According to the CBEA, the SPU dsisr is not updated for class 0
exceptions.
spu_stopped() is testing the dsisr that was passed to it from the class
0 exception handler, so we return a false positive here.
This patch cleans up the interrupt handler and erroneous tests in
spu_stopped. It also removes the fields from the csa since it is not
needed to process class 0 events.
Signed-off-by: Luke Browning <lukebrowning@us.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
PCI: fixup write combine comment in pci_mmap_resource
x86: PAT export resource_wc in pci sysfs
x86, pci-dma.c: don't always add __GFP_NORETRY to gfp
suspend-vs-iommu: prevent suspend if we could not resume
x86: pci-dma.c: use __GFP_NO_OOM instead of __GFP_NORETRY
pci, x86: add workaround for bug in ASUS A7V600 BIOS (rev 1005)
PCI: use dev_to_node in pci_call_probe
PCI: Correct last two HP entries in the bfsort whitelist
* git://git.kernel.org/pub/scm/linux/kernel/git/kyle/parisc-2.6:
parisc: update my email address
parisc: fix miscompilation of ip_fast_csum with gcc >= 4.3
parisc: fix off by one in setup_sigcontext32
parisc: export empty_zero_page
parisc: export copy_user_page_asm
parisc: move head.S to head.text section
Revert "parisc: fix trivial section name warnings"
ip_fast_csum needs an asm "memory" clobber, otherwise the aggressive
optimizations in gcc-4.3 cause it to be miscompiled.
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
tcp: Revert 'process defer accept as established' changes.
ipv6: Fix duplicate initialization of rawv6_prot.destroy
bnx2x: Updating the Maintainer
net: Eliminate flush_scheduled_work() calls while RTNL is held.
drivers/net/r6040.c: correct bad use of round_jiffies()
fec_mpc52xx: MPC52xx_MESSAGES_DEFAULT: 2nd NETIF_MSG_IFDOWN => IFUP
ipg: fix receivemode IPG_RM_RECEIVEMULTICAST{,HASH} in ipg_nic_set_multicast_list()
netfilter: nf_conntrack: fix ctnetlink related crash in nf_nat_setup_info()
netfilter: Make nflog quiet when no one listen in userspace.
ipv6: Fail with appropriate error code when setting not-applicable sockopt.
ipv6: Check IPV6_MULTICAST_LOOP option value.
ipv6: Check the hop limit setting in ancillary data.
ipv6 route: Fix route lifetime in netlink message.
ipv6 mcast: Check address family of gf_group in getsockopt(MS_FILTER).
dccp: Bug in initial acknowledgment number assignment
dccp ccid-3: X truncated due to type conversion
dccp ccid-3: TFRC reverse-lookup Bug-Fix
dccp ccid-2: Bug-Fix - Ack Vectors need to be ignored on request sockets
dccp: Fix sparse warnings
dccp ccid-3: Bug-Fix - Zero RTT is possible
We need this at least for huge page detection for now, because powerpc
needs the vm_area_struct to be able to determine whether a virtual address
is referring to a huge page (its pmd_huge() doesn't work).
It might also come in handy for some of the other users.
Signed-off-by: Dave Hansen <dave@linux.vnet.ibm.com>
Acked-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add support for the next generation of HP Smart Array SAS/SATA
controllers. Shipping date is late Fall 2008.
Bump the driver version to 3.6.20 to reflect the new hardware support from
patch 1 of this set.
Signed-off-by: Mike Miller <mike.miller@hp.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Move the forward-declaration of struct mm_struct a little way up
proc_fs.h. This fixes a bunch of "'struct mm_struct' declared inside
parameter list" warnings with CONFIG_PROC_FS=n
Signed-off-by: Ben Nizette <bn@niasdigital.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add ext2_find_{first,next}_bit(), which are needed for ext4. They're
derived out of the ext2_find_next_zero_bit found in the same file.
Compile tested with crosstools
[Reworked to preserve all symmetry with ext2_find_{first,next}_zero_bit()]
This fixes http://bugzilla.kernel.org/show_bug.cgi?id=10393
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This reverts two changesets, ec3c0982a2
("[TCP]: TCP_DEFER_ACCEPT updates - process as established") and
the follow-on bug fix 9ae27e0adb
("tcp: Fix slab corruption with ipv6 and tcp6fuzz").
