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.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
audit_tree.c
audit_watch.c
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.c
cgroup: fix cgroup_subsys_state leak for seq_files
2013-11-27 18:16:21 -05:00
cgroup_freezer.c
compat.c
configs.c
context_tracking.c
Linux 3.12-rc4
2013-10-09 12:36:13 +02:00
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
cpu_pm.c
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
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
futex.c
futex: move user address verification up to common code
2013-12-12 09:53:51 -08:00
futex_compat.c
groups.c
hrtimer.c
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
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-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
module_signing.c
keys: change asymmetric keys to use common hash definitions
2013-10-25 17:15:18 -04:00
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.c
pidns: fix free_pid() to handle the first fork failure
2013-09-30 14:31:03 -07:00
pid_namespace.c
pid_namespace: make freeing struct pid_namespace rcu-delayed
2013-10-24 23:43:29 -04:00
posix-cpu-timers.c
posix-timers.c
profile.c
ptrace.c
exec/ptrace: fix get_dumpable() incorrect tests
2013-11-13 12:09:33 +09:00
range.c
reboot.c
kexec: migrate to reboot cpu
2013-12-18 19:04:50 -08:00
relay.c
res_counter.c
memcg: reduce function dereference
2013-09-12 15:38:02 -07:00
resource.c
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
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.c
kernel/sys.c: remove obsolete #include <linux/kexec.h>
2013-11-13 12:09:13 +09:00
sys_ni.c
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
sysctl_binary.c
kernel/sysctl_binary.c: use scnprintf() instead of snprintf()
2013-11-13 12:09:33 +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
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
up.c
kernel: provide a __smp_call_function_single stub for !CONFIG_SMP
2013-11-15 09:32:22 +09:00
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
user_namespace.c
KEYS: Add per-user_namespace registers for persistent per-UID kerberos caches
2013-09-24 10:35:19 +01:00
utsname.c
utsname_sysctl.c
watchdog.c
watchdog: update watchdog_thresh properly
2013-09-24 17:00:25 -07:00
workqueue.c
PCI updates for v3.13:
2013-12-15 11:45:27 -08:00
workqueue_internal.h