Commits
Yasuaki Ishimatsu committed 5255e0a79fc
x86/mm/hotplug: Pass sync_global_pgds() a correct argument in remove_pagetable() When hot-adding memory after hot-removing memory, following call traces are shown: kernel BUG at arch/x86/mm/init_64.c:206! ... [<ffffffff815e0c80>] kernel_physical_mapping_init+0x1b2/0x1d2 [<ffffffff815ced94>] init_memory_mapping+0x1d4/0x380 [<ffffffff8104aebd>] arch_add_memory+0x3d/0xd0 [<ffffffff815d03d9>] add_memory+0xb9/0x1b0 [<ffffffff81352415>] acpi_memory_device_add+0x1af/0x28e [<ffffffff81325dc4>] acpi_bus_device_attach+0x8c/0xf0 [<ffffffff813413b9>] acpi_ns_walk_namespace+0xc8/0x17f [<ffffffff81325d38>] ? acpi_bus_type_and_status+0xb7/0xb7 [<ffffffff81325d38>] ? acpi_bus_type_and_status+0xb7/0xb7 [<ffffffff813418ed>] acpi_walk_namespace+0x95/0xc5 [<ffffffff81326b4c>] acpi_bus_scan+0x9a/0xc2 [<ffffffff81326bff>] acpi_scan_bus_device_check+0x8b/0x12e [<ffffffff81326cb5>] acpi_scan_device_check+0x13/0x15 [<ffffffff81320122>] acpi_os_execute_deferred+0x25/0x32 [<ffffffff8107e02b>] process_one_work+0x17b/0x460 [<ffffffff8107edfb>] worker_thread+0x11b/0x400 [<ffffffff8107ece0>] ? rescuer_thread+0x400/0x400 [<ffffffff81085aef>] kthread+0xcf/0xe0 [<ffffffff81085a20>] ? kthread_create_on_node+0x140/0x140 [<ffffffff815fc76c>] ret_from_fork+0x7c/0xb0 [<ffffffff81085a20>] ? kthread_create_on_node+0x140/0x140 The patch-set fixes the issue. This patch (of 2): remove_pagetable() gets start argument and passes the argument to sync_global_pgds(). In this case, the argument must not be modified. If the argument is modified and passed to sync_global_pgds(), sync_global_pgds() does not correctly synchronize PGD to PGD entries of all processes MM since synchronized range of memory [start, end] is wrong. Unfortunately the start argument is modified in remove_pagetable(). So this patch fixes the issue. Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com> Acked-by: Toshi Kani <toshi.kani@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Tang Chen <tangchen@cn.fujitsu.com> Cc: Gu Zheng <guz.fnst@cn.fujitsu.com> Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@kernel.org>