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2009-08-15sh: Set the cfa_offset to 0 if we see a DW_CFA_def_cfa_register opMatt Fleming
The way that the CFA is calculated can change as we progress through a function. If we see a DW_CFA_def_cfa_register op we need to reset the frame's cfa_offset value which may have been previously setup. Signed-off-by: Matt Fleming <matt@console-pimps.org> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-15sh: delay slot future proofing via EXPMASK on SH-4A parts.Paul Mundt
This implements EXPMASK initialization code for SH-4A parts, where it is possible to disable compat features that will go away in newer cores. Presently this includes disabling support for non-nop instructions in the rte delay slot, as well as a sleep instruction being placed in a delay slot (neither of which the kernel does any longer). As a result of this, any future offenders will have illegal slot exceptions generated for them. Associative writes for the memory-mapped cache array are still left enabled, until such a point that special cache operations for SH-4A are provided to move off of the current (and rather dated) SH-4 versions. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-15sh: Make sure rte delay slots are nopped out on all parts.Paul Mundt
Future SH parts do not support any instruction but a nop in the rte delay slot, so make the change for all offending parts. SH-5 is excluded from this, and already has its own set of restrictions with regards to rte delay slot handling. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-15sh: stacktrace: Properly terminate the trace entry buffer.Paul Mundt
This inserts a ULONG_MAX entry at the end of the valid entries in the stack trace buffer so the default code doesn't need to scan to the end of available slots. This also makes the trace buffer termination behaviour consistent with the other architectures. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-15sh: flag the default unwinder as reliable.Paul Mundt
This flags the default unwinder as reliable, as it tends to be reliable enough for the purposes of the stacktrace buffer. We leave the unreliable cases for the unwind methods that we know to be completely broken. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-15sh: stacktrace: Add reliability checks in address saving ops.Paul Mundt
This adopts the reliability checks from the x86 stacktrace code so known bad addresses are not recorded in the stack trace buffer. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-14sh: unwinder: Convert frame allocations to GFP_ATOMIC.Paul Mundt
save_stack_trace_tsk() and friends can be called from atomic context (as triggered by latencytop), and subsequently hit two problematic allocation points that were using GFP_KERNEL (these were dwarf_unwind_stack() and dwarf_frame_alloc_regs()). Convert these over to GFP_ATOMIC and get latencytop working with the DWARF unwinder. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-14Merge branch 'sh/dwarf-unwinder'Paul Mundt
2009-08-14sh: Delete DWARF_ARCH_UNWIND_OFFSETMatt Fleming
Trying to figure out the best value for DWARF_ARCH_UNWIND_OFFSET is tricky at best. Various things can change the size (and offset from the beginning of the function) of the prologue. Notably, turning on ftrace adds calls to mcount at the beginning of functions, thereby pushing the prologue further into the function. So replace DWARF_ARCH_UNWIND_OFFSET with some code that continues to execute CFA instructions until the value of return address register is defined. This is safe to do because we know that the return address must have been pushed onto the frame before our first function call; we just can't figure out where at compile-time. Signed-off-by: Matt Fleming <matt@console-pimps.org> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-14sh: oprofile: Kill off dead valid_kernel_stack().Paul Mundt
This is no longer used, kill it off. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-14sh: unwinder: Restore put_unaligned() for an unaligned destination.Paul Mundt
The destination address might be unaligned, so set it with put_unaligned() for safety. This restores the previous behaviour, albeit through the proper API. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-14sh: unwinder: Fix up usage of unaligned accessors.Paul Mundt
