Let's suppose we have 2 threads in thread group:
A - does coredump
B - has pending SIGSTOP
thread A thread B
do_coredump: get_signal_to_deliver:
lock(->sighand)
->signal->flags = SIGNAL_GROUP_EXIT
unlock(->sighand)
lock(->sighand)
signr = dequeue_signal()
->signal->flags |= SIGNAL_STOP_DEQUEUED
return SIGSTOP;
do_signal_stop:
unlock(->sighand)
coredump_wait:
zap_threads:
lock(tasklist_lock)
send SIGKILL to B
// signal_wake_up() does nothing
unlock(tasklist_lock)
lock(tasklist_lock)
lock(->sighand)
re-check sig->flags & SIGNAL_STOP_DEQUEUED, yes
set_current_state(TASK_STOPPED);
finish_stop:
schedule();
// ->state == TASK_STOPPED
wait_for_completion(&startup_done)
// waits for complete() from B,
// ->state == TASK_UNINTERRUPTIBLE
We can't wake up 'B' in any way:
SIGCONT will be ignored because handle_stop_signal() sees
->signal->flags & SIGNAL_GROUP_EXIT.
sys_kill(SIGKILL)->__group_complete_signal() will choose
uninterruptible 'A', so it can't help.
sys_tkill(B, SIGKILL) will be ignored by specific_send_sig_info()
because B already has pending SIGKILL.
This scenario is not possbile if 'A' does do_group_exit(), because
it sets sig->flags = SIGNAL_GROUP_EXIT and delivers SIGKILL to
subthreads atomically, holding both tasklist_lock and sighand->lock.
That means that do_signal_stop() will notice !SIGNAL_STOP_DEQUEUED
after re-locking ->sighand. And it is not possible to any other
thread to re-add SIGNAL_STOP_DEQUEUED later, because dequeue_signal()
can only return SIGKILL.
I think it is better to change do_coredump() to do sigaddset(SIGKILL)
and signal_wake_up() under sighand->lock, but this patch is much
simpler.
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The nameidata "last.name" is always allocated with "__getname()", and
should always be free'd with "__putname()".
Using "putname()" without the underscores will leak memory, because the
allocation will have been hidden from the AUDITSYSCALL code.
Arguably the real bug is that the AUDITSYSCALL code is really broken,
but in the meantime this fixes the problem people see.
Reported by Robert Derr, patch by Rick Lindsley.
Acked-by: Al Viro <viro@ftp.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
I've noticed a kernel hang during a storm of CMC interrupts, which was
tracked down to the continual execution of the interrupt handler.
There's code in the CMC handler that's supposed to disable CMC
interrupts and switch to polling mode when it sees a bunch of CMCs.
Because disabling CMCs across all CPUs isn't safe in interrupt context,
the disable is done with a schedule_work(). But with continual CMC
interrupts, the schedule_work() never gets executed.
The following patch immediately disables CMC interrupts for the current
CPU. This then allows (at least) one CPU to ignore CMC interrupts,
execute the schedule_work() code, and disable CMC interrupts on the rest
of the CPUs.
Acked-by: Keith Owens <kaos@sgi.com>
Signed-off-by: Bryan Sutula <Bryan.Sutula@hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
drivers/mfd/ucb1x00-core.c:555: error: static declaration of 'ucb1x00_class' follows non-static declaration
drivers/mfd/ucb1x00.h:109: error: previous declaration of 'ucb1x00_class' was here
Since ucb1x00_class isn't used by anything, remove the extern
declaration and the symbol export.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
By allocating early memory for the firmware page tables, we
can write over the beginning of the initrd image.
So what we do now is:
1) Read in firmware translations table while still on the
firmware's trap table.
2) Switch to Linux trap table.
3) Init bootmem.
4) Build firmware page tables using __alloc_bootmem().
And this keeps the initrd from being clobbered.
Signed-off-by: David S. Miller <davem@davemloft.net>
Patch from Catalin Marinas
There is no reason to not allow these config options. They are useful when
the hardware has problems.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Remove some duplicated items due to the inclusion of the general
drivers/Kconfig file. These are now taken from drivers/char/Kconfig,
and can be turned off there as well (which is desirable sometimes).
Signed-off-by: Martin Habets <errandir_news@mph.eclipse.co.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since changeset 98a82febb6 AX.25 is passing
received IP and ARP packets to the stack through netif_rx() but we don't
set the skb->mac.raw to right value which may result in a crash with
applications that use a packet socket.
Signed-off-by: Ralf Baechle DL5RB <ralf@linux-mips.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Here is a patch that adds a helper called xfrm_policy_id2dir to
document the fact that the policy direction can be and is derived
from the index.
This is based on a patch by YOSHIFUJI Hideaki and 210313105@suda.edu.cn.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Timer set up by pneigh_enqueue() ended up calling ndisc_rcv()
via pndisc_redo(), which clears LOCALLY_ENQUEUED flag in
NEIGH_CB(skb) and NS was queued again.
Let's call ndisc_recv_ns() directly to avoid the loop.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Missing parenthesis in causes BIC to be slow in increasing congestion
window.
Spotted by Injong Rhee.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-Off-By: Yan Zheng <yanzheng@21cn.com>
Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Acked-by: David L Stevens <dlstevens@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Older Macs which uses the VIA chip timers to calibrate the timebase used
some code that wouldn't work if HZ wasn't divisible by 100...
