Amit Shah [Wed, 16 Mar 2011 13:42:10 +0000 (19:12 +0530)]
virtio: Decrement avail idx on buffer detach
When detaching a buffer from a vq, the avail.idx value should be
decremented as well.
This was noticed by hot-unplugging a virtio console port and then
plugging in a new one on the same number (re-using the vqs which were
just 'disowned'). qemu reported
'Guest moved used index from 0 to 256'
when any IO was attempted on the new port.
CC: stable@kernel.org Reported-by: juzhang <juzhang@redhat.com> Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Merge branch 'for-2.6.39' of git://linux-nfs.org/~bfields/linux
* 'for-2.6.39' of git://linux-nfs.org/~bfields/linux:
Open with O_CREAT flag set fails to open existing files on non writable directories
nfsd4: Fix filp leak
nfsd4: fix struct file leak on delegation
Merge branch 'fixes' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'fixes' of master.kernel.org:/home/rmk/linux-2.6-arm:
ARM: 6881/1: cputype.h uses __attribute_const__ which requires including kernel.h
ARM: Add new syscalls
Merge branch 'stable/bug-fixes-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
* 'stable/bug-fixes-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen: mask_rw_pte: do not apply the early_ioremap checks on x86_32
xen: do not create the extra e820 region at an addr lower than 4G
Merge branch 'for-linus' of git://neil.brown.name/md
* 'for-linus' of git://neil.brown.name/md:
md: Update documentation for sync_min and sync_max entries
md: Cleanup after raid45->raid0 takeover
md: Fix dev_sectors on takeover from raid0 to raid4/5
md/raid5: remove setting of ->queue_lock
Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
block: Remove the extra check in queue_requests_store
block, blk-sysfs: Fix an err return path in blk_register_queue()
block: remove stale kerneldoc member from __blk_run_queue()
block: get rid of QUEUE_FLAG_REENTER
cfq-iosched: read_lock() does not always imply rcu_read_lock()
block: kill blk_flush_plug_list() export
Open with O_CREAT flag set fails to open existing files on non writable directories
An open on a NFS4 share using the O_CREAT flag on an existing file for
which we have permissions to open but contained in a directory with no
write permissions will fail with EACCES.
A tcpdump shows that the client had set the open mode to UNCHECKED which
indicates that the file should be created if it doesn't exist and
encountering an existing flag is not an error. Since in this case the
file exists and can be opened by the user, the NFS server is wrong in
attempting to check create permissions on the parent directory.
The patch adds a conditional statement to check for create permissions
only if the file doesn't exist.
Signed-off-by: Sachin S. Prabhu <sprabhu@redhat.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
xen: mask_rw_pte: do not apply the early_ioremap checks on x86_32
The two "is_early_ioremap_ptep" checks in mask_rw_pte are only used on
x86_64, in fact early_ioremap is not used at all to setup the initial
pagetable on x86_32.
Moreover on x86_32 the two checks are wrong because the range
pgt_buf_start..pgt_buf_end initially should be mapped RW because
the pages in the range are not pagetable pages yet and haven't been
cleared yet. Afterwards considering the pgt_buf_start..pgt_buf_end is
part of the initial mapping, xen_alloc_pte is capable of turning
the ptes RO when they become pagetable pages.
Fix the issue and improve the readability of the code providing two
different implementation of mask_rw_pte for x86_32 and x86_64.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
xen: do not create the extra e820 region at an addr lower than 4G
Do not add the extra e820 region at a physical address lower than 4G
because it breaks e820_end_of_low_ram_pfn().
It is OK for us to move the xen_extra_mem_start up and down because this
is the index of the memory that can be ballooned in/out - it is memory
not available to the kernel during bootup.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Krzysztof Wojcik [Wed, 20 Apr 2011 05:39:53 +0000 (15:39 +1000)]
md: Cleanup after raid45->raid0 takeover
Problem:
After raid4->raid0 takeover operation, another takeover operation
(e.g raid0->raid10) results "kernel oops".
Root cause:
Variables 'degraded' in mddev structure is not cleared
on raid45->raid0 takeover.
This patch reset this variable.
