"Smarter retry of costly-order allocations" patch series change behaver of
do_try_to_free_pages(). But unfortunately ret variable type was
unchanged.
Thus an overflow is possible.
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: Nishanth Aravamudan <nacc@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Changed the call to find_e820_area_size to pass u64 instead of unsigned long.
Signed-off-by: Kevin Winchester <kjwinchester@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Alessandro Suardi reported:
> Recently upgraded my FC6 desktop to Fedora 9; with the
> latest nautilus RPM updates my VNC session went nuts
> with nautilus pegging the CPU for everything that breathed.
>
> I now reverted to an earlier nautilus package, but during
> the peak CPU period my kernel spat this:
>
> [314185.623294] ------------[ cut here ]------------
> [314185.623414] WARNING: at kernel/lockdep.c:2658 check_flags+0x4c/0x128()
> [314185.623514] Modules linked in: iptable_filter ip_tables x_tables
> sunrpc ipv6 fuse snd_via82xx snd_ac97_codec ac97_bus snd_mpu401_uart
> snd_rawmidi via686a hwmon parport_pc sg parport uhci_hcd ehci_hcd
> [314185.623924] Pid: 12314, comm: nautilus Not tainted 2.6.26-rc5-git2 #4
> [314185.624021] [<c0115b95>] warn_on_slowpath+0x41/0x7b
> [314185.624021] [<c010de70>] ? do_page_fault+0x2c1/0x5fd
> [314185.624021] [<c0128396>] ? up_read+0x16/0x28
> [314185.624021] [<c010de70>] ? do_page_fault+0x2c1/0x5fd
> [314185.624021] [<c012fa33>] ? __lock_acquire+0xbb4/0xbc3
> [314185.624021] [<c012d0a0>] check_flags+0x4c/0x128
> [314185.624021] [<c012fa73>] lock_acquire+0x31/0x7d
> [314185.624021] [<c0128cf6>] __atomic_notifier_call_chain+0x30/0x80
> [314185.624021] [<c0128cc6>] ? __atomic_notifier_call_chain+0x0/0x80
> [314185.624021] [<c0128d52>] atomic_notifier_call_chain+0xc/0xe
> [314185.624021] [<c0128d81>] notify_die+0x2d/0x2f
> [314185.624021] [<c01043b0>] do_int3+0x1f/0x4d
> [314185.624021] [<c02f2d3b>] int3+0x27/0x2c
> [314185.624021] =======================
> [314185.624021] ---[ end trace 1923f65a2d7bb246 ]---
> [314185.624021] possible reason: unannotated irqs-off.
> [314185.624021] irq event stamp: 488879
> [314185.624021] hardirqs last enabled at (488879): [<c0102d67>]
> restore_nocheck+0x12/0x15
> [314185.624021] hardirqs last disabled at (488878): [<c0102dca>]
> work_resched+0x19/0x30
> [314185.624021] softirqs last enabled at (488876): [<c011a1ba>]
> __do_softirq+0xa6/0xac
> [314185.624021] softirqs last disabled at (488865): [<c010476e>]
> do_softirq+0x57/0xa6
>
> I didn't seem to find it with some googling, so here it is.
>
> I was incidentally ltracing that process to try and find out
> what was gulping down that much CPU (sorry, no idea
> whether ltrace and the WARNING happened at the same
> time or which came first) and:
Yeah, this is extremely likely to be the source of the warning.
The warning should be harmless, however.
> Box is my trusty noname K7-800, 512MB RAM; if there's
> anything else useful I might be able to provide, just ask.
It would be interesting to see where the int3 comes from. Too bad,
lockdep doesn't provide the register dump. The stacktrace also doesn't
go further than the int3(), I wonder if this int3 came from userspace?
The ltrace readme says "software breakpoints, like gdb", so I guess
this is the case. Yep, seems like it.
