Hidetoshi Seto [Thu, 28 May 2009 02:41:01 +0000 (11:41 +0900)]
x86, mce: trivial clean up for mce-inject.c
Fix for:
WARNING: Use #include <linux/uaccess.h> instead of <asm/uaccess.h>
+#include <asm/uaccess.h>
WARNING: usage of NR_CPUS is often wrong - consider using cpu_possible(), num_possible_cpus(), for_each_possible_cpu(), etc
+ if (m.cpu >= NR_CPUS || !cpu_online(m.cpu))
ERROR: trailing whitespace
+/* $
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Cc: Andi Kleen <andi@firstfloor.org> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
H. Peter Anvin [Tue, 26 May 2009 05:18:17 +0000 (22:18 -0700)]
x86, mce: fix comment style in mce-inject.c
Fix style of winged comment in mce-inject.c.
[ Impact: comment only ]
Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
H. Peter Anvin [Tue, 26 May 2009 05:16:14 +0000 (22:16 -0700)]
x86, mce: add comment about mce_chrdev_ops being writable
Add a comment explaining that mce_chrdev_ops is intentionally
writable.
[ Impact: comment only ]
Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Allow user programs to write mce records into /dev/mcelog. When they do
that a fake machine check is triggered to test the machine check code.
This uses the MCE MSR wrappers added earlier.
The implementation is straight forward. There is a struct mce record
per CPU and the MCE MSR accesses get data from there if there is valid
data injected there. This allows to test the machine check code
relatively realistically because only the lowest layer of hardware
access is intercepted.
The test suite and injector are available at
git://git.kernel.org/pub/scm/utils/cpu/mce/mce-test.git
git://git.kernel.org/pub/scm/utils/cpu/mce/mce-inject.git
Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
x86, mce: add MSR read wrappers for easier error injection
This will be used by future patches to allow machine check error injection.
Right now it's a nop, except for adding some wrappers around the MSR reads.
This is early in the sequence to avoid too many conflicts.
Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Andi Kleen [Tue, 19 May 2009 20:49:07 +0000 (22:49 +0200)]
Export add_timer_on for modules
Needed in followon patch.
Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
x86, mce: document new 32bit mcelog requirement in Documentation/Changes
Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
That's very easy using the infrastructure enabled earlier for MCE_INTEL
Untested.
Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Enable the 64bit MCE_INTEL code (CMCI, thermal interrupts) for 32bit NEW_MCE.
Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
The 64bit machine check code is in many ways much better than
the 32bit machine check code: it is more specification compliant,
is cleaner, only has a single code base versus one per CPU,
has better infrastructure for recovery, has a cleaner way to communicate
with user space etc. etc.
Use the 64bit code for 32bit too.
This is the second attempt to do this. There was one a couple of years
ago to unify this code for 32bit and 64bit. Back then this ran into some
trouble with K7s and was reverted.
I believe this time the K7 problems (and some others) are addressed.
I went over the old handlers and was very careful to retain
all quirks.
But of course this needs a lot of testing on old systems. On newer
64bit capable systems I don't expect much problems because they have been
already tested with the 64bit kernel.
I made this a CONFIG for now that still allows to select the old
machine check code. This is mostly to make testing easier,
if someone runs into a problem we can ask them to try
with the CONFIG switched.
The new code is default y for more coverage.
Once there is confidence the 64bit code works well on older hardware
too the CONFIG_X86_OLD_MCE and the associated code can be easily
removed.
This causes a behaviour change for 32bit installations. They now
have to install the mcelog package to be able to log
corrected machine checks.
The 64bit machine check code only handles CPUs which support the
standard Intel machine check architecture described in the IA32 SDM.
The 32bit code has special support for some older CPUs which
have non standard machine check architectures, in particular
WinChip C3 and Intel P5. I made those a separate CONFIG option
and kept them for now. The WinChip variant could be probably
removed without too much pain, it doesn't really do anything
interesting. P5 is also disabled by default (like it
was before) because many motherboards have it miswired, but
according to Alan Cox a few embedded setups use that one.
Forward ported/heavily changed version of old patch, original patch
included review/fixes from Thomas Gleixner, Bert Wesarg.
Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
x86, mce: remove oops_begin() use in 64bit machine check
First 32bit doesn't have oops_begin, so it's a barrier of using
this code on 32bit.