This was using internal symbols for unaligned accesses, bypassing the exposed interface for variable sized safe accesses. This converts all of the __get_unaligned_cpuXX() users over to get_unaligned() directly, relying on the cast to select the proper internal routine. Additionally, the __put_unaligned_cpuXX() case is superfluous given that the destination address is aligned in all of the current cases, so just drop that outright. Furthermore, this switches to the asm/unaligned.h header instead of the asm-generic version, which was silently bypassing the SH-4A optimized unaligned ops. Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-14sh: Add CFI annotations for exception return.Matt Fleming
Annotate various assembly code paths with CFI assembler directives so that DWARF unwind info is available for the unwinder. Signed-off-by: Matt Fleming <matt@console-pimps.org> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-14sh: Setup the frame register in asm codeMatt Fleming
In order to use DWARF unwinder info the frame register has to contain a valid value. Whilst GCC takes care of this for C code, we have to do it ourselves for assembly. Signed-off-by: Matt Fleming <matt@console-pimps.org> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-14sh: dwarf unwinder support.Matt Fleming
This is a first cut at a generic DWARF unwinder for the kernel. It's still lacking DWARF64 support and the DWARF expression support hasn't been tested very well but it is generating proper stacktraces on SH for WARN_ON() and NULL dereferences. Signed-off-by: Matt Fleming <matt@console-pimps.org> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-13sh: Use the new stack unwinder APIMatt Fleming
Instead of implementing our own stack unwinder via dump_trace() we should use the new stack unwinder API because it is more modular. This change allows us to decouple the interface for generating stacktraces from the implementation of a stack unwinder. Signed-off-by: Matt Fleming <matt@console-pimps.org> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-13sh: Allow multiple stack unwinders to be setupMatt Fleming
Provide an interface for registering stack unwinders, where each unwinder is given a rating that describes its accuracy and complexity. The more accurate an unwinder is, the more complex it is. If a the current stack unwinder faults, then the stack unwinder with the next highest accuracy will be used in its place (provided one is available). For example, this allows unwinders, such as the DWARF unwinder, to liberally sprinkle BUG()s to catch badly formed DWARF debug info. Signed-off-by: Matt Fleming <matt@console-pimps.org> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-13sh: Use the generalized stacktrace opsMatt Fleming
Copy the stacktrace ops code from x86 and provide a central function for use by functions that need to dump a callstack. Signed-off-by: Matt Fleming <matt@console-pimps.org> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-13sh: use printk_onceMarcin Slusarz
Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com> Cc: linux-sh@vger.kernel.org Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-13Merge branch 'sh/stable-updates'Paul Mundt
2009-08-13sh: fix i2c init order on ap325rxa V2Magnus Damm
Convert the AP325RXA board code to register devices at arch_initcall() time instead of device_initcall(). This fix unbreaks pcf8563 RTC driver support. Signed-off-by: Magnus Damm <damm@igel.co.jp> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-13sh: fix i2c init order on Migo-R V2Magnus Damm
Convert the Migo-R board code to register devices at arch_initcall() time instead of __initcall(). This fix unbreaks migor_ts touch screen driver support. Signed-off-by: Magnus Damm <damm@igel.co.jp> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-13sh: convert processor device setup functions to arch_initcall()Magnus Damm
Convert the processor platform device setup functions from __initcall() and sometimes device_initcall() to arch_initcall(). This makes sure that the platform devices are registered a bit earlier so the devices are available when drivers register using initcall levels earlier than device_initcall(). A good example is platform devices needed by i2c-sh_mobile.c which registers a bit earlier using subsys_initcall(). Signed-off-by: Magnus Damm <damm@igel.co.jp> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-12Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-blockLinus Torvalds
* 'for-linus' of git://git.kernel.dk/linux-2.6-block: Remove double removal of blktrace directory
2009-08-12Remove double removal of blktrace directoryAlan D. Brunelle
