new helper: dir_relax(inode). Call when you are in location that will
_not_ be invalidated by directory modifications (block boundary, in case
of ext*). Returns whether the directory has survived (dropping i_mutex
allows rmdir to kill the sucker; if it returns false to us, ->iterate()
is obviously done)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
New method - ->iterate(file, ctx). That's the replacement for ->readdir();
it takes callback from ctx->actor, uses ctx->pos instead of file->f_pos and
calls dir_emit(ctx, ...) instead of filldir(data, ...). It does *not*
update file->f_pos (or look at it, for that matter); iterate_dir() does the
update.
Note that dir_emit() takes the offset from ctx->pos (and eventually
filldir_t will lose that argument).
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
iterate_dir(): new helper, replacing vfs_readdir().
struct dir_context: contains the readdir callback (and will get more stuff
in it), embedded into whatever data that callback wants to deal with;
eventually, we'll be passing it to ->readdir() replacement instead of
(data,filldir) pair.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Marc Kleine-Budde says:
====================
this is a pull-request for net-next/master. It consists of three
patches by Fabio Estevam and me, which convert the flexcan transceiver
switching to DT[1] and a patch by Sachin Kamat, which cleans up the
at91_can driver a bit.
[1] These patches touch arch/arm/mach-imx, so I collected Acked-bys
from Shawn Guo and Sascha Hauer.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Similar to linux/device.h, move of_node struct member out of the #ifdef
CONFIG_OF so that the drivers won't have to mess with #ifdefs in .c files.
Signed-off-by: Anton Vorontsov <anton@enomsg.org>
* labeled-nfs:
NFS: Apply v4.1 capabilities to v4.2
NFS: Add in v4.2 callback operation
NFS: Make callbacks minor version generic
Kconfig: Add Kconfig entry for Labeled NFS V4 client
NFS: Extend NFS xattr handlers to accept the security namespace
NFS: Client implementation of Labeled-NFS
NFS: Add label lifecycle management
NFS:Add labels to client function prototypes
NFSv4: Extend fattr bitmaps to support all 3 words
NFSv4: Introduce new label structure
NFSv4: Add label recommended attribute and NFSv4 flags
NFSv4.2: Added NFS v4.2 support to the NFS client
SELinux: Add new labeling type native labels
LSM: Add flags field to security_sb_set_mnt_opts for in kernel mount data.
Security: Add Hook to test if the particular xattr is part of a MAC model.
Security: Add hook to calculate context based on a negative dentry.
NFS: Add NFSv4.2 protocol constants
Conflicts:
fs/nfs/nfs4proc.c
Allow to change the AL layout with an resize operation. For that
the reisze command gets two new fields: al_stripes and al_stripe_size.
In order to make the operation crash save:
1) Lock out all IO and MD-IO
2) Write the super block with MDF_PRIMARY_IND clear
3) write the bitmap to the new location (all zeros, since
we allow only while connected)
4) Initialize the new AL-area
5) Write the super block with the restored MDF_PRIMARY_IND.
6) Unfreeze all IO
Since the AL-layout has no influence on the protocol, this operation
needs to be beforemed on both sides of a resource (if intended).
Signed-off-by: Andreas Gruenbacher <agruen@linbit.com>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
ASoC: More updates for v3.11
Some more fixes and enhancements, and also a bunch of refectoring for
AC'97 support which enables more than one AC'97 controller driver to be
built in.
* freezer:
af_unix: use freezable blocking calls in read
sigtimedwait: use freezable blocking call
nanosleep: use freezable blocking call
futex: use freezable blocking call
select: use freezable blocking call
epoll: use freezable blocking call
binder: use freezable blocking calls
freezer: add new freezable helpers using freezer_do_not_count()
freezer: convert freezable helpers to static inline where possible
freezer: convert freezable helpers to freezer_do_not_count()
freezer: skip waking up tasks with PF_FREEZER_SKIP set
freezer: shorten freezer sleep time using exponential backoff
lockdep: check that no locks held at freeze time
lockdep: remove task argument from debug_check_no_locks_held
freezer: add unsafe versions of freezable helpers for CIFS
freezer: add unsafe versions of freezable helpers for NFS
Since (c05cdb1 netlink: allow large data transfers from user-space),
netlink splats if it invokes skb_clone on large netlink skbs since:
* skb_shared_info was not correctly initialized.
* skb->destructor is not set in the cloned skb.
This was spotted by trinity:
[ 894.990671] BUG: unable to handle kernel paging request at ffffc9000047b001
[ 894.991034] IP: [<ffffffff81a212c4>] skb_clone+0x24/0xc0
[...]
