journalctl complains bios is broken
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kernel: WARNING: CPU: 0 PID: 0 at /build/linux-NMyzc1/linux-4.4.0/drivers/iommu/dmar.c:832 warn_invalid_dmar+0x79/0x90()
kernel: Your BIOS is broken; DMAR reported at address fed92000 returns all ones!
BIOS vendor: coreboot; Ver: CBET4000 4.0; Product Version: 1.0
kernel: Modules linked in:
kernel: CPU: 0 PID: 0 Comm: swapper Not tainted 4.4.0-157-generic #185+8.0trisquel2
kernel: Hardware name: Libiquity Taurinus X200/Taurinus X200, BIOS CBET4000 4.0 10/31/2017
kernel: 0000000000000086 d9474e30ea4e9cae ffffffff81e03d40 ffffffff81415d21
kernel: ffffffff81e03d88 ffffffff81d48988 ffffffff81e03d78 ffffffff810864d2
kernel: 00000000fed92000 ffffffff81d1be02 ffffffff8221000c ffffffff82210044
kernel: Call Trace:
kernel: [ffffffff81415d21] dump_stack+0x63/0x82
kernel: [ffffffff810864d2] warn_slowpath_common+0x82/0xc0
kernel: [ffffffff810865e4] warn_slowpath_fmt_taint+0x54/0x70
kernel: [ffffffff81f9fd26] ? __early_ioremap+0x142/0x1c2
kernel: [ffffffff8156b029] warn_invalid_dmar+0x79/0x90
kernel: [ffffffff81864a76] dmar_validate_one_drhd+0x86/0xc0
kernel: [ffffffff8156b1a9] dmar_walk_remapping_entries+0x89/0x1a0
kernel: [ffffffff81fbce97] detect_intel_iommu+0x61/0xf2
kernel: [ffffffff818649f0] ? xen_swiotlb_init+0x480/0x480
kernel: [ffffffff81f79132] pci_iommu_alloc+0x50/0x6c
kernel: [ffffffff81f89208] mem_init+0x17/0x9d
kernel: [ffffffff81f6aded] start_kernel+0x25a/0x4a4
kernel: [ffffffff81f6a120] ? early_idt_handler_array+0x120/0x120
kernel: [ffffffff81f6a339] x86_64_start_reservations+0x2a/0x2c
kernel: [ffffffff81f6a485] x86_64_start_kernel+0x14a/0x16d
kernel: ---[ end trace 30704173615b582b ]---
