Roland McGrath [Thu, 10 Apr 2008 22:38:45 +0000 (15:38 -0700)]
asmlinkage_protect sys_io_getevents
Use asmlinkage_protect in sys_io_getevents, because GCC for i386 with
CONFIG_FRAME_POINTER=n can decide to clobber an argument word on the
stack, i.e. the user struct pt_regs. Here the problem is not a tail
call, but just the compiler's use of the stack when it inlines and
optimizes the body of the called function. This seems to avoid it.
Signed-off-by: Roland McGrath <roland@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Roland McGrath [Thu, 10 Apr 2008 22:37:38 +0000 (15:37 -0700)]
asmlinkage_protect replaces prevent_tail_call
The prevent_tail_call() macro works around the problem of the compiler
clobbering argument words on the stack, which for asmlinkage functions
is the caller's (user's) struct pt_regs. The tail/sibling-call
optimization is not the only way that the compiler can decide to use
stack argument words as scratch space, which we have to prevent.
Other optimizations can do it too.
Until we have new compiler support to make "asmlinkage" binding on the
compiler's own use of the stack argument frame, we have work around all
the manifestations of this issue that crop up.
More cases seem to be prevented by also keeping the incoming argument
variables live at the end of the function. This makes their original
stack slots attractive places to leave those variables, so the compiler
tends not clobber them for something else. It's still no guarantee, but
it handles some observed cases that prevent_tail_call() did not.
Signed-off-by: Roland McGrath <roland@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch also resolves hangs on boot:
http://lkml.org/lkml/2008/2/23/263
http://bugzilla.kernel.org/show_bug.cgi?id=10093
The bug was causing once-in-few-reboots 10-15 sec wait during boot on
certain laptops.
Earlier commit 40d6a146629b98d8e322b6f9332b182c7cbff3df added
smp_call_function in cpu_idle_wait() to kick cpus that are in tickless
idle. Looking at cpu_idle_wait code at that time, code seemed to be
over-engineered for a case which is rarely used (while changing idle
handler).
Below is a simplified version of cpu_idle_wait, which just makes a dummy
smp_call_function to all cpus, to make them come out of old idle handler
and start using the new idle handler. It eliminates code in the idle
loop to handle cpu_idle_wait.
David Howells [Thu, 10 Apr 2008 15:11:05 +0000 (16:11 +0100)]
FRV: Don't make smp_{r, w, }mb() interpolate MEMBAR when CONFIG_SMP=n [try #2]
Don't make smp_{r,w,}mb() interpolate a MEMBAR instruction when CONFIG_SMP=n as
SMP memory barries on UP systems should interpolate a compiler barrier only.
Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Howells [Thu, 10 Apr 2008 15:11:00 +0000 (16:11 +0100)]
FRV: Make NOMMU-mode work with base addresses other than 0xC0000000 [try #2]
Make NOMMU-mode work with base addresses other than 0xC0000000 by:
(1) Giving the code that sets up the protection registers the right address
in __sdram_base. Rather than being hard coded to 0xC0000000, the value
of __page_offset is obtained from the linker script.
(2) Eliminate the check in __switch_to() that verifies the current thread
info is in the 0xCxxxxxxx region.
Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Howells [Thu, 10 Apr 2008 15:10:45 +0000 (16:10 +0100)]
FRV: Handle update_mmu_cache() being called when current->mm is NULL [try #2]
Handle update_mmu_cache() being called when current->mm is NULL.
We cache static TLB mappings for the current page table in DAMPR4 and DAMPR5
on the theory that the next data lookup is likely to be in the same general
region, and thus is likely to be mapped by the same page table. However, we
can't get this information if we can't access the appropriate mm_struct.
If current->mm is NULL, we just clear the cache in the knowledge that the TLB
miss handlers will load it.
Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge branch 'for-linus' of git://oss.sgi.com:8090/xfs/xfs-2.6
* 'for-linus' of git://oss.sgi.com:8090/xfs/xfs-2.6:
[XFS] Ensure "both" features2 slots are consistent
[XFS] Fix superblock features2 field alignment problem
[XFS] remove shouting-indirection macros from xfs_sb.h
Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
cfq-iosched: do not leak ioc_data across iosched switches
splice: fix infinite loop in generic_file_splice_read()
Roman Zippel [Wed, 9 Apr 2008 15:44:07 +0000 (17:44 +0200)]
HFS+: fix unlink of links
Some time ago while attempting to handle invalid link counts, I botched
the unlink of links itself, so this patch fixes this now correctly, so
that only the link count of nodes that don't point to links is ignored.
