCP but not for SACK enabled
one. Perhaps the author had the opposite in mind but did the
logic accidently wrong way around? Anyway, the sacked_out
incrementer code for non-SACK already deals this issue before
calling sync_left_out so this trapping can be done
unconditionally.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some people want to have many UDP sockets, binded to a single port but
many different addresses. We currently hash all those sockets into a
single chain. Processing of incoming packets is very expensive,
because the whole chain must be examined to find the best match.
I chose in this patch to hash UDP sockets with a hash function that
take into account both their port number and address : This has a
drawback because we need two lookups : one with a given address, one
with a wildcard (null) address.
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch allows a name "pppox-proto-nnn" to be used in modprobe.conf
to autoload a PPPoX protocol nnn.
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently we scale the mempool sizes depending on memory installed
in the machine, except for the bio pool itself which sits at a fixed
256 entry pre-allocation.
There's really no point in "optimizing" this OOM path, we just need
enough preallocated to make progress. A single unit is enough, lets
scale it down to 2 just to be on the safe side.
This patch saves ~150kb of pinned kernel memory on a 32-bit box.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>