Merge branch 'akpm' (patches from Andrew)
Merge misc fixes from Andrew Morton:
"24 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (24 commits)
autofs: fix error return in autofs_fill_super()
autofs: drop dentry reference only when it is never used
fs/drop_caches.c: avoid softlockups in drop_pagecache_sb()
mm: migrate: don't rely on __PageMovable() of newpage after unlocking it
psi: clarify the Kconfig text for the default-disable option
mm, memory_hotplug: __offline_pages fix wrong locking
mm: hwpoison: use do_send_sig_info() instead of force_sig()
kasan: mark file common so ftrace doesn't trace it
init/Kconfig: fix grammar by moving a closing parenthesis
lib/test_kmod.c: potential double free in error handling
mm, oom: fix use-after-free in oom_kill_process
mm/hotplug: invalid PFNs from pfn_to_online_page()
mm,memory_hotplug: fix scan_movable_pages() for gigantic hugepages
psi: fix aggregation idle shut-off
mm, memory_hotplug: test_pages_in_a_zone do not pass the end of zone
mm, memory_hotplug: is_mem_section_removable do not pass the end of a zone
oom, oom_reaper: do not enqueue same task twice
mm: migrate: make buffer_migrate_page_norefs() actually succeed
kernel/exit.c: release ptraced tasks before zap_pid_ns_processes
x86_64: increase stack size for KASAN_EXTRA
...
diff --git a/arch/c6x/include/asm/Kbuild b/arch/c6x/include/asm/Kbuild
index 33a2c94..63b4a17 100644
--- a/arch/c6x/include/asm/Kbuild
+++ b/arch/c6x/include/asm/Kbuild
@@ -30,6 +30,7 @@
generic-y += preempt.h
generic-y += segment.h
generic-y += serial.h
+generic-y += shmparam.h
generic-y += tlbflush.h
generic-y += topology.h
generic-y += trace_clock.h
diff --git a/arch/c6x/include/uapi/asm/Kbuild b/arch/c6x/include/uapi/asm/Kbuild
index 6c6f630..0febf1a 100644
--- a/arch/c6x/include/uapi/asm/Kbuild
+++ b/arch/c6x/include/uapi/asm/Kbuild
@@ -1,5 +1,4 @@
include include/uapi/asm-generic/Kbuild.asm
generic-y += kvm_para.h
-generic-y += shmparam.h
generic-y += ucontext.h
diff --git a/arch/h8300/include/asm/Kbuild b/arch/h8300/include/asm/Kbuild
index cd400d3..961c1dc 100644
--- a/arch/h8300/include/asm/Kbuild
+++ b/arch/h8300/include/asm/Kbuild
@@ -40,6 +40,7 @@
generic-y += scatterlist.h
generic-y += sections.h
generic-y += serial.h
+generic-y += shmparam.h
generic-y += sizes.h
generic-y += spinlock.h
generic-y += timex.h
diff --git a/arch/h8300/include/uapi/asm/Kbuild b/arch/h8300/include/uapi/asm/Kbuild
index 6c6f630..0febf1a 100644
--- a/arch/h8300/include/uapi/asm/Kbuild
+++ b/arch/h8300/include/uapi/asm/Kbuild
@@ -1,5 +1,4 @@
include include/uapi/asm-generic/Kbuild.asm
generic-y += kvm_para.h
-generic-y += shmparam.h
generic-y += ucontext.h
diff --git a/arch/hexagon/include/asm/Kbuild b/arch/hexagon/include/asm/Kbuild
index 47c4da3..b25fd42 100644
--- a/arch/hexagon/include/asm/Kbuild
+++ b/arch/hexagon/include/asm/Kbuild
@@ -30,6 +30,7 @@
generic-y += sections.h
generic-y += segment.h
generic-y += serial.h
+generic-y += shmparam.h
generic-y += sizes.h
generic-y += topology.h
generic-y += trace_clock.h
diff --git a/arch/hexagon/include/uapi/asm/Kbuild b/arch/hexagon/include/uapi/asm/Kbuild
index 61d955c..c1b06dc 100644
--- a/arch/hexagon/include/uapi/asm/Kbuild