Thanks to Vlado Plaga <rechner@vlado-do.de> to notify me of this
problem.
Signed-off-by: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
cfq-iosched: do not leak ioc_data across iosched switches
When switching scheduler from cfq, cfq_exit_queue() does not clear
ioc->ioc_data, leaving a dangling pointer that can deceive the following
lookups when the iosched is switched back to cfq. The pattern that can
trigger that is the following:
- elevator switch from cfq to something else;
- module unloading, with elv_unregister() that calls cfq_free_io_context()
on ioc freeing the cic (via the .trim op);
- module gets reloaded and the elevator switches back to cfq;
- reallocation of a cic at the same address as before (with a valid key).
To fix it just assign NULL to ioc_data in __cfq_exit_single_io_context(),
that is called from the regular exit path and from the elevator switching
code. The only path that frees a cic and is not covered is the error handling
one, but cic's freed in this way are never cached in ioc_data.
Eric Sandeen [Thu, 10 Apr 2008 02:19:34 +0000 (12:19 +1000)]
[XFS] Ensure "both" features2 slots are consistent
Since older kernels may look in the sb_bad_features2 slot for flags,
rather than zeroing it out on fixup, we should make it equal to the
sb_features2 value.
Also, if the ATTR2 flag was not found prior to features2 fixup, it was not
set in the mount flags, so re-check after the fixup so that the current
session will use the feature.
Also fix up the comments to reflect these changes.
David Chinner [Thu, 6 Mar 2008 02:45:50 +0000 (13:45 +1100)]
[XFS] Fix superblock features2 field alignment problem
Due to the xfs_dsb_t structure not being 64 bit aligned, the last field of
the on-disk superblock can vary in location This causes problems when the
filesystem gets moved to a different platform, or there is a 32 bit
userspace and 64 bit kernel.
This patch detects the defect at mount time, logs a warning such as:
XFS: correcting sb_features alignment problem
in dmesg and corrects the problem so that everything is OK. it also
blacklists the bad field in the superblock so it does not get used for
something else later on.
splice: fix infinite loop in generic_file_splice_read()
There's a quirky loop in generic_file_splice_read() that could go
on indefinitely, if the file splice returns 0 permanently (and not
just as a temporary condition). Get rid of the loop and pass
back -EAGAIN correctly from __generic_file_splice_read(), so we
handle that condition properly as well.
Steven Rostedt [Wed, 9 Apr 2008 23:04:07 +0000 (19:04 -0400)]
pop previous section in alternative.c
gcc expects all toplevel assembly to return to the original section type.
The code in alteranative.c does not do this. This caused some strange bugs
in sched-devel where code would end up in the .rodata section and when
the kernel sets the NX bit on all .rodata, the kernel would crash when
executing this code.
This patch adds a .previous marker to return the code back to the
original section.
Credit goes to Andrew Pinski for telling me it wasn't a gcc bug but a
bug in the toplevel asm code in the kernel. ;-)
Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Eric Paris [Wed, 9 Apr 2008 18:08:35 +0000 (14:08 -0400)]
SELinux: don't BUG if fs reuses a superblock
I (wrongly) assumed that nfs_xdev_get_sb() would not ever share a superblock
and so cloning mount options would always be correct. Turns out that isn't
the case and we could fall over a BUG_ON() that wasn't a BUG at all. Since
there is little we can do to reconcile different mount options this patch
just leaves the sb alone and the first set of options wins.
Signed-off-by: Eric Paris <eparis@redhat.com> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: Trond Myklebust <trond.myklebust@fys.uio.no> Signed-off-by: James Morris <jmorris@namei.org>
Merge branch 'upstream-linus' of 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:
ata/sata_fsl: Remove unused variable in sata_fsl_probe
pata_sil680: Fix build on arch/ppc
ata/sata_fsl: Remove unused variable in sata_fsl_probe
In sata_fsl_probe memory is allocated but never used or deallocated. Fixes: http://bugzilla.kernel.org/show_bug.cgi?id=10404
Thanks to Daniel Marjamäki for the bug report.
