Re: [PATCH v3 1/2] dma-contiguous: Abstract dma_{alloc,free}_contiguous()

From: Nathan Chancellor
Date: Wed May 29 2019 - 14:39:24 EST

Hi Nicolin,

On Thu, May 23, 2019 at 09:06:32PM -0700, Nicolin Chen wrote:
> Both dma_alloc_from_contiguous() and dma_release_from_contiguous()
> are very simply implemented, but requiring callers to pass certain
> parameters like count and align, and taking a boolean parameter to
> check __GFP_NOWARN in the allocation flags. So every function call
> duplicates similar work:
> /* A piece of example */
> unsigned long order = get_order(size);
> size_t count = size >> PAGE_SHIFT;
> page = dma_alloc_from_contiguous(dev, count, order, gfp & __GFP_NOWARN);
> [...]
> dma_release_from_contiguous(dev, page, size >> PAGE_SHIFT);
>
> Additionally, as CMA can be used only in the context which permits
> sleeping, most of callers do a gfpflags_allow_blocking() check and
> a corresponding fallback allocation of normal pages upon any false
> result:
> /* A piece of example */
> if (gfpflags_allow_blocking(flag))
> page = dma_alloc_from_contiguous();
> if (!page)
> page = alloc_pages();
> [...]
> if (!dma_release_from_contiguous(dev, page, count))
> __free_pages(page, get_order(size));
>
> So this patch simplifies those function calls by abstracting these
> operations into the two new functions: dma_{alloc,free}_contiguous.
>
> As some callers of dma_{alloc,release}_from_contiguous() might be
> complicated, this patch just implements these two new functions to
> kernel/dma/direct.c only as an initial step.
>
> Suggested-by: Christoph Hellwig <hch@xxxxxx>
> Signed-off-by: Nicolin Chen <nicoleotsuka@xxxxxxxxx>
> ---

This commit is causing boot failures in QEMU on x86_64 defconfig:

https://travis-ci.com/ClangBuiltLinux/continuous-integration/jobs/203825363

Attached is a bisect log and a boot log with GCC (just to show it is not
a compiler thing).

My QEMU command line is:

qemu-system-x86_64 -m 512m \
-drive file=images/x86_64/rootfs.ext4,format=raw,if=ide \
-append 'console=ttyS0 root=/dev/sda' \
-nographic \
-kernel arch/x86_64/boot/bzImage

and the rootfs is available here:

https://github.com/ClangBuiltLinux/continuous-integration/raw/master/images/x86_64/rootfs.ext4

I haven't seen a report on this yet so apologize if there is already a
fix in the works. Let me know if you need anythnig from me.

