Rik van Riel 2084140594 mm: fix TLB flush race between migration, and change_protection_range ... There are a few subtle races, between change_protection_range (used by mprotect and change_prot_numa) on one side, and NUMA page migration and compaction on the other side. The basic race is that there is a time window between when the PTE gets made non-present (PROT_NONE or NUMA), and the TLB is flushed. During that time, a CPU may continue writing to the page. This is fine most of the time, however compaction or the NUMA migration code may come in, and migrate the page away. When that happens, the CPU may continue writing, through the cached translation, to what is no longer the current memory location of the process. This only affects x86, which has a somewhat optimistic pte_accessible. All other architectures appear to be safe, and will either always flush, or flush whenever there is a valid mapping, even with no permissions (SPARC). The basic race looks like this: CPU A CPU B CPU C load TLB entry make entry PTE/PMD_NUMA fault on entry read/write old page start migrating page change PTE/PMD to new page read/write old page [*] flush TLB reload TLB from new entry read/write new page lose data [*] the old page may belong to a new user at this point! The obvious fix is to flush remote TLB entries, by making sure that pte_accessible aware of the fact that PROT_NONE and PROT_NUMA memory may still be accessible if there is a TLB flush pending for the mm. This should fix both NUMA migration and compaction. [mgorman@suse.de: fix build] Signed-off-by: Rik van Riel <riel@redhat.com> Signed-off-by: Mel Gorman <mgorman@suse.de> Cc: Alex Thorlton <athorlton@sgi.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2013-12-18 19:04:51 -08:00
..
cpu	sched: Add NEED_RESCHED to the preempt_count	2013-09-25 14:07:49 +02:00
debug	kdb: Add support for external NMI handler to call KGDB/KDB	2013-10-03 18:47:54 +02:00
events	perf: Remove fragile swevent hlist optimization	2013-11-19 16:57:42 +01:00
gcov	gcov: reuse kbasename helper	2013-11-13 12:09:34 +09:00
irq	Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2013-12-02 10:15:39 -08:00
locking	locking/lockdep: Mark __lockdep_count_forward_deps() as static	2013-11-13 13:50:17 +01:00
power	Merge branch 'pm-sleep'	2013-11-19 01:07:08 +01:00
printk	printk.c: comments should refer to /proc/vmcore instead of /proc/vmcoreinfo	2013-11-13 12:09:14 +09:00
rcu	NOHZ: Check for nohz active instead of nohz enabled	2013-11-19 14:59:50 +01:00
sched	sched: numa: skip inaccessible VMAs	2013-12-18 19:04:51 -08:00
time	nohz: Fix another inconsistency between CONFIG_NO_HZ=n and nohz=off	2013-11-29 12:23:03 +01:00
trace	A regression showed up that there's a large delay when enabling	2013-12-06 08:34:16 -08:00
.gitignore	Ignore generated file kernel/x509_certificate_list	2013-12-10 18:21:34 +00:00
acct.c
async.c
audit_tree.c	kernel/audit_tree.c:audit_add_tree_rule(): protect `rule' from kill_rules()	2013-06-12 16:29:46 -07:00
audit_watch.c
audit.c	Merge git://git.infradead.org/users/eparis/audit	2013-11-21 19:18:14 -08:00
audit.h	audit: call audit_bprm() only once to add AUDIT_EXECVE information	2013-11-05 11:15:03 -05:00
auditfilter.c	audit: do not reject all AUDIT_INODE filter types	2013-11-05 11:09:16 -05:00