Reported-by: Daniel Marjamäki <danielm77@spray.se> Signed-off-by: Johann Felix Soden <johfel@users.sourceforge.net> Signed-off-by: Jeff Garzik <jeff@garzik.org>
Merge branch 'hotfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6
* 'hotfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6:
SUNRPC: Fix a memory leak in rpc_create()
fix bug - executing FDPIC ELF on NFS mount triggers BUG() at mm/nommu.c:862:/do_mmap_private()
NFS: initialize flags field in nfs_open_context
SUNRPC: don't call flush_dcache_page() with an invalid pointer
mtd/chips: add missing set_current_state() to cfi_{amdstd,staa}_sync()
cfi_amdstd_sync() and cfi_staa_sync() call schedule() without changing task's
state appropriately.
In case of e.g. chip->state == FL_ERASING, cfi_*_sync() will be busy-looping
either redundantly for a fixed interval of time (for SCHED_NORMAL tasks) or
possibly endlessly (for RT tasks and UP).
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com> Cc: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Brownell [Wed, 9 Apr 2008 00:41:58 +0000 (17:41 -0700)]
spi: documentation tweaks
Update SPI documentation to clarify some areas of recent confusion: clock
polarity takes effect when chipselect goes active; and zero length buffers are
OK in certain cases.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix bug in SPI probe: first initialize peripheral pins, and just after
register spi master device. This fixes problems with SPI drivers built-in
kernel.
Singed-off-by: Vitja Makarov <vitja.makarov@gmail.com> Signed-off-by: Bryan Wu <cooloney@kernel.org> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
acpi: fix "buggy BIOS check" when CPUs are hot removed
Fixes a BUG in ACPI hotplugging.
processor_device_array[pr->id] needs to be set to NULL when removing a CPU.
Else the "buggy BIOS check" in acpi_processor_start mistakenly fires when a
CPU is removed from the system and then later re-added.
Signed-off-by: Alok N Kataria <akataria@vmware.com> Signed-off-by: Dan Arai <arai@vmware.com> Cc: Len Brown <lenb@kernel.org> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
snd_es1968_ac97_read() calls snd_es1968_ac97_wait() first outside a locked
area, and later, while holding a lock.
snd_es1968_ac97_wait() has a polling loop with a cond_resched() inside it..
which sleeps, so the second call is invalid.
This patch adds a version of the wait function that just pure polls. While
this is not very elegant in principle, it's very likely the easiest thing to
do here, we already checked if the chip was ready (while yielding) just
before, so it is very unlikely to take a long time here.
[akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Cc: Jaroslav Kysela <perex@suse.cz> Cc: Takashi Iwai <tiwai@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
N_NORMAL_MEMORY is "true" if a node has memory for the kernel. N_HIGH_MEMORY
is "true" if a node has memory for HIGHMEM. (If CONFIG_HIGHMEM=n, always
"true")
This check is used for testing whether we can use kmalloc_node() on a node.
Then, if there is a node which only contains HIGHMEM, the system will call
kmalloc_node() which doesn't contain memory for the kernel. If it happens
under SLUB, the kernel will panic. I think this only happens on x86_32-numa.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Krzysztof Helt [Wed, 9 Apr 2008 00:41:52 +0000 (17:41 -0700)]
acpi thermal: fix result check
thermal_zone_device_register() uses the ERR_PTR macro on its return values. A
correct check is to use the IS_ERR() macro.
The 2.6.25 kernels panic on Compaq AP550 without this patch as it has more
then 10 (THERMAL_MAX_TRIPS) trip points (there are 12).
Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Len Brown <lenb@kernel.org> Acked-by: Zhang Rui <rui.zhang@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pete Zaitcev [Wed, 9 Apr 2008 00:41:51 +0000 (17:41 -0700)]
ub: remove BUG() after __blk_end_request and fix the condition causing it
When __blk_end_request returns nonzero, it means that the request was
not completely processed and some BIOs are still attached. Since we
have dequeued it by that time, it means leaking requests and hanging
processes, which is why BUG() was in there. In ub this happens if
a packet request ends normally, but with residue (e.g. when scsi_id
issues INQUIRY).
The fix is to make sure that arguments passed to __blk_end_request
are correct: the full request length and not just transferred length.
The transferred length is indicated to applications by adjusting
rq->data_len with old, unchanged code outside of this patch.