On closer examination it turns out oops_begin is not
a good idea in a machine check panic anyways. All oops_begin
does it so check for recursive/parallel oopses and implement the
"wait on oops" heuristic. But there's actually no good reason
to lock machine checks against oopses or prevent them
from recursion. Also "wait on oops" does not really make
sense for a machine check too.
Replace it with a manual bust_spinlocks/console_verbose.
Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
x86, mce: remove machine check handler idle notify on 64bit
i386 has no idle notifiers, but the 64bit machine check
code uses them to wake up mcelog from a fatal machine check
exception.
For corrected machine checks found by the poller or
threshold interrupts going through an idle notifier is not needed
because the wake_up can is just done directly and doesn't
need the idle notifier. It is only needed for logging
exceptions.
To be honest I never liked the idle notifier even though I signed
off on it. On closer investigation the code actually turned out
to be nearly. Right now machine check exceptions on x86 are always
unrecoverable (lead to panic due to PCC), which means we never execute
the idle notifier path.
The only exception is the somewhat weird tolerant==3 case, which
ignores PCC. I'll fix this in a future patch in a much cleaner way.
So remove the "mcelog wakeup through idle notifier" code
from 64bit.
This allows to compile the 64bit machine check handler on 32bit
which doesn't have idle notifiers.
Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
x86, mce: move mce_disabled option into common 32bit/64bit code
It's the same function, so let's share it.
Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
x86, mce: rename 64bit mce_dont_init to mce_disabled
Give it the same name as on 32bit. This makes further merging easier.
Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
x86, mce: use a call vector to call the 64bit mce handler
Allows to call different machine check handlers from the low
level machine check entry vector.
This is needed for later when it will be used for 32bit too.
Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Various K7 have broken bank 0s. Don't enable it by default
Port from the 32bit code.
Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
x86, mce: implement the PPro bank 0 quirk in the 64bit machine check code
Quoting the comment:
* SDM documents that on family 6 bank 0 should not be written
* because it aliases to another special BIOS controlled
* register.
* But it's not aliased anymore on model 0x1a+
* Don't ignore bank 0 completely because there could be a valid
* event later, merely don't write CTL0.
This is mostly a port on the 32bit code, except that 32bit
always didn't write it and didn't have the 0x1a heuristic. I checked
with the CPU designers that the quirk is not required starting with
this model.
Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
x86, mce: initial steps to make 64bit mce code 32bit clean
Replace unsigned long with u64s if they need to contain 64bit values.
Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
This file has been modified many times along the years, by multiple
authors, so the general style and structure has diverged in a number
of areas making this file hard to read.
So fix the coding style match that of the rest of the x86 arch code.
[ Impact: cleanup ]
Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Linus Torvalds [Wed, 27 May 2009 17:58:23 +0000 (10:58 -0700)]
Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
powerpc: Fix up dma_alloc_coherent() on platforms without cache coherency.
powerpc: Minor cleanups of kernel virt address space definitions
powerpc: Move dma-noncoherent.c from arch/powerpc/lib to arch/powerpc/mm
Revert "powerpc: Rework dma-noncoherent to use generic vmalloc layer"
powerpc: Fix up dma_alloc_coherent() on platforms without cache coherency.
The implementation we just revived has issues, such as using a
Kconfig-defined virtual address area in kernel space that nothing
actually carves out (and thus will overlap whatever is there),
or having some dependencies on being self contained in a single
PTE page which adds unnecessary constraints on the kernel virtual
address space.
This fixes it by using more classic PTE accessors and automatically
locating the area for consistent memory, carving an appropriate hole
in the kernel virtual address space, leaving only the size of that
area as a Kconfig option. It also brings some dma-mask related fixes
from the ARM implementation which was almost identical initially but
grew its own fixes.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
powerpc: Minor cleanups of kernel virt address space definitions
Make FIXADDR_TOP a compile time constant and cleanup a
couple of definitions relative to the layout of the kernel
address space on ppc32. We also print out that layout at
boot time for debugging purposes.
