Chaning cpuset->mems/cpuset->cpus should be protected under
callback_mutex.
cpuset_clone() doesn't follow this rule. It's ok because it's
called when creating and initializing a cgroup, but we'd better
hold the lock to avoid subtil break in the future.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Paul Menage <menage@google.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Those functions that use NODEMASK_ALLOC() can't propagate errno
to users, but will fail silently.
Fix it by using a static nodemask_t variable for each function, and
those variables are protected by cgroup_mutex;
[akpm@linux-foundation.org: fix comment spelling, strengthen cgroup_lock comment]
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Paul Menage <menage@google.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It's not necessary to copy cpuset->mems_allowed to a buffer allocated by
NODEMASK_ALLOC(). Just pass it to nodelist_scnprintf().
As spotted by Paul, a side effect is we fix a bug that the function can
return -ENOMEM but the caller doesn't expect negative return value.
Therefore change the return value of cpuset_sprintf_cpulist() and
cpuset_sprintf_memlist() from int to size_t.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Paul Menage <menage@google.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We've been burned by regressions/bugs which we later realized could have
been triaged quicker if only we'd paid closer attention to dmesg. To make
it easier to audit dmesg, we'd like to make DEFAULT_MESSAGE_LEVEL
Kconfig-settable. That way we can set it to KERN_NOTICE and audit any
messages <= KERN_WARNING.
Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Joe Perches <joe@perches.com>
Cc: Olof Johansson <olofj@chromium.org>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In an effort to reduce kernel address leaks that might be used to help
target kernel privilege escalation exploits, this patch uses %pK when
displaying addresses in /proc/kallsyms, /proc/modules, and
/sys/module/*/sections/*.
Note that this changes %x to %p, so some legitimately 0 values in
/proc/kallsyms would have changed from 00000000 to "(null)". To avoid
this, "(null)" is not used when using the "K" format. Anything that was
already successfully parsing "(null)" in addition to full hex digits
should have no problem with this change. (Thanks to Joe Perches for the
suggestion.) Due to the %x to %p, "void *" casts are needed since these
addresses are already "unsigned long" everywhere internally, due to their
starting life as ELF section offsets.
Signed-off-by: Kees Cook <kees.cook@canonical.com>
Cc: Eugene Teo <eugene@redhat.com>
Cc: Dan Rosenberg <drosenberg@vsecurity.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For a platform with many consoles like:
"console=tty1 console=ttyMFD2 console=ttyS0 earlyprintk=mrst"
Each time when the non "selected_console" (tty1 and ttyMFD2 here) get
registered, the existing kernel message will be printed out on registered
consoles again, the "mrst" early console will get some same message for 3
times, and "tty1" will get some for twice.
As suggested by Andrew Morton, every time a new console is registered, it
will be set as the "exclusive" console which will dump the already
existing kernel messages.
Signed-off-by: Feng Tang <feng.tang@intel.com>
Cc: Greg KH <gregkh@suse.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On some architectures, the boot process involves de-registering the boot
console (early boot), initialize drivers and then re-register the console.
This mechanism introduces a window in which no printk can happen on the
console and messages are buffered and then printed once the new console is
available.
If a kernel crashes during this window, all it's left on the boot console
is "console [foo] enabled, bootconsole disabled" making debug of the crash
rather 'interesting'.
By adding "keep_bootcon" option, do not unregister the boot console, that
will allow to printk everything that is happening up to the crash.
The option is clearly meant only for debugging purposes as it introduces
lots of duplicated info printed on console, but will make bug report from
users easier as it doesn't require a kernel build just to figure out where
we crash.
Signed-off-by: Fabio M. Di Nitto <fabbione@fabbione.net>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Greg KH <gregkh@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch addresses a couple of problems. One was the case when the
hardlockup failed to start, it also failed to start the softlockup. There
were valid cases when the hardlockup shouldn't start and that shouldn't
block the softlockup (no lapic, bios controls perf counters).
The second problem was when the hardlockup failed to start on boxes (from
a no lapic or bios controlled perf counter case), it reported failure to
the cpu notifier chain. This blocked the notifier from continuing to
start other more critical pieces of cpu bring-up (in our case based on a
2.6.32 fork, it was the mce). As a result, during soft cpu online/offline
testing, the system would panic when a cpu was offlined because the cpu
notifier would succeed in processing a watchdog disable cpu event and
would panic in the mce case as a result of un-initialized variables from a
never executed cpu up event.
I realized the hardlockup/softlockup cases are really just debugging aids
and should never impede the progress of a cpu up/down event. Therefore I
modified the code to always return NOTIFY_OK and instead rely on printks
to inform the user of problems.
Signed-off-by: Don Zickus <dzickus@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When a cpu is considered stuck, instead of limping along and just printing
a warning, it is sometimes preferred to just panic, let kdump capture the
vmcore and reboot. This gets the machine back into a stable state quickly
while saving the info that got it into a stuck state to begin with.
Add a Kconfig option to allow users to set the hardlockup to panic
by default. Also add in a 'nmi_watchdog=nopanic' to override this.
[akpm@linux-foundation.org: fix strncmp length]
Signed-off-by: Don Zickus <dzickus@redhat.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: WANG Cong <xiyou.wangcong@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cleanup: kill the dead code which does nothing but complicates the code
and confuses the reader.
sys_unshare(CLONE_THREAD/SIGHAND/VM) is not really implemented, and I
doubt very much it will ever work. At least, nobody even tried since the
original 99d1419d96 ("unshare system call -v5: system call
handler function") was applied more than 4 years ago.