Signed-off-by: Pete Zaitcev <zaitcev@redhat.com> Cc: Kiyoshi Ueda <k-ueda@ct.jp.nec.com> Cc: Greg KH <greg@kroah.com> Cc: Boaz Harrosh <bharrosh@panasas.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Chuck Lever [Mon, 7 Apr 2008 20:52:44 +0000 (16:52 -0400)]
SUNRPC: Fix a memory leak in rpc_create()
Commit 510deb0d was supposed to move the xprt_create_transport() call in
rpc_create(), but neglected to remove the old call site. This resulted in
a transport leak after every rpc_create() call.
This leak is present in 2.6.24 and 2.6.25.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
fix bug - executing FDPIC ELF on NFS mount triggers BUG() at mm/nommu.c:862:/do_mmap_private()
NFS needs a NOMMU version mmap function to support uClinux on NOMMU machine
http://blackfin.uclinux.org/gf/project/uclinux-dist/tracker/?action=TrackerItemEdit&tracker_id=141&tracker_item_id=3992
Jeff Layton [Mon, 31 Mar 2008 19:01:58 +0000 (15:01 -0400)]
NFS: initialize flags field in nfs_open_context
The nfs_open_context struct had a "flags" field added recently, but the
allocator isn't initializing it. It also looks like the allocator isn't
initializing the mode or list either, but they seem to be overwritten
by the caller, so that's less of an issue.
Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Trond Myklebust [Mon, 31 Mar 2008 21:02:02 +0000 (17:02 -0400)]
SUNRPC: don't call flush_dcache_page() with an invalid pointer
Fix a problem in _copy_to_pages(), whereby it may call flush_dcache_page()
with an invalid pointer due to the fact that 'pgto' gets incremented
beyond the end of the page array. Fix is to exit the loop without this
unnecessary increment of pgto.
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/selinux-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/selinux-2.6:
SELinux: more GFP_NOFS fixups to prevent selinux from re-entering the fs code
Sergei Shtylyov [Mon, 7 Apr 2008 21:30:10 +0000 (23:30 +0200)]
siimage: fix kernel oops on PPC 44x
Fix kernel oops due to machine check occuring in init_chipset_siimage() on PPC
44x platforms. These 32-bit CPUs have 36-bit physical address and PCI I/O and
memory spaces are mapped beyond 4 GB; arch/ppc/ code has a fixup in ioremap()
that creates an illusion of the PCI I/O and memory resources being mapped below
4 GB, while arch/powerpc/ code got rid of this fixup with PPC 44x having instead
CONFIG_RESOURCES_64BIT=y -- this causes the resources to be truncated to 32-bit
'unsigned long' type in this driver, and so non-existant memory being ioremap'ed
and then accessed...
Thanks to Valentine Barshak for providing an initial patch and explanations.
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com> Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Anthony Liguori [Mon, 7 Apr 2008 20:33:16 +0000 (15:33 -0500)]
virtio_net: remove overzealous printk
The 'disable_cb' is really just a hint and as such, it's possible for more
work to get queued up while callbacks are disabled. Under stress with an
SMP guest, this printk triggers very frequently. There is no race here, this
is how things are designed to work so let's just remove the printk.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> Acked-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/x86/linux-2.6-x86:
x86: fix 64-bit asm NOPS for CONFIG_GENERIC_CPU
x86: fix call to set_cyc2ns_scale() from time_cpufreq_notifier()
revert "x86: tsc prevent time going backwards"
Rusty Russell [Mon, 7 Apr 2008 04:30:28 +0000 (14:30 +1000)]
virtio: remove overzealous BUG_ON.
The 'disable_cb' callback is designed as an optimization to tell the host
we don't need callbacks now. As it is not reliable, the debug check is
overzealous: it can happen on two CPUs at the same time. Document this.
Even if it were reliable, the virtio_net driver doesn't disable
callbacks on transmit so the START_USE/END_USE debugging reentrance
protection can be easily tripped even on UP.
Thanks to Balaji Rao for the bug report and testing.
ASM_NOP's for 64-bit kernel with CONFIG_GENERIC_CPU is broken
with the recent x86 nops merge. They were using GENERIC_NOPS
which will truncate the upper 32bits of %rsi, because of the missing
64bit rex prefix.
For now, fall back ASM NOPS for generic cpu to K8 NOPS, similar
to the code before the wrong x86 nop merge.
This should resolve the crash seen by Ingo on a test-system:
x86: fix call to set_cyc2ns_scale() from time_cpufreq_notifier()
In time_cpufreq_notifier() the cpu id to act upon is held in freq->cpu. Use it
instead of smp_processor_id() in the call to set_cyc2ns_scale().
