kernel_optimize_test/kernel
Kirill A. Shutemov c8394812e5 uprobes: split THPs before trying to replace them
Patch series "Fix few rmap-related THP bugs", v3.

The patchset fixes handing PTE-mapped THPs in page_referenced() and
page_idle_clear_pte_refs().

To achieve that I've intrdocued new helper -- page_vma_mapped_walk() --
which replaces all page_check_address{,_transhuge}() and covers all THP
cases.

Patchset overview:
  - First patch fixes one uprobe bug (unrelated to the rest of the
    patchset, just spotted it at the same time);

  - Patches 2-5 fix handling PTE-mapped THPs in page_referenced(),
    page_idle_clear_pte_refs() and rmap core;

  - Patches 6-12 convert all page_check_address{,_transhuge}() users
    (plus remove_migration_pte()) to page_vma_mapped_walk() and drop
    unused helpers.

I think the fixes are not critical enough for stable@ as they don't lead
to crashes or hangs, only suboptimal behaviour.

This patch (of 12):

For THPs page_check_address() always fails.  It leads to endless loop in
uprobe_write_opcode().

Testcase with huge-tmpfs (uprobes cannot probe anonymous memory).

	mount -t debugfs none /sys/kernel/debug
	mount -t tmpfs -o huge=always none /mnt
	gcc -Wall -O2 -o /mnt/test -x c - <<EOF
	int main(void)
	{
		return 0;
	}
	/* Padding to map the code segment with huge pmd */
	asm (".zero 2097152");
	EOF
	echo 'p /mnt/test:0' > /sys/kernel/debug/tracing/uprobe_events
	echo 1 > /sys/kernel/debug/tracing/events/uprobes/enable
	/mnt/test

Let's split THPs before trying to replace.

Link: http://lkml.kernel.org/r/20170129173858.45174-2-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Rik van Riel <riel@redhat.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-24 17:46:55 -08:00
..
bpf bpf: fix spelling mistake: "proccessed" -> "processed" 2017-02-23 10:46:08 -05:00
configs
debug
events uprobes: split THPs before trying to replace them 2017-02-24 17:46:55 -08:00
gcov
irq IOMMU Updates for Linux v4.11 2017-02-20 16:42:43 -08:00
livepatch
locking Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-02-20 13:23:30 -08:00
power This renames the (now inaccurate) CONFIG_DEBUG_RODATA and related config 2017-02-21 17:56:45 -08:00
printk Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk 2017-02-22 17:33:34 -08:00
rcu
sched sched/core: Fix build paravirt build on arm and arm64 2017-02-21 10:54:02 -08:00
time
trace Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2017-02-23 20:33:51 -08:00
.gitignore
acct.c
async.c
audit_fsnotify.c
audit_tree.c
audit_watch.c
audit.c Merge branch 'stable-4.11' of git://git.infradead.org/users/pcmoore/audit 2017-02-21 13:25:50 -08:00
audit.h Merge branch 'stable-4.11' of git://git.infradead.org/users/pcmoore/audit 2017-02-21 13:25:50 -08:00
auditfilter.c
auditsc.c Merge branch 'stable-4.11' of git://git.infradead.org/users/pcmoore/audit 2017-02-21 13:25:50 -08:00
backtracetest.c
bounds.c
capability.c
cgroup_freezer.c
cgroup_pids.c
cgroup.c
compat.c
configs.c
context_tracking.c
cpu_pm.c
cpu.c
cpuset.c
crash_dump.c
cred.c
delayacct.c
dma.c
elfcore.c
exec_domain.c
exit.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2017-02-23 20:33:51 -08:00
extable.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2017-02-22 10:15:09 -08:00
fork.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2017-02-23 20:33:51 -08:00
freezer.c
futex_compat.c
futex.c
groups.c
hung_task.c
irq_work.c
jump_label.c
kallsyms.c
kcmp.c
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
kcov.c
kexec_core.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk 2017-02-22 17:33:34 -08:00
kexec_file.c
kexec_internal.h
kexec.c
kmod.c
kprobes.c powerpc updates for 4.11 part 1. 2017-02-22 10:30:38 -08:00
ksysfs.c
kthread.c
latencytop.c
Makefile
membarrier.c
memremap.c mm, devm_memremap_pages: hold device_hotplug lock over mem_hotplug_{begin, done} 2017-02-24 17:46:53 -08:00
module_signing.c
module-internal.h
module.c Modules updates for v4.11 2017-02-22 17:08:33 -08:00
notifier.c
nsproxy.c
padata.c
panic.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk 2017-02-22 17:33:34 -08:00
params.c
pid_namespace.c
pid.c
profile.c
ptrace.c
range.c
reboot.c
relay.c mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmf 2017-02-24 17:46:54 -08:00
resource.c
seccomp.c seccomp: Only dump core when single-threaded 2017-02-23 09:42:35 +11:00
signal.c
smp.c
smpboot.c
smpboot.h
softirq.c
stacktrace.c
stop_machine.c
sys_ni.c
sys.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2017-02-23 20:33:51 -08:00
sysctl_binary.c
sysctl.c
task_work.c
taskstats.c
test_kprobes.c
torture.c
tracepoint.c
tsacct.c
ucount.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2017-02-23 20:33:51 -08:00
uid16.c
up.c
user_namespace.c
user-return-notifier.c
user.c
utsname_sysctl.c
utsname.c
watchdog_hld.c kernel/watchdog.c: do not hardcode CPU 0 as the initial thread 2017-02-22 16:41:27 -08:00
watchdog.c
workqueue_internal.h
workqueue.c