This looks relevant:
| commit fb1dac909d
| Author: Peter Zijlstra <a.p.zijlstra@chello.nl>
| Date: Wed Jan 16 09:51:59 2008 +0100
|
| lockdep: more hardirq annotations for notify_die()
I'm attaching a similarly-looking patch for this case (DO_VM86_ERROR),
though I suspect it might be missing for the other cases
(DO_ERROR/DO_ERROR_INFO) as well.
Reported-by: Alessandro Suardi <alessandro.suardi@gmail.com>
Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Fix an incompatible pointer type warning on x86_64 compilations.
early_memtest() is passing a u64* to find_e820_area_size() which is expecting
an unsigned long. Change t_start and t_size to unsigned long as those are
also 64-bit types on x88_64.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This reverts commit 6e908947b4.
Németh Márton reported:
| there is a problem in 2.6.26-rc3 which was not there in case of
| 2.6.25: the CPU wakes up ~90,000 times per sec instead of ~60 per sec.
|
| I also "git bisected" the problem, the result is:
|
| 6e908947b4 is first bad commit
| commit 6e908947b4
| Author: Ingo Molnar <mingo@elte.hu>
| Date: Fri Mar 21 14:32:36 2008 +0100
|
| x86: fix ioapic bug again
the original problem is fixed by Maciej W. Rozycki in the tip/x86/apic
branch (confirmed by Márton), but those changes are too intrusive for
v2.6.26 so we'll go for the less intrusive (repeated) revert now.
Reported-and-bisected-by: Németh Márton <nm127@freemail.hu>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
On Mon, May 19, 2008 at 04:10:02PM -0700, Linus Torvalds wrote:
> It also causes these warnings on 32-bit PAE:
>
> AS arch/x86/kernel/head_32.o
> arch/x86/kernel/head_32.S: Assembler messages:
> arch/x86/kernel/head_32.S:225: Warning: left operand is a bignum; integer 0 assumed
> arch/x86/kernel/head_32.S:609: Warning: left operand is a bignum; integer 0 assumed
>
> and I do not see why (the end result seems to be identical).
Fix head_32.S gcc bignum warnings when CONFIG_PAE=y.
arch/x86/kernel/head_32.S: Assembler messages:
arch/x86/kernel/head_32.S:225: Warning: left operand is a bignum; integer 0 assumed
arch/x86/kernel/head_32.S:609: Warning: left operand is a bignum; integer 0 assumed
The assembler was stumbling over the 64-bit constant 0x100000000 in the
KPMDS #define.
Testing: a cmp(1) on head_32.o before and after shows the binary is unchanged.
Signed-off-by: Joe Korty <joe.korty@ccur.com
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Theodore Tso <tytso@mit.edu>
Cc: Gabriel C <nix.or.die@googlemail.com>
Cc: Keith Packard <keithp@keithp.com>
Cc: "Pallipadi Venkatesh" <venkatesh.pallipadi@intel.com>
Cc: Eric Anholt <eric@anholt.net>
Cc: "Siddha Suresh B" <suresh.b.siddha@intel.com>
Cc: bugme-daemon@bugzilla.kernel.org
Cc: airlied@linux.ie
Cc: "Barnes Jesse" <jesse.barnes@intel.com>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Page faults in kernel address space between PAGE_OFFSET up to
VMALLOC_START should not try to map as vmalloc.
Fix rarely endless page faults inside mount_block_root for root
filesystem at boot time.
All 32bit kernels up to 2.6.25 can fail into this hole.
I can not present this under native linux kernel. I see, that the 64bit
has fixed the problem. I copied the same lines into 32bit part.
Recorded debugs are from coLinux kernel 2.6.22.18 (virtualisation):
http://www.henrynestler.com/colinux/testing/pfn-check-0.7.3/20080410-antinx/bug16-recursive-page-fault-endless.txt
The physicaly memory was trimmed down to 192MB to better catch the bug.
More memory gets the bug more rarely.
Details, how every x86 32bit system can fail:
Start from "mount_block_root",
http://lxr.linux.no/linux/init/do_mounts.c#L297
There the variable "fs_names" got one memory page with 4096 bytes.