This makes the preempt_*able() unnecessary and lets set_cyc2ns_scale() update
the intended cpu's cyc2ns.
Related mail/thread: http://lkml.org/lkml/2007/12/7/130
it has been identified to cause suspend regression - and the
commit fixes a longstanding bug that existed before 2.6.25 was
opened - so it can wait some more until the effects are better
understood.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
fix endian lossage in forcedeth
net/tokenring/olympic.c section fixes
net: marvell.c fix sparse shadowed variable warning
[VLAN]: Fix egress priority mappings leak.
[TG3]: Add PHY workaround for 5784
[NET]: srandom32 fixes for networking v2
[IPV6]: Fix refcounting for anycast dst entries.
[IPV6]: inet6_dev on loopback should be kept until namespace stop.
[IPV6]: Event type in addrconf_ifdown is mis-used.
[ICMP]: Ensure that ICMP relookup maintains status quo
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6:
[SPARC64]: Fix user accesses in regset code.
[SPARC64]: Fix FPU saving in 64-bit signal handling.
Merge branch 'pci_id_updates' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/v4l-dvb
* 'pci_id_updates' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/v4l-dvb:
V4L/DVB (7497): pvrusb2: add new usb pid for 73xxx models
V4L/DVB (7496): pvrusb2: add new usb pid for 75xxx models
Rusty Russell [Sun, 6 Apr 2008 07:23:38 +0000 (17:23 +1000)]
Fix booting pentium+ with dodgy TSC
We handle a broken tsc these days, so no need to panic. We clear the
TSC bit when tsc_init decides it's unreliable (eg. under lguest w/ bad
host TSC), leading to bogus panic.
Now that we're mapping registers in the DRM driver at load time, the
driver actually checks the PCI ID, so we need to make sure the macros
have all the right bits (and longer term use the DRM headers as the sole
copy of the PCI & register definitions).
This patch adds 945GME support to the DRM headers, fixing a regression
reported in http://bugzilla.kernel.org/show_bug.cgi?id=10395.
Since 2.6.25-rc7, I've been seeing an occasional livelock on one x86_64
machine, copying kernel trees to tmpfs, paging out to swap.
Signature: 6000 pages under writeback but never getting written; most
tasks of interest trying to reclaim, but each get_swap_bio waiting for a
bio in mempool_alloc's io_schedule_timeout(5*HZ); every five seconds an
atomic page allocation failure report from kblockd failing to allocate a
sense_buffer in __scsi_get_command.
__scsi_get_command has a (one item) free_list to protect against this,
but rc1's [SCSI] use dynamically allocated sense buffer de25deb18016f66dcdede165d07654559bb332bc upset that slightly. When it
fails to allocate from the separate sense_slab, instead of giving up, it
must fall back to the command free_list, which is sure to have a
sense_buffer attached.
Either my earlier -rc testing missed this, or there's some recent
contributory factor. One very significant factor is SLUB, which merges
slab caches when it can, and on 64-bit happens to merge both bio cache
and sense_slab cache into kmalloc's 128-byte cache: so that under this
swapping load, bios above are liable to gobble up all the slots needed
for scsi_cmnd sense_buffers below.
That's disturbing behaviour, and I tried a few things to fix it. Adding
a no-op constructor to the sense_slab inhibits SLUB from merging it, and
stops all the allocation failures I was seeing; but it's rather a hack,
and perhaps in different configurations we have other caches on the
swapout path which are ill-merged.
Another alternative is to revert the separate sense_slab, using
cache-line-aligned sense_buffer allocated beyond scsi_cmnd from the one
kmem_cache; but that might waste more memory, and is only a way of
diverting around the known problem.
While I don't like seeing the allocation failures, and hate the idea of
all those bios piled up above a scsi host working one by one, it does
seem to emerge fairly soon with the livelock fix. So lacking better
ideas, stick with that one clear fix for now.
Signed-off-by: Hugh Dickins <hugh@veritas.com> Cc: James Bottomley <James.Bottomley@HansenPartnership.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp> Cc: Jens Axboe <jens.axboe@oracle.com> Cc: Christoph Lameter <clameter@sgi.com> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: Peter Zijlstra <a.p.ziljstra@chello.nl> Cc: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Andrew Paprocki [Wed, 2 Apr 2008 06:43:19 +0000 (02:43 -0400)]
[WATCHDOG] it8712f_wdt Zero MSB timeout byte when disabling watchdog
I noticed this while testing the latest code. I'm not sure if it is required,
but the normal (or LSB) timeout value is set to zero, so the MSB should
be as well to stay consistent.