auditsc.c	audit: fix type of sessionid in audit_set_loginuid()	2013-11-06 11:47:24 -05:00
backtracetest.c
bounds.c	kernel/bounds: avoid circular dependencies in generated headers	2013-11-19 14:20:12 -08:00
capability.c	xfs: update for v3.12-rc1	2013-09-09 11:19:09 -07:00
cgroup_freezer.c	cgroup: make css_for_each_descendant() and friends include the origin css in the iteration	2013-08-08 20:11:27 -04:00
cgroup.c	cgroup: fix cgroup_subsys_state leak for seq_files	2013-11-27 18:16:21 -05:00
compat.c
configs.c
context_tracking.c	Linux 3.12-rc4	2013-10-09 12:36:13 +02:00
cpu_pm.c
cpu.c	Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2013-11-14 16:55:11 +09:00
cpuset.c	cpuset: Fix memory allocator deadlock	2013-11-27 13:52:47 -05:00
crash_dump.c
cred.c
delayacct.c	kernel/delayacct.c: remove redundant checking in __delayacct_add_tsk()	2013-11-13 12:09:12 +09:00
dma.c
elfcore.c	switch elf_core_write_extra_phdrs() to dump_emit()	2013-11-09 00:16:23 -05:00
exec_domain.c
exit.c	ptrace: revert "Prepare to fix racy accesses on task breakpoints"	2013-07-09 10:33:26 -07:00
extable.c	kernel/extable: fix address-checks for core_kernel and init areas	2013-11-28 09:49:41 -08:00
fork.c	mm: fix TLB flush race between migration, and change_protection_range	2013-12-18 19:04:51 -08:00
freezer.c	freezer: set PF_SUSPEND_TASK flag on tasks that call freeze_processes	2013-07-30 14:05:06 +02:00
futex_compat.c
futex.c	futex: move user address verification up to common code	2013-12-12 09:53:51 -08:00
groups.c	userns: Kill nsown_capable it makes the wrong thing easy	2013-08-30 23:44:11 -07:00
hrtimer.c	kernel: delete __cpuinit usage from all core kernel files	2013-07-14 19:36:59 -04:00
hung_task.c	Here are the 3.13 KVM changes. There was a lot of work on the PPC	2013-11-15 13:51:36 +09:00
irq_work.c
itimer.c
jump_label.c	static_key: WARN on usage before jump_label_init was called	2013-10-19 19:45:35 -04:00
kallsyms.c
kcmp.c
Kconfig.freezer
Kconfig.hz	kernel: remove CONFIG_USE_GENERIC_SMP_HELPERS	2013-11-15 09:32:22 +09:00
Kconfig.locks	locking: Fix copy/paste errors of "ARCH_INLINE_*_UNLOCK_BH"	2013-05-28 08:50:00 +02:00
Kconfig.preempt
kexec.c	kexec: migrate to reboot cpu	2013-12-18 19:04:50 -08:00
kmod.c	kernel/kmod.c: check for NULL in call_usermodehelper_exec()	2013-09-30 14:31:02 -07:00
kprobes.c	kprobes: use KSYM_NAME_LEN to size identifier buffers	2013-11-13 12:09:26 +09:00
ksysfs.c	kernel: replace strict_strto*() with kstrto*()	2013-09-12 15:38:03 -07:00
kthread.c	kthread: make kthread_create() killable	2013-11-13 12:08:59 +09:00
latencytop.c
Makefile	Merge branch 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security	2013-11-21 19:46:00 -08:00
module_signing.c	keys: change asymmetric keys to use common hash definitions	2013-10-25 17:15:18 -04:00
module-internal.h	KEYS: Separate the kernel signature checking keyring from module signing	2013-09-25 17:17:01 +01:00
module.c	Mainly boring here, too. rmmod --wait finally removed, though.	2013-11-15 13:27:50 +09:00
notifier.c
nsproxy.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace	2013-09-07 14:35:32 -07:00
padata.c	padata: make the sequence counter an atomic_t	2013-10-30 12:02:58 +08:00
panic.c	kernel/panic.c: reduce 1 byte usage for print tainted buffer	2013-11-13 12:09:35 +09:00
