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2009-05-29flat: fix data sections alignmentOskar Schirmer
The flat loader uses an architecture's flat_stack_align() to align the stack but assumes word-alignment is enough for the data sections. However, on the Xtensa S6000 we have registers up to 128bit width which can be used from userspace and therefor need userspace stack and data-section alignment of at least this size. This patch drops flat_stack_align() and uses the same alignment that is required for slab caches, ARCH_SLAB_MINALIGN, or wordsize if it's not defined by the architecture. It also fixes m32r which was obviously kaput, aligning an uninitialized stack entry instead of the stack pointer. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Oskar Schirmer <os@emlix.com> Cc: David Howells <dhowells@redhat.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Bryan Wu <cooloney@kernel.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Acked-by: Paul Mundt <lethal@linux-sh.org> Cc: Greg Ungerer <gerg@uclinux.org> Signed-off-by: Johannes Weiner <jw@emlix.com> Acked-by: Mike Frysinger <vapier.adi@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-29MAINTAINERS: change email address for Thomas DahlmannThomas Dahlmann
Signed-off-by: Thomas <dahlmann.thomas@arcor.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-29drivers/serial/mpc52xx_uart.c: fix array overindexing checkRoel Kluin
The check for an overindexing of mpc52xx_uart_{ports,nodes} has an off-by-one. Signed-off-by: Roel Kluin <roel.kluin@gmail.com> Acked-by: Wolfram Sang <w.sang@pengutronix.de> Acked-by: Grant Likely <grant.likely@secretlab.ca> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-29memcg: fix deadlock between lock_page_cgroup and mapping tree_lockDaisuke Nishimura
mapping->tree_lock can be acquired from interrupt context. Then, following dead lock can occur. Assume "A" as a page. CPU0: lock_page_cgroup(A) interrupted -> take mapping->tree_lock. CPU1: take mapping->tree_lock -> lock_page_cgroup(A) This patch tries to fix above deadlock by moving memcg's hook to out of mapping->tree_lock. charge/uncharge of pagecache/swapcache is protected by page lock, not tree_lock. After this patch, lock_page_cgroup() is not called under mapping->tree_lock. Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-29procfs: make errno values consistent when open pident vs exit(2) race occursKOSAKI Motohiro
proc_pident_instantiate() has following call flow. proc_pident_lookup() proc_pident_instantiate() proc_pid_make_inode() And, proc_pident_lookup() has following error handling. const struct pid_entry *p, *last; error = ERR_PTR(-ENOENT); if (!task) goto out_no_task; Then, proc_pident_instantiate should return ENOENT too when racing against exit(2) occur. EINAL has two bad reason. - it implies caller is wrong. bad the race isn't caller's mistake. - man 2 open don't explain EINVAL. user often don't handle it. Note: Other proc_pid_make_inode() caller already use ENOENT properly. Acked-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-29cred: #include init.h in cred.hAlexey Dobriyan
linux/cred.h can't be included as first header (alphabetical order) because it uses __init which is enough to break compilation on some archs. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: James Morris <jmorris@namei.org> Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-29oom: fix possible oom_dump_tasks NULL pointerDavid Rientjes
When /proc/sys/vm/oom_dump_tasks is enabled, it is possible to get a NULL pointer for tasks that have detached mm's since task_lock() is not held during the tasklist scan. Add the task_lock(). Acked-by: Nick Piggin <npiggin@suse.de> Acked-by: Mel Gorman <mel@csn.ul.ie> Cc: Rik van Riel <riel@redhat.com> Signed-off-by: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-29MAINTAINERS: pair EDAC-E752X P: and M: entriesJoe Perches
Entries should be P: name then M: email address. Signed-off-by: Joe Perches <joe@perches.com> Acked-by: Doug Thompson <dougthompson@xmission.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-27Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vapier/blackfin * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/vapier/blackfin: Blackfin: fix strncmp.o build error Blackfin: drop unneeded asm/.gitignore Blackfin: ignore generated vmlinux.lds MAINTAINERS: drop (subscribers-only) markings on Blackfin lists MAINTAINERS: update Blackfin items Blackfin: hook up preadv/pwritev syscalls
2009-05-27Merge branch 'merge' of ↵Linus Torvalds