This change causes several problems, first reported by Ingo Molnar
as a distcc-over-loopback regression where connections were getting
stuck.
Ilpo Järvinen first spotted the locking problems. The new function
added by this code, tcp_defer_accept_check(), only has the
child socket locked, yet it is modifying state of the parent
listening socket.
Fixing that is non-trivial at best, because we can't simply just grab
the parent listening socket lock at this point, because it would
create an ABBA deadlock. The normal ordering is parent listening
socket --> child socket, but this code path would require the
reverse lock ordering.
Next is a problem noticed by Vitaliy Gusev, he noted:
----------------------------------------
>--- a/net/ipv4/tcp_timer.c
>+++ b/net/ipv4/tcp_timer.c
>@@ -481,6 +481,11 @@ static void tcp_keepalive_timer (unsigned long data)
> goto death;
> }
>
>+ if (tp->defer_tcp_accept.request && sk->sk_state == TCP_ESTABLISHED) {
>+ tcp_send_active_reset(sk, GFP_ATOMIC);
>+ goto death;
Here socket sk is not attached to listening socket's request queue. tcp_done()
will not call inet_csk_destroy_sock() (and tcp_v4_destroy_sock() which should
release this sk) as socket is not DEAD. Therefore socket sk will be lost for
freeing.
----------------------------------------
Finally, Alexey Kuznetsov argues that there might not even be any
real value or advantage to these new semantics even if we fix all
of the bugs:
----------------------------------------
Hiding from accept() sockets with only out-of-order data only
is the only thing which is impossible with old approach. Is this really
so valuable? My opinion: no, this is nothing but a new loophole
to consume memory without control.
----------------------------------------
So revert this thing for now.
Signed-off-by: David S. Miller <davem@davemloft.net>
Macros like Fld() or FShft used in regs-lcd.h are defined in bitfield.h, but
the latter is not included.
Also fix one whitespace issue while being there.
Signed-off-by: Antonio Ospite <ao2@openezx.org>
Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org>
Acked-by: Eric Miao <eric.miao@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
* 'core/iter-div' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
always_inline timespec_add_ns
add an inlined version of iter_div_u64_rem
common implementation of iterative div/mod
timespec_add_ns is used from the x86-64 vdso, which cannot call out to
other kernel code. Make sure that timespec_add_ns is always inlined
(and only uses always_inlined functions) to make sure there are no
unexpected calls.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
iter_div_u64_rem is used in the x86-64 vdso, which cannot call other
kernel code. For this case, provide the always_inlined version,
__iter_div_u64_rem.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
We have a few instances of the open-coded iterative div/mod loop, used
when we don't expcet the dividend to be much bigger than the divisor.
Unfortunately modern gcc's have the tendency to strength "reduce" this
into a full mod operation, which isn't necessarily any faster, and
even if it were, doesn't exist if gcc implements it in libgcc.
The workaround is to put a dummy asm statement in the loop to prevent
gcc from performing the transformation.
This patch creates a single implementation of this loop, and uses it
to replace the open-coded versions I know about.
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Segher Boessenkool <segher@kernel.crashing.org>
Cc: Christian Kujau <lists@nerdbynature.de>
Cc: Robert Hancock <hancockr@shaw.ca>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
For the ranges with IORESOURCE_PREFETCH, export a new resource_wc interface in
pci /sysfs along with resource (which is uncached).
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch adds a proper prototype for acpi_processor_tstate_has_changed()
in include/acpi/processor.h
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
cpuidle and acpi driver interaction bug with the way cpuidle_register_driver()
is called. Due to this bug, there will be oops on
AC<->DC on some systems, where they support C-states in one DC and not in AC.
The current code does
ON BOOT:
Look at CST and other C-state info to see whether more than C1 is
supported. If it is, then acpi processor_idle does a
cpuidle_register_driver() call, which internally enables the device.
ON CST change notification (AC<->DC) and on suspend-resume:
acpi driver temporarily disables device, updates the device with
any new C-states, and reenables the device.
The problem is is on boot, there are no C2, C3 states supported and we skip
the register. Later on AC<->DC, we may get a CST notification and we try
to reevaluate CST and enabled the device, without actually registering it.
This causes breakage as we try to create /sys fs sub directory, without the
parent directory which is created at register time.