commit fd51d251e4cdb21f68e9dbc4336514d64a105a79 Author: Stefan Raspl <raspl@linux.vnet.ibm.com> Date: Tue May 19 09:59:08 2009 +0200 blktrace: remove debugfs entries on bad path added in an explicit invocation of debugfs_remove for bt->dir, in blk_remove_buf_file_callback we are also getting the directory removed. On occasion I am seeing memory corruption that I have bisected down to this commit. [The testing involves a (long) series of I/O benchmarks with blktrace invoked around the actual runs.] I believe that this committed patch is correct, but the problem actually lies in the code in blk_remove_buf_file_callback. With this patch I am able to consistently get complete runs whereas previously I could not get a single run to complete. The first part of the patch simply moves the debugfs_remove below the relay_close: the relay_close call will remove files under bt->dir, and so we should not remove the directory until all the files we created have been removed. (Note: This is not sufficient to fix the problem - the file system code has ref counts on the directoy, so our invocation does not cause the directory to actually be removed. Nonetheless, we should not rely upon that feature.) Signed-off-by: Alan D. Brunelle <alan.brunelle@hp.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-08-12Merge branch 'for-linus' of git://oss.sgi.com/xfs/xfsLinus Torvalds
* 'for-linus' of git://oss.sgi.com/xfs/xfs: xfs: fix spin_is_locked assert on uni-processor builds xfs: check for dinode realtime flag corruption use XFS_CORRUPTION_ERROR in xfs_btree_check_sblock xfs: switch to NOFS allocation under i_lock in xfs_attr_rmtval_get xfs: switch to NOFS allocation under i_lock in xfs_readlink_bmap xfs: switch to NOFS allocation under i_lock in xfs_attr_rmtval_set xfs: switch to NOFS allocation under i_lock in xfs_buf_associate_memory xfs: switch to NOFS allocation under i_lock in xfs_dir_cilookup_result xfs: switch to NOFS allocation under i_lock in xfs_da_buf_make xfs: switch to NOFS allocation under i_lock in xfs_da_state_alloc xfs: switch to NOFS allocation under i_lock in xfs_getbmap xfs: avoid memory allocation under m_peraglock in growfs code
2009-08-12Merge 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 - Don't override ADC definitions for ALC codecs ALSA: hda - Add missing vmaster initialization for ALC269 ASoC: Add missing DRV_NAME definitions for fsl/* drivers
2009-08-12Merge branch 'zerolen' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/misc-2.6 * 'zerolen' of git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/misc-2.6: Remove zero-length file drivers/mtd/maps/sbc8240.c
2009-08-12Merge branch 'upstream-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev * 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev: ahci: add workaround for on-board 5723s on some gigabyte boards ahci: Soften up the dmesg on SB600 PMP softreset failure recovery Documentation/kernel-parameters.txt: document libata's ignore_hpa option sata_nv: MSI support, disabled by default libata: OCZ Vertex can't do HPA pata_atiixp: fix second channel support pata_at91: fix resource release
2009-08-12NFS: Fix an O_DIRECT Oops...Trond Myklebust
We can't call nfs_readdata_release()/nfs_writedata_release() without first initialising and referencing args.context. Doing so inside nfs_direct_read_schedule_segment()/nfs_direct_write_schedule_segment() causes an Oops. We should rather be calling nfs_readdata_free()/nfs_writedata_free() in those cases. Looking at the O_DIRECT code, the "struct nfs_direct_req" is already referencing the nfs_open_context for us. Since the readdata and writedata structures carry a reference to that, we can simplify things by getting rid of the extra nfs_open_context references, so that we can replace all instances of nfs_readdata_release()/nfs_writedata_release(). Reported-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Tested-by: Catalin Marinas <catalin.marinas@arm.com> Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-08-12Remove zero-length file drivers/mtd/maps/sbc8240.cJeff Garzik
It was "deleted" in commit 2bf961b7ccd69e108ac435c67e2b0522b403c578 Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-08-12ahci: add workaround for on-board 5723s on some gigabyte boardsTejun Heo
Some gigabytes have on-board SIMG5723s connected to JMB ahcis. These are used to implement hardware raid. Unfortunately some firmware revisions on these 5723s don't bring the link down when all the downstream ports are unoccupied while not responding to reset protocol which makes libata think that there's device attached to the port but is not responding and retry. This results in painfully wrong boot detection time for these ports when they're empty. This patch quirks those boards such that ahci gives up after the initial timeout. Combined with parallel probing, this gives quick enough probing and also is safe because SIMG5723 will respond to the first try if any of the downstream ports is occupied. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Marc Bowes <marcbowes@gmail.com> Reported-by: Nicolas Mailhot <Nicolas.Mailhot@LaPoste.net> Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-08-12ahci: Soften up the dmesg on SB600 PMP softreset failure recoveryShane Huang
