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authorPrarit Bhargava <prarit@redhat.com>2014-01-14 14:21:13 -0500
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2014-01-16 01:43:49 +0100
commit00159a2013269bc0a617de885e4b921349192bd0 (patch)
tree7461865e3097d9a0aeadf65e81d6f2d813646644 /drivers/acpi/acpi_memhotplug.c
parentc713cd7f2d799c50a0721bf51d178ea9567215dd (diff)
ACPI / memhotplug: add parameter to disable memory hotplug
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>
Diffstat (limited to 'drivers/acpi/acpi_memhotplug.c')
-rw-r--r--drivers/acpi/acpi_memhotplug.c12
1 files changed, 12 insertions, 0 deletions
diff --git a/drivers/acpi/acpi_memhotplug.c b/drivers/acpi/acpi_memhotplug.c
index 9aeacdfca410..b67be85ff0fc 100644
--- a/drivers/acpi/acpi_memhotplug.c
+++ b/drivers/acpi/acpi_memhotplug.c
@@ -360,7 +360,19 @@ static void acpi_memory_device_remove(struct acpi_device *device)
acpi_memory_device_free(mem_device);
}
+static bool __initdata acpi_no_memhotplug;
+
void __init acpi_memory_hotplug_init(void)
{
+ if (acpi_no_memhotplug)
+ return;
+
acpi_scan_add_handler_with_hotplug(&memory_device_handler, "memory");
}
+
+static int __init disable_acpi_memory_hotplug(char *str)
+{
+ acpi_no_memhotplug = true;
+ return 1;
+}
+__setup("acpi_no_memhotplug", disable_acpi_memory_hotplug);