Signed-off-by: Krzysztof Wojcik <krzysztof.wojcik@intel.com> Signed-off-by: NeilBrown <neilb@suse.de>
md: Fix dev_sectors on takeover from raid0 to raid4/5
A raid0 array doesn't set 'dev_sectors' as each device might
contribute a different number of sectors.
So when converting to a RAID4 or RAID5 we need to set dev_sectors
as they need the number.
We have already verified that in fact all devices do contribute
the same number of sectors, so use that number.
We previously needed to set ->queue_lock to match the raid5
device_lock so we could safely use queue_flag_* operations (e.g. for
plugging). which test the ->queue_lock is in fact locked.
However that need has completely gone away and is unlikely to come
back to remove this now-pointless setting.
Merge branch 'drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6
* 'drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6:
drm/radeon/kms: pll tweaks for r7xx
drm/nouveau: fix allocation of notifier object
drm/nouveau: fix notifier memory corruption bug
drm/nouveau: fix pinning of notifier block
drm/nouveau: populate ttm_alloced with false, when it's not
drm/nouveau: fix nv30 pcie boards
drm/nouveau: split ramin_lock into two locks, one hardirq safe
drm/radeon/kms: adjust evergreen display watermark setup
drm/radeon/kms: add connectors even if i2c fails
drm/radeon/kms: fix bad shift in atom iio table parser
Dave Airlie [Tue, 19 Apr 2011 23:21:34 +0000 (09:21 +1000)]
Merge remote branch 'nouveau/drm-nouveau-fixes' of /ssd/git/drm-nouveau-next into drm-fixes
* 'nouveau/drm-nouveau-fixes' of /ssd/git/drm-nouveau-next:
drm/nouveau: fix allocation of notifier object
drm/nouveau: fix notifier memory corruption bug
drm/nouveau: fix pinning of notifier block
drm/nouveau: populate ttm_alloced with false, when it's not
drm/nouveau: fix nv30 pcie boards
drm/nouveau: split ramin_lock into two locks, one hardirq safe
Marcin Slusarz [Tue, 19 Apr 2011 21:52:42 +0000 (23:52 +0200)]
drm/nouveau: fix allocation of notifier object
Commit 73412c3854c877e5f37ad944ee8977addde4d35a ("drm/nouveau: allocate
kernel's notifier object at end of block") intended to align end of
notifier block to page boundary, but start of block was miscalculated
to be off by -16 bytes. Fix it.
Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com> Cc: Ben Skeggs <bskeggs@redhat.com> Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Marcin Slusarz [Tue, 19 Apr 2011 21:50:48 +0000 (23:50 +0200)]
drm/nouveau: fix notifier memory corruption bug
nouveau_bo_wr32 expects offset to be in words, but we pass value in bytes,
so after commit 73412c3854c877e5f37ad944ee8977addde4d35a ("drm/nouveau: allocate
kernel's notifier object at end of block") we started to overwrite some memory
after notifier buffer object (previously m2mf_ntfy was always 0, so it didn't
matter it was a value in bytes).
Reported-by: Dominik Brodowski <linux@dominikbrodowski.net> Reported-by: Nigel Cunningham <lkml@nigelcunningham.com.au> Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com> Cc: Ben Skeggs <bskeggs@redhat.com> Cc: Pekka Paalanen <pq@iki.fi> Cc: stable@kernel.org [2.6.38] Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Ben Skeggs [Fri, 8 Apr 2011 00:07:34 +0000 (10:07 +1000)]
drm/nouveau: fix nv30 pcie boards
Wasn't aware they even existed, apparently they do! They're actually
AGP chips with a bridge as far as I can tell, which puts them in the
same boat as nv40/nv45.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (51 commits)
netfilter: ipset: Fix the order of listing of sets
ip6_pol_route panic: Do not allow VLAN on loopback
bnx2x: Fix port identification problem
r8169: add Realtek as maintainer.
ip: ip_options_compile() resilient to NULL skb route
bna: fix memory leak during RX path cleanup
bna: fix for clean fw re-initialization
usbnet: Fix up 'FLAG_POINTTOPOINT' and 'FLAG_MULTI_PACKET' overlaps.