Thanks to Sanjeev for reporting the problem here.
http://bugzilla.kernel.org/show_bug.cgi?id=10394
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
This patch fixes following section mismatch:
WARNING: arch/powerpc/sysdev/built-in.o(.text+0x11d8): Section mismatch in
reference from the function qe_reset() to the function
.init.text:cpm_muram_init()
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
* 'kvm-updates-2.6.26' of git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm:
KVM: MMU: Fix is_empty_shadow_page() check
KVM: MMU: Fix printk() format string
KVM: IOAPIC: only set remote_irr if interrupt was injected
KVM: MMU: reschedule during shadow teardown
KVM: VMX: Clear CR4.VMXE in hardware_disable
KVM: migrate PIT timer
KVM: ppc: Report bad GFNs
KVM: ppc: Use a read lock around MMU operations, and release it on error
KVM: ppc: Remove unmatched kunmap() call
KVM: ppc: add lwzx/stwz emulation
KVM: ppc: Remove duplicate function
KVM: s390: Fix race condition in kvm_s390_handle_wait
KVM: s390: Send program check on access error
KVM: s390: fix interrupt delivery
KVM: s390: handle machine checks when guest is running
KVM: s390: fix locking order problem in enable_sie
KVM: s390: use yield instead of schedule to implement diag 0x44
KVM: x86 emulator: fix hypercall return value on AMD
KVM: ia64: fix zero extending for mmio ld1/2/4 emulation in KVM
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (42 commits)
net: Fix routing tables with id > 255 for legacy software
sky2: Hold RTNL while calling dev_close()
s2io iomem annotations
atl1: fix suspend regression
qeth: start dev queue after tx drop error
qeth: Prepare-function to call s390dbf was wrong
qeth: reduce number of kernel messages
qeth: Use ccw_device_get_id().
qeth: layer 3 Oops in ip event handler
virtio: use callback on empty in virtio_net
virtio: virtio_net free transmit skbs in a timer
virtio: Fix typo in virtio_net_hdr comments
virtio_net: Fix skb->csum_start computation
ehea: set mac address fix
sfc: Recover from RX queue flush failure
add missing lance_* exports
ixgbe: fix typo
forcedeth: msi interrupts
ipsec: pfkey should ignore events when no listeners
pppoe: Unshare skb before anything else
...
Most legacy software do not like tables > 255 as rtm_table is u8
so tb_id is sent &0xff and it is possible to mismatch for example
table 510 with table 254 (main).
This patch introduces RT_TABLE_COMPAT=252 so the code uses it if
tb_id > 255. It makes such old applications happy, new
ones are still able to use RTA_TABLE to get a proper table id.
Signed-off-by: Krzysztof Piotr Oledzki <ole@ans.pl>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Wei Yongjun noticed that we may call reqsk_free on request sock objects where
the opt fields may not be initialized, fix it by introducing inet_reqsk_alloc
where we initialize ->opt to NULL and set ->pktopts to NULL in
inet6_reqsk_alloc.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
- The tcp_unhash() method in /include/net/tcp.h is no more needed, as the
unhash method in tcp_prot structure is now inet_unhash (instead of
tcp_unhash in the
past); see tcp_prot structure in net/ipv4/tcp_ipv4.c.
- So, this patch removes tcp_unhash() declaration from include/net/tcp.h
Signed-off-by: Rami Rosen <ramirose@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
I forgot to remove the ide_etrax100 chipset type when removing the
ETRAX_IDE driver.
Reported-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
This is very trivial patch. We're transitioning to the cpm_muram_*
calls. That's it.
Less trivial changes:
- BD_SC_* defines were defined in the cpm.h and qe.h, so to avoid redefines
we remove BD_SC from the qe.h and use cpm.h along with cpm_muram_*
prototypes;
- qe_muram_dump was unused and thus removed;
- added some code to the cpm_common.c to support legacy QE bindings
(data-only node name).
- For convenience, define qe_* calls to cpm_*. So drivers need not to be
changed.
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
This is needed to access QE GPIOs via Linux GPIO API.
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Acked-By: Timur Tabi <timur@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
- split and export __par_io_config_pin() out of par_io_config_pin(), so we
could use the prefixed version with GPIO LIB API;
- rename struct port_regs to qe_pio_regs, and place it into qe.h;
- rename #define NUM_OF_PINS to QE_PIO_PINS, and place it into qe.h.
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Acked-By: Timur Tabi <timur@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
This patch adds a function to the qe_lib to setup QE USB clocks routing.