Too strong words led to spurious bug reports: Novell bugzilla #527748, RedHat bugzilla #468800. This patch is used to soften up the dmesg on SB600 PMP softreset failure recovery, so as to remove the scariness and concern from community. Reported-by: pgnet Dev <pgnet.dev@gmail.com> Signed-off-by: Shane Huang <shane.huang@amd.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-08-12Documentation/kernel-parameters.txt: document libata's ignore_hpa optionMichael Prokop
By default the kernel honors the HPA (host protected area) of hard drives. Using libata's ignore_hpa module option it's possible to change this behaviour. Document usage and options of libata.ignore_hpa in Documentation/kernel-parameters.txt. Signed-off-by: Michael Prokop <mika@grml.org> Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-08-12sata_nv: MSI support, disabled by defaultTony Vroon
At least the nVidia MCP55 controller quite happily supports MSI. This adds an option to use it. It is disabled by default. As per feedback by Robert Hancock, it will honour the user request as the kernel will not enable MSI where the controller or the specific system configuration do not support it. Signed-off-by: Tony Vroon <tony@linx.net> Cc: Robert Hancock <hancockrwd@gmail.com> Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-08-12libata: OCZ Vertex can't do HPATejun Heo
OCZ Vertex SSD can't do HPA and not in a usual way. It reports HPA, allows unlocking but then fails all IOs which fall in the unlocked area. Quirk it so that HPA unlocking is not used for the device. Reported by Daniel Perup in bnc#522414. https://bugzilla.novell.com/show_bug.cgi?id=522414 Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Daniel Perup <probe@spray.se> Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-08-12pata_atiixp: fix second channel supportBartlomiej Zolnierkiewicz
PIO and MWDMA timings are never programmed for the second channel because timing registers are treated as 16-bit long ones. The bug is an attixp -> pata_atiixp regression and goes back to: commit 669a5db411d85a14f86cd92bc16bf7ab5b8aa235 Author: Jeff Garzik <jeff@garzik.org> Date: Tue Aug 29 18:12:40 2006 -0400 [libata] Add a bunch of PATA drivers. Cc: Krystian Juskowiak <jusko@tlen.pl> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Borislav Petkov <bbpetkov@yahoo.de> Cc: Robert Hancock <hancockrwd@gmail.com> Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com> Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-08-12pata_at91: fix resource releaseTejun Heo
Julias Lawall discovered that pata_at91 wasn't freeing a memory region allocated with kzalloc() on init failure paths. Upon review, pata_at91 also seems to be doing unnecessary explicit resource releases for managed resources too. Convert memory allocation to managed one and drop unnecessary explicit resource releases. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Julia Lawall <julia@diku.dk> Cc: Sergey Matyukevich <geomatsi@gmail.com> Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2009-08-12xfs: fix spin_is_locked assert on uni-processor buildsChristoph Hellwig
Without SMP or preemption spin_is_locked always returns false, so we can't do an assert with it. Instead use assert_spin_locked, which does the right thing on all builds. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Eric Sandeen <sandeen@sandeen.net> Reported-by: Johannes Engel <jcnengel@googlemail.com> Tested-by: Johannes Engel <jcnengel@googlemail.com> Signed-off-by: Felix Blyakher <felixb@sgi.com>
2009-08-12xfs: check for dinode realtime flag corruptionChristoph Hellwig
Ramon tested XFS with a modified version of fsfuzzer and hit a NULL pointer dereference in __xfs_get_blocks due to the RT device target pointer being NULL. To fix this reject inode with the realtime bit set on a a filesystem without an RT subvolume during inode read. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Eric Sandeen <sandeen@sandeen.net> Reviewed-by: Felix Blyakher <felixb@sgi.com> Reported-by: Ramon de Carvalho Valle <ramon@risesecurity.org> Tested-by: Ramon de Carvalho Valle <ramon@risesecurity.org> Signed-off-by: Felix Blyakher <felixb@sgi.com>
2009-08-12use XFS_CORRUPTION_ERROR in xfs_btree_check_sblockEric Sandeen
