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
arch_topology.c	Revert "base: arch_topology: fix section mismatch build warnings"	2018-03-15 14:36:20 +01:00
attribute_container.c
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
component.c
container.c
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
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
hypervisor.c
init.c	base: fix order of OF initialization	2018-07-07 17:54:29 +02:00
isa.c
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
memory.c	memory_hotplug: fix kernel_panic on offline page processing	2018-09-04 16:45:02 -07:00
module.c
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
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
topology.c
transport_class.c