Variable "p" walks through the existing file system types. The first
string is no problem.
But, with the second loop in mount_block_root the offset of "p" is not
at beginning of page, the offset is for example +9, if "reiserfs" is the
first in list.
Than calls do_mount_root, and lands in sys_mount.
Remember: Variable "type_page" contains now "fs_type+9" and not contains
a full page.
The sys_mount copies 4096 bytes with function "exact_copy_from_user()":
http://lxr.linux.no/linux/fs/namespace.c#L1540
Mostly exist pages after the buffer "fs_names+4096+9" and the page fault
handler was not called. No problem.
In the case, if the page after "fs_names+4096" is not mapped, the page
fault handler was called from http://lxr.linux.no/linux/fs/namespace.c#L1320
The do_page_fault gots an address 0xc03b4000.
It's kernel address, address >= TASK_SIZE, but not from vmalloc! It's
from "__getname()" alias "kmem_cache_alloc".
The "error_code" is 0. "vmalloc_fault" will be call:
http://lxr.linux.no/linux/arch/i386/mm/fault.c#L332
"vmalloc_fault" tryed to find the physical page for a non existing
virtual memory area. The macro "pte_present" in vmalloc_fault()
got a next page fault for 0xc0000ed0 at:
http://lxr.linux.no/linux/arch/i386/mm/fault.c#L282
No PTE exist for such virtual address. The page fault handler was trying
to sync the physical page for the PTE lockup.
This called vmalloc_fault() again for address 0xc000000, and that also
was not existing. The endless began...
In normal case the cpu would still loop with disabled interrrupts. Under
coLinux this was catched by a stack overflow inside printk debugs.
Signed-off-by: Henry Nestler <henry.nestler@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
As we may run relay_reserve from interrupt context we must always disable
IRQs. This is because a call to relay_reserve may expose previously written
data to use space.
Updated new message code and an old but related comment.
Signed-off-by: Carl Henrik Lunde <chlunde@ping.uio.no>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This implements a few changes on top of the recent kobjsize() refactoring
introduced by commit 6cfd53fc03.
As Christoph points out:
virt_to_head_page cannot return NULL. virt_to_page also
does not return NULL. pfn_valid() needs to be used to
figure out if a page is valid. Otherwise the page struct
reference that was returned may have PageReserved() set
to indicate that it is not a valid page.
As discussed further in the thread, virt_addr_valid() is the preferable
way to validate the object pointer in this case. In addition to fixing
up the reserved page case, it also has the benefit of encapsulating the
hack introduced by commit 4016a1390d on
the impacted platforms, allowing us to get rid of the extra checking in
kobjsize() for the platforms that don't perform this type of bizarre
memory_end abuse (every nommu platform that isn't blackfin). If blackfin
decides to get in line with every other platform and use PageReserved
for the DMA pages in question, kobjsize() will also continue to work
fine.
It also turns out that compound_order() will give us back 0-order for
non-head pages, so we can get rid of the PageCompound check and just
use compound_order() directly. Clean that up while we're at it.
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Reviewed-by: Christoph Lameter <clameter@sgi.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch fixes a compile failure in 2.6.26-rc5-git5.
The variable is expected to be called ofdev.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* '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
Kumar Gala <galak@kernel.crashing.org> wrote:
We have a case in powerpc in which we want to link some library
routines with all module objects. The routines are intended for
handling out-of-line function call register save/restore so having
them as EXPORT_SYMBOL() is counter productive (we do also need to
link the same "library" code into the kernel).
Without this patch a powerpc build would error out and fail
to build modules with the added register save/restore module.
There were two obvious solutions:
1) To link the .o file before the modpost stage
2) To ignore the symbols in modpost
Option 1) was ruled out because we do not have any separate
linking stage for single file modules.
This patch implements option 2 - and do so only for powerpc.
