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path: root/drivers/acpi/acpi_memhotplug.c
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2019-07-18mm/memory_hotplug: rename walk_memory_range() and pass start+size instead of ↵David Hildenbrand
pfns walk_memory_range() was once used to iterate over sections. Now, it iterates over memory blocks. Rename the function, fixup the documentation. Also, pass start+size instead of PFNs, which is what most callers already have at hand. (we'll rework link_mem_sections() most probably soon) Follow-up patches will rework, simplify, and move walk_memory_blocks() to drivers/base/memory.c. Note: walk_memory_blocks() only works correctly right now if the start_pfn is aligned to a section start. This is the case right now, but we'll generalize the function in a follow up patch so the semantics match the documentation. [akpm@linux-foundation.org: remove unused variable] Link: http://lkml.kernel.org/r/20190614100114.311-5-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Len Brown <lenb@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: David Hildenbrand <david@redhat.com> Cc: Rashmica Gupta <rashmica.g@gmail.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Michael Neuling <mikey@neuling.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Oscar Salvador <osalvador@suse.de> Cc: Michal Hocko <mhocko@suse.com> Cc: Wei Yang <richard.weiyang@gmail.com> Cc: Juergen Gross <jgross@suse.com> Cc: Qian Cai <cai@lca.pw> Cc: Arun KS <arunks@codeaurora.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-21treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 12Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose good title or non infringement see the gnu general public license for more details extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 7 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Steve Winslow <swinslow@gmail.com> Reviewed-by: Jilayne Lovejoy <opensource@jilayne.com> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190519154041.727898173@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-10-31mm/memory_hotplug: make add_memory() take the device_hotplug_lockDavid Hildenbrand
add_memory() currently does not take the device_hotplug_lock, however is aleady called under the lock from arch/powerpc/platforms/pseries/hotplug-memory.c drivers/acpi/acpi_memhotplug.c to synchronize against CPU hot-remove and similar. In general, we should hold the device_hotplug_lock when adding memory to synchronize against online/offline request (e.g. from user space) - which already resulted in lock inversions due to device_lock() and mem_hotplug_lock - see 30467e0b3be ("mm, hotplug: fix concurrent memory hot-add deadlock"). add_memory()/add_memory_resource() will create memory block devices, so this really feels like the right thing to do. Holding the device_hotplug_lock makes sure that a memory block device can really only be accessed (e.g. via .online/.state) from user space, once the memory has been fully added to the system. The lock is not held yet in drivers/xen/balloon.c arch/powerpc/platforms/powernv/memtrace.c drivers/s390/char/sclp_cmd.c drivers/hv/hv_balloon.c So, let's either use the locked variants or take the lock. Don't export add_memory_resource(), as it once was exported to be used by XEN, which is never built as a module. If somebody requires it, we also have to export a locked variant (as device_hotplug_lock is never exported). Link: http://lkml.kernel.org/r/20180925091457.28651-3-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Pavel Tatashin <pavel.tatashin@microsoft.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Rashmica Gupta <rashmica.g@gmail.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Len Brown <lenb@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Juergen Gross <jgross@suse.com> Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com> Cc: John Allen <jallen@linux.vnet.ibm.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Mathieu Malaterre <malat@debian.org> Cc: Pavel Tatashin <pavel.tatashin@microsoft.com> Cc: YASUAKI ISHIMATSU <yasu.isimatu@gmail.com> Cc: Balbir Singh <bsingharora@gmail.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Michael Neuling <mikey@neuling.org> Cc: Philippe Ombredanne <pombredanne@nexb.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-31mm/memory_hotplug: make remove_memory() take the device_hotplug_lockDavid Hildenbrand