[ 894.991034] Call Trace:
[ 894.991034] [<ffffffff81ad299a>] nl_fib_input+0x6a/0x240
[ 894.991034] [<ffffffff81c3b7e6>] ? _raw_read_unlock+0x26/0x40
[ 894.991034] [<ffffffff81a5f189>] netlink_unicast+0x169/0x1e0
[ 894.991034] [<ffffffff81a601e1>] netlink_sendmsg+0x251/0x3d0
Fix it by:
1) introducing a new netlink_skb_clone function that is used in nl_fib_input,
that sets our special skb->destructor in the cloned skb. Moreover, handle
the release of the large cloned skb head area in the destructor path.
2) not allowing large skbuffs in the netlink broadcast path. I cannot find
any reasonable use of the large data transfer using netlink in that path,
moreover this helps to skip extra skb_clone handling.
I found two more netlink clients that are cloning the skbs, but they are
not in the sendmsg path. Therefore, the sole client cloning that I found
seems to be the fib frontend.
Thanks to Eric Dumazet for helping to address this issue.
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The goal of this new function is to perform all needed cleanup before sending
an skb into another netns.
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
1672d04070 ("cgroup: fix cgroupfs_root early destruction path")
introduced CGRP_ROOT_SUBSYS_BOUND which is used to mark completion of
subsys binding on a new root; however, this broke remounts.
cgroup_remount() doesn't allow changing root options via remount and
CGRP_ROOT_SUBSYS_BOUND, which is set on all fully initialized roots,
makes the function reject all remounts.
Fix it by putting the options part in the lower 16 bits of root->flags
and masking the comparions. While at it, make cgroup_remount() emit
an error message explaining why it's rejecting a remount request, so
that it's less of a mystery.
Signed-off-by: Tejun Heo <tj@kernel.org>
This adds support for a generic reservations framework that can be
hooked up to ttm and dma-buf and allows easy sharing of reservations
across devices.
The idea is that a dma-buf and ttm object both will get a pointer
to a struct reservation_object, which has to be reserved before
anything is done with the contents of the dma-buf.
Changes since v1:
- Fix locking issue in ticket_reserve, which could cause mutex_unlock
to be called too many times.
Changes since v2:
- All fence related calls and members have been taken out for now,
what's left is the bare minimum to be useful for ttm locking conversion.
Changes since v3:
- Removed helper functions too. The documentation has an example
implementation for locking. With the move to ww_mutex there is no
need to have much logic any more.
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Commits fcf8058 (cpufreq: Simplify cpufreq_add_dev()) and aa77a52
(cpufreq: acpi-cpufreq: Don't set policy->related_cpus from .init())
changed the contents of the "related_cpus" sysfs attribute on systems
where acpi-cpufreq is used and user space can't get the list of CPUs
which are in the same hardware coordination CPU domain (provided by
the ACPI AML method _PSD) via "related_cpus" any more.
To make up for that loss add a new sysfs attribute "freqdomian_cpus"
for the acpi-cpufreq driver which exposes the list of CPUs in the
same domain regardless of whether it is coordinated by hardware or
software.
[rjw: Changelog, documentation]
References: https://bugzilla.kernel.org/show_bug.cgi?id=58761
Reported-by: Jean-Philippe Halimi <jean-philippe.halimi@exascale-computing.eu>
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Whenever we are changing frequency of a cpu, we are calling PRECHANGE and
POSTCHANGE notifiers. They must be serialized. i.e. PRECHANGE or POSTCHANGE
shouldn't be called twice contiguously.
This can happen due to bugs in users of __cpufreq_driver_target() or actual
cpufreq drivers who are sending these notifiers.
This patch adds some protection against this. Now, we keep track of the last
transaction and see if something went wrong.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
DMA engine of some old SDIO host controllers require block size alignment for
data length of each scatterlist item. This patch introduces an intermediate
buffer list to support this kind of platform. It decreases the throughput
because of an extra memcpy in critical data path. So don't turn this on unless
it's necessary.
Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com>
Reviewed-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: Franky Lin <frankyl@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
GMT G762/763 fan speed PWM controller is connected directly to a fan
and performs closed-loop or open-loop control of the fan speed. Two
modes - PWM or DC - are supported by the chip. Introduced driver
provides various knobs to control the operations of the chip (via
sysfs interface). Specific characteristics of the system can be passed
either using board init code or via DT. Documentation for both the
driver and DT bindings are also provided.
