mirror of https://gitee.com/openkylin/linux.git
cb5490a5ee
Fix a bug where a kernel warning is triggered when performing a memory hotplug on ppc64. This warning may also occur on any architecture that uses the memory_probe_store interface. WARNING: at drivers/base/memory.c:200 CPU: 9 PID: 13042 Comm: systemd-udevd Not tainted 4.4.0-rc4-00113-g0bd0f1e-dirty #7 NIP [c00000000055e034] pages_correctly_reserved+0x134/0x1b0 LR [c00000000055e7f8] memory_subsys_online+0x68/0x140 Call Trace: memory_subsys_online+0x68/0x140 device_online+0xb4/0x120 store_mem_state+0xb0/0x180 dev_attr_store+0x34/0x60 sysfs_kf_write+0x64/0xa0 kernfs_fop_write+0x17c/0x1e0 __vfs_write+0x40/0x160 vfs_write+0xb8/0x200 SyS_write+0x60/0x110 system_call+0x38/0xd0 The warning is triggered because there is a udev rule that automatically tries to online memory after it has been added. The udev rule varies from distro to distro, but will generally look something like: SUBSYSTEM=="memory", ACTION=="add", ATTR{state}=="offline", ATTR{state}="online" On any architecture that uses memory_probe_store to reserve memory, the udev rule will be triggered after the first section of the block is reserved and will subsequently attempt to online the entire block, interrupting the memory reservation process and causing the warning. This patch modifies memory_probe_store to add a block of memory with a single call to add_memory as opposed to looping through and adding each section individually. A single call to add_memory is protected by the mem_hotplug mutex which will prevent the udev rule from onlining memory until the reservation of the entire block is complete. Signed-off-by: John Allen <jallen@linux.vnet.ibm.com> Acked-by: Dave Hansen <dave.hansen@intel.com> Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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| .. | ||
| power | ||
| regmap | ||
| Kconfig | ||
| Makefile | ||
| attribute_container.c | ||
| base.h | ||
| bus.c | ||
| cacheinfo.c | ||
| class.c | ||
| component.c | ||
| container.c | ||
| core.c | ||
| cpu.c | ||
| dd.c | ||
| devcoredump.c | ||
| devres.c | ||
| devtmpfs.c | ||
| dma-coherent.c | ||
| dma-contiguous.c | ||
| dma-mapping.c | ||
| driver.c | ||
| firmware.c | ||
| firmware_class.c | ||
| hypervisor.c | ||
| init.c | ||
| isa.c | ||
| map.c | ||
| memory.c | ||
| module.c | ||
| node.c | ||
| pinctrl.c | ||
| platform-msi.c | ||
| platform.c | ||
| property.c | ||
| soc.c | ||
| syscore.c | ||
| topology.c | ||
| transport_class.c | ||