iwlegacy: fix tx_power initialization
Revert "tcp: disallow bind() to reuse addr/port"
qlcnic: limit skb frags for non tso packet
net: can: mscan: fix build breakage in mpc5xxx_can
netfilter: ipset: set match and SET target fixes
netfilter: ipset: bitmap:ip,mac type requires "src" for MAC
sctp: fix oops while removed transport still using as retran path
sctp: fix oops when updating retransmit path with DEBUG on
net: Disable NETIF_F_TSO_ECN when TSO is disabled
net: Disable all TSO features when SG is disabled
sfc: Use rmb() to ensure reads occur in order
ieee802154: Remove hacked CFLAGS in net/ieee802154/Makefile
...
The above patch breaks free path for stp->st_file. If stp was inserted
into sop->so_stateids, we have to free stp->st_file refcount. Because
stp->st_file refcount itself is taken whether or not any refcounts are
taken on the stp->st_file->fi_fds[].
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: stable@kernel.org Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
PCI: pci-label: Fix build failure when CONFIG_NLS is set to 'm' by allmodconfig
Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
x86, gart: Make sure GART does not map physmem above 1TB
x86, gart: Set DISTLBWALKPRB bit always
x86, gart: Convert spaces to tabs in enable_gart_translation
Merge branch 'timer-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'timer-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
RTC: rtc-omap: Fix a leak of the IRQ during init failure
posix clocks: Replace mutex with reader/writer semaphore
Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
perf, x86: Fix AMD family 15h FPU event constraints
perf, x86: Fix pre-defined cache-misses event for AMD family 15h cpus
perf evsel: Fix use of inherit
perf hists browser: Fix seg fault when annotate null symbol
Quoth Jiri Slaby:
"It fixes mmap when IOMMU is used on x86 only, but breaks architectures
like ARM or PPC where virt_to_phys(dma_alloc_coherent) doesn't work.
We need there dma_mmap_coherent or similar (the trickery what
snd_pcm_default_mmap does but in some saner way). But this cannot be
done at this phase."
Requested-by: Jiri Slaby <jslaby@suse.cz> Cc: Russell King - ARM Linux <linux@arm.linux.org.uk> Cc: Janusz Krzysztofik <jkrzyszt@tis.icnet.pl> Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-fixes:
GFS2: filesystem hang caused by incorrect lock order
GFS2: Don't try to deallocate unlinked inodes when mounted ro
GFS2: directly write blocks past i_size
GFS2: write_end error path fails to unlock transaction lock
MAX34440 and MAX34441 have their own driver, thus there should be explicit
documentation instead of mentioning the chips in the generic PMBus driver
documentation.
Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com> Reviewed-by: Tom Grennan <tom.grennan@ericsson.com>
hwmon: Add submitting-patches checklist to documentation
When writing hardware monitoring drivers, there are some common pitfalls which
keep coming up in code reviews. This patch provides a document describing all
those pitfalls and how to avoid them.
Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com> Acked-by: Jean Delvare <khali@linux-fr.org>
netfilter: ipset: Fix the order of listing of sets
A restoreable saving of sets requires that list:set type of sets
come last and the code part which should have taken into account
the ordering was broken. The patch fixes the listing order.
Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu> Signed-off-by: Patrick McHardy <kaber@trash.net>
Tao Ma [Tue, 19 Apr 2011 11:50:40 +0000 (13:50 +0200)]
block: Remove the extra check in queue_requests_store
In queue_requests_store, the code looks like
if (rl->count[BLK_RW_SYNC] >= q->nr_requests) {
blk_set_queue_full(q, BLK_RW_SYNC);
} else if (rl->count[BLK_RW_SYNC]+1 <= q->nr_requests) {
blk_clear_queue_full(q, BLK_RW_SYNC);
wake_up(&rl->wait[BLK_RW_SYNC]);
}
If we don't satify the situation of "if", we can get that
rl->count[BLK_RW_SYNC} < q->nr_quests. It is the same as
rl->count[BLK_RW_SYNC]+1 <= q->nr_requests.
All the "else" should satisfy the "else if" check so it isn't
needed actually.