+++ b/arch/hexagon/include/uapi/asm/Kbuild
@@ -1,4 +1,3 @@
include include/uapi/asm-generic/Kbuild.asm
-generic-y += shmparam.h
generic-y += ucontext.h
diff --git a/arch/m68k/include/asm/Kbuild b/arch/m68k/include/asm/Kbuild
index 9f1dd26..95f8f63 100644
--- a/arch/m68k/include/asm/Kbuild
+++ b/arch/m68k/include/asm/Kbuild
@@ -20,6 +20,7 @@
generic-y += percpu.h
generic-y += preempt.h
generic-y += sections.h
+generic-y += shmparam.h
generic-y += spinlock.h
generic-y += topology.h
generic-y += trace_clock.h
diff --git a/arch/m68k/include/uapi/asm/Kbuild b/arch/m68k/include/uapi/asm/Kbuild
index b8b3525..960bf1e 100644
--- a/arch/m68k/include/uapi/asm/Kbuild
+++ b/arch/m68k/include/uapi/asm/Kbuild
@@ -2,4 +2,3 @@
generated-y += unistd_32.h
generic-y += kvm_para.h
-generic-y += shmparam.h
diff --git a/arch/microblaze/include/asm/Kbuild b/arch/microblaze/include/asm/Kbuild
index 9c7d1d2..791cc8d5 100644
--- a/arch/microblaze/include/asm/Kbuild
+++ b/arch/microblaze/include/asm/Kbuild
@@ -26,6 +26,7 @@
generic-y += percpu.h
generic-y += preempt.h
generic-y += serial.h
+generic-y += shmparam.h
generic-y += syscalls.h
generic-y += topology.h
generic-y += trace_clock.h
diff --git a/arch/microblaze/include/uapi/asm/Kbuild b/arch/microblaze/include/uapi/asm/Kbuild
index 28823e3..97823ec 100644
--- a/arch/microblaze/include/uapi/asm/Kbuild
+++ b/arch/microblaze/include/uapi/asm/Kbuild
@@ -2,5 +2,4 @@
generated-y += unistd_32.h
generic-y += kvm_para.h
-generic-y += shmparam.h
generic-y += ucontext.h
diff --git a/arch/openrisc/include/asm/Kbuild b/arch/openrisc/include/asm/Kbuild
index eb87cd8..1f04844b 100644
--- a/arch/openrisc/include/asm/Kbuild
+++ b/arch/openrisc/include/asm/Kbuild
@@ -34,6 +34,7 @@
generic-y += qrwlock.h
generic-y += sections.h
generic-y += segment.h
+generic-y += shmparam.h
generic-y += string.h
generic-y += switch_to.h
generic-y += topology.h
diff --git a/arch/openrisc/include/uapi/asm/Kbuild b/arch/openrisc/include/uapi/asm/Kbuild
index 6c6f630..0febf1a 100644
--- a/arch/openrisc/include/uapi/asm/Kbuild
+++ b/arch/openrisc/include/uapi/asm/Kbuild
@@ -1,5 +1,4 @@
include include/uapi/asm-generic/Kbuild.asm
generic-y += kvm_para.h
-generic-y += shmparam.h
generic-y += ucontext.h
diff --git a/arch/unicore32/include/asm/Kbuild b/arch/unicore32/include/asm/Kbuild
index 1372553..1d1544b 100644
--- a/arch/unicore32/include/asm/Kbuild
+++ b/arch/unicore32/include/asm/Kbuild
@@ -28,6 +28,7 @@
generic-y += sections.h
generic-y += segment.h
generic-y += serial.h
+generic-y += shmparam.h
generic-y += sizes.h
generic-y += syscalls.h
generic-y += topology.h
diff --git a/arch/unicore32/include/uapi/asm/Kbuild b/arch/unicore32/include/uapi/asm/Kbuild
index 6c6f630..0febf1a 100644
--- a/arch/unicore32/include/uapi/asm/Kbuild
+++ b/arch/unicore32/include/uapi/asm/Kbuild
@@ -1,5 +1,4 @@
include include/uapi/asm-generic/Kbuild.asm
generic-y += kvm_para.h
-generic-y += shmparam.h
generic-y += ucontext.h
diff --git a/arch/x86/include/asm/page_64_types.h b/arch/x86/include/asm/page_64_types.h
index 8f65728..0ce558a 100644
--- a/arch/x86/include/asm/page_64_types.h
+++ b/arch/x86/include/asm/page_64_types.h
@@ -7,7 +7,11 @@
#endif
#ifdef CONFIG_KASAN
+#ifdef CONFIG_KASAN_EXTRA