And the code is not consistent. unshare_thread() always fails
unconditionally, while unshare_sighand() and unshare_vm() pretend to work
if there is nothing to unshare.
Remove unshare_thread(), unshare_sighand(), unshare_vm() helpers and
related variables and add a simple CLONE_THREAD | CLONE_SIGHAND| CLONE_VM
check into check_unshare_flags().
Also, move the "CLONE_NEWNS needs CLONE_FS" check from
check_unshare_flags() to sys_unshare(). This looks more consistent and
matches the similar do_sysvsem check in sys_unshare().
Note: with or without this patch "atomic_read(mm->mm_users) > 1" can give
a false positive due to get_task_mm().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Roland McGrath <roland@redhat.com>
Cc: Janak Desai <janak@us.ibm.com>
Cc: Daniel Lezcano <daniel.lezcano@free.fr>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Change the printk() calls to have the KERN_INFO/KERN_ERROR stuff, and
fixes other coding style errors. Not _all_ of them are gone, though.
[akpm@linux-foundation.org: revert the bits I disagree with]
Signed-off-by: Michael Rodriguez <dkingston02@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
All kthreads being created from a single helper task, they all use memory
from a single node for their kernel stack and task struct.
This patch suite creates kthread_create_on_cpu(), adding a 'cpu' parameter
to parameters already used by kthread_create().
This parameter serves in allocating memory for the new kthread on its
memory node if available.
Users of this new function are : ksoftirqd, kworker, migration, pktgend...
This patch:
Add a node parameter to alloc_task_struct(), and change its name to
alloc_task_struct_node()
This change is needed to allow NUMA aware kthread_create_on_cpu()
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: David S. Miller <davem@davemloft.net>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Tejun Heo <tj@kernel.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: David Howells <dhowells@redhat.com>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
list_del() leaves poison in the prev and next pointers. The next
list_empty() will compare those poisons, and say the list isn't empty.
Any list operations that assume the node is on a list because of such a
check will be fooled into dereferencing poison. One needs to INIT the
node after the del, and fortunately there's already a wrapper for that -
list_del_init().
Some of the dels are followed by deallocations, so can be ignored, and one
can be merged with an add to make a move. Apart from that, I erred on the
side of caution in making nodes list_empty()-queriable.
Signed-off-by: Phil Carmody <ext-phil.2.carmody@nokia.com>
Reviewed-by: Paul Menage <menage@google.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Kirill A. Shutemov <kirill@shutemov.name>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Userland should be able to trust the pid and uid of the sender of a
signal if the si_code is SI_TKILL.
Unfortunately, the kernel has historically allowed sigqueueinfo() to
send any si_code at all (as long as it was negative - to distinguish it
from kernel-generated signals like SIGILL etc), so it could spoof a
SI_TKILL with incorrect siginfo values.
Happily, it looks like glibc has always set si_code to the appropriate
SI_QUEUE, so there are probably no actual user code that ever uses
anything but the appropriate SI_QUEUE flag.
So just tighten the check for si_code (we used to allow any negative
value), and add a (one-time) warning in case there are binaries out
there that might depend on using other si_code values.
Signed-off-by: Julien Tinnes <jln@google.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'trivial' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild-2.6: (25 commits)
video: change to new flag variable
scsi: change to new flag variable
rtc: change to new flag variable
rapidio: change to new flag variable
pps: change to new flag variable
net: change to new flag variable
misc: change to new flag variable
message: change to new flag variable
memstick: change to new flag variable
isdn: change to new flag variable
ieee802154: change to new flag variable
ide: change to new flag variable
hwmon: change to new flag variable
dma: change to new flag variable
char: change to new flag variable
fs: change to new flag variable
xtensa: change to new flag variable
um: change to new flag variables
s390: change to new flag variable
mips: change to new flag variable
...
Fix up trivial conflict in drivers/hwmon/Makefile
* 'irq-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
genirq: Fix incorrect unlock in __setup_irq()
cris: Use generic show_interrupts()
genirq: show_interrupts: Check desc->name before printing it blindly
cris: Use accessor functions to set IRQ_PER_CPU flag
cris: Fix irq conversion fallout
* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
sched, kernel-doc: Fix runqueue_is_locked() description
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (30 commits)
trace, filters: Initialize the match variable in process_ops() properly
trace, documentation: Fix branch profiling location in debugfs
oprofile, s390: Cleanups
oprofile, s390: Remove hwsampler_files.c and merge it into init.c
perf: Fix tear-down of inherited group events
perf: Reorder & optimize perf_event_context to remove alignment padding on 64 bit builds
perf: Handle stopped state with tracepoints
perf: Fix the software events state check
perf, powerpc: Handle events that raise an exception without overflowing
perf, x86: Use INTEL_*_CONSTRAINT() for all PEBS event constraints
perf, x86: Clean up SandyBridge PEBS events
perf lock: Fix sorting by wait_min
perf tools: Version incorrect with some versions of grep
perf evlist: New command to list the names of events present in a perf.data file
perf script: Add support for H/W and S/W events
perf script: Add support for dumping symbols
perf script: Support custom field selection for output
perf script: Move printing of 'common' data from print_event and rename
perf tracing: Remove print_graph_cpu and print_graph_proc from trace-event-parse
perf script: Change process_event prototype
...