If the chip revision is >= 8, set MSB of the 16-bit timeout value to zero
when disabling the watchdog in it8712f_wdt_disable().
Signed-off-by: Andrew Paprocki <andrew@ishiboo.com> Signed-off-by: Wim Van Sebroeck <wim@iguana.be> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Revert "ACPI: Ignore _BQC object when registering backlight device"
This reverts commit 7c0ea45be4f114d85ee35caeead8e1660699c46f which
caused a regression with the backlight being set to off when a laptop
doesn't have a _BQC entry to query the actual backlight value. The code
blindly then falls back on a value of 0.
See
http://bugzilla.kernel.org/show_bug.cgi?id=10387
http://lkml.org/lkml/2008/4/2/366
for details.
Bisected-and-reported-by: Andrey Borzenkov <arvidjaar@mail.ru> Cc: Zhao Yakui <yakui.zhao@intel.com> Cc: Zhang Rui <rui.zhang@intel.com> Cc: Len Brown <len.brown@intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Carol Hebert [Fri, 4 Apr 2008 21:30:03 +0000 (14:30 -0700)]
ipmi: change device node ordering to reflect probe order
In 2.6.14 a patch was merged which switching the order of the ipmi device
naming from in-order-of-discovery over to reverse-order-of-discovery.
So on systems with multiple BMC interfaces, the ipmi device names are being
created in reverse order relative to how they are discovered on the system
(e.g. on an IBM x3950 multinode server with N nodes, the device name for the
BMC in the first node is /dev/ipmiN-1 and the device name for the BMC in the
last node is /dev/ipmi0, etc.).
The problem is caused by the list handling routines chosen in dmi_scan.c.
Using list_add() causes the multiple ipmi devices to be added to the device
list using a stack-paradigm and so the ipmi driver subsequently pulls them off
during initialization in LIFO order. This patch changes the
dmi_save_ipmi_device() list handling paradigm to a queue, thereby allowing the
ipmi driver to build the ipmi device names in the order in which they are
found on the system.
Signed-off-by: Carol Hebert <cah@us.ibm.com> Signed-off-by: Corey Minyard <cminyard@mvista.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mtd: fix broken state in CFI driver caused by FL_SHUTDOWN
THe CFI driver in 2.6.24 kernel is broken. Not so intensive read/write
operations cause incomplete writes which lead to kernel panics in JFFS2.
We investigated the issue - it is caused by bug in FL_SHUTDOWN parsing code.
Sometimes chip returns -EIO as if it is in FL_SHUTDOWN state when it should
wait in FL_PONT (error in order of conditions).
The following patch fixes the bug in state parsing code of CFI. Also I've
added comments to notify developers if they want to add new case in future.
Signed-off-by: Alexey Korolev <akorolev@infradead.org> Reviewed-by: Joern Engel <joern@logfs.org> Cc: David Woodhouse <dwmw2@infradead.org> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
memory controller: make memory resource control aware of boot options
A boot option for the memory controller was discussed on lkml. It is a good
idea to add it, since it saves memory for people who want to turn off the
memory controller.
By default the option is on for the following two reasons:
1. It provides compatibility with the current scheme where the memory
controller turns on if the config option is enabled
2. It allows for wider testing of the memory controller, once the config
option is enabled
We still allow the create, destroy callbacks to succeed, since they are not
aware of boot options. We do not populate the directory will memory resource
controller specific files.
Paul Menage [Fri, 4 Apr 2008 21:29:57 +0000 (14:29 -0700)]
cgroups: add cgroup support for enabling controllers at boot time
The effects of cgroup_disable=foo are:
- foo isn't auto-mounted if you mount all cgroups in a single hierarchy
- foo isn't visible as an individually mountable subsystem
As a result there will only ever be one call to foo->create(), at init time;
all processes will stay in this group, and the group will never be mounted on
a visible hierarchy. Any additional effects (e.g. not allocating metadata)
are up to the foo subsystem.
This doesn't handle early_init subsystems (their "disabled" bit isn't set be,
but it could easily be extended to do so if any of the early_init systems
wanted it - I think it would just involve some nastier parameter processing
since it would occur before the command-line argument parser had been run.