+#define KASAN_STACK_ORDER 2
+#else
#define KASAN_STACK_ORDER 1
+#endif
#else
#define KASAN_STACK_ORDER 0
#endif
diff --git a/fs/autofs/expire.c b/fs/autofs/expire.c
index d441244..28d9c2b 100644
--- a/fs/autofs/expire.c
+++ b/fs/autofs/expire.c
@@ -596,7 +596,6 @@
pkt.len = dentry->d_name.len;
memcpy(pkt.name, dentry->d_name.name, pkt.len);
pkt.name[pkt.len] = '\0';
- dput(dentry);
if (copy_to_user(pkt_p, &pkt, sizeof(struct autofs_packet_expire)))
ret = -EFAULT;
@@ -609,6 +608,8 @@
complete_all(&ino->expire_complete);
spin_unlock(&sbi->fs_lock);
+ dput(dentry);
+
return ret;
}
diff --git a/fs/autofs/inode.c b/fs/autofs/inode.c
index 0e8ea2d..078992e 100644
--- a/fs/autofs/inode.c
+++ b/fs/autofs/inode.c
@@ -266,8 +266,10 @@
}
root_inode = autofs_get_inode(s, S_IFDIR | 0755);
root = d_make_root(root_inode);
- if (!root)
+ if (!root) {
+ ret = -ENOMEM;
goto fail_ino;
+ }
pipe = NULL;
root->d_fsdata = ino;
diff --git a/fs/drop_caches.c b/fs/drop_caches.c
index 8237701..d31b6c7 100644
--- a/fs/drop_caches.c
+++ b/fs/drop_caches.c
@@ -21,8 +21,13 @@
spin_lock(&sb->s_inode_list_lock);
list_for_each_entry(inode, &sb->s_inodes, i_sb_list) {
spin_lock(&inode->i_lock);
+ /*
+ * We must skip inodes in unusual state. We may also skip
+ * inodes without pages but we deliberately won't in case
+ * we need to reschedule to avoid softlockups.
+ */
if ((inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) ||
- (inode->i_mapping->nrpages == 0)) {
+ (inode->i_mapping->nrpages == 0 && !need_resched())) {
spin_unlock(&inode->i_lock);
continue;
}
@@ -30,6 +35,7 @@
spin_unlock(&inode->i_lock);
spin_unlock(&sb->s_inode_list_lock);
+ cond_resched();
invalidate_mapping_pages(inode->i_mapping, 0, -1);
iput(toput_inode);
toput_inode = inode;
diff --git a/fs/proc/generic.c b/fs/proc/generic.c
index 8ae1094..e39bac9 100644
--- a/fs/proc/generic.c
+++ b/fs/proc/generic.c
@@ -256,7 +256,7 @@
inode = proc_get_inode(dir->i_sb, de);
if (!inode)
return ERR_PTR(-ENOMEM);
- d_set_d_op(dentry, &proc_misc_dentry_ops);
+ d_set_d_op(dentry, de->proc_dops);
return d_splice_alias(inode, dentry);
}
read_unlock(&proc_subdir_lock);
@@ -429,6 +429,8 @@
INIT_LIST_HEAD(&ent->pde_openers);
proc_set_user(ent, (*parent)->uid, (*parent)->gid);
+ ent->proc_dops = &proc_misc_dentry_ops;
+
out:
return ent;
}
diff --git a/fs/proc/internal.h b/fs/proc/internal.h
index 5185d7f..95b1419 100644
--- a/fs/proc/internal.h
+++ b/fs/proc/internal.h
@@ -44,6 +44,7 @@
struct completion *pde_unload_completion;
const struct inode_operations *proc_iops;
const struct file_operations *proc_fops;
+ const struct dentry_operations *proc_dops;
union {
const struct seq_operations *seq_ops;
int (*single_show)(struct seq_file *, void *);
diff --git a/fs/proc/proc_net.c b/fs/proc/proc_net.c
index d5e0fcb..a7b1243 100644
--- a/fs/proc/proc_net.c
+++ b/fs/proc/proc_net.c
@@ -38,6 +38,22 @@
return maybe_get_net(PDE_NET(PDE(inode)));
}
+static int proc_net_d_revalidate(struct dentry *dentry, unsigned int flags)
+{
+ return 0;
+}
+
+static const struct dentry_operations proc_net_dentry_ops = {
+ .d_revalidate = proc_net_d_revalidate,
+ .d_delete = always_delete_dentry,
+};
+
+static void pde_force_lookup(struct proc_dir_entry *pde)