Cheers,
Nathan
git bisect start
# good: [9fb67d643f6f1892a08ee3a04ea54022d1060bb0] Merge tag 'pinctrl-v5.2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl
git bisect good 9fb67d643f6f1892a08ee3a04ea54022d1060bb0
# bad: [9a15d2e3fd03e38a6ee7d7bc34d28bb7340f05f2] Add linux-next specific files for 20190529
git bisect bad 9a15d2e3fd03e38a6ee7d7bc34d28bb7340f05f2
# bad: [eb756b9cce06b6c30b478a7ead67ddc0aa52b421] Merge remote-tracking branch 'crypto/master'
git bisect bad eb756b9cce06b6c30b478a7ead67ddc0aa52b421
# bad: [ffd5fc17ee0cd5f90258a8d4e0b87af913943f72] Merge remote-tracking branch 'xtensa/xtensa-for-next'
git bisect bad ffd5fc17ee0cd5f90258a8d4e0b87af913943f72
# bad: [df846fa0031f0e11dbfd5dd7c959cb45b3c0b3e2] Merge remote-tracking branch 'actions/for-next'
git bisect bad df846fa0031f0e11dbfd5dd7c959cb45b3c0b3e2
# good: [673e28ea2b579adcec369cd7f7295142a6b7e017] Merge remote-tracking branch 'usb.current/usb-linus'
git bisect good 673e28ea2b579adcec369cd7f7295142a6b7e017
# good: [d4f1f6efe84b20ff5f3a4874c580c2bee6cba68a] Merge remote-tracking branch 'kvms390-fixes/master'
git bisect good d4f1f6efe84b20ff5f3a4874c580c2bee6cba68a
# bad: [d0756fb0025937a5ed866d27f4452c66b066c089] Merge remote-tracking branch 'dma-mapping/for-next'
git bisect bad d0756fb0025937a5ed866d27f4452c66b066c089
# good: [49af21d0007414838a27eb4ade21277350e8ef1d] Merge remote-tracking branch 'drm-misc-fixes/for-linux-next-fixes'
git bisect good 49af21d0007414838a27eb4ade21277350e8ef1d
# good: [8680aa5a58abfe6087a3d8248c02232d3e05dc80] iommu/dma: Don't remap CMA unnecessarily
git bisect good 8680aa5a58abfe6087a3d8248c02232d3e05dc80
# good: [efd9f10b70689fdeacadc95b6e0ea6dc311fa64f] iommu/dma: Refactor iommu_dma_mmap
git bisect good efd9f10b70689fdeacadc95b6e0ea6dc311fa64f
# good: [b5f75a3639ff3b547e4eee7671e4321a429747a6] arm64: switch copyright boilerplace to SPDX in dma-mapping.c
git bisect good b5f75a3639ff3b547e4eee7671e4321a429747a6
# bad: [fdaeec198ada8c48bff03c85fab542e5b241f5bc] dma-contiguous: add dma_{alloc,free}_contiguous() helpers
git bisect bad fdaeec198ada8c48bff03c85fab542e5b241f5bc
# good: [a84cc69eb53715d37242a21ada398b0d8cd316fc] arm64: trim includes in dma-mapping.c
git bisect good a84cc69eb53715d37242a21ada398b0d8cd316fc
# first bad commit: [fdaeec198ada8c48bff03c85fab542e5b241f5bc] dma-contiguous: add dma_{alloc,free}_contiguous() helpers
c[?7lSeaBIOS (version 1.12.0-20181126_142135-anatol)



iPXE (http://ipxe.org) 00:03.0 C980 PCI2.10 PnP PMM+1FF92110+1FEF2110 C980

Press Ctrl-B to configure iPXE (PCI 00:03.0)...




Booting from ROM..c[?7l.
[ 0.000000] Linux version 5.2.0-rc2-next-20190529 (nathan@archlinux-epyc) (gcc version 8.3.0 (GCC)) #1 SMP Wed May 29 11:26:28 MST 2019

[ 0.000000] Command line: root=/dev/sda console=ttyS0

[ 0.000000] x86/fpu: Supporting XSAVE feature 0x001: 'x87 floating point registers'

[ 0.000000] x86/fpu: Supporting XSAVE feature 0x002: 'SSE registers'

[ 0.000000] x86/fpu: Supporting XSAVE feature 0x004: 'AVX registers'

[ 0.000000] x86/fpu: xstate_offset[2]: 576, xstate_sizes[2]: 256

[ 0.000000] x86/fpu: Enabled xstate features 0x7, context size is 832 bytes, using 'standard' format.

[ 0.000000] BIOS-provided physical RAM map:

[ 0.000000] BIOS-e820: [mem 0x0000000000000000-0x000000000009fbff] usable

[ 0.000000] BIOS-e820: [mem 0x000000000009fc00-0x000000000009ffff] reserved

[ 0.000000] BIOS-e820: [mem 0x00000000000f0000-0x00000000000fffff] reserved

[ 0.000000] BIOS-e820: [mem 0x0000000000100000-0x000000001ffdffff] usable

[ 0.000000] BIOS-e820: [mem 0x000000001ffe0000-0x000000001fffffff] reserved

[ 0.000000] BIOS-e820: [mem 0x00000000feffc000-0x00000000feffffff] reserved

[ 0.000000] BIOS-e820: [mem 0x00000000fffc0000-0x00000000ffffffff] reserved

[ 0.000000] NX (Execute Disable) protection: active

[ 0.000000] SMBIOS 2.8 present.

