If a process issues an URB from userspace and (starts to) terminate
before the URB comes back, we run into the issue described above. This
is because the urb saves a pointer to "current" when it is posted to the
device, but there's no guarantee that this pointer is still valid
afterwards.
In fact, there are three separate issues:
1) the pointer to "current" can become invalid, since the task could be
completely gone when the URB completion comes back from the device.
2) Even if the saved task pointer is still pointing to a valid task_struct,
task_struct->sighand could have gone meanwhile.
3) Even if the process is perfectly fine, permissions may have changed,
and we can no longer send it a signal.
So what we do instead, is to save the PID and uid's of the process, and
introduce a new kill_proc_info_as_uid() function.
Signed-off-by: Harald Welte <laforge@gnumonks.org>
[ Fixed up types and added symbol exports ]
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The following patch makes swsusp avoid the possible temporary corruption
of page translation tables during resume on x86-64. This is achieved by
creating a copy of the relevant page tables that will not be modified by
swsusp and can be safely used by it on resume.
The problem is that during resume on x86-64 swsusp may temporarily
corrupt the page tables used for the direct mapping of RAM. If that
happens, a page fault occurs and cannot be handled properly, which leads
to the solid hang of the affected system. This leads to the loss of the
system's state from before suspend and may result in the loss of data or
the corruption of filesystems, so it is a serious issue. Also, it
appears to happen quite often (for me, as often as 50% of the time).
The problem is related to the fact that (at least) one of the PMD
entries used in the direct memory mapping (starting at PAGE_OFFSET)
points to a page table the physical address of which is much greater
than the physical address of the PMD entry itself. Moreover,
unfortunately, the physical address of the page table before suspend
(i.e. the one stored in the suspend image) happens to be different to
the physical address of the corresponding page table used during resume
(i.e. the one that is valid right before swsusp_arch_resume() in
arch/x86_64/kernel/suspend_asm.S is executed). Thus while the image is
restored, the "offending" PMD entry gets overwritten, so it does not
point to the right physical address any more (i.e. there's no page
table at the address pointed to by it, because it points to the address
the page table has been at during suspend). Consequently, if the PMD
entry is used later on, and it _is_ used in the process of copying the
image pages, a page fault occurs, but it cannot be handled in the normal
way and the system hangs.
In principle we can call create_resume_mapping() from
swsusp_arch_resume() (ie. from suspend_asm.S), but then the memory
allocations in create_resume_mapping(), resume_pud_mapping(), and
resume_pmd_mapping() must be made carefully so that we use _only_
NosaveFree pages in them (the other pages are overwritten by the loop in
swsusp_arch_resume()). Additionally, we are in atomic context at that
time, so we cannot use GFP_KERNEL. Moreover, if one of the allocations
fails, we should free all of the allocated pages, so we need to trace
them somehow.
All of this is done in the appended patch, except that the functions
populating the page tables are located in arch/x86_64/kernel/suspend.c
rather than in init.c. It may be done in a more elegan way in the
future, with the help of some swsusp patches that are in the works now.
[AK: move some externs into headers, renamed a function]
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- added typedef unsigned int __nocast gfp_t;
- replaced __nocast uses for gfp flags with gfp_t - it gives exactly
the same warnings as far as sparse is concerned, doesn't change
generated code (from gcc point of view we replaced unsigned int with
typedef) and documents what's going on far better.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The attached patch splits key permissions checking out of key-ui.h and
moves it into a .c file. It's quite large and called quite a lot, and
it's about to get bigger with the addition of LSM support for keys...
key_any_permission() is also discarded as it's no longer used.
Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix nocast sparse warnings:
include/linux/textsearch.h:165:57: warning: implicit cast to nocast type
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix implicit nocast warnings in connector code:
drivers/connector/connector.c:102:24: warning: implicit cast to nocast type
drivers/connector/connector.c:114:45: warning: implicit cast to nocast type
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix implicit nocast warnings in atm code:
net/atm/atm_misc.c:35:44: warning: implicit cast to nocast type
drivers/atm/fore200e.c:183:33: warning: implicit cast to nocast type
Also use kzalloc() instead of kmalloc().
