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2007-11-01[NET]: Forget the zero_it argument of sk_alloc()Pavel Emelyanov1-1/+1
Finally, the zero_it argument can be completely removed from the callers and from the function prototype. Besides, fix the checkpatch.pl warnings about using the assignments inside if-s. This patch is rather big, and it is a part of the previous one. I splitted it wishing to make the patches more readable. Hope this particular split helped. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-26[NET]: Marking struct pernet_operations __net_initdata was inappropriateEric W. Biederman1-1/+1
It is not safe to to place struct pernet_operations in a special section. We need struct pernet_operations to last until we call unregister_pernet_subsys. Which doesn't happen until module unload. So marking struct pernet_operations is a disaster for modules in two ways. - We discard it before we call the exit method it points to. - Because I keep struct pernet_operations on a linked list discarding it for compiled in code removes elements in the middle of a linked list and does horrible things for linked insert. So this looks safe assuming __exit_refok is not discarded for modules. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-23[NETLINK]: Fix ACK processing after netlink_dump_startDenis V. Lunev1-4/+12
Revert to original netlink behavior. Do not reply with ACK if the netlink dump has bees successfully started. libnl has been broken by the cd40b7d3983c708aabe3d3008ec64ffce56d33b0 The following command reproduce the problem: /nl-route-get 192.168.1.1 Signed-off-by: Denis V. Lunev <den@openvz.org> Acked-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-15[NETLINK]: Don't leak 'listeners' in netlink_kernel_create()Jesper Juhl1-0/+2
The Coverity checker spotted that we'll leak the storage allocated to 'listeners' in netlink_kernel_create() when the if (!nl_table[unit].registered) check is false. This patch avoids the leak. Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[NET]: make netlink user -> kernel interface synchroniousDenis V. Lunev2-113/+51
This patch make processing netlink user -> kernel messages synchronious. This change was inspired by the talk with Alexey Kuznetsov about current netlink messages processing. He says that he was badly wrong when introduced asynchronious user -> kernel communication. The call netlink_unicast is the only path to send message to the kernel netlink socket. But, unfortunately, it is also used to send data to the user. Before this change the user message has been attached to the socket queue and sk->sk_data_ready was called. The process has been blocked until all pending messages were processed. The bad thing is that this processing may occur in the arbitrary process context. This patch changes nlk->data_ready callback to get 1 skb and force packet processing right in the netlink_unicast. Kernel -> user path in netlink_unicast remains untouched. EINTR processing for in netlink_run_queue was changed. It forces rtnl_lock drop, but the process remains in the cycle until the message will be fully processed. So, there is no need to use this kludges now. Signed-off-by: Denis V. Lunev <den@openvz.org> Acked-by: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[NET]: unify netlink kernel socket recognitionDenis V. Lunev1-4/+9
There are currently two ways to determine whether the netlink socket is a kernel one or a user one. This patch creates a single inline call for this purpose and unifies all the calls in the af_netlink.c No similar calls are found outside af_netlink.c. Signed-off-by: Denis V. Lunev <den@openvz.org> Acked-by: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[NET]: cleanup 3rd argument in netlink_sendskbDenis V. Lunev1-2/+2
netlink_sendskb does not use third argument. Clean it and save a couple of bytes. Signed-off-by: Denis V. Lunev <den@openvz.org> Acked-by: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[NET]: Make netlink processing routines semi-synchronious (inspired by rtnl) v2Denis V. Lunev1-12/+3
The code in netfilter/nfnetlink.c and in ./net/netlink/genetlink.c looks like outdated copy/paste from rtnetlink.c. Push them into sync with the original. Changes from v1: - deleted comment in nfnetlink_rcv_msg by request of Patrick McHardy Signed-off-by: Denis V. Lunev <den@openvz.org> Acked-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[NET]: Make core networking code use seq_open_privatePavel Emelyanov1-11/+2
This concerns the ipv4 and ipv6 code mostly, but also the netlink and unix sockets. The netlink code is an example of how to use the __seq_open_private() call - it saves the net namespace on this private. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[NETNS]: Move some code into __init section when CONFIG_NET_NS=nPavel Emelyanov1-3/+3
With the net namespaces many code leaved the __init section, thus making the kernel occupy more memory than it did before. Since we have a config option that prohibits the namespace creation, the functions that initialize/finalize some netns stuff are simply not needed and can be freed after the boot. Currently, this is almost not noticeable, since few calls are no longer in __init, but when the namespaces will be merged it will be possible to free more code. I propose to use the __net_init, __net_exit and __net_initdata "attributes" for functions/variables that are not used if the CONFIG_NET_NS is not set to save more space in memory. The exiting functions cannot just reside in the __exit section, as noticed by David, since the init section will have references on it and the compilation will fail due to modpost checks. These references can exist, since the init namespace never dies and the exit callbacks are never called. So I introduce the __exit_refok attribute just like it is already done with the __init_refok. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[NETLINK]: the temp variable name max is ambiguousDenis Cheng1-6/+6
