linux/drivers/base
Mikhail Zaslonko 4e8346d0be memory_hotplug: fix kernel_panic on offline page processing
Within show_valid_zones() the function test_pages_in_a_zone() should be
called for online memory blocks only.

Otherwise it might lead to the VM_BUG_ON due to uninitialized struct
pages (when CONFIG_DEBUG_VM_PGFLAGS kernel option is set):

 page dumped because: VM_BUG_ON_PAGE(PagePoisoned(p))
 ------------[ cut here ]------------
 Call Trace:
 ([<000000000038f91e>] test_pages_in_a_zone+0xe6/0x168)
  [<0000000000923472>] show_valid_zones+0x5a/0x1a8
  [<0000000000900284>] dev_attr_show+0x3c/0x78
  [<000000000046f6f0>] sysfs_kf_seq_show+0xd0/0x150
  [<00000000003ef662>] seq_read+0x212/0x4b8
  [<00000000003bf202>] __vfs_read+0x3a/0x178
  [<00000000003bf3ca>] vfs_read+0x8a/0x148
  [<00000000003bfa3a>] ksys_read+0x62/0xb8
  [<0000000000bc2220>] system_call+0xdc/0x2d8

That VM_BUG_ON was triggered by the page poisoning introduced in
mm/sparse.c with the git commit d0dc12e86b ("mm/memory_hotplug:
optimize memory hotplug").

With the same commit the new 'nid' field has been added to the struct
memory_block in order to store and later on derive the node id for
offline pages (instead of accessing struct page which might be
uninitialized).  But one reference to nid in show_valid_zones() function
has been overlooked.  Fixed with current commit.  Also, nr_pages will
not be used any more after test_pages_in_a_zone() call, do not update
it.

Link: http://lkml.kernel.org/r/20180828090539.41491-1-zaslonko@linux.ibm.com
Fixes: d0dc12e86b ("mm/memory_hotplug: optimize memory hotplug")
Signed-off-by: Mikhail Zaslonko <zaslonko@linux.ibm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Pavel Tatashin <pavel.tatashin@microsoft.com>
Cc: <stable@vger.kernel.org>	[4.17+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-09-04 16:45:02 -07:00
..
firmware_loader mm: provide a fallback for PAGE_KERNEL_RO for architectures 2018-08-17 16:20:29 -07:00
power PM / clk: signedness bug in of_pm_clk_add_clks() 2018-08-24 11:52:34 +02:00
regmap regmap: Support non-incrementing registers 2018-08-09 11:15:06 +01:00
test driver core: Remove redundant license text 2017-12-07 18:36:44 +01:00
arch_topology.c Revert "base: arch_topology: fix section mismatch build warnings" 2018-03-15 14:36:20 +01:00
attribute_container.c driver core: Remove redundant license text 2017-12-07 18:36:44 +01:00
base.h driver core: remove unnecessary function extern declare 2018-07-16 13:32:20 +02:00
bus.c driver core: hold dev's parent lock when needed 2018-05-31 10:12:07 +02:00
cacheinfo.c drivers: base: cacheinfo: use OF property_read_u32 instead of get_property,read_number 2018-07-07 17:20:47 +02:00
class.c driver core: Remove redundant license text 2017-12-07 18:36:44 +01:00
component.c component: add debugfs support 2017-12-18 16:51:11 +01:00
container.c driver core: Remove redundant license text 2017-12-07 18:36:44 +01:00
core.c Driver core patches for 4.19-rc1 2018-08-18 11:44:53 -07:00
cpu.c x86/speculation/l1tf: Add sysfs reporting for l1tf 2018-06-20 19:10:00 +02:00
dd.c Merge 4.18-rc7 into driver-core-next 2018-07-30 10:08:09 +02:00
devcon.c drivers: base: Unified device connection lookup 2018-03-22 13:10:29 +01:00
devcoredump.c driver core: Remove redundant license text 2017-12-07 18:36:44 +01:00
devres.c device: Use overflow helpers for devm_kmalloc() 2018-06-05 12:16:51 -07:00
devtmpfs.c kernel: add ksys_unshare() helper; remove in-kernel calls to sys_unshare() 2018-04-02 20:16:06 +02:00
driver.c driver-core: return EINVAL error instead of BUG_ON() 2018-05-25 18:18:45 +02:00
firmware.c driver core: Remove redundant license text 2017-12-07 18:36:44 +01:00
hypervisor.c driver core: Remove redundant license text 2017-12-07 18:36:44 +01:00
init.c base: fix order of OF initialization 2018-07-07 17:54:29 +02:00
isa.c Merge 4.15-rc3 into driver-core-next 2017-12-11 08:50:05 +01:00
Kconfig firmware_loader: move kconfig FW_LOADER entries to its own file 2018-05-14 16:43:10 +02:00
Makefile dma-mapping: move all DMA mapping code to kernel/dma 2018-06-14 08:50:37 +02:00
map.c driver core: Remove redundant license text 2017-12-07 18:36:44 +01:00
memory.c memory_hotplug: fix kernel_panic on offline page processing 2018-09-04 16:45:02 -07:00
module.c driver core: Remove redundant license text 2017-12-07 18:36:44 +01:00
node.c mm/memory_hotplug.c: drop unnecessary checks from register_mem_sect_under_node() 2018-08-17 16:20:29 -07:00
pinctrl.c driver core: Remove redundant license text 2017-12-07 18:36:44 +01:00
platform-msi.c genirq/msi: Limit level-triggered MSI to platform devices 2018-05-13 15:58:59 +02:00
platform.c Power management updates for 4.18-rc1 2018-06-05 09:38:39 -07:00
property.c device property: Get rid of union aliasing 2018-05-17 12:47:21 +02:00
soc.c base: soc: use put_device() instead of kfree() 2018-03-15 14:37:03 +01:00
syscore.c driver core: Remove redundant license text 2017-12-07 18:36:44 +01:00
topology.c driver core: Remove redundant license text 2017-12-07 18:36:44 +01:00
transport_class.c driver core: Remove redundant license text 2017-12-07 18:36:44 +01:00