On Mon, Jul 2, 2018 at 12:48 PM Pavel Tatashin <pasha.tatashin@xxxxxxxxxx> wrote: > > On Mon, Jul 2, 2018 at 11:43 AM <osalvador@xxxxxxxxxxxxxxxxxx> wrote: > > > > From: Oscar Salvador <osalvador@xxxxxxx> > > > > sparse_init_one_section() is being called from two sites: > > sparse_init() and sparse_add_one_section(). > > The former calls it from a for_each_present_section_nr() loop, > > and the latter marks the section as present before calling it. > > This means that when sparse_init_one_section() gets called, we already know > > that the section is present. > > So there is no point to double check that in the function. > > > > This removes the check and makes the function void. > > > > Signed-off-by: Oscar Salvador <osalvador@xxxxxxx> > > Thank you Oscar. > > Reviewed-by: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx> It looks like this change breaks "fsdax" mode namespaces in next-20180705. The offending commit is: commit 054620849110 ("mm/sparse.c: make sparse_init_one_section void and remove check") Here is the stack trace I get when converting a raw mode namespace to fsdax mode, and from then on during each reboot as the namespace is being initialized: [ 6.067166] BUG: unable to handle kernel paging request at ffffea0005000080 [ 6.068084] PGD 13ffdd067 P4D 13ffdd067 PUD 13ffdc067 PMD 0 [ 6.068771] Oops: 0002 [#1] PREEMPT SMP PTI [ 6.069262] CPU: 11 PID: 180 Comm: kworker/u24:2 Not tainted 4.18.0-rc3-00193-g054620849110 #1 [ 6.070440] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.1-0-g0551a4be2c-prebuilt.qemu-project.org 04/01/2014 [ 6.071689] Workqueue: events_unbound async_run_entry_fn [ 6.072261] RIP: 0010:memmap_init_zone+0x154/0x1cf [ 6.072882] Code: 48 89 c3 48 c1 eb 0c e9 82 00 00 00 48 89 da 48 b8 00 00 00 00 00 ea ff ff b9 10 00 00 00 48 c1 e2 06 48 01 c2 31 c0 48 89 d7 <f3> ab 48 b8 ff ff ff ff ff ff 7f 00 48 23 45 c0 c7 42 34 01 00 00 [ 6.075396] RSP: 0018:ffffc900024bfa70 EFLAGS: 00010246 [ 6.076052] RAX: 0000000000000000 RBX: 0000000000140002 RCX: 0000000000000010 [ 6.076845] RDX: ffffea0005000080 RSI: 0000000000000000 RDI: ffffea0005000080 [ 6.077604] RBP: ffffc900024bfab0 R08: 0000000000000001 R09: ffff88010eb50d38 [ 6.078394] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 6.079331] R13: 0000000000000004 R14: 0000000000000001 R15: 0000000000000000 [ 6.080274] FS: 0000000000000000(0000) GS:ffff880115a00000(0000) knlGS:0000000000000000 [ 6.081337] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 6.082092] CR2: ffffea0005000080 CR3: 0000000002824000 CR4: 00000000000006e0 [ 6.083032] Call Trace: [ 6.083371] move_pfn_range_to_zone+0x168/0x180 [ 6.083965] devm_memremap_pages+0x29b/0x480 [ 6.084550] pmem_attach_disk+0x1ae/0x6c0 [nd_pmem] [ 6.085204] ? devm_memremap+0x79/0xb0 [ 6.085714] nd_pmem_probe+0x7e/0xa0 [nd_pmem] [ 6.086320] nvdimm_bus_probe+0x6e/0x160 [libnvdimm] [ 6.086977] driver_probe_device+0x310/0x480 [ 6.087543] __device_attach_driver+0x86/0x100 [ 6.088136] ? __driver_attach+0x110/0x110 [ 6.088681] bus_for_each_drv+0x6e/0xb0 [ 6.089190] __device_attach+0xe2/0x160 [ 6.089705] device_initial_probe+0x13/0x20 [ 6.090266] bus_probe_device+0xa6/0xc0 [ 6.090772] device_add+0x41b/0x660 [ 6.091249] ? lock_acquire+0xa3/0x210 [ 6.091743] nd_async_device_register+0x12/0x40 [libnvdimm] [ 6.092398] async_run_entry_fn+0x3e/0x170 [ 6.092921] process_one_work+0x230/0x680 [ 6.093455] worker_thread+0x3f/0x3b0 [ 6.093930] kthread+0x12f/0x150 [ 6.094362] ? process_one_work+0x680/0x680 [ 6.094903] ? kthread_create_worker_on_cpu+0x70/0x70 [ 6.095574] ret_from_fork+0x3a/0x50 [ 6.096069] Modules linked in: nd_pmem nd_btt dax_pmem device_dax nfit libnvdimm [ 6.097179] CR2: ffffea0005000080 [ 6.097764] ---[ end trace a5b8bd6a5500b68c ]--- - Ross