with the macro max provided by <linux/kernel.h>, so changed its name to a more proper one: limit Signed-off-by: Denis Cheng <crquan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[NETLINK]: use the macro min(x,y) provided by <linux/kernel.h> insteadDenis Cheng1-1/+1
Signed-off-by: Denis Cheng <crquan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[NETLINK]: Avoid pointer in netlink_run_queueHerbert Xu2-9/+11
I was looking at Patrick's fix to inet_diag and it occured to me that we're using a pointer argument to return values unnecessarily in netlink_run_queue. Changing it to return the value will allow the compiler to generate better code since the value won't have to be memory-backed. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[NET]: Fix race when opening a proc file while a network namespace is exiting.Eric W. Biederman1-1/+5
The problem: proc_net files remember which network namespace the are against but do not remember hold a reference count (as that would pin the network namespace). So we currently have a small window where the reference count on a network namespace may be incremented when opening a /proc file when it has already gone to zero. To fix this introduce maybe_get_net and get_proc_net. maybe_get_net increments the network namespace reference count only if it is greater then zero, ensuring we don't increment a reference count after it has gone to zero. get_proc_net handles all of the magic to go from a proc inode to the network namespace instance and call maybe_get_net on it. PROC_NET the old accessor is removed so that we don't get confused and use the wrong helper function. Then I fix up the callers to use get_proc_net and handle the case case where get_proc_net returns NULL. In that case I return -ENXIO because effectively the network namespace has already gone away so the files we are trying to access don't exist anymore. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Acked-by: Paul E. McKenney <paulmck@us.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[NETLINK]: Introduce nested and byteorder flag to netlink attributeThomas Graf1-5/+5
This change allows the generic attribute interface to be used within the netfilter subsystem where this flag was initially introduced. The byte-order flag is yet unused, it's intended use is to allow automatic byte order convertions for all atomic types. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[NET]: Support multiple network namespaces with netlinkEric W. Biederman2-28/+80
Each netlink socket will live in exactly one network namespace, this includes the controlling kernel sockets. This patch updates all of the existing netlink protocols to only support the initial network namespace. Request by clients in other namespaces will get -ECONREFUSED. As they would if the kernel did not have the support for that netlink protocol compiled in. As each netlink protocol is updated to be multiple network namespace safe it can register multiple kernel sockets to acquire a presence in the rest of the network namespaces. The implementation in af_netlink is a simple filter implementation at hash table insertion and hash table look up time. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[NET]: Make socket creation namespace safe.Eric W. Biederman1-6/+9
This patch passes in the namespace a new socket should be created in and has the socket code do the appropriate reference counting. By virtue of this all socket create methods are touched. In addition the socket create methods are modified so that they will fail if you attempt to create a socket in a non-default network namespace. Failing if we attempt to create a socket outside of the default network namespace ensures that as we incrementally make the network stack network namespace aware we will not export functionality that someone has not audited and made certain is network namespace safe. Allowing us to partially enable network namespaces before all of the exotic protocols are supported. Any protocol layers I have missed will fail to compile because I now pass an extra parameter into the socket creation code. [ Integrated AF_IUCV build fixes from Andrew Morton... -DaveM ] Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[NET]: Make /proc/net per network namespaceEric W. Biederman1-1/+2
This patch makes /proc/net per network namespace. It modifies the global variables proc_net and proc_net_stat to be per network namespace. The proc_net file helpers are modified to take a network namespace argument, and all of their callers are fixed to pass &init_net for that argument. This ensures that all of the /proc/net files are only visible and usable in the initial network namespace until the code behind them has been updated to be handle multiple network namespaces. Making /proc/net per namespace is necessary as at least some files in /proc/net depend upon the set of network devices which is per network namespace, and even more files in /proc/net have contents that are relevant to a single network namespace. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[NETLINK]: use container_of insteadDenis Cheng1-1/+1
