kcalloc is supposed to be called with the count as its first argument and
the element size as the second.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Reduced version of the spelling cleanup patch.
Take out the confusing language in tcp_frto, and organize the
undocumented values.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix some of the defaults and attempt to clarify some language.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
Vegard Nossum reported a crash in kmem_cache_alloc():
BUG: unable to handle kernel paging request at da87d000
IP: [<c01991c7>] kmem_cache_alloc+0xc7/0xe0
*pde = 28180163 *pte = 1a87d160
Oops: 0002 [#1] PREEMPT SMP DEBUG_PAGEALLOC
Pid: 3850, comm: grep Not tainted (2.6.26-rc9-00059-gb190333 #5)
EIP: 0060:[<c01991c7>] EFLAGS: 00210203 CPU: 0
EIP is at kmem_cache_alloc+0xc7/0xe0
EAX: 00000000 EBX: da87c100 ECX: 1adad71a EDX: 6b6b6b6b
ESI: 00200282 EDI: da87d000 EBP: f60bfe74 ESP: f60bfe54
DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068
and analyzed it:
"The register %ecx looks innocent but is very important here. The disassembly:
mov %edx,%ecx
shr $0x2,%ecx
rep stos %eax,%es:(%edi) <-- the fault
So %ecx has been loaded from %edx... which is 0x6b6b6b6b/POISON_FREE.
(0x6b6b6b6b >> 2 == 0x1adadada.)
%ecx is the counter for the memset, from here:
memset(object, 0, c->objsize);
i.e. %ecx was loaded from c->objsize, so "c" must have been freed.
Where did "c" come from? Uh-oh...
c = get_cpu_slab(s, smp_processor_id());
This looks like it has very much to do with CPU hotplug/unplug. Is
there a race between SLUB/hotplug since the CPU slab is used after it
has been freed?"
Good analysis.
Yeah, it's possible that a caller of kmem_cache_alloc() -> slab_alloc()
can be migrated on another CPU right after local_irq_restore() and
before memset(). The inital cpu can become offline in the mean time (or
a migration is a consequence of the CPU going offline) so its
'kmem_cache_cpu' structure gets freed ( slab_cpuup_callback).
At some point of time the caller continues on another CPU having an
obsolete pointer...
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Reported-by: Vegard Nossum <vegard.nossum@gmail.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Kernel Bugzilla #11063 points out that on some architectures (e.g. x86_32)
exec'ing an ELF without a PT_GNU_STACK program header should default to an
executable stack; but this got broken by the unlimited argv feature because
stack vma is now created before the right personality has been established:
so breaking old binaries using nested function trampolines.
Therefore re-evaluate VM_STACK_FLAGS in setup_arg_pages, where stack
vm_flags used to be set, before the mprotect_fixup. Checking through
our existing VM_flags, none would have changed since insert_vm_struct:
so this seems safer than finding a way through the personality labyrinth.
Reported-by: pageexec@freemail.hu
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Clean up __migrate_task(): to just have separate "done" and "fail"
cases, instead of that "out" case with random error behavior.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
PREEMPT_RCU without HOTPLUG_CPU is broken. The rcu_online_cpu is called
to initially populate rcu_cpu_online_map with all online CPUs when the
hotplug event handler is installed, and also to populate the map with
CPUs as they come online. The former case is meant to happen with and
without HOTPLUG_CPU, but without HOTPLUG_CPU, the rcu_offline_cpu
function is no-oped -- while it still gets called, it does not set the
rcu CPU map.
With a blank RCU CPU map, grace periods get to tick by completely
oblivious to active RCU read side critical sections. This results in
free-before-grace bugs.
Fix is obvious once the problem is known. (Also, change __devinit to
__cpuinit so the function gets thrown away on !HOTPLUG_CPU kernels).
Signed-off-by: Nick Piggin <npiggin@suse.de>
Reported-and-tested-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
[ Nick is my personal hero of the day - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the long awaited ftrace.txt. It explains in quite detail how to
use ftrace and the various tracers.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The stack-glue merge changed the way we use flags in dlmglue in that we now
use the fs/dlm equivalents. Unfortunately, a merge error left the new flock
code only partially updated. This took a while to show up though, because
the lock level constants are actually identical between o2dlm and fs/dlm.
The *_CONVERT and *_NOQUEUE flags have different values though, which is
eventually causing a crash in flags_to_o2dlm().
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
When chainiv postpones requests it never calls their completion functions.
This causes symptoms such as memory leaks when IPsec is in use.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Add ioremap_default(), which gives a sane mapping without worrying about
type conflicts.
Use it in /dev/mem read in place of ioremap(), as with ioremap(),
any mapping of the region (other than UC_MINUS) will cause a conflict
and failure of /dev/mem read.
Should address the vbetest failure reported at:
http://bugzilla.kernel.org/show_bug.cgi?id=11057
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
I think we may have a race between try_to_wake_up() and
migrate_live_tasks() -> move_task_off_dead_cpu() when the later one
may end up looping endlessly.
Interrupts are enabled on other CPUs when migration_call(CPU_DEAD, ...) is
called so we may get a race between try_to_wake_up() and
migrate_live_tasks() -> move_task_off_dead_cpu(). The former one may push
a task out of a dead CPU causing the later one to loop endlessly.
Heiko Carstens observed:
| That's exactly what explains a dump I got yesterday. Thanks for fixing! :)
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Cc: miaox@cn.fujitsu.com
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Avi Kivity <avi@qumranet.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Remove the dubious attempt to prefer 'compute' over 'read'. Not only is it
wrong given commit c337869d (md: do not compute parity unless it is on a failed
drive), but it can trigger a BUG_ON in handle_parity_checks5().
Cc: <stable@kernel.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Neil Brown <neilb@suse.de>
Fix a range check in netfilter IP NAT for SNMP to always use a big enough size
variable that the compiler won't moan about comparing it to ULONG_MAX/8 on a
64-bit platform.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
When a conntrack entry is destroyed in process context and destruction
is interrupted by packet processing and the packet is an attempt to
reopen a closed connection, TCP conntrack tries to kill the old entry
itself and returns NF_REPEAT to pass the packet through the hook
again. This may lead to an endless loop: TCP conntrack repeatedly
finds the old entry, but can not kill it itself since destruction
is already in progress, but destruction in process context can not
complete since TCP conntrack is keeping the CPU busy.
Drop the packet in TCP conntrack if we can't kill the connection
ourselves to avoid this.
Reported by: hemao77@gmail.com [ Kernel bugzilla #11058 ]
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Milton Miller
Stephen Hemminger
J. Bruce Fields
Dmitry Adamushko
Hugh Dickins
Linus Torvalds
Nick Piggin
Steven Rostedt
Daniel Guilak
Mark Fasheh
Herbert Xu
Venkatesh Pallipadi
Dan Williams
David S. Miller
David Howells
Patrick McHardy
Ihar Hrachyshka