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This redoes the n_ports logic I proposed before as a bitmask.
ata_pci_init_native_mode is now used with a mask allowing for mixed mode
stuff later on. ata_pci_init_legacy_port is called with port number and
does one port now not two. Instead it is called twice by the ata init
logic which cleans both of them up.
There are stil limits in the original code left over
- IRQ/port mapping for legacy mode should be arch specific values
- You can have one legacy mode IDE adapter per PCI root bridge on some systems
- Doesn't handle mixed mode devices yet (but is now a lot closer to it)
The following patch renames __in_dev_get() to __in_dev_get_rtnl() and
introduces __in_dev_get_rcu() to cover the second case.
1) RCU with refcnt should use in_dev_get().
2) RCU without refcnt should use __in_dev_get_rcu().
3) All others must hold RTNL and use __in_dev_get_rtnl().
There is one exception in net/ipv4/route.c which is in fact a pre-existing
race condition. I've marked it as such so that we remember to fix it.
This patch is based on suggestions and prior work by Suzanne Wood and
Paul McKenney.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Arnaldo and I agreed it could be applied now, because I have other
pending patches depending on this one (Thank you Arnaldo)
(The other important patch moves skc_refcnt in a separate cache line,
so that the SMP/NUMA performance doesnt suffer from cache line ping pongs)
1) First some performance data :
--------------------------------
tcp_v4_rcv() wastes a *lot* of time in __inet_lookup_established()
The most time critical code is :
sk_for_each(sk, node, &head->chain) {
if (INET_MATCH(sk, acookie, saddr, daddr, ports, dif))
goto hit; /* You sunk my battleship! */
}
The sk_for_each() does use prefetch() hints but only the begining of
"struct sock" is prefetched.
As INET_MATCH first comparison uses inet_sk(__sk)->daddr, wich is far
away from the begining of "struct sock", it has to bring into CPU
cache cold cache line. Each iteration has to use at least 2 cache
lines.
This can be problematic if some chains are very long.
2) The goal
-----------
The idea I had is to change things so that INET_MATCH() may return
FALSE in 99% of cases only using the data already in the CPU cache,
using one cache line per iteration.
3) Description of the patch
---------------------------
Adds a new 'unsigned int skc_hash' field in 'struct sock_common',
filling a 32 bits hole on 64 bits platform.
struct sock_common {
unsigned short skc_family;
volatile unsigned char skc_state;
unsigned char skc_reuse;
int skc_bound_dev_if;
struct hlist_node skc_node;
struct hlist_node skc_bind_node;
atomic_t skc_refcnt;
+ unsigned int skc_hash;
struct proto *skc_prot;
};
Store in this 32 bits field the full hash, not masked by (ehash_size -
1) Using this full hash as the first comparison done in INET_MATCH
permits us immediatly skip the element without touching a second cache
line in case of a miss.
Suppress the sk_hashent/tw_hashent fields since skc_hash (aliased to
sk_hash and tw_hash) already contains the slot number if we mask with
(ehash_size - 1)
File include/net/inet_hashtables.h
64 bits platforms :
#define INET_MATCH(__sk, __hash, __cookie, __saddr, __daddr, __ports, __dif)\
(((__sk)->sk_hash == (__hash))
((*((__u64 *)&(inet_sk(__sk)->daddr)))== (__cookie)) && \
((*((__u32 *)&(inet_sk(__sk)->dport))) == (__ports)) && \
(!((__sk)->sk_bound_dev_if) || ((__sk)->sk_bound_dev_if == (__dif))))
32bits platforms:
#define TCP_IPV4_MATCH(__sk, __hash, __cookie, __saddr, __daddr, __ports, __dif)\
(((__sk)->sk_hash == (__hash)) && \
(inet_sk(__sk)->daddr == (__saddr)) && \
(inet_sk(__sk)->rcv_saddr == (__daddr)) && \
(!((__sk)->sk_bound_dev_if) || ((__sk)->sk_bound_dev_if == (__dif))))
- Adds a prefetch(head->chain.first) in
__inet_lookup_established()/__tcp_v4_check_established() and
__inet6_lookup_established()/__tcp_v6_check_established() and
__dccp_v4_check_established() to bring into cache the first element of the
list, before the {read|write}_lock(&head->lock);
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Acked-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
I've found the problem in general. It affects any 64-bit
architecture. The problem occurs when you change the system time.