Patch series "mm: online/offline_pages called w.o. mem_hotplug_lock", v3. Reading through the code and studying how mem_hotplug_lock is to be used, I noticed that there are two places where we can end up calling device_online()/device_offline() - online_pages()/offline_pages() without the mem_hotplug_lock. And there are other places where we call device_online()/device_offline() without the device_hotplug_lock. While e.g. echo "online" > /sys/devices/system/memory/memory9/state is fine, e.g. echo 1 > /sys/devices/system/memory/memory9/online Will not take the mem_hotplug_lock. However the device_lock() and device_hotplug_lock. E.g. via memory_probe_store(), we can end up calling add_memory()->online_pages() without the device_hotplug_lock. So we can have concurrent callers in online_pages(). We e.g. touch in online_pages() basically unprotected zone->present_pages then. Looks like there is a longer history to that (see Patch #2 for details), and fixing it to work the way it was intended is not really possible. We would e.g. have to take the mem_hotplug_lock in device/base/core.c, which sounds wrong. Summary: We had a lock inversion on mem_hotplug_lock and device_lock(). More details can be found in patch 3 and patch 6. I propose the general rules (documentation added in patch 6): 1. add_memory/add_memory_resource() must only be called with device_hotplug_lock. 2. remove_memory() must only be called with device_hotplug_lock. This is already documented and holds for all callers. 3. device_online()/device_offline() must only be called with device_hotplug_lock. This is already documented and true for now in core code. Other callers (related to memory hotplug) have to be fixed up. 4. mem_hotplug_lock is taken inside of add_memory/remove_memory/ online_pages/offline_pages. To me, this looks way cleaner than what we have right now (and easier to verify). And looking at the documentation of remove_memory, using lock_device_hotplug also for add_memory() feels natural. This patch (of 6): remove_memory() is exported right now but requires the device_hotplug_lock, which is not exported. So let's provide a variant that takes the lock and only export that one. The lock is already held in arch/powerpc/platforms/pseries/hotplug-memory.c drivers/acpi/acpi_memhotplug.c arch/powerpc/platforms/powernv/memtrace.c Apart from that, there are not other users in the tree. Link: http://lkml.kernel.org/r/20180925091457.28651-2-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Pavel Tatashin <pavel.tatashin@microsoft.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Rashmica Gupta <rashmica.g@gmail.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: Len Brown <lenb@kernel.org> Cc: Rashmica Gupta <rashmica.g@gmail.com> Cc: Michael Neuling <mikey@neuling.org> Cc: Balbir Singh <bsingharora@gmail.com> Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com> Cc: John Allen <jallen@linux.vnet.ibm.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: YASUAKI ISHIMATSU <yasu.isimatu@gmail.com> Cc: Mathieu Malaterre <malat@debian.org> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Juergen Gross <jgross@suse.com> Cc: Kate Stewart <kstewart@linuxfoundation.org> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Philippe Ombredanne <pombredanne@nexb.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-07-08ACPI: Remove FSF mailing addressesJarkko Nikula
There is no need to carry potentially outdated Free Software Foundation mailing address in file headers since the COPYING file includes it. Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2015-01-26ACPICA: Resources: Provide common part for struct acpi_resource_address ↵Lv Zheng
structures. struct acpi_resource_address and struct acpi_resource_extended_address64 share substracts just at different offsets. To unify the parsing functions, OSPMs like Linux need a new ACPI_ADDRESS64_ATTRIBUTE as their substructs, so they can extract the shared data. This patch also synchronizes the structure changes to the Linux kernel. The usages are searched by matching the following keywords: 1. acpi_resource_address 2. acpi_resource_extended_address 3. ACPI_RESOURCE_TYPE_ADDRESS 4. ACPI_RESOURCE_TYPE_EXTENDED_ADDRESS And we found and fixed the usages in the following files: arch/ia64/kernel/acpi-ext.c arch/ia64/pci/pci.c arch/x86/pci/acpi.c arch/x86/pci/mmconfig-shared.c drivers/xen/xen-acpi-memhotplug.c drivers/acpi/acpi_memhotplug.c drivers/acpi/pci_root.c drivers/acpi/resource.c drivers/char/hpet.c drivers/pnp/pnpacpi/rsparser.c drivers/hv/vmbus_drv.c Build tests are passed with defconfig/allnoconfig/allyesconfig and defconfig+CONFIG_ACPI=n. Original-by: Thomas Gleixner <tglx@linutronix.de> Original-by: Jiang Liu <jiang.liu@linux.intel.com> Signed-off-by: Lv Zheng <lv.zheng@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2014-05-30ACPI / scan: always register memory hotplug scan handlerRafael J. Wysocki
Prevent platform devices from being created for ACPI memory device objects if CONFIG_ACPI_HOTPLUG_MEMORY is unset by compiling out the memory hotplug scan handler's callbacks only in that case and still compiling its device ID list in and registering the scan handler in either case. Also unset the memory hotplug scan handler's .attach() callback if acpi_no_memhotplug is set, but still register the scan handler to avoid creating platform devices for ACPI memory devices in that case too. This change is based on a prototype from Zhang Rui. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2014-01-16ACPI / memhotplug: add parameter to disable memory hotplugPrarit Bhargava