This is a pre-requisite for properly fixing non-coherent
DMA allocactions.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Mike Frysinger [Tue, 26 May 2009 09:03:52 +0000 (05:03 -0400)]
Blackfin: fix strncmp.o build error
Fix some more fallout of the string changes:
CC arch/blackfin/lib/strncmp.o
In file included from include/linux/bitmap.h:9,
from include/linux/nodemask.h:90,
from include/linux/mmzone.h:17,
from include/linux/gfp.h:5,
from include/linux/kmod.h:23,
from include/linux/module.h:14,
from arch/blackfin/lib/strncmp.c:14:
include/linux/string.h: In function ‘strstarts’:
include/linux/string.h:132: error: implicit declaration of function ‘strncmp’
make[1]: *** [arch/blackfin/lib/strncmp.o] Error 1
Signed-off-by: Mike Frysinger <vapier@gentoo.org> CC: Rusty Russell <rusty@rustcorp.com.au>
Mike Frysinger [Mon, 18 May 2009 08:33:07 +0000 (04:33 -0400)]
MAINTAINERS: drop (subscribers-only) markings on Blackfin lists
All of the Blackfin lists are transparently moderated for non-subscribers.
i.e. there are no annoying notices and people get whitelisted after first
their posting.
While it was a good idea to try to use the mm/vmalloc.c allocator instead
of our own (in fact, ours is itself a dup on an old variant of the vmalloc
one), unfortunately, the approach is terminally busted since
dma_alloc_coherent() can be called at interrupt time or in atomic contexts
and there's little chances we'll make the code in mm/vmalloc.c cope with\ that :-(
Until we can get the generic code to forbid that idiocy and fix all
drivers abusing it, we pretty much have no choice but revert to
our custom virtual space allocator.
There's also a problem with SMP safety since freeing such mapping
would require an IPI which cannot be done at interrupt time.
However, right now, I don't think we support any platform that is
both SMP and has non-coherent DMA (don't laugh, I know such things
do exist !) so we can sort that out later.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
cap_bprm_set_creds() has to be called from security_bprm_set_creds().
TOMOYO forgot to call cap_bprm_set_creds() from tomoyo_bprm_set_creds()
and suid executables were not being working.
Make sure we call cap_bprm_set_creds() with TOMOYO, to set credentials
properly inside tomoyo_bprm_set_creds().
Signed-off-by: Herton Ronaldo Krzesinski <herton@mandriva.com.br> Acked-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
Linus Torvalds [Tue, 26 May 2009 22:06:12 +0000 (15:06 -0700)]
Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86: avoid back to back on_each_cpu in cpa_flush_array
x86, relocs: ignore R_386_NONE in kernel relocation entries
Linus Torvalds [Tue, 26 May 2009 21:48:36 +0000 (14:48 -0700)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/anholt/drm-intel
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/anholt/drm-intel:
drm/i915: Add support for VGA load detection (pre-945).
drm/i915: Use an I2C algo to do the flip to SDVO DDC bus.
drm/i915: Determine type before initialising connector
drm/i915: Return SDVO LVDS VBT mode if no EDID modes are detected.
drm/i915: Fetch SDVO LVDS mode lines from VBT, then reserve them
i915: support 8xx desktop cursors
drm/i915: allocate large pointer arrays with vmalloc
Linus Torvalds [Tue, 26 May 2009 19:15:35 +0000 (12:15 -0700)]
Merge branch 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6
* 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6:
NFSv4: Fix the case where NFSv4 renewal fails
nfs: fix build error in nfsroot with initconst
XPRTRDMA: fix client rpcrdma FRMR registration on mlx4 devices
Linus Torvalds [Tue, 26 May 2009 19:14:46 +0000 (12:14 -0700)]
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6:
ALSA: hda - Add missing check of pin vref 50 and others in Realtek codecs
ALSA: hda - Add 5stack-no-fp model for STAC927x
ALSA: hda - Add forced codec-slots for ASUS W5Fm
Linus Torvalds [Tue, 26 May 2009 19:13:33 +0000 (12:13 -0700)]
Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/davej/cpufreq:
[CPUFREQ] powernow-k8: determine exact CPU frequency for HW Pstates
[CPUFREQ] powernow-k8 cleanup msg if BIOS does not export ACPI _PSS cpufreq data
[CPUFREQ] fix timer teardown in ondemand governor
[CPUFREQ] fix timer teardown in conservative governor
[CPUFREQ] remove rwsem lock from CPUFREQ_GOV_STOP call
[CPUFREQ] powernow-k7 build fix when ACPI=n
[CPUFREQ] add atom family to p4-clockmod
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (21 commits)
r8169: avoid losing MSI interrupts
tcp: tcp_vegas ssthresh bugfix
mac8390: fix regression caused during net_device_ops conversion
gianfar: fix BUG under load after introduction of skb recycling
wimax/i2400m: usb: fix device reset on autosuspend while not yet idle
RxRPC: Error handling for rxrpc_alloc_connection()
ipv4: Fix oops with FIB_TRIE
pktgen: do not access flows[] beyond its length
gigaset: beyond ARRAY_SIZE of iwb->data
IPv6: set RTPROT_KERNEL to initial route
net: fix rtable leak in net/ipv4/route.c
net: fix length computation in rt_check_expire()
wireless: beyond ARRAY_SIZE of intf->crypto_stats
iwlwifi: update 5000 ucode support to version 2 of API
cfg80211: fix race between core hint and driver's custom apply
airo: fix airo_get_encode{,ext} buffer overflow like I mean it...