Signed-off-by: Tao Ma <boyu.mt@taobao.com> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
We are currently using this flag to check whether it's safe
to call into ->request_fn(). If it is set, we punt to kblockd.
But we get a lot of false positives and excessive punts to
kblockd, which hurts performance.
The only real abuser of this infrastructure is SCSI. So export
the async queue run and convert SCSI over to use that. There's
room for improvement in that SCSI need not always use the async
call, but this fixes our performance issue and they can fix that
up in due time.
Andre Przywara [Sat, 16 Apr 2011 00:27:53 +0000 (02:27 +0200)]
perf, x86: Fix pre-defined cache-misses event for AMD family 15h cpus
With AMD cpu family 15h a unit mask was introduced for the Data Cache
Miss event (0x041/L1-dcache-load-misses). We need to enable bit 0
(first data cache miss or streaming store to a 64 B cache line) of
this mask to proper count data cache misses.
Now we set this bit for all families and models. In case a PMU does
not implement a unit mask for event 0x041 the bit is ignored.
cfq-iosched: read_lock() does not always imply rcu_read_lock()
For some configurations of CONFIG_PREEMPT that is not true. So
get rid of __call_for_each_cic() and always uses the explicitly
rcu_read_lock() protected call_for_each_cic() instead.
This fixes a potential bug related to IO scheduler removal or
online switching.
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: xen-kbdfront - fix mouse getting stuck after save/restore
Input: estimate number of events per packet
Input: evdev - indicate buffer overrun with SYN_DROPPED
Input: document event types and codes and their intended use
Input: add KEY_IMAGES specifically for AL Image Browser
Input: twl4030_keypad - fix potential NULL dereference in twl4030_kp_probe()
Input: h3600_ts - fix error handling at connect
Input: twl4030_keypad - avoid potential NULL-pointer dereference
Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
block: add blk_run_queue_async
block: blk_delay_queue() should use kblockd workqueue
md: fix up raid1/raid10 unplugging.
md: incorporate new plugging into raid5.
md: provide generic support for handling unplug callbacks.
md - remove old plugging code.
md/dm - remove remains of plug_fn callback.
md: use new plugging interface for RAID IO.
block: drop queue lock before calling __blk_run_queue() for kblockd punt
Revert "block: add callback function for unplug notification"
block: Enhance new plugging support to support general callbacks
Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
powerpc/powermac: Build fix with SMP and CPU hotplug
powerpc/perf_event: Skip updating kernel counters if register value shrinks
powerpc: Don't write protect kernel text with CONFIG_DYNAMIC_FTRACE enabled
powerpc: Fix oops if scan_dispatch_log is called too early
powerpc/pseries: Use a kmem cache for DTL buffers
powerpc/kexec: Fix regression causing compile failure on UP
powerpc/85xx: disable Suspend support if SMP enabled
powerpc/e500mc: Remove CPU_FTR_MAYBE_CAN_NAP/CPU_FTR_MAYBE_CAN_DOZE
powerpc/book3e: Fix CPU feature handling on 64-bit e5500
powerpc: Check device status before adding serial device
powerpc/85xx: Don't add disabled PCIe devices
* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: (24 commits)
Btrfs: fix free space cache leak
Btrfs: avoid taking the chunk_mutex in do_chunk_alloc
Btrfs end_bio_extent_readpage should look for locked bits
Btrfs: don't force chunk allocation in find_free_extent
Btrfs: Check validity before setting an acl
Btrfs: Fix incorrect inode nlink in btrfs_link()
Btrfs: Check if btrfs_next_leaf() returns error in btrfs_real_readdir()
Btrfs: Check if btrfs_next_leaf() returns error in btrfs_listxattr()
Btrfs: make uncache_state unconditional
btrfs: using cached extent_state in set/unlock combinations
Btrfs: avoid taking the trans_mutex in btrfs_end_transaction
Btrfs: fix subvolume mount by name problem when default mount subvolume is set
fix user annotation in ioctl.c
Btrfs: check for duplicate iov_base's when doing dio reads
btrfs: properly handle overlapping areas in memmove_extent_buffer
Btrfs: fix memory leaks in btrfs_new_inode()
Btrfs: check for duplicate iov_base's when doing dio reads
Btrfs: reuse the extent_map we found when calling btrfs_get_extent
Btrfs: do not use async submit for small DIO io's
Btrfs: don't split dio bios if we don't have to
...
next_pidmap() just quietly accepted whatever 'last' pid that was passed
in, which is not all that safe when one of the users is /proc.