When booting a kexec/kdump kernel on a system that has specific memory hotplug regions the boot will fail with warnings like: swapper/0: page allocation failure: order:9, mode:0x84d0 CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.10.0-65.el7.x86_64 #1 Hardware name: QCI QSSC-S4R/QSSC-S4R, BIOS QSSC-S4R.QCI.01.00.S013.032920111005 03/29/2011 0000000000000000 ffff8800341bd8c8 ffffffff815bcc67 ffff8800341bd950 ffffffff8113b1a0 ffff880036339b00 0000000000000009 00000000000084d0 ffff8800341bd950 ffffffff815b87ee 0000000000000000 0000000000000200 Call Trace: [<ffffffff815bcc67>] dump_stack+0x19/0x1b [<ffffffff8113b1a0>] warn_alloc_failed+0xf0/0x160 [<ffffffff815b87ee>] ? __alloc_pages_direct_compact+0xac/0x196 [<ffffffff8113f14f>] __alloc_pages_nodemask+0x7ff/0xa00 [<ffffffff815b417c>] vmemmap_alloc_block+0x62/0xba [<ffffffff815b41e9>] vmemmap_alloc_block_buf+0x15/0x3b [<ffffffff815b1ff6>] vmemmap_populate+0xb4/0x21b [<ffffffff815b461d>] sparse_mem_map_populate+0x27/0x35 [<ffffffff815b400f>] sparse_add_one_section+0x7a/0x185 [<ffffffff815a1e9f>] __add_pages+0xaf/0x240 [<ffffffff81047359>] arch_add_memory+0x59/0xd0 [<ffffffff815a21d9>] add_memory+0xb9/0x1b0 [<ffffffff81333b9c>] acpi_memory_device_add+0x18d/0x26d [<ffffffff81309a01>] acpi_bus_device_attach+0x7d/0xcd [<ffffffff8132379d>] acpi_ns_walk_namespace+0xc8/0x17f [<ffffffff81309984>] ? acpi_bus_type_and_status+0x90/0x90 [<ffffffff81309984>] ? acpi_bus_type_and_status+0x90/0x90 [<ffffffff81323c8c>] acpi_walk_namespace+0x95/0xc5 [<ffffffff8130a6d6>] acpi_bus_scan+0x8b/0x9d [<ffffffff81a2019a>] acpi_scan_init+0x63/0x160 [<ffffffff81a1ffb5>] acpi_init+0x25d/0x2a6 [<ffffffff81a1fd58>] ? acpi_sleep_proc_init+0x2a/0x2a [<ffffffff810020e2>] do_one_initcall+0xe2/0x190 [<ffffffff819e20c4>] kernel_init_freeable+0x17c/0x207 [<ffffffff819e18d0>] ? do_early_param+0x88/0x88 [<ffffffff8159fea0>] ? rest_init+0x80/0x80 [<ffffffff8159feae>] kernel_init+0xe/0x180 [<ffffffff815cca2c>] ret_from_fork+0x7c/0xb0 [<ffffffff8159fea0>] ? rest_init+0x80/0x80 Mem-Info: Node 0 DMA per-cpu: CPU 0: hi: 0, btch: 1 usd: 0 Node 0 DMA32 per-cpu: CPU 0: hi: 42, btch: 7 usd: 0 active_anon:0 inactive_anon:0 isolated_anon:0 active_file:0 inactive_file:0 isolated_file:0 unevictable:0 dirty:0 writeback:0 unstable:0 free:872 slab_reclaimable:13 slab_unreclaimable:1880 mapped:0 shmem:0 pagetables:0 bounce:0 free_cma:0 because the system has run out of memory at boot time. This occurs because of the following sequence in the boot: Main kernel boots and sets E820 map. The second kernel is booted with a map generated by the kdump service using memmap= and memmap=exactmap. These parameters are added to the kernel parameters of the kexec/kdump kernel. The kexec/kdump kernel has limited memory resources so as not to severely impact the main kernel. The system then panics and the kdump/kexec kernel boots (which is a completely new kernel boot). During this boot ACPI is initialized and the kernel (as can be seen above) traverses the ACPI namespace and finds an entry for a memory device to be hotadded. ie) [<ffffffff815a1e9f>] __add_pages+0xaf/0x240 [<ffffffff81047359>] arch_add_memory+0x59/0xd0 [<ffffffff815a21d9>] add_memory+0xb9/0x1b0 [<ffffffff81333b9c>] acpi_memory_device_add+0x18d/0x26d [<ffffffff81309a01>] acpi_bus_device_attach+0x7d/0xcd [<ffffffff8132379d>] acpi_ns_walk_namespace+0xc8/0x17f [<ffffffff81309984>] ? acpi_bus_type_and_status+0x90/0x90 [<ffffffff81309984>] ? acpi_bus_type_and_status+0x90/0x90 [<ffffffff81323c8c>] acpi_walk_namespace+0x95/0xc5 [<ffffffff8130a6d6>] acpi_bus_scan+0x8b/0x9d [<ffffffff81a2019a>] acpi_scan_init+0x63/0x160 [<ffffffff81a1ffb5>] acpi_init+0x25d/0x2a6 At this point the kernel adds page table information and the the kexec/kdump kernel runs out of memory. This can also be reproduced by using the memmap=exactmap and mem=X parameters on the main kernel and booting. This patchset resolves the problem by adding a kernel parameter, acpi_no_memhotplug, to disable ACPI memory hotplug. Signed-off-by: Prarit Bhargava <prarit@redhat.com> Acked-by: Vivek Goyal <vgoyal@redhat.com> Acked-by: Toshi Kani <toshi.kani@hp.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-12-07ACPI / bind: Pass struct acpi_device pointer to acpi_bind_one()Rafael J. Wysocki
There is no reason to pass an ACPI handle to acpi_bind_one() instead of a struct acpi_device pointer to the target device object, so modify that function to take a struct acpi_device pointer as its second argument and update all code depending on it accordingly. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Lan Tianyu <tianyu.lan@intel.com> # for USB/ACPI
