KVM does not hold any references to rcu protected data when it switches
CPU into a guest mode. In fact switching to a guest mode is very similar
to exiting to userspase from rcu point of view. In addition CPU may stay
in a guest mode for quite a long time (up to one time slice). Lets treat
guest mode as quiescent state, just like we do with user-mode execution.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
* commit '29ce831000081dd757d3116bf774aafffc4b6b20': (34 commits)
rcu: provide rcu_virt_note_context_switch() function.
rcu: get rid of signed overflow in check_cpu_stall()
rcu: optimize rcutiny
rcu: prevent call_rcu() from diving into rcu core if irqs disabled
rcu: further lower priority in rcu_yield()
rcu: introduce kfree_rcu()
rcu: fix spelling
rcu: call __rcu_read_unlock() in exit_rcu for tree RCU
rcu: Converge TINY_RCU expedited and normal boosting
rcu: remove useless ->boosted_this_gp field
rcu: code cleanups in TINY_RCU priority boosting.
rcu: Switch to this_cpu() primitives
rcu: Use WARN_ON_ONCE for DEBUG_OBJECTS_RCU_HEAD warnings
rcu: mark rcutorture boosting callback as being on-stack
rcu: add DEBUG_OBJECTS_RCU_HEAD check for alignment
rcu: Enable DEBUG_OBJECTS_RCU_HEAD from !PREEMPT
rcu: Add forward-progress diagnostic for per-CPU kthreads
rcu: add grace-period age and more kthread state to tracing
rcu: fix tracing bug thinko on boost-balk attribution
rcu: update tracing documentation for new rcutorture and rcuboost
...
Pulling in rcu_virt_note_context_switch().
Signed-off-by: Avi Kivity <avi@redhat.com>
* commit '29ce831000081dd757d3116bf774aafffc4b6b20': (34 commits)
rcu: provide rcu_virt_note_context_switch() function.
rcu: get rid of signed overflow in check_cpu_stall()
rcu: optimize rcutiny
rcu: prevent call_rcu() from diving into rcu core if irqs disabled
rcu: further lower priority in rcu_yield()
rcu: introduce kfree_rcu()
rcu: fix spelling
rcu: call __rcu_read_unlock() in exit_rcu for tree RCU
rcu: Converge TINY_RCU expedited and normal boosting
rcu: remove useless ->boosted_this_gp field
rcu: code cleanups in TINY_RCU priority boosting.
rcu: Switch to this_cpu() primitives
rcu: Use WARN_ON_ONCE for DEBUG_OBJECTS_RCU_HEAD warnings
rcu: mark rcutorture boosting callback as being on-stack
rcu: add DEBUG_OBJECTS_RCU_HEAD check for alignment
rcu: Enable DEBUG_OBJECTS_RCU_HEAD from !PREEMPT
rcu: Add forward-progress diagnostic for per-CPU kthreads
rcu: add grace-period age and more kthread state to tracing
rcu: fix tracing bug thinko on boost-balk attribution
rcu: update tracing documentation for new rcutorture and rcuboost
...
This patch avoids gcc issuing the following warning when KVM_MAX_VCPUS=1:
warning: array subscript is above array bounds
kvm_for_each_vcpu currently checks to see if the index for the vcpu is
valid /after/ loading it. We don't run into problems because the address
is still inside the enclosing struct kvm and we never deference or write
to it, so this isn't a security issue.
The warning occurs when KVM_MAX_VCPUS=1 because the increment portion of
the loop will *always* cause the loop to load an invalid location since
++idx will always be > 0.
This patch moves the load so that the check occurs before the load and
we don't run into the compiler warning.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
This patch implements two new vm-ioctls to get and set the
virtual_tsc_khz if the machine supports tsc-scaling. Setting
the tsc-frequency is only possible before userspace creates
any vcpu.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Since sse instructions can issue 16-byte mmios, we need to support them. We
can't increase the kvm_run mmio buffer size to 16 bytes without breaking
compatibility, so instead we break the large mmios into two smaller 8-byte
ones. Since the bus is 64-bit we aren't breaking any atomicity guarantees.