Admittedly the proc code should do some sanity checking on the range
(and that will be the next commit), but that doesn't mean that the
helper functions should just do that pidmap pointer arithmetic without
checking the range of its arguments.
So clamp 'last' to PID_MAX_LIMIT. The fact that we then do "last+1"
doesn't really matter, the for-loop does check against the end of the
pidmap array properly (it's only the actual pointer arithmetic overflow
case we need to worry about, and going one bit beyond isn't going to
overflow).
[ Use PID_MAX_LIMIT rather than pid_max as per Eric Biederman ]
Reported-by: Tavis Ormandy <taviso@cmpxchg8b.com> Analyzed-by: Robert Święcki <robert@swiecki.net> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Igor Mammedov [Mon, 18 Apr 2011 17:17:17 +0000 (10:17 -0700)]
Input: xen-kbdfront - fix mouse getting stuck after save/restore
Mouse gets "stuck" after restore of PV guest but buttons are in working
condition.
If driver has been configured for ABS coordinates at start it will get
XENKBD_TYPE_POS events and then suddenly after restore it'll start getting
XENKBD_TYPE_MOTION events, that will be dropped later and they won't get
into user-space.
Regression was introduced by hunk 5 and 6 of 5ea5254aa0ad269cfbd2875c973ef25ab5b5e9db
("Input: xen-kbdfront - advertise either absolute or relative
coordinates").
Driver on restore should ask xen for request-abs-pointer again if it is
available. So restore parts that did it before 5ea5254.
Acked-by: Olaf Hering <olaf@aepfle.de> Signed-off-by: Igor Mammedov <imammedo@redhat.com>
[v1: Expanded the commit description] Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
The DISTLBWALKPRB bit must be set for the GART because the
gatt table is mapped UC. But the current code does not set
the bit at boot when the BIOS setup the aperture correctly.
Fix that by setting this bit when enabling the GART instead
of the other places.
Bob Peterson [Thu, 17 Mar 2011 20:19:58 +0000 (16:19 -0400)]
GFS2: filesystem hang caused by incorrect lock order
This patch fixes a deadlock in GFS2 where two processes are trying
to reclaim an unlinked dinode:
One holds the inode glock and calls gfs2_lookup_by_inum trying to look
up the inode, which it can't, due to I_FREEING. The other has set
I_FREEING from vfs and is at the beginning of gfs2_delete_inode
waiting for the glock, which is held by the first. The solution is to
add a new non_block parameter to the gfs2_iget function that causes it
to return -ENOENT if the inode is being freed.
Signed-off-by: Bob Peterson <rpeterso@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
GFS2 was relying on the writepage code to write out the zeroed data for
fallocate. However, with FALLOC_FL_KEEP_SIZE set, this may be past i_size.
If it is, it will be ignored. To work around this, gfs2 now calls
write_dirty_buffer directly on the buffer_heads when FALLOC_FL_KEEP_SIZE
is set, and it's writing past i_size.
This version is just a cleanup of my last version
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Bob Peterson [Wed, 16 Mar 2011 20:32:39 +0000 (16:32 -0400)]
GFS2: write_end error path fails to unlock transaction lock
I did an audit of gfs2's transaction glock for bugzilla bug
658619 and ran across this:
In function gfs2_write_end, in the unlikely event that
gfs2_meta_inode_buffer returns an error, the code may forget
to unlock the transaction lock because the "failed" label
appears after the call to function gfs2_trans_end.
Signed-off-by: Bob Peterson <rpeterso@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Instead of overloading __blk_run_queue to force an offload to kblockd
add a new blk_run_queue_async helper to do it explicitly. I've kept
the blk_queue_stopped check for now, but I suspect it's not needed
as the check we do when the workqueue items runs should be enough.
Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
Richard Cochran [Wed, 30 Mar 2011 13:24:21 +0000 (15:24 +0200)]
posix clocks: Replace mutex with reader/writer semaphore
A dynamic posix clock is protected from asynchronous removal by a mutex.
However, using a mutex has the unwanted effect that a long running clock
operation in one process will unnecessarily block other processes.
For example, one process might call read() to get an external time stamp
coming in at one pulse per second. A second process calling clock_gettime
would have to wait for almost a whole second.
This patch fixes the issue by using a reader/writer semaphore instead of
a mutex.
In raid5 plugging is used for 2 things:
1/ collecting writes that require a bitmap update
2/ collecting writes in the hope that we can create full
stripes - or at least more-full.
We now release these different sets of stripes when plug_cnt
is zero.
Also in make_request, we call mddev_check_plug to hopefully increase
plug_cnt, and wake up the thread at the end if plugging wasn't
achieved for some reason.
md: provide generic support for handling unplug callbacks.
When an md device adds a request to a queue, it can call
mddev_check_plugged.
If this succeeds then we know that the md thread will be woken up
shortly, and ->plug_cnt will be non-zero until then, so some
processing can be delayed.
If it fails, then no unplug callback is expected and the make_request
function needs to do whatever is required to make the request happen.
md has some plugging infrastructure for RAID5 to use because the
normal plugging infrastructure required a 'request_queue', and when
called from dm, RAID5 doesn't have one of those available.
This relied on the ->unplug_fn callback which doesn't exist any more.
So remove all of that code, both in md and raid5. Subsequent patches
with restore the plugging functionality.
block: drop queue lock before calling __blk_run_queue() for kblockd punt
If we know we are going to punt to kblockd, we can drop the queue
lock before calling into __blk_run_queue() since it only does a
safe bit test and a workqueue call. Since kblockd needs to grab
this very lock as one of the first things it does, it's a good
optimization to drop the lock before waking kblockd.
Revert "block: add callback function for unplug notification"
MD can't use this since it really requires us to be able to
keep more than a single piece of state for the unplug. Commit 048c9374 added the required support for MD, so get rid of this
now unused code.
ip6_pol_route panic: Do not allow VLAN on loopback
Several tests in the ipv6 routing code check IFF_LOOPBACK, and
allowing stacking such as VLAN'ing on top of loopback results in a
netdevice which reports IFF_LOOPBACK but really isn't the loopback
device.
Instead of spamming the ipv6 routing code with even more special tests,
simply disallow VLAN over loopback.
The result of this patch is:
# modprobe 8021q
# vconfig add lo 43
ERROR: trying to add VLAN #43 to IF -:lo:- error: Operation not supported
Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Eric B Munson [Fri, 15 Apr 2011 08:12:30 +0000 (08:12 +0000)]
powerpc/perf_event: Skip updating kernel counters if register value shrinks
Because of speculative event roll back, it is possible for some event coutners
to decrease between reads on POWER7. This causes a problem with the way that
counters are updated. Delta calues are calculated in a 64 bit value and the
top 32 bits are masked. If the register value has decreased, this leaves us
with a very large positive value added to the kernel counters. This patch
protects against this by skipping the update if the delta would be negative.
This can lead to a lack of precision in the coutner values, but from my testing
the value is typcially fewer than 10 samples at a time.
Signed-off-by: Eric B Munson <emunson@mgebm.net> Cc: stable@kernel.org Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Stefan Roese [Thu, 14 Apr 2011 23:49:53 +0000 (23:49 +0000)]
powerpc: Don't write protect kernel text with CONFIG_DYNAMIC_FTRACE enabled
This problem was noticed on an MPC855T platform. Ftrace did oops
when trying to write to the kernel text segment.
Many thanks to Joakim for finding the root cause of this problem.