2013-10-28Merge branch 'acpi-hotplug'Rafael J. Wysocki
* acpi-hotplug: ACPI / memhotplug: Use defined marco METHOD_NAME__STA ACPI / hotplug: Use kobject_init_and_add() instead of _init() and _add() ACPI / hotplug: Don't set kobject parent pointer explicitly ACPI / hotplug: Set kobject name via kobject_add(), not kobject_set_name() hotplug, powerpc, x86: Remove cpu_hotplug_driver_lock() hotplug / x86: Disable ARCH_CPU_PROBE_RELEASE on x86 hotplug / x86: Add hotplug lock to missing places hotplug / x86: Fix online state in cpu0 debug interface
2013-10-10ACPI / memhotplug: Use defined marco METHOD_NAME__STAZhang Yanfei
We already have predefined marco for method name "_STA', so using the marco instead of directly using the string. Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-09-24ACPI / mm: use NUMA_NO_NODEJianguo Wu
Use more appropriate NUMA_NO_NODE instead of -1 Signed-off-by: Jianguo Wu <wujianguo@huawei.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-07-15ACPI / memhotplug: Fix a stale pointer in error pathToshi Kani
device->driver_data needs to be cleared when releasing its data, mem_device, in an error path of acpi_memory_device_add(). The function evaluates the _CRS of memory device objects, and fails when it gets an unexpected resource or cannot allocate memory. A kernel crash or data corruption may occur when the kernel accesses the stale pointer. Signed-off-by: Toshi Kani <toshi.kani@hp.com> Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: 2.6.32+ <stable@vger.kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-06-01Memory hotplug / ACPI: Simplify memory removalRafael J. Wysocki
Now that the memory offlining should be taken care of by the companion device offlining code in acpi_scan_hot_remove(), the ACPI memory hotplug driver doesn't need to offline it in remove_memory() any more. Moreover, since the return value of remove_memory() is not used, it's better to make it be a void function and trigger a BUG() if the memory scheduled for removal is not offline. Change the code in accordance with the above observations. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Toshi Kani <toshi.kani@hp.com>
2013-05-12ACPI / memhotplug: Bind removable memory blocks to ACPI device nodesRafael J. Wysocki
During ACPI memory hotplug configuration bind memory blocks residing in modules removable through the standard ACPI mechanism to struct acpi_device objects associated with ACPI namespace objects representing those modules. Accordingly, unbind those memory blocks from the struct acpi_device objects when the memory modules in question are being removed. When "offline" operation for devices representing memory blocks is introduced, this will allow the ACPI core's device hot-remove code to use it to carry out remove_memory() for those memory blocks and check the results of that before it actually removes the modules holding them from the system. Since walk_memory_range() is used for accessing all memory blocks corresponding to a given ACPI namespace object, it is exported from memory_hotplug.c so that the code in acpi_memhotplug.c can use it. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Tested-by: Vasilis Liaskovitis <vasilis.liaskovitis@profitbricks.com> Reviewed-by: Toshi Kani <toshi.kani@hp.com>
2013-03-25ACPI / memhotplug: Remove info->failed bitYasuaki Ishimatsu
acpi_memory_info has enabled bit and failed bit for controlling memory hotplug. But we don't need to keep both bits. The patch removes acpi_memory_info->failed bit. Signed-off-by: yasuaki ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Acked-by: Toshi Kani <toshi.kani@hp.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-03-25ACPI / memhotplug: set info->enabled for memory present at boot timeYasuaki Ishimatsu
At http://marc.info/?l=linux-acpi&m=135769405622667&w=2 thread, Toshi Kani mentioned as follows: "I have a question about the change you made in commit 65479472 in acpi_memhotplug.c. This change seems to require that acpi_memory_enable_device() calls add_memory() to add all memory ranges represented by memory device objects at boot-time, and keep the results be used for hot-remove. If I understand it right, this add_memory() call fails with EEXIST at boot-time since all memory ranges should have been added from EFI memory table (or e820) already. This results all memory ranges be marked as ! enabled & !failed. I think this means that we cannot hot-delete any memory ranges presented at boot-time since acpi_memory_remove_memory() only calls remove_memory() when the enabled flag is set. Is that correct?" Above mention is correct. Thus even if memory device supports hotplug, memory presented at boot-time cannot be hot removed since the memory device's acpi_memory_info->enabled is always 0. This patch changes to set 1 to "acpi_memory_info->enabled" of memory device presented at boot-time for hot removing the memory device. Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Acked-by: Toshi Kani <toshi.kani@hp.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-03-04ACPI / scan: Make memory hotplug driver use struct acpi_scan_handlerRafael J. Wysocki