+{
+ /* /proc/net/ entries can be changed under us by setns(CLONE_NEWNET) */
+ pde->proc_dops = &proc_net_dentry_ops;
+}
+
static int seq_open_net(struct inode *inode, struct file *file)
{
unsigned int state_size = PDE(inode)->state_size;
@@ -90,6 +106,7 @@
p = proc_create_reg(name, mode, &parent, data);
if (!p)
return NULL;
+ pde_force_lookup(p);
p->proc_fops = &proc_net_seq_fops;
p->seq_ops = ops;
p->state_size = state_size;
@@ -133,6 +150,7 @@
p = proc_create_reg(name, mode, &parent, data);
if (!p)
return NULL;
+ pde_force_lookup(p);
p->proc_fops = &proc_net_seq_fops;
p->seq_ops = ops;
p->state_size = state_size;
@@ -181,6 +199,7 @@
p = proc_create_reg(name, mode, &parent, data);
if (!p)
return NULL;
+ pde_force_lookup(p);
p->proc_fops = &proc_net_single_fops;
p->single_show = show;
return proc_register(parent, p);
@@ -223,6 +242,7 @@
p = proc_create_reg(name, mode, &parent, data);
if (!p)
return NULL;
+ pde_force_lookup(p);
p->proc_fops = &proc_net_single_fops;
p->single_show = show;
p->write = write;
diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
index 07da5c6..368267c 100644
--- a/include/linux/memory_hotplug.h
+++ b/include/linux/memory_hotplug.h
@@ -21,14 +21,16 @@
* walkers which rely on the fully initialized page->flags and others
* should use this rather than pfn_valid && pfn_to_page
*/
-#define pfn_to_online_page(pfn) \
-({ \
- struct page *___page = NULL; \
- unsigned long ___nr = pfn_to_section_nr(pfn); \
- \
- if (___nr < NR_MEM_SECTIONS && online_section_nr(___nr))\
- ___page = pfn_to_page(pfn); \
- ___page; \
+#define pfn_to_online_page(pfn) \
+({ \
+ struct page *___page = NULL; \
+ unsigned long ___pfn = pfn; \
+ unsigned long ___nr = pfn_to_section_nr(___pfn); \
+ \
+ if (___nr < NR_MEM_SECTIONS && online_section_nr(___nr) && \
+ pfn_valid_within(___pfn)) \
+ ___page = pfn_to_page(___pfn); \
+ ___page; \
})
/*
diff --git a/include/linux/sched/coredump.h b/include/linux/sched/coredump.h
index ec912d0..ecdc654 100644
--- a/include/linux/sched/coredump.h
+++ b/include/linux/sched/coredump.h
@@ -71,6 +71,7 @@
#define MMF_HUGE_ZERO_PAGE 23 /* mm has ever used the global huge zero page */
#define MMF_DISABLE_THP 24 /* disable THP for all VMAs */
#define MMF_OOM_VICTIM 25 /* mm is the oom victim */
+#define MMF_OOM_REAP_QUEUED 26 /* mm was queued for oom_reaper */
#define MMF_DISABLE_THP_MASK (1 << MMF_DISABLE_THP)
#define MMF_INIT_MASK (MMF_DUMPABLE_MASK | MMF_DUMP_FILTER_MASK |\
diff --git a/init/Kconfig b/init/Kconfig
index 513fa54..c9386a3 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -512,6 +512,17 @@
per default but can be enabled through passing psi=1 on the
kernel commandline during boot.
+ This feature adds some code to the task wakeup and sleep
+ paths of the scheduler. The overhead is too low to affect
+ common scheduling-intense workloads in practice (such as
+ webservers, memcache), but it does show up in artificial
+ scheduler stress tests, such as hackbench.
+
+ If you are paranoid and not sure what the kernel will be
+ used for, say Y.
+
+ Say N if unsure.
+
endmenu # "CPU/Task time and stats accounting"
config CPU_ISOLATION
@@ -825,7 +836,7 @@
PIDs controller is designed to stop this from happening.