Signed-off-by: Avi Kivity <avi@redhat.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (27 commits)
slcan: fix ldisc->open retval
net/usb: mark LG VL600 LTE modem ethernet interface as WWAN
xfrm: Don't allow esn with disabled anti replay detection
xfrm: Assign the inner mode output function to the dst entry
net: dev_close() should check IFF_UP
vlan: fix GVRP at dismantle time
netfilter: revert a2361c8735
netfilter: IPv6: fix DSCP mangle code
netfilter: IPv6: initialize TOS field in REJECT target module
IPVS: init and cleanup restructuring
IPVS: Change of socket usage to enable name space exit.
netfilter: ebtables: only call xt_compat_add_offset once per rule
netfilter: fix ebtables compat support
netfilter: ctnetlink: fix timestamp support for new conntracks
pch_gbe: support ML7223 IOH
PCH_GbE : Fixed the issue of checksum judgment
PCH_GbE : Fixed the issue of collision detection
NET: slip, fix ldisc->open retval
be2net: Fixed bugs related to PVID.
ehea: fix wrongly reported speed and port
...
As it is, we assign the outer modes output function to the dst entry
when we create the xfrm bundle. This leads to two problems on interfamily
scenarios. We might insert ipv4 packets into ip6_fragment when called
from xfrm6_output. The system crashes if we try to fragment an ipv4
packet with ip6_fragment. This issue was introduced with git commit
ad0081e4 (ipv6: Fragment locally generated tunnel-mode IPSec6 packets
as needed). The second issue is, that we might insert ipv4 packets in
netfilter6 and vice versa on interfamily scenarios.
With this patch we assign the inner mode output function to the dst entry
when we create the xfrm bundle. So xfrm4_output/xfrm6_output from the inner
mode is used and the right fragmentation and netfilter functions are called.
We switch then to outer mode with the output_finish functions.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
DESCRIPTION
This patch tries to restore the initial init and cleanup
sequences that was before namspace patch.
Netns also requires action when net devices unregister
which has never been implemented. I.e this patch also
covers when a device moves into a network namespace,
and has to be released.
IMPLEMENTATION
The number of calls to register_pernet_device have been
reduced to one for the ip_vs.ko
Schedulers still have their own calls.
This patch adds a function __ip_vs_service_cleanup()
and an enable flag for the netfilter hooks.
The nf hooks will be enabled when the first service is loaded
and never disabled again, except when a namespace exit starts.
Signed-off-by: Hans Schillstrom <hans@schillstrom.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
[horms@verge.net.au: minor edit to changelog]
Signed-off-by: Simon Horman <horms@verge.net.au>
Linux kernel excludes guard page when performing mlock on a VMA with
down-growing stack. However, some architectures have up-growing stack
and locking the guard page should be excluded in this case too.
This patch fixes lvm2 on PA-RISC (and possibly other architectures with
up-growing stack). lvm2 calculates number of used pages when locking and
when unlocking and reports an internal error if the numbers mismatch.
[ Patch changed fairly extensively to also fix /proc/<pid>/maps for the
grows-up case, and to move things around a bit to clean it all up and
share the infrstructure with the /proc bits.
Tested on ia64 that has both grow-up and grow-down segments - Linus ]
Signed-off-by: Mikulas Patocka <mikulas@artax.karlin.mff.cuni.cz>
Tested-by: Tony Luck <tony.luck@gmail.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6:
drm/radeon/kms: add pci id to acer travelmate quirk for 5730
drm/radeon: fix order of doing things in radeon_crtc_cursor_set
drm: mm: fix debug output
drm/radeon/kms: ATPX switcheroo fixes
drm/nouveau: Fix a crash at card takedown for NV40 and older cards
The looping helper didn't do anything due to a superficial
semicolon. Furthermore one of the two dump functions suffered
from copy&paste fail.
While staring at the code I've also noticed that the replace
helper (currently unused) is a bit broken.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This partially reverts commit e6e1e25935.
That commit changed the structure layout of the trace structure, which
in turn broke PowerTOP (1.9x generation) quite badly.
I appreciate not wanting to expose the variable in question, and
PowerTOP was not using it, so I've replaced the variable with just a
padding field - that way if in the future a new field is needed it can
just use this padding field.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Provide rcu_virt_note_context_switch() for vitalization use to note
quiescent state during guest entry.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Many rcu callbacks functions just call kfree() on the base structure.
These functions are trivial, but their size adds up, and furthermore
when they are used in a kernel module, that module must invoke the
high-latency rcu_barrier() function at module-unload time.
The kfree_rcu() function introduced by this commit addresses this issue.
Rather than encoding a function address in the embedded rcu_head
structure, kfree_rcu() instead encodes the offset of the rcu_head
structure within the base structure. Because the functions are not
allowed in the low-order 4096 bytes of kernel virtual memory, offsets
up to 4095 bytes can be accommodated. If the offset is larger than
4095 bytes, a compile-time error will be generated in __kfree_rcu().
If this error is triggered, you can either fall back to use of call_rcu()
or rearrange the structure to position the rcu_head structure into the
first 4096 bytes.