This fixes it at least for 250. Not totally perfect but should be
enough for now (so it at least works with the default value which is now
250).
There is still a potential issue with the core using CLOCK_TICK_RATE to
maintain xtime and CLOCK_TICK_RATE value on ppc32 is pure crap, but that
is a different problem, this patch at least brings us back to our
previous situation.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
If we switch extern inline to static inline, we'd better switch the
pre-declarations we use to say that these puppies have
__attribute_const__ on them.
Otherwise we get extern declaration followed by static inline one.
Which makes gcc unhappy, and for a good reason...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix implicit nocast warnings in xfrm code:
net/xfrm/xfrm_policy.c:232:47: warning: implicit cast to nocast type
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
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 nocast sparse warnings:
net/rxrpc/call.c:2013:25: warning: implicit cast to nocast type
net/rxrpc/connection.c:538:46: warning: implicit cast to nocast type
net/sunrpc/sched.c:730:36: warning: implicit cast to nocast type
net/sunrpc/sched.c:734:56: 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 net/key code:
net/key/af_key.c:195:27: warning: implicit cast to nocast type
net/key/af_key.c:1439:28: 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 nfnetlink code:
net/netfilter/nfnetlink.c:204:43: warning: implicit cast to nocast type
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
From: Randy Dunlap <rdunlap@xenotime.net>
Fix implicit nocast warnings in ip_vs code:
net/ipv4/ipvs/ip_vs_app.c:631:54: 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 decnet code:
net/decnet/af_decnet.c:458:40: warning: implicit cast to nocast type
net/decnet/dn_nsp_out.c:125:35: warning: implicit cast to nocast type
net/decnet/dn_nsp_out.c:219:29: 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 bonding code:
drivers/net/bonding/bond_main.c:1302:49: 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>
The orinoco driver can send uninitialized data exposing random pieces of
the system memory. This happens because data is not padded with zeroes
when its length needs to be increased.
Reported by Meder Kydyraliev <meder@o0o.nu>
Signed-off-by: Pavel Roskin <proski@gnu.org>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
Macro ended up backwards during one of cleanups. Found by Alessandro Zummo.
Signed-off-by: Deepak Saxena <dsaxena@plexity.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Drop global bit from early low mappings
Suggested by Linus, originally also proposed by Suresh.
This fixes a race condition with early start of udev, originally
tracked down by Suresh B. Siddha. The problem was that switching
to the user space VM would not clear the global low mappings
for the beginning of memory, which lead to memory corruption.
Drop the global bits.
The kernel mapping stays global because it should stay constant.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
No need to align struct inet_ehash_bucket on a 8 bytes boundary.
On 32 bits Uniprocessor, that's a waste of 4 bytes per struct (50 %)
On other platforms, the attribute is useless, natual alignement is already 8.
platform | Size before | Size after patch
-------------+-------------+------------------
32 bits, UP | 8 | 4
32 bits, SMP | 8 | 8
64 bits, UP | 8 | 8
64 bits, SMP | 16 | 16
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of code patching to handle the page size fields in
the context registers, just use variables from which we get
the proper values.
Signed-off-by: David S. Miller <davem@davemloft.net>
Patch from Nicolas Pitre
If gcc decides to assign lr to %0 we're screwed.
Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Nicolas Pitre
The cmpxchg emulation syscall needs write access.
Signed-off-by: Nicolas Pitre <nico@cam.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Sascha Hauer
Current implementation of imx_gpio_mode does not allow to
configure all alternate routing possibilities of the i.MX. With
this patch every bit in the gpio setup registers has a
corresponding bit in the gpio_mode parameter, so every routing
should be possible now.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Patch from Sascha Hauer
After coming out of idle mode the h720x goes into slow mode. Switch
it back to run mode.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The old code had the IP and SP coming from the registers in the thread
struct, which are completely wrong since those are the userspace
registers. This fixes that by pulling the correct values from the
jmp_buf in which the kernel state of each thread is stored.
Signed-off-by: Allan Graves <allan.graves@oracle.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Al's build tidying missed one bit from me - without this UML doesn't boot.
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Acked-by: Al Viro <viro@ftp.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
bfs_fill_super() walks the inode table to get the bitmap of free inodes
and collect stats. It has no business using iget() for that - it's a
lot of extra work, extra icache pollution and more complex code.
Switched to walking the damn thing directly.
Note: that also allows to kill ->i_dsk_ino in there - separate patch if
Tigran can confirm that this field can be zero only for deleted inodes
(i.e. something that could only be found during that scan and not by
normal lookups).
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
On several failure exits in ibmtr we end up doing kfree() on dev->priv,
with dev allocated by alloc_trdev() and ->priv never reassigned.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
megaraid_sas depends on arch-specific indirect includes pulling
fs.h in; on alpha they do not.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The patch below introduces special thresholds to keep root node in the trie
large. This gives a flatter tree at the cost of a modest memory increase.
Overall it seems to be gain and this was also proposed by one the authors
of the paper in recent a seminar.
Main table after loading 123 k routes.
Aver depth: 3.30
Max depth: 9
Root-node size 12 bits
Total size: 4044 kB
With the patch:
Aver depth: 2.78
Max depth: 8
Root-node size 15 bits
Total size: 4150 kB
An increase of 8-10% was seen in forwading performance for an rDoS attack.
Signed-off-by: Robert Olsson <robert.olsson@its.uu.se>
Signed-off-by: David S. Miller <davem@davemloft.net>