Make the ACPI memory hotplug driver use struct acpi_scan_handler for representing the object used to set up ACPI memory hotplug functionality and to remove hotplug memory ranges and data structures used by the driver before unregistering ACPI device nodes representing memory. Register the new struct acpi_scan_handler object with the help of acpi_scan_add_handler_with_hotplug() to allow user space to manipulate the attributes of the memory hotplug profile. This results in a significant reduction of the drvier's code size and removes some ACPI hotplug code duplication. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Toshi Kani <toshi.kani@hp.com> Tested-by: Toshi Kani <toshi.kani@hp.com>
2013-02-23memory-hotplug: remove sysfs file of nodeTang Chen
Introduce a new function try_offline_node() to remove sysfs file of node when all memory sections of this node are removed. If some memory sections of this node are not removed, this function does nothing. Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Tang Chen <tangchen@cn.fujitsu.com> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Jianguo Wu <wujianguo@huawei.com> Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Wu Jianguo <wujianguo@huawei.com> Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-13ACPI / hotplug: Fix concurrency issues and memory leaksRafael J. Wysocki
This changeset is aimed at fixing a few different but related problems in the ACPI hotplug infrastructure. First of all, since notify handlers may be run in parallel with acpi_bus_scan(), acpi_bus_trim() and acpi_bus_hot_remove_device() and some of them are installed for ACPI handles that have no struct acpi_device objects attached (i.e. before those objects are created), those notify handlers have to take acpi_scan_lock to prevent races from taking place (e.g. a struct acpi_device is found to be present for the given ACPI handle, but right after that it is removed by acpi_bus_trim() running in parallel to the given notify handler). Moreover, since some of them call acpi_bus_scan() and acpi_bus_trim(), this leads to the conclusion that acpi_scan_lock should be acquired by the callers of these two funtions rather by these functions themselves. For these reasons, make all notify handlers that can handle device addition and eject events take acpi_scan_lock and remove the acpi_scan_lock locking from acpi_bus_scan() and acpi_bus_trim(). Accordingly, update all of their users to make sure that they are always called under acpi_scan_lock. Furthermore, since eject operations are carried out asynchronously with respect to the notify events that trigger them, with the help of acpi_bus_hot_remove_device(), even if notify handlers take the ACPI scan lock, it still is possible that, for example, acpi_bus_trim() will run between acpi_bus_hot_remove_device() and the notify handler that scheduled its execution and that acpi_bus_trim() will remove the device node passed to acpi_bus_hot_remove_device() for ejection. In that case, the struct acpi_device object obtained by acpi_bus_hot_remove_device() will be invalid and not-so-funny things will ensue. To protect agaist that, make the users of acpi_bus_hot_remove_device() run get_device() on ACPI device node objects that are about to be passed to it and make acpi_bus_hot_remove_device() run put_device() on them and check if their ACPI handles are not NULL (make acpi_device_unregister() clear the device nodes' ACPI handles for that check to work). Finally, observe that acpi_os_hotplug_execute() actually can fail, in which case its caller ought to free memory allocated for the context object to prevent leaks from happening. It also needs to run put_device() on the device node that it ran get_device() on previously in that case. Modify the code accordingly. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Yinghai Lu <yinghai@kernel.org>
2013-01-26ACPI: Remove useless type argument of driver .remove() operationRafael J. Wysocki
The second argument of ACPI driver .remove() operation is only used by the ACPI processor driver and the value passed to that driver through it is always available from the given struct acpi_device object's removal_type field. For this reason, the second ACPI driver .remove() argument is in fact useless, so drop it. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Jiang Liu <jiang.liu@huawei.com> Acked-by: Toshi Kani <toshi.kani@hp.com> Acked-by: Yinghai Lu <yinghai@kernel.org>
2013-01-26Merge branch 'acpi-scan' into acpi-cleanupRafael J. Wysocki
The following commits depend on the 'acpi-scan' material.