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"
2009-05-27CacheFiles: Fixup renamed filenames in comments in internal.hDavid Howells
Fix up renamed filenames in comments in fs/cachefiles/internal.h. Originally, the files were all called cf-xxx.c, but they got renamed to just xxx.c. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-27FS-Cache: Fixup renamed filenames in comments in internal.hDavid Howells
Fix up renamed filenames in comments in fs/fscache/internal.h. Originally, the files were all called fsc-xxx.c, but they got renamed to just xxx.c. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-27Merge branch 'for-linus' of git://neil.brown.name/mdLinus Torvalds
* 'for-linus' of git://neil.brown.name/md: md: raid5: change incorrect usage of 'min' macro to 'min_t'
2009-05-27md: raid5: change incorrect usage of 'min' macro to 'min_t'NeilBrown
A recent patch to raid5.c use min on an int and a sector_t. This isn't allowed. So change it to min_t(sector_t,x,y). Signed-off-by: NeilBrown <neilb@suse.de>
2009-05-27powerpc: Fix up dma_alloc_coherent() on platforms without cache coherency.Benjamin Herrenschmidt
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>
2009-05-27powerpc: Minor cleanups of kernel virt address space definitionsBenjamin Herrenschmidt
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>
2009-05-27powerpc: Move dma-noncoherent.c from arch/powerpc/lib to arch/powerpc/mmBenjamin Herrenschmidt
(pre-requisite to make the next patches more palatable) Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2009-05-27Blackfin: fix strncmp.o build errorMike Frysinger
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>
2009-05-27Blackfin: drop unneeded asm/.gitignoreMike Frysinger
We don't create a include/asm/mach/ symlink anymore, so we don't need the .gitignore for it. Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-05-27Blackfin: ignore generated vmlinux.ldsMike Frysinger
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-05-27MAINTAINERS: drop (subscribers-only) markings on Blackfin listsMike Frysinger
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. Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-05-27MAINTAINERS: update Blackfin itemsMike Frysinger
With Bryan Wu having moved on to another job, push the slack onto some other ADI lackeys. Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-05-27Blackfin: hook up preadv/pwritev syscallsMike Frysinger
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2009-05-27Revert "powerpc: Rework dma-noncoherent to use generic vmalloc layer"Benjamin Herrenschmidt
This reverts commit 33f00dcedb0e22cdb156a23632814fc580fcfcf8. 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>
2009-05-26Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6: tomoyo: add missing call to cap_bprm_set_creds
2009-05-27tomoyo: add missing call to cap_bprm_set_credsHerton Ronaldo Krzesinski
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>
2009-05-26Merge branch 'x86-fixes-for-linus' of ↵Linus Torvalds
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
2009-05-26Merge branch 'for-linus' of ↵Linus Torvalds
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
2009-05-26Merge branch 'core-fixes-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: oprofile: fix cpu buffer size
2009-05-26x86: avoid back to back on_each_cpu in cpa_flush_arrayPallipadi, Venkatesh
Cleanup cpa_flush_array() to avoid back to back on_each_cpu() calls. [ Impact: optimizes fix 0af48f42df15b97080b450d24219dd95db7b929a ] Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2009-05-26Merge branch 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6Linus Torvalds
* '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
2009-05-26Merge branch 'for-linus' of ↵Linus Torvalds
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
2009-05-26Merge branch 'fixes' of ↵Linus Torvalds
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
2009-05-26lguest: fix on Intel when KVM loaded (unhandled trap 13)Rusty Russell
When KVM is loaded, and hence VT set up, the vmcall instruction in an lguest guest causes a #GP, not #UD. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-26kmod: Release sub_info on cred allocation failure.Tetsuo Handa
call_usermodehelper_setup() forgot to kfree(sub_info) when prepare_usermodehelper_creds() failed. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-05-26Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6Linus Torvalds
* 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 ...