The symbols we ignore are all undefined symbols named:
_restgpr_*, _savegpr_*, _rest32gpr_*, _save32gpr_*
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
(overflow means weight >= 2^32 here, because inv_weigh = 2^32/weight)
A weight of a cfs_rq is the sum of weights of which entities
are queued on this cfs_rq, so it will overflow when there are
too many entities.
Although, overflow occurs very rarely, but it break fairness when
it occurs. 64-bits systems have more memory than 32-bit systems
and 64-bit systems can create more process usually, so overflow may
occur more frequently.
This patch guarantees fairness when overflow happens on 64-bit systems.
Thanks to the optimization of compiler, it changes nothing on 32-bit.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
I found a bug which can be reproduced by this way:(linux-2.6.26-rc5, x86-64)
(use 2^32, 2^33, ...., 2^63 as shares value)
# mkdir /dev/cpuctl
# mount -t cgroup -o cpu cpuctl /dev/cpuctl
# cd /dev/cpuctl
# mkdir sub
# echo 0x8000000000000000 > sub/cpu.shares
# echo $$ > sub/tasks
oops here! divide by zero.
This is because do_div() expects the 2th parameter to be 32 bits,
but unsigned long is 64 bits in x86_64.
Peter Zijstra pointed it out that the sane thing to do is limit the
shares value to something smaller instead of using an even more
expensive divide.
Also, I found another bug about "the shares value is too large":
pid1 and pid2 are set affinity to cpu#0
pid1 is attached to cg1 and pid2 is attached to cg2
if cg1/cpu.shares = 1024 cg2/cpu.shares = 2000000000
then pid2 got 100% usage of cpu, and pid1 0%
if cg1/cpu.shares = 1024 cg2/cpu.shares = 20000000000
then pid2 got 0% usage of cpu, and pid1 100%
And a weight of a cfs_rq is the sum of weights of which entities
are queued on this cfs_rq, so the shares value should be limited
to a smaller value.
I think that (1UL << 18) is a good limited value:
1) it's not too large, we can create a lot of group before overflow
2) it's several times the weight value for nice=-19 (not too small)
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
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>
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6:
USB: don't use reset-resume if drivers don't support it
USB: isp1760: Assign resource fields before adding hcd
isight_firmware: Avoid crash on loading invalid firmware
USB: fix build bug in USB_ISIGHTFW
This patch tries to identify which devices are able to accept
reset-resume handling, by checking that there is at least one
interface driver bound and that all of the drivers have a reset_resume
method defined. If these conditions don't hold then during resume
processing, the device is logicall disconnected.
This is only a temporary fix. Later on we will explicitly unbind
drivers that can't handle reset-resumes.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Cc: Oliver Neukum <oliver@neukum.org>
Cc: Pavel Machek <pavel@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This fixes the bogus "io mem 0x00000000" message printed
during driver init due to hcd->rsrc_start being assigned after
the call to usb_add_hcd().
Signed-off-by: Nate Case <ncase@xes-inc.com>
Acked-by: Sebastian Siewior <bigeasy@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Different tools generate slightly different formats of the isight
firmware. Ensure that the firmware buffer is not overrun, while still
ensuring that the correct amount of data is written if trailing data is
present.
Signed-off-by: Matthew Garrett <mjg@redhat.com>
Report-by: Justin Mattock <justinmattock@gmail.com>
Tested-by: Justin Mattock <justinmattock@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
USB: fix build bug in USB_ISIGHTFW
-tip tree testing found this build bug:
drivers/built-in.o: In function `isight_firmware_load':
isight_firmware.c:(.text+0x1ade08): undefined reference to `request_firmware'
isight_firmware.c:(.text+0x1adf9c): undefined reference to `release_firmware'
select FW_LOADER in USB_ISIGHTFW.
From: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Fix kernel-doc for new dev_set_name() function:
Warning(lin2626-rc5//drivers/base/core.c:767): No description found for parameter 'fmt'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
My laptop thinks that it's a good idea to give -73C as the critical
CPU temperature.... which isn't the best thing since it causes a shutdown
right at bootup.