Suppose that when you boot your system clock is forward by a day.
This gets recorded down in skb_tv_base. You then wind the clock back
by a day. From that point onwards the offset will be negative which
essentially overflows the 32-bit variables they're stored in.
In fact, why don't we just store the real time stamp in those 32-bit
variables? After all, we're not going to overflow for quite a while
yet.
When we do overflow, we'll need a better solution of course.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use '#ifdef' consistently on __KERNEL__. This was reported as bug #5340
(isn't easier to send a fix than report the bug?!)
Signed-off-by: Diego Calleja <diegocg@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Only one of the run or kick path is supposed to put an iocb on the run
list. If both of them do it than one of them can end up referencing a
freed iocb. The kick path could delete the task_list item from the wait
queue before getting the ctx_lock and putting the iocb on the run list.
The run path was testing the task_list item outside the lock so that it
could catch ki_retry methods that return -EIOCBRETRY *without* putting the
iocb on a wait queue and promising to call kick_iocb. This unlocked check
could then race with the kick path to cause both to try and put the iocb on
the run list.
The patch stops the run path from testing task_list by requring that any
ki_retry that returns -EIOCBRETRY *must* guarantee that kick_iocb() will be
called in the future. aio_p{read,write}, the only in-tree -EIOCBRETRY
users, are updated.
Signed-off-by: Zach Brown <zach.brown@oracle.com>
Signed-off-by: Benjamin LaHaise <bcrl@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Roland points out that the flags end up having non-obvious dependencies
elsewhere, so revert aa55a08687 and add
some comments about why things are as they are.
We'll just have to fix up the broken comparisons. Roland has a patch.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
do_signal_stop:
for_each_thread(t) {
if (t->state < TASK_STOPPED)
++sig->group_stop_count;
}
However, TASK_NONINTERACTIVE > TASK_STOPPED, so this loop will not
count TASK_INTERRUPTIBLE | TASK_NONINTERACTIVE threads.
See also wait_task_stopped(), which checks ->state > TASK_STOPPED.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
[ We really probably should always use the appropriate bitmasks to test
task states, not do it like this. Using something like
#define TASK_RUNNABLE (TASK_RUNNING | TASK_INTERRUPTIBLE | \
TASK_UNINTERRUPTIBLE | TASK_NONINTERACTIVE)
and then doing "if (task->state & TASK_RUNNABLE)" or similar. But the
ordering of the task states is historical, and keeping the ordering
does make sense regardless. ]
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The attached patch adds extra permission grants to keys for the possessor of a
key in addition to the owner, group and other permissions bits. This makes
SUID binaries easier to support without going as far as labelling keys and key
targets using the LSM facilities.
This patch adds a second "pointer type" to key structures (struct key_ref *)
that can have the bottom bit of the address set to indicate the possession of
a key. This is propagated through searches from the keyring to the discovered
key. It has been made a separate type so that the compiler can spot attempts
to dereference a potentially incorrect pointer.
The "possession" attribute can't be attached to a key structure directly as
it's not an intrinsic property of a key.
Pointers to keys have been replaced with struct key_ref *'s wherever
possession information needs to be passed through.
This does assume that the bottom bit of the pointer will always be zero on
return from kmem_cache_alloc().
The key reference type has been made into a typedef so that at least it can be
located in the sources, even though it's basically a pointer to an undefined
type. I've also renamed the accessor functions to be more useful, and all
reference variables should now end in "_ref".
Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Changes:
s/PIO_ST_/HSM_ST_/ and s/pio_task_state/hsm_task_state/.
Signed-off-by: Albert Lee <albertcc@tw.ibm.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
The following is generated when compiling a
recent (2.6.14-rc2-git5) kernel configured for
ARM, with GCC4.
CC init/main.o
In file included from include/linux/netdevice.h:29,
from include/net/sock.h:48,
from init/main.c:50:
include/linux/if_ether.h:114: error: array type has incomplete element type
It seems that if CONFIG_SYSCTL is not set, then
the compiler will throw an error due to the definition
of the ether_table[] array
Attached is a solution to the problem
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Written by Adrian Sun (asun@darksunrising.com).
Ported to 2.6.x by Tom 'spot' Callaway <tcallawa@redhat.com>.