[ 0.000000] DMI: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-20181126_142135-anatol 04/01/2014

[ 0.000000] tsc: Fast TSC calibration using PIT

[ 0.000000] tsc: Detected 1999.996 MHz processor

[ 0.001281] last_pfn = 0x1ffe0 max_arch_pfn = 0x400000000

[ 0.001327] x86/PAT: Configuration [0-7]: WB WC UC- UC WB WP UC- WT

[ 0.003614] found SMP MP-table at [mem 0x000f5cc0-0x000f5ccf]

[ 0.003654] check: Scanning 1 areas for low memory corruption

[ 0.003674] Using GB pages for direct mapping

[ 0.003756] ACPI: Early table checksum verification disabled

[ 0.003788] ACPI: RSDP 0x00000000000F5AF0 000014 (v00 BOCHS )

[ 0.003793] ACPI: RSDT 0x000000001FFE156F 000030 (v01 BOCHS BXPCRSDT 00000001 BXPC 00000001)

[ 0.003798] ACPI: FACP 0x000000001FFE144B 000074 (v01 BOCHS BXPCFACP 00000001 BXPC 00000001)

[ 0.003802] ACPI: DSDT 0x000000001FFE0040 00140B (v01 BOCHS BXPCDSDT 00000001 BXPC 00000001)

[ 0.003804] ACPI: FACS 0x000000001FFE0000 000040

[ 0.003806] ACPI: APIC 0x000000001FFE14BF 000078 (v01 BOCHS BXPCAPIC 00000001 BXPC 00000001)

[ 0.003808] ACPI: HPET 0x000000001FFE1537 000038 (v01 BOCHS BXPCHPET 00000001 BXPC 00000001)

[ 0.004087] No NUMA configuration found

[ 0.004088] Faking a node at [mem 0x0000000000000000-0x000000001ffdffff]

[ 0.004091] NODE_DATA(0) allocated [mem 0x1ffdc000-0x1ffdffff]

[ 0.004328] Zone ranges:

[ 0.004330] DMA [mem 0x0000000000001000-0x0000000000ffffff]

[ 0.004331] DMA32 [mem 0x0000000001000000-0x000000001ffdffff]

[ 0.004332] Normal empty

[ 0.004332] Movable zone start for each node

[ 0.004333] Early memory node ranges

[ 0.004334] node 0: [mem 0x0000000000001000-0x000000000009efff]

[ 0.004335] node 0: [mem 0x0000000000100000-0x000000001ffdffff]

[ 0.004612] Zeroed struct page in unavailable ranges: 98 pages

[ 0.004613] Initmem setup node 0 [mem 0x0000000000001000-0x000000001ffdffff]

[ 0.006924] ACPI: PM-Timer IO Port: 0x608

[ 0.006930] ACPI: LAPIC_NMI (acpi_id[0xff] dfl dfl lint[0x1])

[ 0.006958] IOAPIC[0]: apic_id 0, version 17, address 0xfec00000, GSI 0-23

[ 0.006960] ACPI: INT_SRC_OVR (bus 0 bus_irq 0 global_irq 2 dfl dfl)

[ 0.006961] ACPI: INT_SRC_OVR (bus 0 bus_irq 5 global_irq 5 high level)

[ 0.006962] ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 9 high level)

[ 0.006963] ACPI: INT_SRC_OVR (bus 0 bus_irq 10 global_irq 10 high level)

[ 0.006964] ACPI: INT_SRC_OVR (bus 0 bus_irq 11 global_irq 11 high level)

[ 0.006967] Using ACPI (MADT) for SMP configuration information

[ 0.006968] ACPI: HPET id: 0x8086a201 base: 0xfed00000

[ 0.006974] smpboot: Allowing 1 CPUs, 0 hotplug CPUs

[ 0.006982] PM: Registered nosave memory: [mem 0x00000000-0x00000fff]