2009-05-26Merge branch 'merge' of ↵Linus Torvalds
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/mm: Fix broken MMU PID stealing on !SMP
2009-05-26Merge branch 'for-linus' of git://neil.brown.name/mdLinus Torvalds
* 'for-linus' of git://neil.brown.name/md: md: don't use locked_ioctl. md: don't update curr_resync_completed without also updating reshape_position. md: raid5: avoid sector values going negative when testing reshape progress. md: export 'frozen' resync state through sysfs md: bitmap: improve bitmap maintenance code. md: improve errno return when setting array_size md: always update level / chunk_size / layout when writing v1.x metadata.
2009-05-26NFSv4: Fix the case where NFSv4 renewal failsTrond Myklebust
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... Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-05-26nfs: fix build error in nfsroot with initconstSam Ravnborg
fix build error with latest kbuild adjustments to initconst. The commit a447c0932445f92ce6f4c1bd020f62c5097a7842 ("vfs: Use const for kernel parser table") changed: static match_table_t __initdata tokens = { to static match_table_t __initconst tokens = { 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>
2009-05-26XPRTRDMA: fix client rpcrdma FRMR registration on mlx4 devicesVu Pham
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>
2009-05-26drm/i915: Add support for VGA load detection (pre-945).Ma Ling
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>
2009-05-26[CPUFREQ] powernow-k8: determine exact CPU frequency for HW PstatesAndreas Herrmann
Slightly modified by trenn@suse.de -> only do this on fam 10h and fam 11h. Currently powernow-k8 determines CPU frequency from ACPI PSS objects, but according to AMD family 11h BKDG this frequency is just a rounded value: "CoreFreq (MHz) = The CPU COF specified by MSRC001_00[6B:64][CpuFid] rounded to the nearest 100 Mhz." As a consequnce powernow-k8 reports wrong CPU frequency on some systems, e.g. on Turion X2 Ultra: powernow-k8: Found 1 AMD Turion(tm)X2 Ultra DualCore Mobile ZM-82 processors (2 cpu cores) (version 2.20.00) powernow-k8: 0 : pstate 0 (2200 MHz) powernow-k8: 1 : pstate 1 (1100 MHz) powernow-k8: 2 : pstate 2 (600 MHz) But this is wrong as frequency for Pstate2 is 550 MHz. x86info reports it correctly: #x86info -a |grep Pstate ... Pstate-0: fid=e, did=0, vid=24 (2200MHz) Pstate-1: fid=e, did=1, vid=30 (1100MHz) Pstate-2: fid=e, did=2, vid=3c (550MHz) (current) 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>
2009-05-26[CPUFREQ] powernow-k8 cleanup msg if BIOS does not export ACPI _PSS cpufreq dataThomas Renninger
- Make the message shorter and easier to grep for - Use printk_once instead of WARN_ONCE (functionality of these was mixed) Signed-off-by: Thomas Renninger <trenn@suse.de> Cc: Langsdorf, Mark <mark.langsdorf@amd.com> Signed-off-by: Dave Jones <davej@redhat.com>
2009-05-26[CPUFREQ] fix timer teardown in ondemand governorMathieu Desnoyers
* 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>
2009-05-26[CPUFREQ] fix timer teardown in conservative governorMathieu Desnoyers
* 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>
2009-05-26[CPUFREQ] remove rwsem lock from CPUFREQ_GOV_STOP callMathieu Desnoyers
* 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>
2009-05-26[CPUFREQ] powernow-k7 build fix when ACPI=nDave Jones
arch/x86/kernel/cpu/cpufreq/powernow-k7.c:172: warning: 'invalidate_entry' defined but not used Reported-by: Toralf Förster <toralf.foerster@gmx.de> Signed-off-by: Dave Jones <davej@redhat.com>
2009-05-26[CPUFREQ] add atom family to p4-clockmodJarod Wilson
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>
2009-05-25Merge branch 'linux-2.6.30.y' of ↵David S. Miller
git://git.kernel.org/pub/scm/linux/kernel/git/inaky/wimax