Note that the allowable offset might decrease in the future, for example,
to allow something like kmem_cache_free_rcu().
The new kfree_rcu() function can replace code as follows:
call_rcu(&p->rcu, simple_kfree_callback);
where "simple_kfree_callback()" might be defined as follows:
void simple_kfree_callback(struct rcu_head *p)
{
struct foo *q = container_of(p, struct foo, rcu);
kfree(q);
}
with the following:
kfree_rcu(&p->rcu, rcu);
Note that the "rcu" is the name of a field in the structure being
freed. The reason for using this rather than passing in a pointer
to the base structure is that the above approach allows better type
checking.
This commit is based on earlier work by Lai Jiangshan and Manfred Spraul:
Lai's V1 patch: http://lkml.org/lkml/2008/9/18/1
Manfred's patch: http://lkml.org/lkml/2009/1/2/115
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: David Howells <dhowells@redhat.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Verify that rcu_head structures are aligned to a four-byte boundary.
This check is enabled by CONFIG_DEBUG_OBJECTS_RCU_HEAD.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
It is not possible to accurately correlate rcutorture output with that
of debugfs. This patch therefore adds a debugfs file that prints out
the rcutorture version number, permitting easy correlation.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
If RCU priority boosting is to be meaningful, callback invocation must
be boosted in addition to preempted RCU readers. Otherwise, in presence
of CPU real-time threads, the grace period ends, but the callbacks don't
get invoked. If the callbacks don't get invoked, the associated memory
doesn't get freed, so the system is still subject to OOM.
But it is not reasonable to priority-boost RCU_SOFTIRQ, so this commit
moves the callback invocations to a kthread, which can be boosted easily.
Also add comments and properly synchronized all accesses to
rcu_cpu_kthread_task, as suggested by Lai Jiangshan.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6:
flex_arrays: allow zero length flex arrays
flex_array: flex_array_prealloc takes a number of elements, not an end
SELinux: pass last path component in may_create
The SLUB allocator use of the cmpxchg_double logic was wrong: it
actually needs the irq-safe one.
That happens automatically when we use the native unlocked 'cmpxchg8b'
instruction, but when compiling the kernel for older x86 CPUs that do
not support that instruction, we fall back to the generic emulation
code.
And if you don't specify that you want the irq-safe version, the generic
code ends up just open-coding the cmpxchg8b equivalent without any
protection against interrupts or preemption. Which definitely doesn't
work for SLUB.
This was reported by Werner Landgraf <w.landgraf@ru.ru>, who saw
instability with his distro-kernel that was compiled to support pretty
much everything under the sun. Most big Linux distributions tend to
compile for PPro and later, and would never have noticed this problem.
This also fixes the prototypes for the irqsafe cmpxchg_double functions
to use 'bool' like they should.
[ Btw, that whole "generic code defaults to no protection" design just
sounds stupid - if the code needs no protection, there is no reason to
use "cmpxchg_double" to begin with. So we should probably just remove
the unprotected version entirely as pointless. - Linus ]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reported-and-tested-by: werner <w.landgraf@ru.ru>
Acked-and-tested-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1105041539050.3005@ionos
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Out of the entire GART/VM subsystem, the hw designers changed
the location of 3 regs.
v2: airlied: add parameter for userspace to work from.
Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: wm831x-ts - move BTN_TOUCH reporting to data transfer
Input: wm831x-ts - allow IRQ flags to be specified
Input: wm831x-ts - fix races with IRQ management
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (47 commits)
sysctl: net: call unregister_net_sysctl_table where needed
Revert: veth: remove unneeded ifname code from veth_newlink()
smsc95xx: fix reset check
tg3: Fix failure to enable WoL by default when possible
networking: inappropriate ioctl operation should return ENOTTY
amd8111e: trivial typo spelling: Negotitate -> Negotiate
ipv4: don't spam dmesg with "Using LC-trie" messages
af_unix: Only allow recv on connected seqpacket sockets.
mii: add support of pause frames in mii_get_an
net: ftmac100: fix scheduling while atomic during PHY link status change
usbnet: Transfer of maintainership
usbnet: add support for some Huawei modems with cdc-ether ports
bnx2: cancel timer on device removal
iwl4965: fix "Received BA when not expected"
iwlagn: fix "Received BA when not expected"
dsa/mv88e6131: fix unknown multicast/broadcast forwarding on mv88e6085
usbnet: Resubmit interrupt URB if device is open
iwl4965: fix "TX Power requested while scanning"
iwlegacy: led stay solid on when no traffic
b43: trivial: update module info about ucode16_mimo firmware
...