It should be noted that organisational operations (such as attaching
- to a cgroup hierarchy will *not* be blocked by the PIDs controller),
+ to a cgroup hierarchy) will *not* be blocked by the PIDs controller,
since the PIDs limit only affects a process's ability to fork, not to
attach to a cgroup.
diff --git a/kernel/exit.c b/kernel/exit.c
index 3fb7be0..2639a30 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -558,12 +558,14 @@
return NULL;
}
-static struct task_struct *find_child_reaper(struct task_struct *father)
+static struct task_struct *find_child_reaper(struct task_struct *father,
+ struct list_head *dead)
__releases(&tasklist_lock)
__acquires(&tasklist_lock)
{
struct pid_namespace *pid_ns = task_active_pid_ns(father);
struct task_struct *reaper = pid_ns->child_reaper;
+ struct task_struct *p, *n;
if (likely(reaper != father))
return reaper;
@@ -579,6 +581,12 @@
panic("Attempted to kill init! exitcode=0x%08x\n",
father->signal->group_exit_code ?: father->exit_code);
}
+
+ list_for_each_entry_safe(p, n, dead, ptrace_entry) {
+ list_del_init(&p->ptrace_entry);
+ release_task(p);
+ }
+
zap_pid_ns_processes(pid_ns);
write_lock_irq(&tasklist_lock);
@@ -668,7 +676,7 @@
exit_ptrace(father, dead);
/* Can drop and reacquire tasklist_lock */
- reaper = find_child_reaper(father);
+ reaper = find_child_reaper(father, dead);
if (list_empty(&father->children))
return;
diff --git a/kernel/sched/psi.c b/kernel/sched/psi.c
index fe24de3..c348478 100644
--- a/kernel/sched/psi.c
+++ b/kernel/sched/psi.c
@@ -124,6 +124,7 @@
* sampling of the aggregate task states would be.
*/
+#include "../workqueue_internal.h"
#include <linux/sched/loadavg.h>
#include <linux/seq_file.h>
#include <linux/proc_fs.h>
@@ -480,9 +481,6 @@
groupc->tasks[t]++;
write_seqcount_end(&groupc->seq);
-
- if (!delayed_work_pending(&group->clock_work))
- schedule_delayed_work(&group->clock_work, PSI_FREQ);
}
static struct psi_group *iterate_groups(struct task_struct *task, void **iter)
@@ -513,6 +511,7 @@
{
int cpu = task_cpu(task);
struct psi_group *group;
+ bool wake_clock = true;
void *iter = NULL;
if (!task->pid)
@@ -530,8 +529,22 @@
task->psi_flags &= ~clear;
task->psi_flags |= set;
- while ((group = iterate_groups(task, &iter)))
+ /*
+ * Periodic aggregation shuts off if there is a period of no
+ * task changes, so we wake it back up if necessary. However,
+ * don't do this if the task change is the aggregation worker
+ * itself going to sleep, or we'll ping-pong forever.
+ */
+ if (unlikely((clear & TSK_RUNNING) &&
+ (task->flags & PF_WQ_WORKER) &&
+ wq_worker_last_func(task) == psi_update_work))
+ wake_clock = false;
+
+ while ((group = iterate_groups(task, &iter))) {
psi_group_change(group, cpu, clear, set);
+ if (wake_clock && !delayed_work_pending(&group->clock_work))
+ schedule_delayed_work(&group->clock_work, PSI_FREQ);
+ }
}
void psi_memstall_tick(struct task_struct *task, int cpu)
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 392be4b..fc5d23d 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -910,6 +910,26 @@
}
/**
+ * wq_worker_last_func - retrieve worker's last work function
+ *
+ * Determine the last function a worker executed. This is called from
+ * the scheduler to get a worker's last known identity.
+ *
+ * CONTEXT:
+ * spin_lock_irq(rq->lock)
+ *
+ * Return:
+ * The last work function %current executed as a worker, NULL if it
+ * hasn't executed any work yet.
+ */
+work_func_t wq_worker_last_func(struct task_struct *task)
+{
+ struct worker *worker = kthread_data(task);
+
+ return worker->last_func;
+}
+
+/**
* worker_set_flags - set worker flags and adjust nr_running accordingly
* @worker: self
* @flags: flags to set
@@ -2184,6 +2204,9 @@
if (unlikely(cpu_intensive))
worker_clr_flags(worker, WORKER_CPU_INTENSIVE);
+ /* tag the worker for identification in schedule() */
+ worker->last_func = worker->current_func;
+
/* we're done with it, release */
hash_del(&worker->hentry);
worker->current_work = NULL;
diff --git a/kernel/workqueue_internal.h b/kernel/workqueue_internal.h
index 66fbb5a..cb68b03 100644
--- a/kernel/workqueue_internal.h
+++ b/kernel/workqueue_internal.h
@@ -53,6 +53,9 @@
/* used only by rescuers to point to the target workqueue */
struct workqueue_struct *rescue_wq; /* I: the workqueue to rescue */
+
+ /* used by the scheduler to determine a worker's last known identity */
+ work_func_t last_func;
};
/**
@@ -67,9 +70,10 @@
/*
* Scheduler hooks for concurrency managed workqueue. Only to be used from
- * sched/core.c and workqueue.c.