Hugh said:
Ballpark figures, I'm trying to get this question out rather than
processing the exact numbers: CONFIG_CGROUP_MEM_RES_CTLR adds 15% overhead
to the affected paths, booting with cgroup_disable=memory cuts that back to
1% overhead (due to slightly bigger struct page).
I'm no expert on distros, they may have no interest whatever in
CONFIG_CGROUP_MEM_RES_CTLR=y; and the rest of us can easily build with or
without it, or apply the cgroup_disable=memory patches.
Unix bench's execl test result on x86_64 was
== just after boot without mounting any cgroup fs.==
mem_cgorup=off : Execl Throughput 43.0 3150.1 732.6
mem_cgroup=on : Execl Throughput 43.0 2932.6 682.0
==
Sergei Shtylyov [Thu, 20 Mar 2008 17:59:34 +0000 (20:59 +0300)]
[MIPS] Make KGDB compile on UP
Building UP kernel with KGDB enabled produces the following errors and warning
(fatal due to -Werror in arch/mips/kernel/Makefile):
In file included from arch/mips/kernel/gdb-stub.c:142:
include/asm/smp.h:25:1: "raw_smp_processor_id" redefined
In file included from include/linux/sched.h:69,
from arch/mips/kernel/gdb-stub.c:126:
include/linux/smp.h:88:1: this is the location of the previous definition
In file included from arch/mips/kernel/gdb-stub.c:142:
include/asm/smp.h:62: error: redefinition of 'smp_send_reschedule'
include/linux/smp.h:102: error: previous definition of 'smp_send_reschedule' was here
include/asm/smp.h: In function `smp_send_reschedule':
include/asm/smp.h:65: error: dereferencing pointer to incomplete type
arch/mips/kernel/gdb-stub.c: At top level:
arch/mips/kernel/gdb-stub.c:660: warning: 'kgdb_wait' defined but not used
Fix the errors by not directly including <asm/smp.h> (which is already included
by <linux/smp.h>) and the warning by enclosing kgdb_wait() in #ifdef CONFIG_SMP.
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com> Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Adrian Bunk [Fri, 4 Apr 2008 12:57:38 +0000 (14:57 +0200)]
m68k: use KBUILD_DEFCONFIG
The default defconfig should be one from arch/m68k/configs/
arch/m68k/defconfig was not exactly identical to amiga_defconfig but
also considering how long they have been without any update that doesn't
seem to have been on purpose.
Merge branch 'upstream-linus' of 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:
pata_ali: disable ATAPI DMA
libata: ATA_12/16 doesn't fall into ATAPI_MISC
libata: uninline atapi_cmd_type()
libata: fix IDENTIFY order in ata_bus_probe()
Mikulas Patocka noted that the optimization where we check if a buffer
was already dirty (and we avoid re-dirtying it) was not really SMP-safe.
Since the read of the old status was not synchronized with anything, an
aggressive CPU re-ordering of memory accesses might have moved that read
up to before the data was even written to the buffer, and another CPU
that cleaned it again, causing the newly dirty state to never actually
hit the disk.
Admittedly this would probably never trigger in practice, but it's still
wrong.
Mikulas sent a patch that fixed the problem, but I dislike the subtlety
of the whole optimization, so this is an alternate fix that is more
explicit about the particular SMP ordering for the optimization, and
separates out the speculative reads of the buffer state into its own
conditional (and makes the memory barrier only happen if we are likely
to actually hit the optimized case in the first place).
I considered removing the optimization entirely, but Andrew argued for
it's continued existence. I'm a push-over.
parport_pc: make sure to release IO ports after probing for IT87XX
Commit f63fd7e299ee13da071ecfce2b90b58c5e1562b1 ("parport_pc: detection
for SuperIO IT87XX POST") only released the IO port region on success,
not when the probe for the IT87XX chip failed.
That caused not only a reserved region to leak, but also caused an oops
when the driver module was unloaded and somebody tried to cat
/proc/ioports - because the string that was assigned to the IO port
region was a static string in the module virtual address area.
Reported-by: Lubos Lunak <l.lunak@suse.cz> Cc: Jan Kara <jack@suse.cz> Cc: Petr Cvek <petr.cvek@tul.cz> Acked-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Al Viro [Wed, 26 Mar 2008 05:57:12 +0000 (05:57 +0000)]
fix endian lossage in forcedeth
a) if you initialize something with le32_to_cpu(...), then |= it
with host-endian and feed to cpu_to_le32(), it's most definitely
*not* __le32. As sparse would've told you...
b) the whole sequence is |= cpu_to_le32(host-endian constant)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Jeff Garzik <jeff@garzik.org>
have been identified to cause a regression on some platforms due to
the assignement of legacy IRQs which makes the legacy devices
connected to those IRQs disfunctional.