Move the SMBus device ID definitions of recent devices from pci_ids.h
to the i2c-i801.c driver file. They don't have to be shared, as they
are clearly identified and only used in this driver. In the future,
such IDs will go to i2c-i801 directly. This will make adding support
for new devices much faster and easier, as it will avoid cross-
subsystem patch sets and merge conflicts.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Seth Heasley <seth.heasley@intel.com>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
* 'drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6:
drm/i915: restore only the mode of this driver on lastclose (v2)
drm/radeon/kms: add info query for tile pipes
drm/radeon/kms: add missing safe regs for 6xx/7xx
drm: select FRAMEBUFFER_CONSOLE_PRIMARY if we have FRAMEBUFFER_CONSOLE
* 'bugfixes' of git://git.linux-nfs.org/projects/trondmy/nfs-2.6:
nfs: don't lose MS_SYNCHRONOUS on remount of noac mount
NFS: Return meaningful status from decode_secinfo()
NFSv4: Ensure we request the ordinary fileid when doing readdirplus
NFSv4: Ensure that clientid and session establishment can time out
SUNRPC: Allow RPC calls to return ETIMEDOUT instead of EIO
NFSv4.1: Don't loop forever in nfs4_proc_create_session
NFSv4: Handle NFS4ERR_WRONGSEC outside of nfs4_handle_exception()
NFSv4.1: Don't update sequence number if rpc_task is not sent
NFSv4.1: Ensure state manager thread dies on last umount
SUNRPC: Fix the SUNRPC Kerberos V RPCSEC_GSS module dependencies
NFS: Use correct variable for page bounds checking
NFS: don't negotiate when user specifies sec flavor
NFS: Attempt mount with default sec flavor first
NFS: flav_array honors NFS_MAX_SECFLAVORS
NFS: Fix infinite loop in gss_create_upcall()
Don't mark_inode_dirty_sync() while holding lock
NFS: Get rid of pointless test in nfs_commit_done
NFS: Remove unused argument from nfs_find_best_sec()
NFS: Eliminate duplicate call to nfs_mark_request_dirty
NFS: Remove dead code from nfs_fs_mount()
Change flex_array_prealloc to take the number of elements for which space
should be allocated instead of the last (inclusive) element. Users
and documentation are updated accordingly. flex_arrays got introduced before
they had users. When folks started using it, they ended up needing a
different API than was coded up originally. This swaps over to the API that
folks apparently need.
Based-on-patch-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
Tested-by: Chris Richards <gizmo@giz-works.com>
Acked-by: Dave Hansen <dave@linux.vnet.ibm.com>
Cc: stable@kernel.org [2.6.38+]
Resubmit interrupt URB if device is open. Use a flag set in
usbnet_open() to determine this state. Also kill and free
interrupt URB in usbnet_disconnect().
[Rebased off git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git]
Signed-off-by: Paul Stewart <pstew@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The huge_memory.c THP page fault was allowed to run if vm_ops was null
(which would succeed for /dev/zero MAP_PRIVATE, as the f_op->mmap wouldn't
setup a special vma->vm_ops and it would fallback to regular anonymous
memory) but other THP logics weren't fully activated for vmas with vm_file
not NULL (/dev/zero has a not NULL vma->vm_file).
So this removes the vm_file checks so that /dev/zero also can safely use
THP (the other albeit safer approach to fix this bug would have been to
prevent the THP initial page fault to run if vm_file was set).
After removing the vm_file checks, this also makes huge_memory.c stricter
in khugepaged for the DEBUG_VM=y case. It doesn't replace the vm_file
check with a is_pfn_mapping check (but it keeps checking for VM_PFNMAP
under VM_BUG_ON) because for a is_cow_mapping() mapping VM_PFNMAP should
only be allowed to exist before the first page fault, and in turn when
vma->anon_vma is null (so preventing khugepaged registration). So I tend
to think the previous comment saying if vm_file was set, VM_PFNMAP might
have been set and we could still be registered in khugepaged (despite
anon_vma was not NULL to be registered in khugepaged) was too paranoid.
The is_linear_pfn_mapping check is also I think superfluous (as described
by comment) but under DEBUG_VM it is safe to stay.
Addresses https://bugzilla.kernel.org/show_bug.cgi?id=33682
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reported-by: Caspar Zhang <bugs@casparzhang.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: <stable@kernel.org> [2.6.38.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This allows maximum flexibility for configuring the direct GPIO based
interrupts.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Currently there is a race in the MMC core between a card-detect
rescan work and the clock-gating work, scheduled from a command
completion. Fix it by removing the dedicated clock-gating mutex
and using the MMC standard locking mechanism instead.