+ * sched/ and workqueue.c.
*/
void wq_worker_waking_up(struct task_struct *task, int cpu);
struct task_struct *wq_worker_sleeping(struct task_struct *task);
+work_func_t wq_worker_last_func(struct task_struct *task);
#endif /* _KERNEL_WORKQUEUE_INTERNAL_H */
diff --git a/lib/test_kmod.c b/lib/test_kmod.c
index d82d022..9cf7762 100644
--- a/lib/test_kmod.c
+++ b/lib/test_kmod.c
@@ -632,7 +632,7 @@
config->test_driver = NULL;
kfree_const(config->test_fs);
- config->test_driver = NULL;
+ config->test_fs = NULL;
}
static void kmod_config_free(struct kmod_test_device *test_dev)
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index df2e7dd..afef616 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -4268,7 +4268,8 @@
break;
}
if (ret & VM_FAULT_RETRY) {
- if (nonblocking)
+ if (nonblocking &&
+ !(fault_flags & FAULT_FLAG_RETRY_NOWAIT))
*nonblocking = 0;
*nr_pages = 0;
/*
diff --git a/mm/kasan/Makefile b/mm/kasan/Makefile
index 0a14fcf..e2bb06c1 100644
--- a/mm/kasan/Makefile
+++ b/mm/kasan/Makefile
@@ -5,6 +5,7 @@
UBSAN_SANITIZE_tags.o := n
KCOV_INSTRUMENT := n
+CFLAGS_REMOVE_common.o = -pg
CFLAGS_REMOVE_generic.o = -pg
# Function splitter causes unnecessary splits in __asan_load1/__asan_store1
# see: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63533
diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index 7c72f2a..831be5f 100644
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -372,7 +372,8 @@
if (fail || tk->addr_valid == 0) {
pr_err("Memory failure: %#lx: forcibly killing %s:%d because of failure to unmap corrupted page\n",
pfn, tk->tsk->comm, tk->tsk->pid);
- force_sig(SIGKILL, tk->tsk);
+ do_send_sig_info(SIGKILL, SEND_SIG_PRIV,
+ tk->tsk, PIDTYPE_PID);
}
/*
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index b9a667d..124e794 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -1233,7 +1233,8 @@
bool is_mem_section_removable(unsigned long start_pfn, unsigned long nr_pages)
{
struct page *page = pfn_to_page(start_pfn);
- struct page *end_page = page + nr_pages;
+ unsigned long end_pfn = min(start_pfn + nr_pages, zone_end_pfn(page_zone(page)));
+ struct page *end_page = pfn_to_page(end_pfn);
/* Check the starting page of each pageblock within the range */
for (; page < end_page; page = next_active_pageblock(page)) {
@@ -1273,6 +1274,9 @@
i++;
if (i == MAX_ORDER_NR_PAGES || pfn + i >= end_pfn)
continue;
+ /* Check if we got outside of the zone */
+ if (zone && !zone_spans_pfn(zone, pfn + i))
+ return 0;
page = pfn_to_page(pfn + i);
if (zone && page_zone(page) != zone)
return 0;
@@ -1301,23 +1305,27 @@
static unsigned long scan_movable_pages(unsigned long start, unsigned long end)
{
unsigned long pfn;
- struct page *page;
+
for (pfn = start; pfn < end; pfn++) {
- if (pfn_valid(pfn)) {
- page = pfn_to_page(pfn);
- if (PageLRU(page))
- return pfn;
- if (__PageMovable(page))
- return pfn;
- if (PageHuge(page)) {
- if (hugepage_migration_supported(page_hstate(page)) &&
- page_huge_active(page))
- return pfn;
- else
- pfn = round_up(pfn + 1,
- 1 << compound_order(page)) - 1;
- }
- }
+ struct page *page, *head;
+ unsigned long skip;
+
+ if (!pfn_valid(pfn))
+ continue;
+ page = pfn_to_page(pfn);
+ if (PageLRU(page))
+ return pfn;
+ if (__PageMovable(page))
+ return pfn;
+
+ if (!PageHuge(page))
+ continue;
+ head = compound_head(page);
+ if (hugepage_migration_supported(page_hstate(head)) &&
