linux-pinenote/net
Dan Streetman b51d23e4e9 module: add per-module param_lock
Add a "param_lock" mutex to each module, and update params.c to use
the correct built-in or module mutex while locking kernel params.
Remove the kparam_block_sysfs_r/w() macros, replace them with direct
calls to kernel_param_[un]lock(module).

The kernel param code currently uses a single mutex to protect
modification of any and all kernel params.  While this generally works,
there is one specific problem with it; a module callback function
cannot safely load another module, i.e. with request_module() or even
with indirect calls such as crypto_has_alg().  If the module to be
loaded has any of its params configured (e.g. with a /etc/modprobe.d/*
config file), then the attempt will result in a deadlock between the
first module param callback waiting for modprobe, and modprobe trying to
lock the single kernel param mutex to set the new module's param.

This fixes that by using per-module mutexes, so that each individual module
is protected against concurrent changes in its own kernel params, but is
not blocked by changes to other module params.  All built-in modules
continue to use the built-in mutex, since they will always be loaded at
runtime and references (e.g. request_module(), crypto_has_alg()) to them
will never cause load-time param changing.

This also simplifies the interface used by modules to block sysfs access
to their params; while there are currently functions to block and unblock
sysfs param access which are split up by read and write and expect a single
kernel param to be passed, their actual operation is identical and applies
to all params, not just the one passed to them; they simply lock and unlock
the global param mutex.  They are replaced with direct calls to
kernel_param_[un]lock(THIS_MODULE), which locks THIS_MODULE's param_lock, or
if the module is built-in, it locks the built-in mutex.

Suggested-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Dan Streetman <ddstreet@ieee.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-06-23 15:27:38 +09:30
..
6lowpan
9p 9p: patches for 4.1 merge window 2015-04-18 17:45:30 -04:00
802 net: Kill dev_rebuild_header 2015-03-02 16:43:41 -05:00
8021q vlan: Correctly propagate promisc|allmulti flags in notifier. 2015-05-14 00:54:32 -04:00
appletalk appletalk: Use eth_<foo>_addr instead of memset 2015-03-03 17:01:37 -05:00
atm Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2015-04-15 09:00:47 -07:00
ax25 ax25: Fix the build when CONFIG_INET is disabled 2015-03-05 13:17:39 -05:00
batman-adv dev: introduce dev_get_iflink() 2015-04-02 14:04:59 -04:00
bluetooth Bluetooth: Fix remote name event return directly. 2015-05-14 10:35:04 +02:00
bridge bridge: fix lockdep splat 2015-05-22 16:23:56 -04:00
caif Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-03-20 18:51:09 -04:00
can can: introduce new raw socket option to join the given CAN filters 2015-04-01 11:28:22 +02:00
ceph Revert "libceph: clear r_req_lru_item in __unregister_linger_request()" 2015-05-20 21:02:46 +03:00
core net: core: 'ethtool' issue with querying phy settings 2015-05-22 16:14:17 -04:00
dcb net/dcb: Add IEEE QCN attribute 2015-03-06 21:50:02 -05:00
dccp inet: fix possible panic in reqsk_queue_unlink() 2015-04-24 11:39:15 -04:00
decnet netfilter: Pass socket pointer down through okfn(). 2015-04-07 15:25:55 -04:00
dns_resolver
dsa net: dsa: Fix scope of eeprom-length property 2015-04-29 15:35:04 -04:00
ethernet ethernet: Use eth_<foo>_addr instead of memset 2015-03-03 17:01:38 -05:00
hsr net/hsr: Fix NULL pointer dereference and refcnt bugs when deleting a HSR interface. 2015-03-01 13:40:23 -05:00
ieee802154 ieee802154: trace: fix endian convertion 2015-04-30 18:48:11 +02:00
ipv4 ipv4: fill in table id when replacing a route 2015-05-22 14:33:17 -04:00
ipv6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf 2015-05-22 14:25:45 -04:00
ipx net: Remove iocb argument from sendmsg and recvmsg 2015-03-02 13:06:31 -05:00
irda Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-03-09 23:38:02 -04:00
iucv Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-04-02 16:16:53 -04:00
key xfrm: simplify xfrm_address_t use 2015-03-31 13:58:35 -04:00
l2tp Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-04-06 22:34:15 -04:00
lapb
llc net: Remove iocb argument from sendmsg and recvmsg 2015-03-02 13:06:31 -05:00
mac80211 module: add per-module param_lock 2015-06-23 15:27:38 +09:30
mac802154 Merge branch 'for-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth 2015-05-09 15:51:00 -04:00
mpls mpls: Change reserved label names to be consistent with netbsd 2015-05-09 22:29:50 -04:00
netfilter netfilter: nfnetlink_{log,queue}: Register pernet in first place 2015-05-20 13:46:48 +02:00
netlabel netlink: implement nla_put_in_addr and nla_put_in6_addr 2015-03-31 13:58:35 -04:00
netlink netlink: Reset portid after netlink_insert failure 2015-05-16 17:08:57 -04:00
netrom net: Kill dev_rebuild_header 2015-03-02 16:43:41 -05:00
nfc nfc: Fix portid type in urelease_work 2015-04-13 16:35:16 -04:00
openvswitch Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2015-04-15 09:00:47 -07:00
packet af_packet / TX_RING not fully non-blocking (w/ MSG_DONTWAIT). 2015-05-10 19:40:08 -04:00
phonet net: Remove iocb argument from sendmsg and recvmsg 2015-03-02 13:06:31 -05:00
rds net/rds: RDS-TCP: only initiate reconnect attempt on outgoing TCP socket. 2015-05-09 16:03:28 -04:00
rfkill
rose net: Kill dev_rebuild_header 2015-03-02 16:43:41 -05:00
rxrpc new helper: msg_data_left() 2015-04-11 15:53:35 -04:00
sched net: sched: fix call_rcu() race on classifier module unloads 2015-05-21 18:48:18 -04:00
sctp sctp: avoid to repeatedly declare external variables 2015-03-25 11:40:16 -04:00
sunrpc kernel/params: constify struct kernel_param_ops uses 2015-05-28 11:32:10 +09:30
switchdev rename RTNH_F_EXTERNAL to RTNH_F_OFFLOAD 2015-05-14 22:45:39 -04:00
tipc tipc: fix problem with parallel link synchronization mechanism 2015-04-29 15:08:59 -04:00
unix Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-04-27 14:05:19 -07:00
vmw_vsock net: Remove iocb argument from sendmsg and recvmsg 2015-03-02 13:06:31 -05:00
wimax
wireless cfg80211: don't allow disabling WEXT if it's required 2015-04-08 09:19:29 +02:00
x25 net: Remove iocb argument from sendmsg and recvmsg 2015-03-02 13:06:31 -05:00
xfrm Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-04-14 15:44:14 -04:00
compat.c net: switch importing msghdr from userland to {compat_,}import_iovec() 2015-04-09 00:02:26 -04:00
Kconfig
Makefile mpls: Refactor how the mpls module is built 2015-03-04 00:26:06 -05:00
socket.c VFS: net/: d_inode() annotations 2015-04-15 15:06:56 -04:00
sysctl_net.c