Temperatures below freezing are clearly invalid critical thresholds
so just reject these as such.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Fixes problem introduced in 20080123, with fix for Unload operator.
Parse tree object can be already deleted; must use the opcode
within the WalkState.
ACPI: kmemcheck: Caught 16-bit read from freed memory
http://bugzilla.kernel.org/show_bug.cgi?id=10669
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Fixes a problem introduced in 20080514 where the status of
execution of _SST is incorrectly returned to the caller. _SST
is optional, and if it is AE_NOT_FOUND, the exception should be
ignored.
http://www.acpica.org/bugzilla/show_bug.cgi?id=716
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
This reverts a change introduced in version 20071019. The table
is now loaded at the namespace root even though this goes against
the ACPI specification. This provides compatibility with other
ACPI implementations.
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Only "SSDT" is acceptable to the ACPI spec, but tables are
seen with OEMx and null sigs. Therefore, signature validation
is worthless. Apparently MS ACPI accepts such signatures, ACPICA
must be compatible.
http://bugzilla.kernel.org/show_bug.cgi?id=10454
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Allows null field list in Field(), BankField(), and IndexField().
2.6.26-rc1 regression: ACPI fails to load SDT. - Dell M1530
http://bugzilla.kernel.org/show_bug.cgi?id=10606
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
If acpi_install_notify_handler() for a bay device fails, the bay driver is
superfluous. Most likely, another driver (like libata) is already caring
about this device anyway. Furthermore,
register_hotplug_dock_device(acpi_handle) from the dock driver must not be
called twice with the same handler. This would result in an endless loop
consuming 100% of CPU. So clean up and exit.
Signed-off-by: Holger Macht <hmacht@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Tim Pepper <lnxninja@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
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>
This is a SLIT sanity checking patch. It moves slit_valid() function to
generic ACPI code and does sanity checking for both x86 and ia64. It sets up
node_distance with LOCAL_DISTANCE and REMOTE_DISTANCE when hitting invalid
SLIT table on ia64. It also cleans up unused variable localities in
acpi_parse_slit() on x86.
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
When configuring the resources of an ACPI device, we first evaluate _CRS
to get a template of resource descriptors, then fill in the specific
resource values we want, and finally evaluate _SRS to actually configure
the device.
Some resources have optional fields, so the size of encoded descriptors
varies depending on the specific values. For example, IRQ descriptors can
be either two or three bytes long. The third byte contains triggering
information and can be omitted if the IRQ is edge-triggered and active
high.
The BIOS often assumes that IRQ descriptors in the _SRS buffer use the
same format as those in the _CRS buffer, so this patch enforces that
constraint.
The "Start Dependent Function" descriptor also has an optional byte, but
we don't currently encode those descriptors, so I didn't do anything for
those.
I have tested this patch on a Toshiba Portege 4000. Without the patch,
parport_pc claims the parallel port only if I use "pnpacpi=off". This
patch makes it work with PNPACPI.
This is an extension of a patch by Tom Jaeger:
http://bugzilla.kernel.org/show_bug.cgi?id=9487#c42
References:
http://bugzilla.kernel.org/show_bug.cgi?id=5832 Enabling ACPI Plug and Play in kernels >2.6.9 kills Parallel support
http://bugzilla.kernel.org/show_bug.cgi?id=9487 buggy firmware expects four-byte IRQ resource descriptor (was: Serial port disappears after Suspend on Toshiba R25)
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=1d5b285da1893b90507b081664ac27f1a8a3dc5b related ACPICA fix
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
When we encode IRQ resources, we should use the "shareable" flag we got
from _PRS rather than guessing based on the IRQ trigger mode.
This is based on a patch by Tom Jaeger:
http://bugzilla.kernel.org/show_bug.cgi?id=9487#c32
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Len Brown <len.brown@intel.com>
This patch updates the location of the ACPI homepage in MAINTAINERS.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Len Brown <len.brown@intel.com>