+ page_huge_active(head))
+ return pfn;
+ skip = (1 << compound_order(head)) - (page - head);
+ pfn += skip - 1;
}
return 0;
}
@@ -1344,7 +1352,6 @@
{
unsigned long pfn;
struct page *page;
- int not_managed = 0;
int ret = 0;
LIST_HEAD(source);
@@ -1392,7 +1399,6 @@
else
ret = isolate_movable_page(page, ISOLATE_UNEVICTABLE);
if (!ret) { /* Success */
- put_page(page);
list_add_tail(&page->lru, &source);
if (!__PageMovable(page))
inc_node_page_state(page, NR_ISOLATED_ANON +
@@ -1401,22 +1407,10 @@
} else {
pr_warn("failed to isolate pfn %lx\n", pfn);
dump_page(page, "isolation failed");
- put_page(page);
- /* Because we don't have big zone->lock. we should
- check this again here. */
- if (page_count(page)) {
- not_managed++;
- ret = -EBUSY;
- break;
- }
}
+ put_page(page);
}
if (!list_empty(&source)) {
- if (not_managed) {
- putback_movable_pages(&source);
- goto out;
- }
-
/* Allocate a new page from the nearest neighbor node */
ret = migrate_pages(&source, new_node_page, NULL, 0,
MIGRATE_SYNC, MR_MEMORY_HOTPLUG);
@@ -1429,7 +1423,7 @@
putback_movable_pages(&source);
}
}
-out:
+
return ret;
}
@@ -1576,7 +1570,6 @@
we assume this for now. .*/
if (!test_pages_in_a_zone(start_pfn, end_pfn, &valid_start,
&valid_end)) {
- mem_hotplug_done();
ret = -EINVAL;
reason = "multizone range";
goto failed_removal;
@@ -1591,7 +1584,6 @@
MIGRATE_MOVABLE,
SKIP_HWPOISON | REPORT_FAILURE);
if (ret) {
- mem_hotplug_done();
reason = "failure to isolate range";
goto failed_removal;
}
diff --git a/mm/migrate.c b/mm/migrate.c
index a16b150..d4fd680 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -709,7 +709,6 @@
/* Simple case, sync compaction */
if (mode != MIGRATE_ASYNC) {
do {
- get_bh(bh);
lock_buffer(bh);
bh = bh->b_this_page;
@@ -720,18 +719,15 @@
/* async case, we cannot block on lock_buffer so use trylock_buffer */
do {
- get_bh(bh);
if (!trylock_buffer(bh)) {
/*
* We failed to lock the buffer and cannot stall in
* async migration. Release the taken locks
*/
struct buffer_head *failed_bh = bh;
- put_bh(failed_bh);
bh = head;
while (bh != failed_bh) {
unlock_buffer(bh);
- put_bh(bh);
bh = bh->b_this_page;
}
return false;
@@ -818,7 +814,6 @@
bh = head;
do {
unlock_buffer(bh);
- put_bh(bh);
bh = bh->b_this_page;
} while (bh != head);
@@ -1135,10 +1130,13 @@
* If migration is successful, decrease refcount of the newpage
* which will not free the page because new page owner increased
* refcounter. As well, if it is LRU page, add the page to LRU
- * list in here.
+ * list in here. Use the old state of the isolated source page to
+ * determine if we migrated a LRU page. newpage was already unlocked
+ * and possibly modified by its owner - don't rely on the page
+ * state.
*/
if (rc == MIGRATEPAGE_SUCCESS) {
- if (unlikely(__PageMovable(newpage)))
+ if (unlikely(!is_lru))
put_page(newpage);
else
putback_lru_page(newpage);
diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index f0e8cd9..26ea863 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -647,8 +647,8 @@
static void wake_oom_reaper(struct task_struct *tsk)
{
- /* tsk is already queued? */
- if (tsk == oom_reaper_list || tsk->oom_reaper_list)
+ /* mm is already queued? */
+ if (test_and_set_bit(MMF_OOM_REAP_QUEUED, &tsk->signal->oom_mm->flags))
return;
get_task_struct(tsk);
@@ -975,6 +975,13 @@
* still freeing memory.