This could make future redesign of struct netlink_sock easier. Signed-off-by: Denis Cheng <crquan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-24[GENETLINK]: Correctly report errors while registering a multicast groupThomas Graf1-1/+1
Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-24[GENETLINK]: Fix adjustment of number of multicast groupsThomas Graf1-1/+1
The current calculation of the maximum number of genetlink multicast groups seems odd, fix it. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-24[GENETLINK]: Fix race in genl_unregister_mc_groups()Thomas Graf1-8/+16
family->mcast_groups is protected by genl_lock so it must be held while accessing the list in genl_unregister_mc_groups(). Requires adding a non-locking variant of genl_unregister_mc_group(). Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-18[GENETLINK]: Dynamic multicast groups.Johannes Berg1-7/+228
Introduce API to dynamically register and unregister multicast groups. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Acked-by: Patrick McHardy <kaber@trash.net> Acked-by: Jamal Hadi Salim <hadi@cyberus.ca> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-18[NETLIKN]: Allow removing multicast groups.Johannes Berg1-12/+45
Allow kicking listeners out of a multicast group when necessary (for example if that group is going to be removed.) Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Acked-by: Patrick McHardy <kaber@trash.net> Acked-by: Jamal Hadi Salim <hadi@cyberus.ca> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-18[NETLINK]: allocate group bitmaps dynamicallyJohannes Berg1-24/+82
Allow changing the number of groups for a netlink family after it has been created, use RCU to protect the listeners bitmap keeping netlink_has_listeners() lock-free. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Acked-by: Patrick McHardy <kaber@trash.net> Acked-by: Jamal Hadi Salim <hadi@cyberus.ca> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-18[NETLINK]: negative groups in netlink_setsockoptJohannes Berg1-2/+3
Reading netlink_setsockopt it's not immediately clear why there isn't a bug when you pass in negative numbers, the reason being that the >= comparison is really unsigned although 'val' is signed because nlk->ngroups is unsigned. Make 'val' unsigned too. [ Update the get_user() cast to match. --DaveM ] Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10[NET]: Make all initialized struct seq_operations const.Philippe De Muyter1-1/+1
Make all initialized struct seq_operations in net/ const Signed-off-by: Philippe De Muyter <phdm@macqel.be> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-10[NETLINK]: attr: add nested compat attribute typePatrick McHardy1-0/+11
Add a nested compat attribute type that can be used to convert attributes that contain a structure to nested attributes in a backwards compatible way. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-06-07[NETLINK]: Mark netlink policies constPatrick McHardy2-5/+5
Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-05-08header cleaning: don't include smp_lock.h when not usedRandy Dunlap1-1/+0
Remove includes of <linux/smp_lock.h> where it is not used/needed. Suggested by Al Viro. Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc, sparc64, and arm (all 59 defconfigs). Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-04[NETLINK]: Remove bogus BUG_ONPatrick McHardy1-1/+0
Remove bogus BUG_ON(mutex_is_locked(nlk_sk(sk)->cb_mutex)), when the netlink_kernel_create caller specifies an external mutex it might validly be locked. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-05-03[NETLINK]: Fix use after free in netlink_recvmsgPatrick McHardy1-4/+2
When the user passes in MSG_TRUNC the skb is used after getting freed. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-05-03[NETLINK]: Kill CB only when socket is unusedHerbert Xu1-14/+15
Since we can still receive packets until all references to the socket are gone, we don't need to kill the CB until that happens. This also aligns ourselves with the receive queue purging which happens at that point. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-26[NETLINK]: Possible cleanups.Adrian Bunk1-2/+2
- make the following needlessly global variables static: - core/rtnetlink.c: struct rtnl_msg_handlers[] - netfilter/nf_conntrack_proto.c: struct nf_ct_protos[] - make the following needlessly global functions static: - core/rtnetlink.c: rtnl_dump_all() - netlink/af_netlink.c: netlink_queue_skip() Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[NETLINK]: don't reinitialize callback mutexPatrick McHardy1-2/+6
Don't reinitialize the callback mutex the netlink_kernel_create caller handed in, it is supposed to already be initialized and could already be held by someone. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[NETLINK]: Switch cb_lock spinlock to mutex and allow to override itPatrick McHardy2-16/+24
Switch cb_lock to mutex and allow netlink kernel users to override it with a subsystem specific mutex for consistent locking in dump callbacks. All netlink_dump_start users have been audited not to rely on any side-effects of the previously used spinlock. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[NETLINK]: introduce NLA_BINARY typeJohannes Berg1-0/+5