Further cleaned up and integrated by David S. Miller
Signed-off-by: David S. Miller <davem@davemloft.net>
Place them on separate cache lines in SMP to lower memory bouncing
between multiple CPU accessing the device.
- One part is mostly used on receive path (including
eth_type_trans()) (poll_list, poll, quota, weight, last_rx,
dev_addr, broadcast)
- One part is mostly used on queue transmit path (qdisc)
(queue_lock, qdisc, qdisc_sleeping, qdisc_list, tx_queue_len)
- One part is mostly used on xmit path (device)
(xmit_lock, xmit_lock_owner, priv, hard_start_xmit, trans_start)
'features' is placed outside of these hot points, in a location that
may be shared by all cpus (because mostly read)
name_hlist is moved close to name[IFNAMSIZ] to speedup __dev_get_by_name()
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When you've enabled conntrack and NAT as a module (standard case in all
distributions), and you've also enabled the new conntrack netlink
interface, loading ip_conntrack_netlink.ko will auto-load iptable_nat.ko.
This causes a huge performance penalty, since for every packet you iterate
the nat code, even if you don't want it.
This patch splits iptable_nat.ko into the NAT core (ip_nat.ko) and the
iptables frontend (iptable_nat.ko). Threfore, ip_conntrack_netlink.ko will
only pull ip_nat.ko, but not the frontend. ip_nat.ko will "only" allocate
some resources, but not affect runtime performance.
This separation is also a nice step in anticipation of new packet filters
(nf-hipac, ipset, pkttables) being able to use the NAT core.
Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
If input message rate from userspace is too high, do not drop them,
but try to deliver using work queue allocation.
Failing there is some kind of congestion control.
It also removes warn_on on this condition, which scares people.
Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
- Added a missing TO_NATIVE call to scripts/mod/file2alias.c:do_pcmcia_entry()
- Add an alignment attribute to struct pcmcia_device_no to solve an alignment
issue seen when cross-compiling on x86 for m68k.
Signed-off-by: Kars de Jong <jongk@linux-m68k.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Support some more TI cardbus bridges. most of them are multifunction
devices which adds 1394 controllers, smartcard readers etc. this could
also help with the various problems with the XX21 controllers seen on the
linux-pcmcia list.
Signed-off-by: Daniel Ritz <daniel.ritz@gmx.ch>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Echo Audio cardbus products are known to be incompatible with EnE bridges.
in order to maybe solve the problem a EnE specific test bit has to be set,
another cleared...but other setups have a good chance to break when just
forcing the bits. so do the whole thingy automatically.
The patch adds a hook in cb_alloc() that allows special tuning for the
different chipsets. for ene just match the Echo products and set/clear the
test bits, defaults to do the same thing as w/o the patch to not break
working setups.
Signed-off-by: Daniel Ritz <daniel.ritz@gmx.ch>
Cc: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
This patch fixes a number of bugs. It cannot be reasonably split up in
multiple fixes, since all bugs interact with each other and affect the same
function:
Bug #1:
The event cache code cannot be called while a lock is held. Therefore, the
call to ip_conntrack_event_cache() within ip_ct_refresh_acct() needs to be
moved outside of the locked section. This fixes a number of 2.6.14-rcX
oops and deadlock reports.
Bug #2:
We used to call ct_add_counters() for unconfirmed connections without
holding a lock. Since the add operations are not atomic, we could race
with another CPU.
Bug #3:
ip_ct_refresh_acct() lost REFRESH events in some cases where refresh
(and the corresponding event) are desired, but no accounting shall be
performed. Both, evenst and accounting implicitly depended on the skb
parameter bein non-null. We now re-introduce a non-accounting
"ip_ct_refresh()" variant to explicitly state the desired behaviour.
Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
In the lead up to 2.6.13 I fixed a large number of reboot problems by
making the calling conventions consistent. Despite checking and double
checking my work it appears I missed an obvious one.
This first patch simply refactors the reboot routines so all of the
preparation for various kinds of reboots are in their own functions.
Making it very hard to get the various kinds of reboot out of sync.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
add the helper and use it instead of open coding the klist_node_attached() check
(which is a layering violation IMHO)
idea by Alan Stern.
Signed-off-by: Daniel Ritz <daniel.ritz@gmx.ch>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
