From 6e52e4b6cf50c26af2ec20b4b527fc7046892a20 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Tue, 30 Apr 2019 21:51:21 -0700 Subject: libnvdimm/namespace: Fix label tracking error commit c4703ce11c23423d4b46e3d59aef7979814fd608 upstream. Users have reported intermittent occurrences of DIMM initialization failures due to duplicate allocations of address capacity detected in the labels, or errors of the form below, both have the same root cause. nd namespace1.4: failed to track label: 0 WARNING: CPU: 17 PID: 1381 at drivers/nvdimm/label.c:863 RIP: 0010:__pmem_label_update+0x56c/0x590 [libnvdimm] Call Trace: ? nd_pmem_namespace_label_update+0xd6/0x160 [libnvdimm] nd_pmem_namespace_label_update+0xd6/0x160 [libnvdimm] uuid_store+0x17e/0x190 [libnvdimm] kernfs_fop_write+0xf0/0x1a0 vfs_write+0xb7/0x1b0 ksys_write+0x57/0xd0 do_syscall_64+0x60/0x210 Unfortunately those reports were typically with a busy parallel namespace creation / destruction loop making it difficult to see the components of the bug. However, Jane provided a simple reproducer using the work-in-progress sub-section implementation. When ndctl is reconfiguring a namespace it may take an existing defunct / disabled namespace and reconfigure it with a new uuid and other parameters. Critically namespace_update_uuid() takes existing address resources and renames them for the new namespace to use / reconfigure as it sees fit. The bug is that this rename only happens in the resource tracking tree. Existing labels with the old uuid are not reaped leading to a scenario where multiple active labels reference the same span of address range. Teach namespace_update_uuid() to flag any references to the old uuid for reaping at the next label update attempt. Cc: Fixes: bf9bccc14c05 ("libnvdimm: pmem label sets and namespace instantiation") Link: https://github.com/pmem/ndctl/issues/91 Reported-by: Jane Chu Reported-by: Jeff Moyer Reported-by: Erwin Tsaur Cc: Johannes Thumshirn Signed-off-by: Dan Williams Signed-off-by: Greg Kroah-Hartman --- drivers/nvdimm/nd.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'drivers/nvdimm/nd.h') diff --git a/drivers/nvdimm/nd.h b/drivers/nvdimm/nd.h index 379bf4305e61..e8d73db13ee1 100644 --- a/drivers/nvdimm/nd.h +++ b/drivers/nvdimm/nd.h @@ -113,8 +113,12 @@ struct nd_percpu_lane { spinlock_t lock; }; +enum nd_label_flags { + ND_LABEL_REAP, +}; struct nd_label_ent { struct list_head list; + unsigned long flags; struct nd_namespace_label *label; }; -- cgit v1.2.3