In __remove_section(), we locked pgdat_resize_lock when calling
sparse_remove_one_section(). This lock will disable irq. But we don't need
to lock the whole function. If we do some work to free pagetables in
free_section_usemap(), we need to call flush_tlb_all(), which need
irq enabled. Otherwise the WARN_ON_ONCE() in smp_call_function_many()
will be triggered.
If we lock the whole sparse_remove_one_section(), then we come to this call trace:
[ 454.796248] ------------[ cut here ]------------
[ 454.851408] WARNING: at kernel/smp.c:461 smp_call_function_many+0xbd/0x260()
[ 454.935620] Hardware name: PRIMEQUEST 1800E
......
[ 455.652201] Call Trace:
[ 455.681391] [<ffffffff8106e73f>] warn_slowpath_common+0x7f/0xc0
[ 455.753151] [<ffffffff810560a0>] ? leave_mm+0x50/0x50
[ 455.814527] [<ffffffff8106e79a>] warn_slowpath_null+0x1a/0x20
[ 455.884208] [<ffffffff810e7a9d>] smp_call_function_many+0xbd/0x260
[ 455.959082] [<ffffffff810e7ecb>] smp_call_function+0x3b/0x50
[ 456.027722] [<ffffffff810560a0>] ? leave_mm+0x50/0x50
[ 456.089098] [<ffffffff810e7f4b>] on_each_cpu+0x3b/0xc0
[ 456.151512] [<ffffffff81055f0c>] flush_tlb_all+0x1c/0x20
[ 456.216004] [<ffffffff8104f8de>] remove_pagetable+0x14e/0x1d0
[ 456.285683] [<ffffffff8104f978>] vmemmap_free+0x18/0x20
[ 456.349139] [<ffffffff811b8797>] sparse_remove_one_section+0xf7/0x100
[ 456.427126] [<ffffffff811c5fc2>] __remove_section+0xa2/0xb0
[ 456.494726] [<ffffffff811c6070>] __remove_pages+0xa0/0xd0
[ 456.560258] [<ffffffff81669c7b>] arch_remove_memory+0x6b/0xc0
[ 456.629937] [<ffffffff8166ad28>] remove_memory+0xb8/0xf0
[ 456.694431] [<ffffffff813e686f>] acpi_memory_device_remove+0x53/0x96
[ 456.771379] [<ffffffff813b33c4>] acpi_device_remove+0x90/0xb2
[ 456.841059] [<ffffffff8144b02c>] __device_release_driver+0x7c/0xf0
[ 456.915928] [<ffffffff8144b1af>] device_release_driver+0x2f/0x50
[ 456.988719] [<ffffffff813b4476>] acpi_bus_remove+0x32/0x6d
[ 457.055285] [<ffffffff813b4542>] acpi_bus_trim+0x91/0x102
[ 457.120814] [<ffffffff813b463b>] acpi_bus_hot_remove_device+0x88/0x16b
[ 457.199840] [<ffffffff813afda7>] acpi_os_execute_deferred+0x27/0x34
[ 457.275756] [<ffffffff81091ece>] process_one_work+0x20e/0x5c0
[ 457.345434] [<ffffffff81091e5f>] ? process_one_work+0x19f/0x5c0
[ 457.417190] [<ffffffff813afd80>] ? acpi_os_wait_events_complete+0x23/0x23
[ 457.499332] [<ffffffff81093f6e>] worker_thread+0x12e/0x370
[ 457.565896] [<ffffffff81093e40>] ? manage_workers+0x180/0x180
[ 457.635574] [<ffffffff8109a09e>] kthread+0xee/0x100
[ 457.694871] [<ffffffff810dfaf9>] ? __lock_release+0x129/0x190
[ 457.764552] [<ffffffff81099fb0>] ? __init_kthread_worker+0x70/0x70
[ 457.839427] [<ffffffff81690aac>] ret_from_fork+0x7c/0xb0
[ 457.903914] [<ffffffff81099fb0>] ? __init_kthread_worker+0x70/0x70
[ 457.978784] ---[ end trace 25e85300f542aa01 ]---
Signed-off-by: Tang Chen <tangchen@xxxxxxxxxxxxxx>
Signed-off-by: Lai Jiangshan <laijs@xxxxxxxxxxxxxx>
Signed-off-by: Wen Congyang <wency@xxxxxxxxxxxxxx>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx>
---
mm/memory_hotplug.c | 4 ----
mm/sparse.c | 5 ++++-
2 files changed, 4 insertions(+), 5 deletions(-)
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index 0682d2a..674e791 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -442,8 +442,6 @@ static int __remove_section(struct zone *zone, struct mem_section *ms)
#else
static int __remove_section(struct zone *zone, struct mem_section *ms)
{
- unsigned long flags;
- struct pglist_data *pgdat = zone->zone_pgdat;
int ret = -EINVAL;
if (!valid_section(ms))
@@ -453,9 +451,7 @@ static int __remove_section(struct zone *zone, struct mem_section *ms)
if (ret)
return ret;
- pgdat_resize_lock(pgdat, &flags);
sparse_remove_one_section(zone, ms);
- pgdat_resize_unlock(pgdat, &flags);
return 0;
}
#endif
diff --git a/mm/sparse.c b/mm/sparse.c
index aadbb2a..05ca73a 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -796,8 +796,10 @@ static inline void clear_hwpoisoned_pages(struct page *memmap, int nr_pages)
void sparse_remove_one_section(struct zone *zone, struct mem_section *ms)
{
struct page *memmap = NULL;
- unsigned long *usemap = NULL;
+ unsigned long *usemap = NULL, flags;
+ struct pglist_data *pgdat = zone->zone_pgdat;
+ pgdat_resize_lock(pgdat, &flags);
if (ms->section_mem_map) {
usemap = ms->pageblock_flags;
memmap = sparse_decode_mem_map(ms->section_mem_map,
@@ -805,6 +807,7 @@ void sparse_remove_one_section(struct zone *zone, struct mem_section *ms)
ms->section_mem_map = 0;
ms->pageblock_flags = NULL;
}
+ pgdat_resize_unlock(pgdat, &flags);
clear_hwpoisoned_pages(memmap, PAGES_PER_SECTION);
free_section_usemap(memmap, usemap);
--
1.7.1
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