*/
read_lock(&tasklist_lock);
+
+ /*
+ * The task 'p' might have already exited before reaching here. The
+ * put_task_struct() will free task_struct 'p' while the loop still try
+ * to access the field of 'p', so, get an extra reference.
+ */
+ get_task_struct(p);
for_each_thread(p, t) {
list_for_each_entry(child, &t->children, sibling) {
unsigned int child_points;
@@ -994,6 +1001,7 @@
}
}
}
+ put_task_struct(p);
read_unlock(&tasklist_lock);
/*
diff --git a/tools/testing/selftests/proc/.gitignore b/tools/testing/selftests/proc/.gitignore
index 82121a8..29bac5e 100644
--- a/tools/testing/selftests/proc/.gitignore
+++ b/tools/testing/selftests/proc/.gitignore
@@ -10,4 +10,5 @@
/proc-uptime-002
/read
/self
+/setns-dcache
/thread-self
diff --git a/tools/testing/selftests/proc/Makefile b/tools/testing/selftests/proc/Makefile
index 1c12c34..434d033 100644
--- a/tools/testing/selftests/proc/Makefile
+++ b/tools/testing/selftests/proc/Makefile
@@ -14,6 +14,7 @@
TEST_GEN_PROGS += proc-uptime-002
TEST_GEN_PROGS += read
TEST_GEN_PROGS += self
+TEST_GEN_PROGS += setns-dcache
TEST_GEN_PROGS += thread-self
include ../lib.mk
diff --git a/tools/testing/selftests/proc/setns-dcache.c b/tools/testing/selftests/proc/setns-dcache.c
new file mode 100644
index 0000000..60ab197
--- /dev/null
+++ b/tools/testing/selftests/proc/setns-dcache.c
@@ -0,0 +1,129 @@
+/*
+ * Copyright © 2019 Alexey Dobriyan <adobriyan@gmail.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+/*
+ * Test that setns(CLONE_NEWNET) points to new /proc/net content even
+ * if old one is in dcache.
+ *
+ * FIXME /proc/net/unix is under CONFIG_UNIX which can be disabled.
+ */
+#undef NDEBUG
+#include <assert.h>
+#include <errno.h>
+#include <sched.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <sys/socket.h>
+
+static pid_t pid = -1;
+
+static void f(void)
+{
+ if (pid > 0) {
+ kill(pid, SIGTERM);
+ }
+}
+
+int main(void)
+{
+ int fd[2];
+ char _ = 0;
+ int nsfd;
+
+ atexit(f);
+
+ /* Check for priviledges and syscall availability straight away. */
+ if (unshare(CLONE_NEWNET) == -1) {
+ if (errno == ENOSYS || errno == EPERM) {
+ return 4;
+ }
+ return 1;
+ }
+ /* Distinguisher between two otherwise empty net namespaces. */
+ if (socket(AF_UNIX, SOCK_STREAM, 0) == -1) {
+ return 1;
+ }
+
+ if (pipe(fd) == -1) {
+ return 1;
+ }
+
+ pid = fork();
+ if (pid == -1) {
+ return 1;
+ }
+
+ if (pid == 0) {
+ if (unshare(CLONE_NEWNET) == -1) {
+ return 1;
+ }
+
+ if (write(fd[1], &_, 1) != 1) {
+ return 1;
+ }
+
+ pause();
+
+ return 0;
+ }
+
+ if (read(fd[0], &_, 1) != 1) {
+ return 1;
+ }
+
+ {
+ char buf[64];
+ snprintf(buf, sizeof(buf), "/proc/%u/ns/net", pid);
+ nsfd = open(buf, O_RDONLY);
+ if (nsfd == -1) {
+ return 1;
+ }
+ }
+
+ /* Reliably pin dentry into dcache. */
+ (void)open("/proc/net/unix", O_RDONLY);
+
+ if (setns(nsfd, CLONE_NEWNET) == -1) {
+ return 1;
+ }
+
+ kill(pid, SIGTERM);
+ pid = 0;
+
+ {
+ char buf[4096];
+ ssize_t rv;
+ int fd;
+
+ fd = open("/proc/net/unix", O_RDONLY);
+ if (fd == -1) {
+ return 1;
+ }
+
+#define S "Num RefCount Protocol Flags Type St Inode Path\n"
+ rv = read(fd, buf, sizeof(buf));
+
+ assert(rv == strlen(S));
+ assert(memcmp(buf, S, strlen(S)) == 0);
+ }
+
+ return 0;
+}