2013-01-19ACPI / scan: Drop acpi_bus_add() and use acpi_bus_scan() insteadRafael J. Wysocki
The only difference between acpi_bus_scan() and acpi_bus_add() is the invocation of acpi_update_all_gpes() in the latter which in fact is unnecessary, because acpi_update_all_gpes() has already been called by acpi_scan_init() and the way it is implemented guarantees the next invocations of it to do nothing. For this reason, drop acpi_bus_add() and make all its callers use acpi_bus_scan() directly instead of it. Additionally, rearrange the code in acpi_scan_init() slightly to improve the visibility of the acpi_update_all_gpes() call in there. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Yinghai Lu <yinghai@kernel.org>
2013-01-15ACPI: update ej_event interface to take acpi_deviceYinghai Lu
Should use acpi_device pointer directly instead of use handle and get the device pointer again later. Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-01-03ACPI / memhotplug: remove redundant logic of acpi memory hotaddLiu Jinsong
When memory hotadd, acpi_memory_enable_device has already been done at drv->ops.add (acpi_memory_device_add), no need to do it again at notify callback. At acpi_memory_enable_device, acpi_memory_get_device_resources is also a redundant action, since it has been done at drv->ops.add. Signed-off-by: Liu Jinsong <jinsong.liu@intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-01-03ACPI: Make acpi_bus_scan() and acpi_bus_add() take only one argumentRafael J. Wysocki
The callers of acpi_bus_add() usually assume that if it has succeeded, then a struct acpi_device object has been attached to the handle passed as the first argument. Unfortunately, however, this assumption is wrong, because acpi_bus_scan(), and acpi_bus_add() too as a result, may return a pointer to a different struct acpi_device object on success (it may be an object corresponding to one of the descendant ACPI nodes in the namespace scope below that handle). For this reason, the callers of acpi_bus_add() who care about whether or not a struct acpi_device object has been created for its first argument need to check that using acpi_bus_get_device() anyway, so the second argument of acpi_bus_add() is not really useful for them. The same observation applies to acpi_bus_scan() executed directly from acpi_scan_init(). Therefore modify the relevant callers of acpi_bus_add() to check the existence of the struct acpi_device in question with the help of acpi_bus_get_device() and drop the no longer necessary second argument of acpi_bus_add(). Accordingly, modify acpi_scan_init() to use acpi_bus_get_device() to get acpi_root and drop the no longer needed second argument of acpi_bus_scan(). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Yinghai Lu <yinghai@kernel.org> Acked-by: Toshi Kani <toshi.kani@hp.com>
2013-01-03ACPI: Remove the arguments of acpi_bus_add() that are not usedRafael J. Wysocki
Notice that acpi_bus_add() uses only 2 of its 4 arguments and redefine its header to match the body. Update all of its callers as necessary and observe that this leads to quite a number of removed lines of code (Linus will like that). Add a kerneldoc comment documenting acpi_bus_add() and wonder how its callers make wrong assumptions about the second argument (make note to self to take care of that later). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Yinghai Lu <yinghai@kernel.org> Acked-by: Toshi Kani <toshi.kani@hp.com>
2012-11-21ACPI: Update Memory hotplug error messagesToshi Kani
Updated Memory hotplug error messages with acpi_handle_<level>(), dev_<level>() and pr_<level>(). Added missing "\n". Signed-off-by: Toshi Kani <toshi.kani@hp.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-11-16ACPI / memhotplug: bind the memory device when the driver is being loadedWen Congyang
We had introduced acpi_hotmem_initialized to avoid strange add_memory fail message. But the memory device may not be used by the kernel, and the device should be bound when the driver is being loaded. Remove acpi_hotmem_initialized to allow that the device can be bound when the driver is being loaded. Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-11-16ACPI / memhotplug: don't allow to eject the memory device if it is being usedWen Congyang