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Cc: Simon Horman <horms@verge.net.au>
Cc: Magnus Damm <damm@opensource.se>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: <stable@kernel.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
* 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6: (42 commits)
[media] media: vb2: correct queue initialization order
[media] media: vb2: fix incorrect v4l2_buffer->flags handling
[media] s5p-fimc: Add support for the buffer timestamps and sequence
[media] s5p-fimc: Fix bytesperline and plane payload setup
[media] s5p-fimc: Do not allow changing format after REQBUFS
[media] s5p-fimc: Fix FIMC3 pixel limits on Exynos4
[media] tda18271: update tda18271c2_rf_cal as per NXP's rev.04 datasheet
[media] tda18271: update tda18271_rf_band as per NXP's rev.04 datasheet
[media] tda18271: fix bad calculation of main post divider byte
[media] tda18271: prog_cal and prog_tab variables should be s32, not u8
[media] tda18271: fix calculation bug in tda18271_rf_tracking_filters_init
[media] omap3isp: queue: Don't corrupt buf->npages when get_user_pages() fails
[media] v4l: Don't register media entities for subdev device nodes
[media] omap3isp: Don't increment node entity use count when poweron fails
[media] omap3isp: lane shifter support
[media] omap3isp: ccdc: support Y10/12, 8-bit bayer fmts
[media] media: add missing 8-bit bayer formats and Y12
[media] v4l: add V4L2_PIX_FMT_Y12 format
cx23885: Fix stv0367 Kconfig dependency
[media] omap3isp: Use isp xclk defines
...
Fix up trivial conflict (spelink errurs) in drivers/media/video/omap3isp/isp.c
When readdir() returns a directory entry for the root of a mounted
filesystem, Linux follows the old convention of returning the inode
number of the covered directory (despite newer versions of POSIX declaring
that this is a bug).
To ensure this continues to work, the NFSv4 readdir implementation requests
the 'mounted-on-fileid' from the server.
However, readdirplus also needs to instantiate an inode for this entry, and
for that, we also need to request the real fileid as per this patch.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
i915 calls the panic handler function on last close to reset the modes,
however this is a really bad idea for multi-gpu machines, esp shareable
gpus machines. So add a new entry point for the driver to just restore
its own fbcon mode.
v2: move code into fb helper, fix panic code to block mode change on
powered off GPUs.
[airlied: this hits drm core and I wrote it and it was reviewed on intel-gfx
so really I signed it off twice ;-).]
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Now that the whole dcache_hash_bucket crap is gone, go all the way and
also remove the weird locking layering violations for locking the hash
buckets. Add hlist_bl_lock/unlock helpers to move the locking into the
list abstraction instead of requiring each caller to open code it.
After all allowing for the bit locks is the whole point of these helpers
over the plain hlist variant.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When we are waiting for the bit-lock to be released, and are looping
over the 'cpu_relax()' should not be doing anything else - otherwise we
miss the point of trying to do the whole 'cpu_relax()'.
Do the preemption enable/disable around the loop, rather than inside of
it.
Noticed when I was looking at the code generation for the dcache
__d_drop usage, and the code just looked very odd.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When a task is traced and is in a stopped state, the tracer
may execute a ptrace request to examine the tracee state and
get its task struct. Right after, the tracee can be killed
and thus its breakpoints released.
This can happen concurrently when the tracer is in the middle
of reading or modifying these breakpoints, leading to dereferencing
a freed pointer.
Hence, to prepare the fix, create a generic breakpoint reference
holding API. When a reference on the breakpoints of a task is
held, the breakpoints won't be released until the last reference
is dropped. After that, no more ptrace request on the task's
breakpoints can be serviced for the tracer.
Reported-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Prasad <prasad@linux.vnet.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: v2.6.33.. <stable@kernel.org>
Link: http://lkml.kernel.org/r/1302284067-7860-2-git-send-email-fweisbec@gmail.com
On occasion, it is useful for the NFS layer to distinguish between
soft timeouts and other EIO errors due to (say) encoding errors,
or authentication errors.
The following patch ensures that the default behaviour of the RPC
layer remains to return EIO on soft timeouts (until we have
audited all the callers).
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
If a server for some reason keeps sending NFS4ERR_DELAY errors, we can end
up looping forever inside nfs4_proc_create_session, and so the usual
mechanisms for detecting if the nfs_client is dead don't work.
Fix this by ensuring that we loop inside the nfs4_state_manager thread
instead.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