params.c	kernel/params: fix handling of signed integer types	2013-09-28 12:35:52 -07:00
pid_namespace.c	pid_namespace: make freeing struct pid_namespace rcu-delayed	2013-10-24 23:43:29 -04:00
pid.c	pidns: fix free_pid() to handle the first fork failure	2013-09-30 14:31:03 -07:00
posix-cpu-timers.c	posix_timers: fix racy timer delta caching on task exit	2013-07-03 16:54:42 +02:00
posix-timers.c
profile.c	kernel: delete __cpuinit usage from all core kernel files	2013-07-14 19:36:59 -04:00
ptrace.c	exec/ptrace: fix get_dumpable() incorrect tests	2013-11-13 12:09:33 +09:00
range.c	range: Do not add new blank slot with add_range_with_merge	2013-06-18 11:32:10 -05:00
reboot.c	kexec: migrate to reboot cpu	2013-12-18 19:04:50 -08:00
relay.c	kernel: delete __cpuinit usage from all core kernel files	2013-07-14 19:36:59 -04:00
res_counter.c	memcg: reduce function dereference	2013-09-12 15:38:02 -07:00
resource.c	kernel/resource.c: remove the unneeded assignment in function __find_resource	2013-07-03 16:08:06 -07:00
seccomp.c
signal.c	constify copy_siginfo_to_user{,32}()	2013-11-09 00:16:29 -05:00
smp.c	kernel: fix generic_exec_single indentation	2013-11-15 09:32:22 +09:00
smpboot.c	kernel: delete __cpuinit usage from all core kernel files	2013-07-14 19:36:59 -04:00
smpboot.h
softirq.c	revert "softirq: Add support for triggering softirq work on softirqs"	2013-11-15 09:32:22 +09:00
stacktrace.c
stop_machine.c	stop_machine: Fix race between stop_two_cpus() and stop_cpus()	2013-11-11 12:43:38 +01:00
sys_ni.c
sys.c	kernel/sys.c: remove obsolete #include <linux/kexec.h>	2013-11-13 12:09:13 +09:00
sysctl_binary.c	kernel/sysctl_binary.c: use scnprintf() instead of snprintf()	2013-11-13 12:09:33 +09:00
sysctl.c	Merge branch 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2013-11-14 16:30:30 +09:00
system_certificates.S	KEYS: correct alignment of system_certificate_list content in assembly file	2013-12-10 18:25:28 +00:00
system_keyring.c	KEYS: correct alignment of system_certificate_list content in assembly file	2013-12-10 18:25:28 +00:00
task_work.c	task_work: documentation	2013-09-11 15:58:27 -07:00
taskstats.c	genetlink: only pass array to genl_register_family_with_ops()	2013-11-19 16:39:05 -05:00
test_kprobes.c
time.c	sched: Rename sched.c as sched/core.c in comments and Documentation	2013-06-19 12:58:42 +02:00
timeconst.bc
timer.c	timer: Convert kmalloc_node(...GFP_ZERO...) to kzalloc_node(...)	2013-11-19 14:59:50 +01:00
tracepoint.c
tsacct.c
uid16.c	userns: Kill nsown_capable it makes the wrong thing easy	2013-08-30 23:44:11 -07:00
up.c	kernel: provide a __smp_call_function_single stub for !CONFIG_SMP	2013-11-15 09:32:22 +09:00
user_namespace.c	KEYS: Add per-user_namespace registers for persistent per-UID kerberos caches	2013-09-24 10:35:19 +01:00
user-return-notifier.c
user.c	KEYS: Add per-user_namespace registers for persistent per-UID kerberos caches	2013-09-24 10:35:19 +01:00
utsname_sysctl.c
utsname.c	userns: Kill nsown_capable it makes the wrong thing easy	2013-08-30 23:44:11 -07:00
watchdog.c	watchdog: update watchdog_thresh properly	2013-09-24 17:00:25 -07:00
workqueue_internal.h	sched: Rename sched.c as sched/core.c in comments and Documentation	2013-06-19 12:58:42 +02:00
workqueue.c	PCI updates for v3.13:	2013-12-15 11:45:27 -08:00