Revert them.
This fixes http://bugzilla.kernel.org/show_bug.cgi?id=10382
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Thomas Gleixner [Tue, 1 Apr 2008 17:45:18 +0000 (19:45 +0200)]
x86: tsc prevent time going backwards
We already catch most of the TSC problems by sanity checks, but there
is a subtle bug which has been in the code for ever. This can cause
time jumps in the range of hours.
This was reported in:
http://lkml.org/lkml/2007/8/23/96
and
http://lkml.org/lkml/2008/3/31/23
I was able to reproduce the problem with a gettimeofday loop test on a
dual core and a quad core machine which both have sychronized
TSCs. The TSCs seems not to be perfectly in sync though, but the
kernel is not able to detect the slight delta in the sync check. Still
there exists an extremly small window where this delta can be observed
with a real big time jump. So far I was only able to reproduce this
with the vsyscall gettimeofday implementation, but in theory this
might be observable with the syscall based version as well.
CPU 0 updates the clock source variables under xtime/vyscall lock and
CPU1, where the TSC is slighty behind CPU0, is reading the time right
after the seqlock was unlocked.
The clocksource reference data was updated with the TSC from CPU0 and
the value which is read from TSC on CPU1 is less than the reference
data. This results in a huge delta value due to the unsigned
subtraction of the TSC value and the reference value. This algorithm
can not be changed due to the support of wrapping clock sources like
pm timer.
The huge delta is converted to nanoseconds and added to xtime, which
is then observable by the caller. The next gettimeofday call on CPU1
will show the correct time again as now the TSC has advanced above the
reference value.
To prevent this TSC specific wreckage we need to compare the TSC value
against the reference value and return the latter when it is larger
than the actual TSC value.
I pondered to mark the TSC unstable when the readout is smaller than
the reference value, but this would render an otherwise good and fast
clocksource unusable without a real good reason.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
fix memory corruption and crash due to mis-sized grant table.
A PV OS has two grant table data structures: the grant table itself
and a free list. The free list is composed of an array of pages,
which grow dynamically as the guest OS requires more grants. While
the grant table contains 8-byte entries, the free list contains 4-byte
entries. So we have half as many pages in the free list than in the
grant table.
There was a bug in the free list allocation code. The free list was
indexed as if it was the same size as the grant table. But it's only
half as large. So memory got corrupted, and I was seeing crashes in
the slab allocator later on.
25-rc* stopped working with CONFIG_X86_VSMP on vSMP machines.
Looks like the vsmp irq ops got accidentally removed during merge of x86_64
pvops in 2.6.25. -- commit 6abcd98ffafbff81f0bfd7ee1d129e634af13245 removed
vsmp irq ops.
Tested with both CONFIG_X86_VSMP and without CONFIG_X86_VSMP, on vSMP and non
vSMP x86_64 machines.
ATAPI DMA just doesn't work reliably on pata_ali. The IDE driver can
do it but for some mysterious reason, pata_ali can't. This patch
disables it by default and makes the driver whine during
initialization. "pata_ali.atapi_dma" parameter is added so that user
can bypass the workaround.
Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
SAT passthrus don't really fit into ATAPI_MISC class. SAT passthru
commands always transfer multiple of 512 bytes and variable length
response is not allowed. This patch creates a separate category -
ATAPI_PASS_THRU - for these.
This fixes HSM violation on "hdparm -I".
Signed-off-by: Tejun Heo <htejun@gmail.com> Signed-off-by: Jeff Garzik <jeff@garzik.org>
Matt Carlson [Fri, 4 Apr 2008 04:44:44 +0000 (21:44 -0700)]
[TG3]: Add PHY workaround for 5784
The 5784 B step and newer chips require the PHY DSPs to be fine-tuned
based on one-time programmable values stored in the chip. This is
essential to achieve optimal PHY operations especially when using
long cables. We also need to properly handle the 10Mbit RX bit in the
CPMU_CTRL register during PHY reset.
Update version to 3.89.
Signed-off-by: Matt Carlson <mcarlson@broadcom.com> Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
projects / linux-2.6 / log