To setup clocks safely, cmxgcr register needs locking, so I just reused
ucc_lock since it was used only to protect cmxgcr.
The idea behind placing clocks routing functions into the qe_lib is that
later we'll hopefully switch to the generic Linux Clock API, thus, for
example, FHCI driver may be used for QE and CPM chips without nasty #ifdefs.
This patch also fixes QE_USB_RESTART_TX command definition in the qe.h.
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Acked-By: Timur Tabi <timur@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
GTM stands for General-purpose Timers Module and able to generate
timer{1,2,3,4} interrupts. These timers are used by the drivers that
need time precise interrupts (like for USB transactions scheduling for
the Freescale USB Host controller as found in some QE and CPM chips),
or these timers could be used as wakeup events from the CPU deep-sleep
mode.
Things unimplemented:
1. Cascaded (32 bit) timers (1-2, 3-4).
This is straightforward to implement when needed, two timers should
be marked as "requested" and configured as appropriate.
2. Super-cascaded (64 bit) timers (1-2-3-4).
This is also straightforward to implement when needed, all timers
should be marked as "requested" and configured as appropriate.
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
All the maintained platforms are now in arch/powerpc, so the old
arch/ppc stuff can now go away.
Acked-by: Adrian Bunk <bunk@kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Becky Bruce <becky.bruce@freescale.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Jochen Friedrich <jochen@scram.de>
Acked-by: John Linn <john.linn@xilinx.com>
Acked-by: Jon Loeliger <jdl@freescale.com>
Acked-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Acked-by: Olof Johansson <olof@lixom.net>
Acked-by: Peter Korsgaard <jacmet@sunsite.dk>
Acked-by: Scott Wood <scottwood@freescale.com>
Acked-by: Sean MacLennan <smaclennan@pikatech.com>
Acked-by: Segher Boessenkool <segher@kernel.crashing.org>
Acked-by: Stefan Roese <sr@denx.de>
Acked-by: Stephen Neuendorffer <stephen.neuendorffer@xilinx.com>
Acked-by: Wolfgang Denk <wd@denx.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
schedule() has the special "TASK_INTERRUPTIBLE && signal_pending()" case,
this allows us to do
current->state = TASK_INTERRUPTIBLE;
schedule();
without fear to sleep with pending signal.
However, the code like
current->state = TASK_KILLABLE;
schedule();
is not right, schedule() doesn't take TASK_WAKEKILL into account. This means
that mutex_lock_killable(), wait_for_completion_killable(), down_killable(),
schedule_timeout_killable() can miss SIGKILL (and btw the second SIGKILL has
no effect).
Introduce the new helper, signal_pending_state(), and change schedule() to
use it. Hopefully it will have more users, that is why the task's state is
passed separately.
Note this "__TASK_STOPPED | __TASK_TRACED" check in signal_pending_state().
This is needed to preserve the current behaviour (ptrace_notify). I hope
this check will be removed soon, but this (afaics good) change needs the
separate discussion.
The fast path is "(state & (INTERRUPTIBLE | WAKEKILL)) + signal_pending(p)",
basically the same that schedule() does now. However, this patch of course
bloats schedule().
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
__ctl_load/__ctl_store are called with either an array of unsigned long or
a single unsigned long value. Add an address operator to the "m"/"=m"
contraints to make them work for unsigned long arguments as well.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband:
IB/core: Remove IB_DEVICE_SEND_W_INV capability flag
IB/umem: Avoid sign problems when demoting npages to integer
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/blackfin-2.6:
Blackfin serial driver: fix up tty core set_ldisc API change breakage bug
Blackfin arch: protect only the SPI bus controller with CONFIG_SPI_BFIN
Blackfin arch: fixup warnings with the new cplb saved values
Blackfin Serial Driver: Clean up BF54x macro in blackfin UART driver.
This patch fixes a typo in the name of a config variable.
Reported-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Reviewed-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc:
[POWERPC] ehea: Remove dependency on MEMORY_HOTPLUG
[POWERPC] Make walk_memory_resource available with MEMORY_HOTPLUG=n
[POWERPC] Use dev_set_name in pci_64.c
[POWERPC] Fix incorrect enabling of VMX when building signal or user context
[POWERPC] boot/Makefile CONFIG_ variable fixes
Minor source code cleanup of page flags in mm/page_alloc.c.
Move the definition of the groups of bits to page-flags.h.
