Additional info:
reporter:       libreport-2.9.5
WARNING: CPU: 0 PID: 0 at drivers/iommu/dmar.c:848 warn_invalid_dmar.part.10+0x57/0x60
Modules linked in:
CPU: 0 PID: 0 Comm: swapper Not tainted 4.19.0-0.rc4.git1.1.fc30.x86_64 #1
Hardware name: Notebook                         W230SS                 /W230SS                 , BIOS 4.6.5 04/08/2015
RIP: 0010:warn_invalid_dmar.part.10+0x57/0x60
Code: 1a 00 bf 01 00 00 00 49 89 c4 e8 14 47 1a 00 4d 89 e9 4d 89 e0 48 89 ea 48 89 c1 48 89 de 48 c7 c7 38 a8 37 b9 e8 bd d2 a1 ff <0f> 0b 5b 5d 41 5c 41 5d c3 e8 7b 26 56 00 85 d2 7f 03 31 c0 c3 8d
RSP: 0000:ffffffffb9603e00 EFLAGS: 00010086
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffffffffb961a7c0 RSI: 0000000000000000 RDI: ffffffffb8139680
RBP: ffffffffb933508a R08: 0000000000000001 R09: 0000000000000001
R10: 0000000000000001 R11: 0000000000000000 R12: ffffffffbb26901c
R13: ffffffffbb26906c R14: ffffffffb9603e80 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff961f9ea00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff961fafdff000 CR3: 0000000134612001 CR4: 00000000000606b0
Call Trace:
 dmar_validate_one_drhd+0xc0/0xd0
 dmar_walk_remapping_entries+0xa2/0x140
 detect_intel_iommu+0x64/0xe6
 ? xen_swiotlb_init+0x4e0/0x4e0
 pci_iommu_alloc+0x51/0x6c
 mem_init+0x16/0xb9
 start_kernel+0x2b8/0x572
 secondary_startup_64+0xa4/0xb0
irq event stamp: 0
hardirqs last  enabled at (0): [<0000000000000000>]           (null)
hardirqs last disabled at (0): [<0000000000000000>]           (null)
softirqs last  enabled at (0): [<0000000000000000>]           (null)
softirqs last disabled at (0): [<0000000000000000>]           (null)

Potential duplicate: bug 1590887