ath5k: fix interpolation with equal power levels
iwlwifi: do not cancel delayed work inside spin_lock_irqsave
ath5k: fix exp off-by-one when computing OFDM delta slope
wext: verify buffer size for SIOCSIWENCODEEXT
...
Trond Myklebust [Tue, 26 May 2009 18:51:00 +0000 (14:51 -0400)]
NFSv4: Fix the case where NFSv4 renewal fails
If the asynchronous lease renewal fails (usually due to a soft timeout),
then we _must_ schedule state recovery in order to ensure that we don't
lose the lease unnecessarily or, if the lease is already lost, that we
recover the locking state promptly...
But the missing const causes popwerpc to fail with latest
updates to __initconst like this:
fs/nfs/nfsroot.c:400: error: __setup_str_nfs_root_setup causes a section type conflict
fs/nfs/nfsroot.c:400: error: __setup_str_nfs_root_setup causes a section type conflict
The bug is only present with kbuild-next.
Following patch has been build tested.
Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Acked-by: Jan Beulich <jbeulich@novell.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Vu Pham [Tue, 26 May 2009 18:51:00 +0000 (14:51 -0400)]
XPRTRDMA: fix client rpcrdma FRMR registration on mlx4 devices
mlx4/connectX FRMR requires local write enable together with remote
rdma write enable. This fixes NFS/RDMA operation over the ConnectX
Infiniband HCA in the default memreg mode.
Signed-off-by: Vu Pham <vu@mellanox.com> Signed-off-by: Tom Talpey <tmtalpey@gmail.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Ma Ling [Tue, 26 May 2009 03:31:00 +0000 (11:31 +0800)]
drm/i915: Add support for VGA load detection (pre-945).
Two approaches for VGA detections: hot plug detection for 945G onwards
and load pipe detection for Pre-945G. Load pipe detection will get one free
pipe, set border color as red and blue, then check CRT status by
swf register. This is a sync-up with the 2D driver.
Signed-off-by: Ma Ling <ling.ma@intel.com> Signed-off-by: Eric Anholt <eric@anholt.net>
Solution is to determine the frequency directly from Pstate MSRs instead
of using rounded values from ACPI table.
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com> Signed-off-by: Thomas Renninger <trenn@suse.de> Signed-off-by: Dave Jones <davej@redhat.com>
* Rafael J. Wysocki (rjw@sisk.pl) wrote:
> This message has been generated automatically as a part of a report
> of regressions introduced between 2.6.28 and 2.6.29.
>
> The following bug entry is on the current list of known regressions
> introduced between 2.6.28 and 2.6.29. Please verify if it still should
> be listed and let me know (either way).
>
>
> Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=13186
> Subject : cpufreq timer teardown problem
> Submitter : Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
> Date : 2009-04-23 14:00 (24 days old)
> References : http://marc.info/?l=linux-kernel&m=124049523515036&w=4
> Handled-By : Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
> Patch : http://patchwork.kernel.org/patch/19754/
> http://patchwork.kernel.org/patch/19753/
>
(updated changelog)
cpufreq fix timer teardown in ondemand governor
The problem is that dbs_timer_exit() uses cancel_delayed_work() when it should
use cancel_delayed_work_sync(). cancel_delayed_work() does not wait for the
workqueue handler to exit.