This patch introduces a new NLA_BINARY attribute policy type with the verification of simply checking the maximum length of the payload. It also fixes a small typo in the example. Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[NETLINK]: Directly return -EINTR from netlink_dump_start()Thomas Graf2-6/+8
Now that all users of netlink_dump_start() use netlink_run_queue() to process the receive queue, it is possible to return -EINTR from netlink_dump_start() directly, therefore simplying the callers. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[NETLINK]: Remove error pointer from netlink message handlerThomas Graf2-45/+32
The error pointer argument in netlink message handlers is used to signal the special case where processing has to be interrupted because a dump was started but no error happened. Instead it is simpler and more clear to return -EINTR and have netlink_run_queue() deal with getting the queue right. nfnetlink passed on this error pointer to its subsystem handlers but only uses it to signal the start of a netlink dump. Therefore it can be removed there as well. This patch also cleans up the error handling in the affected message handlers to be consistent since it had to be touched anyway. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[NETLINK]: Ignore control messages directly in netlink_run_queue()Thomas Graf2-6/+4
Changes netlink_rcv_skb() to skip netlink controll messages and don't pass them on to the message handler. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[NETLINK]: Ignore !NLM_F_REQUEST messages directly in netlink_run_queue()Thomas Graf2-5/+8
netlink_rcv_skb() is changed to skip messages which don't have the NLM_F_REQUEST bit to avoid every netlink family having to perform this check on their own. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[NETLINK]: Remove unused groups variableThomas Graf1-2/+0
Leftover from dynamic multicast groups allocation work. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[NETLINK]: Introduce nlmsg_hdr() helperArnaldo Carvalho de Melo1-1/+1
For the common "(struct nlmsghdr *)skb->data" sequence, so that we reduce the number of direct accesses to skb->data and for consistency with all the other cast skb member helpers. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[SK_BUFF]: Convert skb->end to sk_buff_data_tArnaldo Carvalho de Melo1-1/+1
Now to convert the last one, skb->data, that will allow many simplifications and removal of some of the offset helpers. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[SK_BUFF]: Convert skb->tail to sk_buff_data_tArnaldo Carvalho de Melo1-1/+1
So that it is also an offset from skb->head, reduces its size from 8 to 4 bytes on 64bit architectures, allowing us to combine the 4 bytes hole left by the layer headers conversion, reducing struct sk_buff size to 256 bytes, i.e. 4 64byte cachelines, and since the sk_buff slab cache is SLAB_HWCACHE_ALIGN... :-) Many calculations that previously required that skb->{transport,network, mac}_header be first converted to a pointer now can be done directly, being meaningful as offsets or pointers. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[SK_BUFF]: Introduce skb_reset_transport_header(skb)Arnaldo Carvalho de Melo1-1/+1
For the common, open coded 'skb->h.raw = skb->data' operation, so that we can later turn skb->h.raw into a offset, reducing the size of struct sk_buff in 64bit land while possibly keeping it as a pointer on 32bit. This one touches just the most simple cases: skb->h.raw = skb->data; skb->h.raw = {skb_push|[__]skb_pull}() The next ones will handle the slightly more "complex" cases. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[TCP/DCCP/RANDOM]: Remove unused exports.Adrian Bunk1-1/+0
This patch removes the following not or no longer used exports: - drivers/char/random.c: secure_tcp_sequence_number - net/dccp/options.c: sysctl_dccp_feat_sequence_window - net/netlink/af_netlink.c: netlink_set_err Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[NETLINK]: Mirror UDP MSG_TRUNC semantics.David S. Miller1-0/+3
If the user passes MSG_TRUNC in via msg_flags, return the full packet size not the truncated size. Idea from Herbert Xu and Thomas Graf. Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-18[NETLINK]: Don't attach callback to a going-away netlink socketDenis Lunev1-3/+3
There is a race between netlink_dump_start() and netlink_release() that can lead to the situation when a netlink socket with non-zero callback is freed. Here it is: CPU1: CPU2 netlink_release(): netlink_dump_start(): sk = netlink_lookup(); /* OK */ netlink_remove(); spin_lock(&nlk->cb_lock); if (nlk->cb) { /* false */ ... } spin_unlock(&nlk->cb_lock); spin_lock(&nlk->cb_lock); if (nlk->cb) { /* false */ ... } nlk->cb = cb; spin_unlock(&nlk->cb_lock); ... sock_orphan(sk); /* * proceed with releasing * the socket */ The proposal it to make sock_orphan before detaching the callback in netlink_release() and to check for the sock to be SOCK_DEAD in netlink_dump_start() before setting a new callback. Signed-off-by: Denis Lunev <den@openvz.org> Signed-off-by: Kirill Korotaev <dev@openvz.org> Signed-off-by: Pavel Emelianov <xemul@openvz.org> Acked-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-12[PATCH] mark struct file_operations const 8Arjan van de Ven1-1/+1
Many struct file_operations in the kernel can be "const". Marking them const moves these to the .rodata section, which avoids false sharing with potential dirty data. In addition it'll catch accidental writes at compile time to these shared resources. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>