Signed-off-by: Arnaud Ebalard <arno@natisbad.org>
Tested-by: Simon Guinot <simon.guinot@sequanux.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Although the HC supports HS200 (eMMC) the caps2 are always zero; this
means there's no way to use the super speed mode (when init the card).
If the HC support SDR104, for SD3.0, so it also supports HS200 for eMMC
and this patch just sets the MMC_CAP2_HS200 in the host caps2 field.
Reported-by: Youssef Triki <youssef.triki@st.com>
Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Reviewed-by: Philip Rakity <prakity@nvidia.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
MMC_CAP2_FULL_PWR_CYCLE shall be set by host drivers which are able to
do a complete power cycle of the card. In the eMMC case that includes
both vcc and vccq.
This CAP is providing the protocol layer with important information,
needed to take optimized decisions during card initialization and in
the suspend/resume sequence.
MMC_CAP2_POWEROFF_NOTIFY is replaced by MMC_CAP2_FULL_PWR_CYCLE, since
it makes sense to use a wider scope for it.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
Considering shutdown of the card, the responsibility to initate this
sequence shall be driven from the mmc_bus.
This patch enables the mmc_bus to handle this sequence properly. A new
.shutdown callback is added in the mmc_driver struct which is used to
shutdown the blk device.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
In order to make it possible to reduce the SD bus frequency,
parse the optional "max-frequency" attribute as documented in
devicetree/bindings/mmc/mmc.txt
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
In addition to just logging errors encountered during DT parsing or
allocating GPIO slots for CD/WP, mmc_of_parse() now returns with an error.
In particular, this is needed if the GPIO allocation may return
EPROBE_DEFER.
Signed-off-by: Simon Baatz <gmbnomis@gmail.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
Renesas sh-sci updates for v3.11
HSCIF support by Ulrich Hecht.
* tag 'renesas-sh-sci-for-v3.11' of git://git.kernel.org/pub/scm/linux/kernel/git/horms/renesas:
serial: sh-sci: Initialise variables before access in sci_set_termios()
ARM: shmobile: r8a7790: don't use external clock for SCIFs
ARM: shmobile: r8a7790: HSCIF support
serial: sh-sci: HSCIF support
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Merge in the tip core/mutexes branch for future GPU driver use.
Ingo will send this branch to Linus prior to drm-next.
* 'core/mutexes' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
locking-selftests: Handle unexpected failures more strictly
mutex: Add more w/w tests to test EDEADLK path handling
mutex: Add more tests to lib/locking-selftest.c
mutex: Add w/w tests to lib/locking-selftest.c
mutex: Add w/w mutex slowpath debugging
mutex: Add support for wound/wait style locks
arch: Make __mutex_fastpath_lock_retval return whether fastpath succeeded or not
powerpc/pci: Fix boot panic on mpc83xx (regression)
s390/ipl: Fix FCP WWPN and LUN format strings for read
fs: fix new splice.c kernel-doc warning
spi/pxa2xx: fix memory corruption due to wrong size used in devm_kzalloc()
s390/mem_detect: fix memory hole handling
s390/dma: support debug_dma_mapping_error
s390/dma: fix mapping_error detection
s390/irq: Only define synchronize_irq() on SMP
Input: xpad - fix for "Mad Catz Street Fighter IV FightPad" controllers
Input: wacom - add a new stylus (0x100802) for Intuos5 and Cintiqs
spi/pxa2xx: use GFP_ATOMIC in sg table allocation
fuse: hold i_mutex in fuse_file_fallocate()
Input: add missing dependencies on CONFIG_HAS_IOMEM
...
Linux 3.10-rc7
The sdvo lvds fix in this -fixes pull
commit c3456fb3e4
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Mon Jun 10 09:47:58 2013 +0200
drm/i915: prefer VBT modes for SVDO-LVDS over EDID
has a silent functional conflict with
commit 990256aec2
Author: Ville Syrjälä <ville.syrjala@linux.intel.com>
Date: Fri May 31 12:17:07 2013 +0000
drm: Add probed modes in probe order
in drm-next. W simply need to add the vbt modes before edid modes, i.e. the
other way round than now.
Conflicts:
drivers/gpu/drm/drm_prime.c
drivers/gpu/drm/i915/intel_sdvo.c
drm_get_connector_name now returns a const value, which causes the following
compilation warning:
drivers/gpu/drm/drm_fb_helper.c: In function ‘drm_fb_helper_parse_command_line’:
drivers/gpu/drm/drm_fb_helper.c:127:3: warning: passing argument 1 of ‘fb_get_options’ discards ‘const’ qualifier from pointer target type [enabled by default]
In file included from drivers/gpu/drm/drm_fb_helper.c:35:0:
include/linux/fb.h:627:12: note: expected ‘char *’ but argument is of type ‘const char *’
As fb_get_options uses its name argument as read only, make it const. This
fixes the aforementioned compilation warning.