Signed-off-by: Stefan Roese <sr@denx.de> Cc: Joakim Tjernlund <joakim.tjernlund@transmode.se> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Anton Blanchard [Thu, 7 Apr 2011 21:44:21 +0000 (21:44 +0000)]
powerpc: Fix oops if scan_dispatch_log is called too early
We currently enable interrupts before the dispatch log for the boot
cpu is setup. If a timer interrupt comes in early enough we oops in
scan_dispatch_log:
Unable to handle kernel paging request for data at address 0x00000010
PAPR specifies that DTL buffers can not cross AMS environments (aka CMO
in the PAPR) and can not cross a memory entitlement granule boundary
(4k). This is found in section 14.11.3.2 H_REGISTER_VPA of the PAPR.
kmalloc does not guarantee an alignment of the allocation, though,
beyond 8 bytes (at least in my understanding). Create a special kmem
cache for DTL buffers with the alignment requirement.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Paul Gortmaker [Wed, 13 Apr 2011 06:30:08 +0000 (06:30 +0000)]
powerpc/kexec: Fix regression causing compile failure on UP
Recent commit b987812b3fcaf70fdf0037589e5d2f5f2453e6ce caused
a compile failure on UP because a considerably large block
of the file was included within CONFIG_SMP, hence making a stub
function not exposed on UP builds when it needed to be.
Relocate the stub to the #else /* ! CONFIG_SMP */ section
and also annotate the relevant else/endif so that nobody
else falls into the same trap I did.
Reported-by: Michael Guntsche <mike@it-loops.com> Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This patch fixes port identification on optic devices when there's no link on the port.
Signed-off-by: Yaniv Rosner <yanivr@broadcom.com> Signed-off-by: Eilon Greenstein <eilong@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Merge branch 's5p-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung
* 's5p-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung:
ARM: SAMSUNG: Fix warning 's3c_pm_show_resume_irqs' defined but not used
ARM: SAMSUNG: Fix build failure in PM CRC check code
ARM: S5P: Remove unused s3c_pm_check_resume_pin
Following commit 091738a266fc ("genirq: Remove real old transition
functions") we removed an automatic conversion of no_irq_chip to
dummy_irq_chip. This change needs to be propagated back into the alpha
backend.
Signed-off-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is a new warning in gcc 4.6. Several of these variables are
used within #if 0 code, which probably ought to be removed. Most
of the changes are legitimate cleanups.
Signed-off-by: Richard Henderson <rth@twiddle.net> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Milton Miller [Thu, 14 Apr 2011 15:30:08 +0000 (10:30 -0500)]
fs: synchronize_rcu when unregister_filesystem success not failure
While checking unregister_filesystem for saftey vs extra calls for
"ext4: register ext2 and ext3 alias after ext4" I realized that
the synchronize_rcu() was called on the error path but not on
the success path.
Cc: stable (2.6.38) Signed-off-by: Milton Miller <miltonm@bga.com>
[ This probably won't really make a difference since commit d863b50ab013
("vfs: call rcu_barrier after ->kill_sb()"), but it's the right thing
to do. - Linus ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alex Deucher [Sun, 17 Apr 2011 08:20:19 +0000 (10:20 +0200)]
i2c-algo-bit: Call pre/post_xfer for bit_test
Apparently some distros set i2c-algo-bit.bit_test to 1 by
default. In some cases this causes i2c_bit_add_bus
to fail and prevents the i2c bus from being added. In the
radeon case, we fail to add the ddc i2c buses which prevents
the driver from being able to detect attached monitors.
The i2c bus works fine even if bit_test fails. This is likely
due to gpio switching that is required and handled in the
pre/post_xfer hooks, so call the pre/post_xfer hooks in the
bit test as well.
Jonathan Cameron [Thu, 14 Apr 2011 11:11:42 +0000 (12:11 +0100)]
ARM: 6881/1: cputype.h uses __attribute_const__ which requires including kernel.h
Issue manifests as:
In file included from arch/arm/mach-pxa/include/mach/hardware.h:62,
from arch/arm/mach-pxa/include/mach/gpio.h:28,
from /home/jic23/src/kernel/temp-remove/arch/arm/include/asm/gpio.h:5,
from include/linux/gpio.h:7,
from drivers/staging/iio/gyro/adis16080_core.c:8:
/home/jic23/src/kernel/temp-remove/arch/arm/include/asm/cputype.h:57: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'read_cpuid_id'
...
Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>