In Red Hat Bug 512552 - Can't write to XFS mount during raid5 resync a user ran into corruption while resyncing a raid, and we failed a consistency test, but didn't get much more info; it'd be nice to call XFS_CORRUPTION_ERROR here so we can see the buffer contents. Signed-off-by: Eric Sandeen <sandeen@sandeen.net> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Felix Blyakher <felixb@sgi.com>
2009-08-12xfs: switch to NOFS allocation under i_lock in xfs_attr_rmtval_getChristoph Hellwig
xfs_attr_rmtval_get is always called with i_lock held, but i_lock is taken in reclaim context so all allocations under it must avoid recursions into the filesystem. Reported by the new reclaim context tracing in lockdep. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Felix Blyakher <felixb@sgi.com> Signed-off-by: Felix Blyakher <felixb@sgi.com>
2009-08-12xfs: switch to NOFS allocation under i_lock in xfs_readlink_bmapChristoph Hellwig
xfs_readlink_bmap is called with i_lock held, but i_lock is taken in reclaim context so all allocations under it must avoid recursions into the filesystem. Reported by the new reclaim context tracing in lockdep. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Felix Blyakher <felixb@sgi.com> Signed-off-by: Felix Blyakher <felixb@sgi.com>
2009-08-12xfs: switch to NOFS allocation under i_lock in xfs_attr_rmtval_setChristoph Hellwig
xfs_attr_rmtval_set is always called with i_lock held, and i_lock is taken in reclaim context so all allocations under it must avoid recursions into the filesystem. Reported by the new reclaim context tracing in lockdep. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Felix Blyakher <felixb@sgi.com> Signed-off-by: Felix Blyakher <felixb@sgi.com>
2009-08-12xfs: switch to NOFS allocation under i_lock in xfs_buf_associate_memoryChristoph Hellwig
xfs_buf_associate_memory is used for setting up the spare buffer for the log wrap case in xlog_sync which can happen under i_lock when called from xfs_fsync. The i_lock mutex is taken in reclaim context so all allocations under it must avoid recursions into the filesystem. There are a couple more uses of xfs_buf_associate_memory in the log recovery code that are also affected by this, but I'd rather keep the code simple than passing on a gfp_mask argument. Longer term we should just stop requiring the memoery allocation in xlog_sync by some smaller rework of the buffer layer. Reported by the new reclaim context tracing in lockdep. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Felix Blyakher <felixb@sgi.com> Signed-off-by: Felix Blyakher <felixb@sgi.com>
2009-08-12xfs: switch to NOFS allocation under i_lock in xfs_dir_cilookup_resultChristoph Hellwig
xfs_dir_cilookup_result is always called with i_lock held, but i_lock is taken in reclaim context so all allocations under it must avoid recursions into the filesystem. Reported by the new reclaim context tracing in lockdep. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Felix Blyakher <felixb@sgi.com> Signed-off-by: Felix Blyakher <felixb@sgi.com>
2009-08-12xfs: switch to NOFS allocation under i_lock in xfs_da_buf_makeChristoph Hellwig
i_lock is taken in the reclaim context so all allocations under it must avoid recursions into the filesystem. Reported by the new reclaim context tracing in lockdep. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Felix Blyakher <felixb@sgi.com> Signed-off-by: Felix Blyakher <felixb@sgi.com>
2009-08-12xfs: switch to NOFS allocation under i_lock in xfs_da_state_allocChristoph Hellwig
xfs_da_state_alloc is always called with i_lock held, but i_lock is taken in reclaim context so all allocations under it must avoid recursions into the filesystem. Reported by the new reclaim context tracing in lockdep. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Felix Blyakher <felixb@sgi.com> Signed-off-by: Felix Blyakher <felixb@sgi.com>
2009-08-12xfs: switch to NOFS allocation under i_lock in xfs_getbmapChristoph Hellwig
xfs_getbmap allocates memory with i_lock held, but i_lock is taken in reclaim context so all allocations under it must avoid recursions into the filesystem. Reported by the new reclaim context tracing in lockdep. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Felix Blyakher <felixb@sgi.com> Signed-off-by: Felix Blyakher <felixb@sgi.com>
2009-08-12xfs: avoid memory allocation under m_peraglock in growfs codeChristoph Hellwig
Allocate the memory for the larger m_perag array before taking the per-AG lock as the per-AG lock can be taken under the i_lock which can be taken from reclaim context. Reported by the new reclaim context tracing in lockdep. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Felix Blyakher <felixb@sgi.com> Signed-off-by: Felix Blyakher <felixb@sgi.com>