Signed-off-by: Vincent Stehlé <vincent.stehle@freescale.com>
Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Dave Airlie <airlied@redhat.com>
Cc: trivial@kernel.org
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Pull networking fixes from David Miller:
1) Found via trinity:
If you connect up an ipv6 socket to an ipv4 mapped address then an
ipv6 one, sendmsg() can croak because ip6_sk_dst_check() assumes the
route cached in the socket is an ipv6 one. In this case there is an
ipv4 route attached, so it gets stomped on.
Reported by Dave Jones and Hannes Frederic Sowa, fixed by Eric
Dumazet.
2) AF_KEY notifications leak some kernel memory to userspace, fix from
Mathias Krause.
3) DLCI calls __dev_get_by_name() without proper locking, and dlci_del
doesn't validate that the device being deleted is actually a DLCI
one. Fixes from Li Zefan.
4) Length check on bluetooth l2cap information responses is wrong, each
response type has a different lenth, so we should make sure it's in
a given range rather than enforce one single valid length. From
Jaganath Kanakkassery.
5) Receive FIFO overflow is really easy to trigger in stress scenerios
in the sh_eth driver, but the event isn't being handled properly at
all. Specifically, the mask of error interrupts doesn't include the
event so we never clear it, resulting in the driver becomming wedged
processing an interrupt that never gets cleared.
Fix from Sergei Shtylyov.
6) qlcnic sleeps while holding a spinlock, use mdelay() instead of
msleep(). From Shahed Shaikh.
7) Missing curly braces causes SIP netfilter NAT module to always drop
packets. Fix from Balazs Peter Odor.
8) ipt_ULOG in netfilter passes the wrong value to timer setup, causing
the timer to dereference crap when it fires. Fix from Gao Feng.
9) Missing RCU protection around txq->axq_acq traversal in
ath_txq_schedule(). Fix from Felix Fietkau.
10) Idle state transition test in ath9k_htc_config() is reversed, fix
from Sujith Manoharan.
11) IPV6 forwarding handles unicast Router Alert packets incorrectly.
It tests the wrong option state. Previously opt->ra being non-zero
indicated a router alert marking in the SKB, but now it's indicated
by a bit in opt->flags. Fix from YOSHIFUJI Hideaki.
12) SKB leak in GRE tunnel GSO handling, from Eric Dumazet.
13) get_user_pages_fast() error handling in TUN and MACVTAP use the same
local variable for the base index and the loop iterator for page
traversal, oops! Fix from Michael S Tsirkin.
14) ipv6_get_lladdr() can fail, and we must therefore check it's return
value in inet6_set_iftoken(). For from Hannes Frederic Sowa.
15) If you change an interface name and meanwhile can sneak in something
that looks up the name (like SO_BINDTODEVICE or SIOCGIFNAME) we can
deadlock with CONFIG_PREEMPT=n. Fix this by providing a helper
function that properly uses raw_seqcount_begin(). From Nicolas
Schichan.
16) Chain noise calibration test is inverted in iwlwifi, fix from
Nikolay Martynov.
17) Properly set TX iwlwifi descriptor flags for back requests. Fix
from Emmanuel Grumbach.
18) We can't assume skb_transport_header() is set in xt_TCPOPTSTRAP
module, fix from Pablo Neira Ayuso.
19) Some crummy APs don't provide the proper High Throughput info in
association response frames. Add a workaround by assume we'll use
whatever is in the beacon/probe. Fix from Johannes Berg.
20) mac80211 call to rate_idx_match_mask() swaps two arguments (mask and
channel width). Fix from Simon Wunderlich.
21) xt_TCPMSS (like xt_TCPOPTSTRAP) must not try to handle fragmented
frames. Fix from Phil Oester.
22) Fix rate control regression causing iwlwifi/iwlegacy chips to use
1Mbit/s on pre-11n networks. From Moshe Benji and Stanslaw Gruszka.
23) Disable brcmsmac power-save functions, they cause regressions. From
Arend van Spriel.
24) Enforce a sane minimum MTU in l2cap_build_cmd() otherwise we can
easily crash. Fix from Anderson Lizardo.
25) If a learning packet arrives during vxlan_stop() we crash, easily
fixed by checking netif_running(). From Stephen Hemminger.
26) Static vxlan FDB entries should not be migrated, also from Stephen.