The ondemand governor does not seem to be affected because the
"if (!dbs_info->enable)" check at the beginning of the workqueue handler returns
immediately without rescheduling the work. The conservative governor in
2.6.30-rc has the same check as the ondemand governor, which makes things
usually run smoothly. However, if the governor is quickly stopped and then
started, this could lead to the following race :
dbs_enable could be reenabled and multiple do_dbs_timer handlers would run.
This is why a synchronized teardown is required.
The following patch applies to, at least, 2.6.28.x, 2.6.29.1, 2.6.30-rc2.
Depends on patch
cpufreq: remove rwsem lock from CPUFREQ_GOV_STOP call
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> CC: Andrew Morton <akpm@linux-foundation.org> CC: gregkh@suse.de CC: stable@kernel.org CC: cpufreq@vger.kernel.org CC: Ingo Molnar <mingo@elte.hu> CC: rjw@sisk.pl CC: Ben Slusky <sluskyb@paranoiacs.org> Signed-off-by: Dave Jones <davej@redhat.com>
[CPUFREQ] fix timer teardown in conservative governor
* Rafael J. Wysocki (rjw@sisk.pl) wrote:
> This message has been generated automatically as a part of a report
> of regressions introduced between 2.6.28 and 2.6.29.
>
> The following bug entry is on the current list of known regressions
> introduced between 2.6.28 and 2.6.29. Please verify if it still should
> be listed and let me know (either way).
>
>
> Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=13186
> Subject : cpufreq timer teardown problem
> Submitter : Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
> Date : 2009-04-23 14:00 (24 days old)
> References : http://marc.info/?l=linux-kernel&m=124049523515036&w=4
> Handled-By : Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
> Patch : http://patchwork.kernel.org/patch/19754/
> http://patchwork.kernel.org/patch/19753/
>
(re-send with updated changelog)
cpufreq fix timer teardown in conservative governor
The problem is that dbs_timer_exit() uses cancel_delayed_work() when it should
use cancel_delayed_work_sync(). cancel_delayed_work() does not wait for the
workqueue handler to exit.
The ondemand governor does not seem to be affected because the
"if (!dbs_info->enable)" check at the beginning of the workqueue handler returns
immediately without rescheduling the work. The conservative governor in
2.6.30-rc has the same check as the ondemand governor, which makes things
usually run smoothly. However, if the governor is quickly stopped and then
started, this could lead to the following race :
dbs_enable could be reenabled and multiple do_dbs_timer handlers would run.
This is why a synchronized teardown is required.
Depends on patch
cpufreq: remove rwsem lock from CPUFREQ_GOV_STOP call
The following patch applies to 2.6.30-rc2. Stable kernels have a similar
issue which should also be fixed, but the code changed between 2.6.29
and 2.6.30, so this patch only applies to 2.6.30-rc.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> CC: Andrew Morton <akpm@linux-foundation.org> CC: gregkh@suse.de CC: stable@kernel.org CC: cpufreq@vger.kernel.org CC: Ingo Molnar <mingo@elte.hu> CC: rjw@sisk.pl CC: Ben Slusky <sluskyb@paranoiacs.org> Signed-off-by: Dave Jones <davej@redhat.com>
[CPUFREQ] remove rwsem lock from CPUFREQ_GOV_STOP call
* Rafael J. Wysocki (rjw@sisk.pl) wrote:
> This message has been generated automatically as a part of a report
> of regressions introduced between 2.6.28 and 2.6.29.
>
> The following bug entry is on the current list of known regressions
> introduced between 2.6.28 and 2.6.29. Please verify if it still should
> be listed and let me know (either way).
>
>
> Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=13186
> Subject : cpufreq timer teardown problem
> Submitter : Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
> Date : 2009-04-23 14:00 (24 days old)
> References : http://marc.info/?l=linux-kernel&m=124049523515036&w=4
> Handled-By : Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
> Patch : http://patchwork.kernel.org/patch/19754/
> http://patchwork.kernel.org/patch/19753/
The patches linked above depend on the following patch to remove
circular locking dependency :
cpufreq: remove rwsem lock from CPUFREQ_GOV_STOP call
(the following issue was faced when using cancel_delayed_work_sync() in the
timer teardown (which fixes a race).
* KOSAKI Motohiro (kosaki.motohiro@jp.fujitsu.com) wrote:
> Hi
>
> my box output following warnings.
> it seems regression by commit 7ccc7608b836e58fbacf65ee4f8eefa288e86fac.
