Oleg Nesterov [Tue, 26 Mar 2013 23:24:03 +0000 (10:24 +1100)]
kthread: kill task_get_live_kthread()
task_get_live_kthread() looks confusing and unneeded. It does
get_task_struct() but only kthread_stop() needs this, it can be called
even if the calller doesn't have a reference when we know that this
kthread can't exit until we do kthread_stop().
kthread_park() and kthread_unpark() do not need get_task_struct(), the
callers already have the reference. And it can not help if we can race
with the exiting kthread anyway, kthread_park() can hang forever in this
case.
Change kthread_park() and kthread_unpark() to use to_live_kthread(),
change kthread_stop() to do get_task_struct() by hand and remove
task_get_live_kthread().
Signed-off-by: Oleg Nesterov <oleg@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Namhyung Kim <namhyung@kernel.org> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Oleg Nesterov [Tue, 26 Mar 2013 23:24:03 +0000 (10:24 +1100)]
kthread: introduce to_live_kthread()
"k->vfork_done != NULL" with a barrier() after to_kthread(k) in
task_get_live_kthread(k) looks unclear, and sub-optimal because we load
->vfork_done twice.
All we need is to ensure that we do not return to_kthread(NULL). Add a
new trivial helper which loads/checks ->vfork_done once, this also looks
more understandable.
Signed-off-by: Oleg Nesterov <oleg@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Namhyung Kim <namhyung@kernel.org> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Jarod Wilson [Tue, 26 Mar 2013 23:24:03 +0000 (10:24 +1100)]
drivers/char/random.c: fix priming of last_data
Commit ec8f02da9e ("random: prime last_data value per fips requirements")
added priming of last_data per fips requirements. Unfortuantely, it did
so in a way that can lead to multiple threads all incrementing nbytes, but
only one actually doing anything with the extra data, which leads to some
fun random corruption and panics.
The fix is to simply do everything needed to prime last_data in a single
shot, so there's no window for multiple cpus to increment nbytes -- in
fact, we won't even increment or decrement nbytes anymore, we'll just
extract the needed EXTRACT_SIZE one time per pool and then carry on with
the normal routine.
All these changes have been tested across multiple hosts and architectures
where panics were previously encoutered. The code changes are are
strictly limited to areas only touched when when booted in fips mode.
This change should also go into 3.8-stable, to make the myriads of fips
users on 3.8.x happy.
Signed-off-by: Jarod Wilson <jarod@redhat.com> Tested-by: Jan Stancek <jstancek@redhat.com> Tested-by: Jan Stodola <jstodola@redhat.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Acked-by: Neil Horman <nhorman@tuxdriver.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Matt Mackall <mpm@selenic.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Sanjay Lal [Tue, 26 Mar 2013 23:24:02 +0000 (10:24 +1100)]
mips: define KVM_USER_MEM_SLOTS
ARCH=mips, config=fuloong2e_defconfig:
akpm3:/usr/src/25> make arch/mips/kernel/early_printk.o
...
CC arch/mips/kernel/asm-offsets.s
In file included from arch/mips/kernel/asm-offsets.c:20:
include/linux/kvm_host.h:334: error: `KVM_USER_MEM_SLOTS' undeclared here (not in a function)
Signed-off-by: Sanjay Lal <sanjayl@kymasys.com> Reported-by: Andrew Morton <akpm@linux-foundation.org> Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Gleb Natapov <gleb@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Oleg Nesterov [Tue, 26 Mar 2013 23:24:02 +0000 (10:24 +1100)]
thinkpad-acpi: kill hotkey_thread_mutex
hotkey_kthread() does try_to_freeze() under hotkey_thread_mutex.
We can simply kill this mutex, hotkey_poll_stop_sync() does not need to
serialize with hotkey_kthread(). When kthread_stop() returns the thread
is already dead, it called do_exit()->complete_vfork_done().
Reported-by: Artem Savkov <artem.savkov@gmail.com> Reported-by: Maciej Rutecki <maciej.rutecki@gmail.com> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br> Cc: Matthew Garrett <matthew.garrett@nebula.com> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Reviewed-by: Mandeep Singh Baines <msb@chromium.org> Cc: Aaron Lu <aaron.lu@intel.com> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Andrew Morton [Tue, 26 Mar 2013 23:24:02 +0000 (10:24 +1100)]
revert "ipc: don't allocate a copy larger than max"
Revert 88b9e456b164. Dave has confirmed that this was causing oopses
during trinity testing.
Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Stanislav Kinsbursky <skinsbursky@parallels.com> Reported-by: Dave Jones <davej@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
K. Y. Srinivasan [Tue, 26 Mar 2013 23:24:01 +0000 (10:24 +1100)]
mm: export split_page()
This symbol will be used in the Hyper-V balloon driver to support 2M
allocations.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Acked-by: Michal Hocko <mhocko@suse.cz> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
projects / karo-tx-linux.git / log