The patch titled Subject: mm: change cpuhotplug lock order in lru_add_drain_all() has been removed from the -mm tree. Its filename was mm-change-cpuhotplug-lock-order-in-lru_add_drain_all.patch This patch was dropped because an updated version will be merged ------------------------------------------------------ From: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Subject: mm: change cpuhotplug lock order in lru_add_drain_all() [ 131.022567] ============================================ [ 131.023034] WARNING: possible recursive locking detected [ 131.023034] 4.12.0-rc7-next-20170630 #10 Not tainted [ 131.023034] -------------------------------------------- [ 131.023034] bash/2266 is trying to acquire lock: [ 131.023034] (cpu_hotplug_lock.rw_sem){++++++}, at: [<ffffffff8117fcd2>] lru_add_drain_all+0x42/0x190 [ 131.023034] but task is already holding lock: [ 131.023034] (cpu_hotplug_lock.rw_sem){++++++}, at: [<ffffffff811d5489>] mem_hotplug_begin+0x9/0x20 [ 131.023034] other info that might help us debug this: [ 131.023034] Possible unsafe locking scenario: [ 131.023034] CPU0 [ 131.023034] ---- [ 131.023034] lock(cpu_hotplug_lock.rw_sem); [ 131.023034] lock(cpu_hotplug_lock.rw_sem); [ 131.023034] *** DEADLOCK *** [ 131.023034] May be due to missing lock nesting notation [ 131.023034] 8 locks held by bash/2266: [ 131.023034] #0: (sb_writers#8){.+.+.+}, at: [<ffffffff811e81f8>] vfs_write+0x1a8/0x1d0 [ 131.023034] #1: (&of->mutex){+.+.+.}, at: [<ffffffff81274b2c>] kernfs_fop_write+0xfc/0x1b0 [ 131.023034] #2: (s_active#48){.+.+.+}, at: [<ffffffff81274b34>] kernfs_fop_write+0x104/0x1b0 [ 131.023034] #3: (device_hotplug_lock){+.+.+.}, at: [<ffffffff816d4810>] lock_device_hotplug_sysfs+0x10/0x40 [ 131.023034] #4: (cpu_hotplug_lock.rw_sem){++++++}, at: [<ffffffff811d5489>] mem_hotplug_begin+0x9/0x20 [ 131.023034] #5: (mem_hotplug_lock.rw_sem){++++++}, at: [<ffffffff810ada81>] percpu_down_write+0x21/0x110 [ 131.023034] #6: (&dev->mutex){......}, at: [<ffffffff816d5bd5>] device_offline+0x45/0xb0 [ 131.023034] #7: (lock#3){+.+...}, at: [<ffffffff8117fccd>] lru_add_drain_all+0x3d/0x190 [ 131.023034] stack backtrace: [ 131.023034] CPU: 0 PID: 2266 Comm: bash Not tainted 4.12.0-rc7-next-20170630 #10 [ 131.023034] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.10.2-0-g5f4c7b1-prebuilt.qemu-project.org 04/01/2014 [ 131.023034] Call Trace: [ 131.023034] dump_stack+0x85/0xc7 [ 131.023034] __lock_acquire+0x1747/0x17a0 [ 131.023034] ? lru_add_drain_all+0x3d/0x190 [ 131.023034] ? __mutex_lock+0x218/0x940 [ 131.023034] ? trace_hardirqs_on+0xd/0x10 [ 131.023034] lock_acquire+0x103/0x200 [ 131.023034] ? lock_acquire+0x103/0x200 [ 131.023034] ? lru_add_drain_all+0x42/0x190 [ 131.023034] cpus_read_lock+0x3d/0x80 [ 131.023034] ? lru_add_drain_all+0x42/0x190 [ 131.023034] lru_add_drain_all+0x42/0x190 [ 131.023034] __offline_pages.constprop.25+0x5de/0x870 [ 131.023034] offline_pages+0xc/0x10 [ 131.023034] memory_subsys_offline+0x43/0x70 [ 131.023034] device_offline+0x83/0xb0 [ 131.023034] store_mem_state+0xdb/0xe0 [ 131.023034] dev_attr_store+0x13/0x20 [ 