>
> A: work -> do_dbs_timer() -> cpu_policy_rwsem
> B: store() -> cpu_policy_rwsem -> cpufreq_governor_dbs() -> work
>
>
Hrm, I think it must be due to my attempt to fix the timer teardown race
in ondemand governor mixed with new locking behavior in 2.6.30-rc.
The rwlock seems to be taken around the whole call to
cpufreq_governor_dbs(), when it should be only taken around accesses to
the locked data, and especially *not* around the call to
dbs_timer_exit().
Reverting my fix attempt would put the teardown race back in place
(replacing the cancel_delayed_work_sync by cancel_delayed_work).
Instead, a proper fix would imply modifying this critical section :
cpufreq.c: __cpufreq_remove_dev()
...
if (cpufreq_driver->target)
__cpufreq_governor(data, CPUFREQ_GOV_STOP);
unlock_policy_rwsem_write(cpu);
To make sure the __cpufreq_governor() callback is not called with rwsem
held. This would allow execution of cancel_delayed_work_sync() without
being nested within the rwsem.
Applies on top of the 2.6.30-rc5 tree.
Required to remove circular dep in teardown of both conservative and
ondemande governors so they can use cancel_delayed_work_sync().
CPUFREQ_GOV_STOP does not modify the policy, therefore this locking seemed
unneeded.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca> CC: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Greg KH <greg@kroah.com> CC: Ingo Molnar <mingo@elte.hu> CC: "Rafael J. Wysocki" <rjw@sisk.pl> CC: Ben Slusky <sluskyb@paranoiacs.org> CC: Chris Wright <chrisw@sous-sol.org> CC: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dave Jones <davej@redhat.com>
Jarod Wilson [Fri, 6 Mar 2009 20:24:57 +0000 (20:24 +0000)]
[CPUFREQ] add atom family to p4-clockmod
Some atom procs don't do freq scaling (such as the atom 330 on my own
littlefalls2 board). By adding the atom family here, we at least get
the benefit of passive cooling in a thermal emergency. Not sure how
to see that its actually helping any, but the driver does bind and
claim its functioning on my atom 330.
Signed-off-by: Jarod Wilson <jarod@redhat.com> Signed-off-by: Dave Jones <davej@redhat.com>
David Dillow [Fri, 22 May 2009 15:29:34 +0000 (15:29 +0000)]
r8169: avoid losing MSI interrupts
The 8169 chip only generates MSI interrupts when all enabled event
sources are quiescent and one or more sources transition to active. If
not all of the active events are acknowledged, or a new event becomes
active while the existing ones are cleared in the handler, we will not
see a new interrupt.
The current interrupt handler masks off the Rx and Tx events once the
NAPI handler has been scheduled, which opens a race window in which we
can get another Rx or Tx event and never ACK'ing it, stopping all
activity until the link is reset (ifconfig down/up). Fix this by always
ACK'ing all event sources, and loop in the handler until we have all
sources quiescent.
Signed-off-by: David Dillow <dave@thedillows.org> Tested-by: Michael Buesch <mb@bu3sch.de> Signed-off-by: David S. Miller <davem@davemloft.net>
Tejun Heo [Tue, 26 May 2009 05:42:40 +0000 (14:42 +0900)]
x86, relocs: ignore R_386_NONE in kernel relocation entries
For relocatable 32bit kernels, boot/compressed/relocs.c processes
relocation entries in the kernel image and appends it to the kernel
image such that boot/compressed/head_32.S can relocate the kernel.
The kernel image is one statically linked object and only uses two
relocation types - R_386_PC32 and R_386_32, of the two only the latter
needs massaging during kernel relocation and thus handled by relocs.
R_386_PC32 is ignored and all other relocation types are considered
error.
When the target of a relocation resides in a discarded section,
binutils doesn't throw away the relocation record but nullifies it by
changing it to R_386_NONE, which unfortunately makes relocs fail.
The problem was triggered by yet out-of-tree x86 stack unwind patches
but given the binutils behavior, ignoring R_386_NONE is the right
thing to do.
The problem has been tracked down to binutils behavior by Jan Beulich.
[ Impact: fix build with certain binutils by ignoring R_386_NONE ]
Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Jan Beulich <JBeulich@novell.com> Cc: Ingo Molnar <mingo@elte.hu>
LKML-Reference: <4A1B8150.40702@kernel.org> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
projects / linux-beck.git / log