We eject the memory device even if it is in use. It is very dangerous, and it will cause the kernel to be panicked. Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-11-16ACPI / memhotplug: free memory device if acpi_memory_enable_device() failedWen Congyang
If acpi_memory_enable_device() fails, acpi_memory_enable_device() will return a non-zero value, which means we fail to bind the memory device to this driver. So we should free memory device before acpi_memory_device_add() returns. Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-11-16ACPI / memhotplug: fix memory leak when memory device is unbound from ↵Wen Congyang
acpi_memhotplug We allocate memory to store acpi_memory_info, so we should free it before freeing mem_device. Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-11-16ACPI / memhotplug: deal with eject request in hotplug queueWen Congyang
The memory device can be removed by 2 ways: 1. send eject request by SCI 2. echo 1 >/sys/bus/pci/devices/PNP0C80:XX/eject We handle the 1st case in the module acpi_memhotplug, and handle the 2nd case in ACPI eject notification. This 2 events may happen at the same time, so we may touch acpi_memory_device.res_list at the same time. This patch reimplements memory-hotremove support through an ACPI eject notification. Now the memory device is offlined and hotremoved only in the function acpi_memory_device_remove() which is protected by device_lock(). Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Reviewed-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Reviewed-by: Toshi Kani <toshi.kani@hp.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-11-16ACPI / memory-hotplug: add memory offline code to acpi_memory_device_remove()Yasuaki Ishimatsu
The memory device can be removed by 2 ways: 1. send eject request by SCI 2. echo 1 >/sys/bus/pci/devices/PNP0C80:XX/eject In the 1st case, acpi_memory_disable_device() will be called. In the 2nd case, acpi_memory_device_remove() will be called. acpi_memory_device_remove() will also be called when we unbind the memory device from the driver acpi_memhotplug or a driver initialization fails. acpi_memory_disable_device() has already implemented a code which offlines memory and releases acpi_memory_info struct. But acpi_memory_device_remove() has not implemented it yet. So the patch move offlining memory and releasing acpi_memory_info struct codes to a new function acpi_memory_remove_memory(). And it is used by both acpi_memory_device_remove() and acpi_memory_disable_device(). Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-11-15ACPI / memory-hotplug: call acpi_bus_trim() to remove memory deviceWen Congyang
The memory device has been ejected and powoffed, so we can call acpi_bus_trim() to remove the memory device from acpi bus. Signed-off-by: Wen Congyang <wency@cn.fujitsu.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2012-06-04ACPI: Add _OST support for ACPI memory hotplugToshi Kani
Changed acpi_memory_device_notify() to call ACPI _OST method when ACPI memory hotplug operation has completed. Signed-off-by: Toshi Kani <toshi.kani@hp.com> Signed-off-by: Len Brown <len.brown@intel.com>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2009-11-24ACPICA: Add post-order callback to acpi_walk_namespaceLin Ming
The existing interface only has a pre-order callback. This change adds an additional parameter for a post-order callback which will be more useful for bus scans. ACPICA BZ 779. Also update the external calls to acpi_walk_namespace. http://www.acpica.org/bugzilla/show_bug.cgi?id=779 Signed-off-by: Lin Ming <ming.m.lin@intel.com> Signed-off-by: Bob Moore <robert.moore@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
2009-09-19Merge branch 'bjorn-start-stop-2.6.32' into releaseLen Brown
2009-08-27ACPICA: Major update for acpi_get_object_info external interfaceBob Moore
Completed a major update for the acpi_get_object_info external interface. Changes include: - Support for variable, unlimited length HID, UID, and CID strings - Support Processor objects the same as Devices (HID,UID,CID,ADR,STA, etc.) - Call the _SxW power methods on behalf of a device object - Determine if a device is a PCI root bridge - Change the ACPI_BUFFER parameter to ACPI_DEVICE_INFO. These changes will require an update to all callers of this interface. See the ACPICA Programmer Reference for details. Also, update all invocations of acpi_get_object_info interface Signed-off-by: Bob Moore <robert.moore@intel.com> Signed-off-by: Lin Ming <ming.m.lin@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