27) skb_clone() failures not handled in vxlan_xmit(), oops. Also from
Stephen.
28) Add minimal driver for AR816x/AR817x ethernet chips, from Johannes
Berg.
29) Fix regression in userspace VLAN acceleration control, added by the
802.1ad support changes. Fix from Fernando Luis Vazquez Cao.
30) Interval selection for MLD queries in the bridging code was
reversed. Fix from Linus Lüssing.
31) ipv6's ndisc_send_redirect() erroneously writes to the packet we
received not the packet we are building to send out. Fix from
Matthias Schiffer.
32) Don't free netdev before unregistering it, in usb_8dev can driver.
From Marc Kleine-Budde.
33) Fix nl80211 attribute buffer races, from Johannes Berg.
34) Although netlink_diag.h is under uapi/ it isn't present in Kbuild.
From Stephen Hemminger.
35) Wrong address and family passed to MD5 key lookups in TCP, from
Aydin Arik.
36) phy_type attribute created by SFC driver should not be writable.
From Ben Hutchings.
37) Receive/Transmit queue allocations in pxa168_eth and mv643xx_eth
should use kzalloc(). Otherwise if setup fails half-way, we'll
dereference garbage when trying to teardown the rings. From Lubomir
Rintel.
38) Fix double-allocation of dst (resulting in unfreeable net device) in
ipv6's init_loopback(). From Gao Feng.
39) Fix fragmentation handling SKB leak in netfilter conntrack, we were
freeing the wrong skb pointer. From Phil Oester.
40) Don't report "-1" (SPEED_UNKNOWN) in bond_miimon_commit(), from
Nikolay Aleksandrov.
41) davinci_cpdma doesn't check for DMA mapping errors, letting the
device scribble to random addresses. From Sebastian Siewior.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (69 commits)
dlci: validate the net device in dlci_del()
dlci: acquire rtnl_lock before calling __dev_get_by_name()
af_key: fix info leaks in notify messages
ipv6: ip6_sk_dst_check() must not assume ipv6 dst
net: fix kernel deadlock with interface rename and netdev name retrieval.
net/tg3: Avoid delay during MMIO access
ipv6: check return value of ipv6_get_lladdr
macvtap: fix recovery from gup errors
tun: fix recovery from gup errors
gre: fix a possible skb leak
ipv6: Process unicast packet with Router Alert by checking flag in skb.
ath9k_htc: Handle IDLE state transition properly
ath9k: fix an RCU issue in calling ieee80211_get_tx_rates
netfilter: ipt_ULOG: fix incorrect setting of ulog timer
netfilter: ctnetlink: send event when conntrack label was modified
netfilter: nf_nat_sip: fix mangling
qlcnic: Do not sleep while holding spinlock
drivers: net: cpsw: fix compilation error with cpsw driver
tcp: doc : fix the syncookies default value
sh_eth: fix misreporting of transmit abort
...
The R-Car Display Unit (DU) DRM driver supports both superposition
processors and all eight planes in RGB and YUV formats with alpha
blending.
Only VGA and LVDS encoders and connectors are currently supported.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
* pci/misc:
MAINTAINERS: Add ACPI folks for ACPI-related things under drivers/pci
PCI: Add CircuitCo vendor ID and subsystem ID
PCI: Use pdev->pm_cap instead of pci_find_capability(..,PCI_CAP_ID_PM)
Add CircuitCo's newly created VENDOR ID and their first board subsystem
ID for the MinnowBoard.
[bhelgaas: sort, change DEVICE_ID to SUBSYSTEM_ID]
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
When the kernel (compiled with CONFIG_PREEMPT=n) is performing the
rename of a network interface, it can end up waiting for a workqueue
to complete. If userland is able to invoke a SIOCGIFNAME ioctl or a
SO_BINDTODEVICE getsockopt in between, the kernel will deadlock due to
the fact that read_secklock_begin() will spin forever waiting for the
writer process (the one doing the interface rename) to update the
devnet_rename_seq sequence.
This patch fixes the problem by adding a helper (netdev_get_name())
and using it in the code handling the SIOCGIFNAME ioctl and
SO_BINDTODEVICE setsockopt.
The netdev_get_name() helper uses raw_seqcount_begin() to avoid
spinning forever, waiting for devnet_rename_seq->sequence to become
even. cond_resched() is used in the contended case, before retrying
the access to give the writer process a chance to finish.
The use of raw_seqcount_begin() will incur some unneeded work in the
reader process in the contended case, but this is better than
deadlocking the system.
Signed-off-by: Nicolas Schichan <nschichan@freebox.fr>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Al Viro