The purpose of this clean up is that the next patch will
conditionally add a page flag to the groups. Doing that
in a header file is cleaner than adding #ifdefs to the
C code.
Signed-off-by: Russ Anderson <rja@sgi.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In 2.6.26, we added some support for send with invalidate work
requests, including a device capability flag to indicate whether a
device supports such requests. However, the support was incomplete:
the completion structure was not extended with a field for the key
contained in incoming send with invalidate requests.
Full support for memory management extensions (send with invalidate,
local invalidate, fast register through a send queue, etc) is planned
for 2.6.27. Since send with invalidate is not very useful by itself,
just remove the IB_DEVICE_SEND_W_INV bit before the 2.6.26 final
release; we will add an IB_DEVICE_MEM_MGT_EXTENSIONS bit in 2.6.27,
which makes things simpler for applications, since they will not have
quite as confusing an array of fine-grained bits to check.
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Since commit 4cb3cee03d the code generated
for the in_beXX() and out_beXX() mmio functions has been sub-optimal.
The out_leXX() family of functions are created with the macro
DEF_MMIO_OUT_LE() while the out_beXX() family are created with
DEF_MMIO_OUT_BE(). In what was perhaps a bit too much macro use, both of
these macros are in turn created via the macro DEF_MMIO_OUT().
For the LE versions, eventually they boil down to an asm that will look
something like this:
asm("sync; stwbrx %1,0,%2" : "=m" (*addr) : "r" (val), "r" (addr));
The issue is that the "stwbrx" instruction only comes in an indexed, or
'x', version, in which the address is represented by the sum of two
registers (the "0,%2"). Unfortunately, gcc doesn't have a constraint for
an indexed memory reference. The "m" constraint allows both indexed and
offset, i.e. register plus constant, memory references and there is no
"stwbr" version for offset references. "m" also allows updating addresses
and there is no 'u' version of "stwbrx" like there is with "stwux".
The unused first operand to the asm is just to tell gcc that *addr is an
output of the asm. The address used is passed in a single register via the
third asm operand, and the index register is just hard coded as 0. This
means gcc is forced to put the address in a single register and can't use
index addressing, e.g. if one has the data in register 9, a base address in
register 3 and an index in register 4, gcc must emit code like "add 11,4,3;
stwbrx 9,0,11" instead of just "stwbrx 9,4,3". This costs an extra add
instruction and another register.
For gcc 4.0 and older, there doesn't appear to be anything that can be
done. But for 4.1 and newer, there is a 'Z' constraint. It does not allow
"updating" addresses, but does allow both indexed and offset addresses.
However, the only allowed constant offset is 0. We can then use the
undocumented 'y' operand modifier, which causes gcc to convert "0(reg)"
into the equivilient "0,reg" format that can be used with stwbrx.
This brings us the to problem with the BE version. In this case, the "stw"
instruction does have both indexed and non-indexed versions. The final asm
ends up looking like this:
asm("sync; stw%U0%X0 %1,%0" : "=m" (*addr) : "r" (val), "r" (addr));
The undocumented codes "%U0" and "%0X" will generate a 'u' if the memory
reference should be an auto-updating one, and an 'x' if the memory
reference is indexed, respectively. The third operand is unused, it's just
there because asm the code is reused from the LE version. However, gcc
does not know this, and generates unnecessary code to stick addr in a
register! To use the example from the LE version, gcc will generate "add
11,4,3; stwx 9,4,3". It is able to use the indexed address "4,3" for the
"stwx", but still thinks it needs to put 4+3 into register 11, which will
never be used.
This also ends up happening a lot for the offset addressing mode, where
common code like this: out_be32(&device_registers->some_register, data);
uses an instruction like "stw 9, 42(3)", where register 3 has the pointer
device_registers and 42 is the offset of some_register in that structure.
gcc will be forced to generate the unnecessary instruction "addi 11, 3, 42"
to put the address into a single (unused) register.
The in_* versions end up having these exact same problems as well.
Signed-off-by: Trent Piepho <tpiepho@freescale.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Andreas Schwab <schwab@suse.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Make sure CONFIG_TASK_SIZE does not overlap CONFIG_KERNEL_START
This could happen when overriding settings to get 1GB lowmem, and would lead
to userland mysteriousely hanging.
This setting is only used by PPC32.
Signed-off-by: Rune Torgersen <runet@innovsys.com>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