2009-08-02ACPI: Ingore the memory block with zero block size in course of memory hotplugZhao Yakui
If the memory block size is zero, ignore it and don't do the memory hotplug flowchart. Otherwise it will complain the following warning message: >System RAM resource 0 - ffffffffffffffff cannot be added Signed-off-by: Zhao Yakui <yakui.zhao@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
2009-08-02ACPI: Don't treat generic error as ACPI error code in acpi memory hotplug driverZhao Yakui
Don't treat the generic error as ACPI error code. Otherwise when the generic code is returned, it will complain the following warning messag: >ACPI Exception (acpi_memhotplug-0171): UNKNOWN_STATUS_CODE, Cannot get acpi bus device [20080609] >ACPI: Cannot find driver data > ACPI Error (utglobal-0127): Unknown exception code: 0xFFFFFFED [20080609] > Pid: 85, comm: kacpi_notify Not tainted 2.6.27.19-5-default #1 Call Trace: [<ffffffff8020da29>] show_trace_log_lvl+0x41/0x58 [<ffffffff8049a3da>] dump_stack+0x69/0x6f ..... At the same time when the generic error code is returned, the ACPI_EXCEPTION is replaced by the printk. Signed-off-by: Zhao Yakui <yakui.zhao@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
2009-06-25ACPI: memory hotplug: remove .start() methodBjorn Helgaas
This patch folds the .start() method into .add(). The .start() method is called in two paths: boot-time device enumeration and run-time node addition, currently via container_device_add(). In both cases, .start() is called immediately after .add(), so there's no reason to make them separate methods. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Reviewed-by: Alex Chiang <achiang@hp.com> CC: Yasunori Goto <y-goto@jp.fujitsu.com> CC: Dave Hansen <haveblue@us.ibm.com> Signed-off-by: Len Brown <len.brown@intel.com>
2009-01-06trivial: Fix misspelling of "firmware" in acpi_memhotplug.cNick Andrew
Fix misspelling of "firmware" in acpi_memhotplug.c It's spelled "firmware". Signed-off-by: Nick Andrew <nick@nick-andrew.net> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2008-11-07ACPI: consolidate ACPI_*_COMPONENT definitions in acpi_drivers.hBjorn Helgaas
Move all the component definitions for drivers to a single shared place, include/acpi/acpi_drivers.h. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Len Brown <len.brown@intel.com>
2008-10-22Merge branch 'ull' into testLen Brown
Conflicts: drivers/acpi/bay.c drivers/acpi/dock.c drivers/ata/libata-acpi.c Signed-off-by: Len Brown <len.brown@intel.com>
2008-10-22Merge branch 'misc' into testLen Brown
2008-10-22ACPI: replace ACPI_DEBUG_PRINT((ACPI_DB_ERROR, ...) with printkLin Ming
ACPI_DB_ERROR and ACPI_DB_WARN were removed from ACPICA core. So replace ACPI_DEBUG_PRINT((ACPI_DB_ERROR, ...) with printk(KERN_ERR PREFIX ...) and ACPI_DEBUG_PRINT((ACPI_DB_WARN, ...) with printk(KERN_WARNING PREFIX ...) We do not use ACPI_ERROR/ACPI_WARNING since they're not exported, see ------------------------------------------------------------- commit 6468463abd7051fcc29f3ee7c931f9bbbb26f5a4 Author: Len Brown <len.brown@intel.com> Date: Mon Jun 26 23:41:38 2006 -0400 ACPI: un-export ACPI_ERROR() -- use printk(KERN_ERR...) Signed-off-by: Len Brown <len.brown@intel.com> ------------------------------------------------------------- Signed-off-by: Lin Ming <ming.m.lin@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
2008-10-11ACPI: Change acpi_evaluate_integer to support 64-bit on 32-bit kernelsMatthew Wilcox
As of version 2.0, ACPI can return 64-bit integers. The current acpi_evaluate_integer only supports 64-bit integers on 64-bit platforms. Change the argument to take a pointer to an acpi_integer so we support 64-bit integers on all platforms. lenb: replaced use of "acpi_integer" with "unsigned long long" lenb: fixed bug in acpi_thermal_trips_update() Signed-off-by: Matthew Wilcox <willy@linux.intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
2008-10-10ACPI: catch calls of acpi_driver_data on pointer of wrong typePavel Machek
Catch attempts to use of acpi_driver_data on pointers of wrong type. akpm: rewritten to use proper C typechecking and remove the "function"-used-as-lvalue thing. Signed-off-by: Pavel Machek <pavel@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Len Brown <len.brown@intel.com>