131.023034] sysfs_kf_write+0x40/0x50 [ 131.023034] kernfs_fop_write+0x130/0x1b0 [ 131.023034] __vfs_write+0x23/0x130 [ 131.023034] ? rcu_read_lock_sched_held+0x6d/0x80 [ 131.023034] ? rcu_sync_lockdep_assert+0x2a/0x50 [ 131.023034] ? __sb_start_write+0xd4/0x1c0 [ 131.023034] ? vfs_write+0x1a8/0x1d0 [ 131.023034] vfs_write+0xc8/0x1d0 [ 131.023034] SyS_write+0x44/0xa0 [ 131.023034] entry_SYSCALL_64_fastpath+0x1f/0xbe Reported-by: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx> Tested-by: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxxxx> Cc: Vlastimil Babka <vbabka@xxxxxxx> Cc: Daniel Kiper <dkiper@xxxxxxxxxxxx> Cc: Vladimir Davydov <vdavydov.dev@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/swap.h | 1 + mm/memory_hotplug.c | 4 ++-- mm/swap.c | 11 ++++++++--- 3 files changed, 11 insertions(+), 5 deletions(-) diff -puN include/linux/swap.h~mm-change-cpuhotplug-lock-order-in-lru_add_drain_all include/linux/swap.h --- a/include/linux/swap.h~mm-change-cpuhotplug-lock-order-in-lru_add_drain_all +++ a/include/linux/swap.h @@ -277,6 +277,7 @@ extern void mark_page_accessed(struct pa extern void lru_add_drain(void); extern void lru_add_drain_cpu(int cpu); extern void lru_add_drain_all(void); +extern void lru_add_drain_all_cpuslocked(void); extern void rotate_reclaimable_page(struct page *page); extern void deactivate_file_page(struct page *page); extern void mark_page_lazyfree(struct page *page); diff -puN mm/memory_hotplug.c~mm-change-cpuhotplug-lock-order-in-lru_add_drain_all mm/memory_hotplug.c --- a/mm/memory_hotplug.c~mm-change-cpuhotplug-lock-order-in-lru_add_drain_all +++ a/mm/memory_hotplug.c @@ -1670,7 +1670,7 @@ repeat: goto failed_removal; ret = 0; if (drain) { - lru_add_drain_all(); + lru_add_drain_all_cpuslocked(); cond_resched(); drain_all_pages(zone); } @@ -1691,7 +1691,7 @@ repeat: } } /* drain all zone's lru pagevec, this is asynchronous... */ - lru_add_drain_all(); + lru_add_drain_all_cpuslocked(); yield(); /* drain pcp pages, this is synchronous. */ drain_all_pages(zone); diff -puN mm/swap.c~mm-change-cpuhotplug-lock-order-in-lru_add_drain_all mm/swap.c --- a/mm/swap.c~mm-change-cpuhotplug-lock-order-in-lru_add_drain_all +++ a/mm/swap.c @@ -688,7 +688,7 @@ static void lru_add_drain_per_cpu(struct static DEFINE_PER_CPU(struct work_struct, lru_add_drain_work); -void lru_add_drain_all(void) +void lru_add_drain_all_cpuslocked(void) { static DEFINE_MUTEX(lock); static struct cpumask has_work; @@ -702,7 +702,6 @@ void lru_add_drain_all(void) return; mutex_lock(&lock); - get_online_cpus(); cpumask_clear(&has_work); for_each_online_cpu(cpu) { @@ -722,10 +721,16 @@ void lru_add_drain_all(void) for_each_cpu(cpu, &has_work) flush_work(&per_cpu(lru_add_drain_work, cpu)); - put_online_cpus(); mutex_unlock(&lock); } +void lru_add_drain_all(void) +{ + get_online_cpus(); + lru_add_drain_all_cpuslocked(); + put_online_cpus(); +} + /** * release_pages - batched put_page() * @pages: array of pages to release _ Patches currently in -mm which might be from tglx@xxxxxxxxxxxxx are -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html