[ 0.006983] PM: Registered nosave memory: [mem 0x0009f000-0x0009ffff]

[ 0.006983] PM: Registered nosave memory: [mem 0x000a0000-0x000effff]

[ 0.006984] PM: Registered nosave memory: [mem 0x000f0000-0x000fffff]

[ 0.006986] [mem 0x20000000-0xfeffbfff] available for PCI devices

[ 0.006989] clocksource: refined-jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 1910969940391419 ns

[ 0.100715] setup_percpu: NR_CPUS:64 nr_cpumask_bits:64 nr_cpu_ids:1 nr_node_ids:1

[ 0.101067] percpu: Embedded 51 pages/cpu s170968 r8192 d29736 u2097152

[ 0.101083] node[0] zonelist: 0:DMA32 0:DMA

[ 0.101086] Built 1 zonelists, mobility grouping on. Total pages: 128873

[ 0.101087] Policy zone: DMA32

[ 0.101089] Kernel command line: root=/dev/sda console=ttyS0

[ 0.102238] Memory: 486332K/523768K available (14340K kernel code, 1311K rwdata, 3128K rodata, 1308K init, 1276K bss, 37436K reserved, 0K cma-reserved)

[ 0.102591] SLUB: HWalign=64, Order=0-3, MinObjects=0, CPUs=1, Nodes=1

[ 0.102930] rcu: Hierarchical RCU implementation.

[ 0.102931] rcu: RCU event tracing is enabled.

[ 0.102932] rcu: RCU restricting CPUs from NR_CPUS=64 to nr_cpu_ids=1.

[ 0.102933] rcu: RCU calculated value of scheduler-enlistment delay is 100 jiffies.

[ 0.102934] rcu: Adjusting geometry for rcu_fanout_leaf=16, nr_cpu_ids=1

[ 0.103054] NR_IRQS: 4352, nr_irqs: 256, preallocated irqs: 16

[ 0.103367] random: get_random_bytes called from start_kernel+0x2c4/0x498 with crng_init=0

[ 0.110098] Console: colour VGA+ 80x25

[ 0.176180] printk: console [ttyS0] enabled

[ 0.176728] ACPI: Core revision 20190509

[ 0.177463] clocksource: hpet: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 19112604467 ns

[ 0.178714] APIC: Switch to symmetric I/O mode setup

[ 0.180399] ..TIMER: vector=0x30 apic1=0 pin1=2 apic2=-1 pin2=-1

[ 0.185697] clocksource: tsc-early: mask: 0xffffffffffffffff max_cycles: 0x39a8554e05d, max_idle_ns: 881590540420 ns

[ 0.187046] Calibrating delay loop (skipped), value calculated using timer frequency.. 3999.99 BogoMIPS (lpj=1999996)

[ 0.188046] pid_max: default: 32768 minimum: 301

[ 0.189060] LSM: Security Framework initializing

[ 0.189653] SELinux: Initializing.

[ 0.190054] *** VALIDATE SELinux ***

[ 0.190556] Dentry cache hash table entries: 65536 (order: 7, 524288 bytes)

[ 0.191100] Inode-cache hash table entries: 32768 (order: 6, 262144 bytes)

[ 0.192058] Mount-cache hash table entries: 1024 (order: 1, 8192 bytes)

[ 0.193047] Mountpoint-cache hash table entries: 1024 (order: 1, 8192 bytes)

[ 0.194137] *** VALIDATE proc ***

[ 0.195066] *** VALIDATE cgroup1 ***

[ 0.195530] *** VALIDATE cgroup2 ***

[ 0.196165] Last level iTLB entries: 4KB 512, 2MB 255, 4MB 127

[ 0.197046] Last level dTLB entries: 4KB 512, 2MB 255, 4MB 127, 1GB 0

[ 0.197853] Spectre V2 : Mitigation: Full AMD retpoline

[ 0.198045] Spectre V2 : Spectre v2 / SpectreRSB mitigation: Filling RSB on context switch

[ 0.199046] Spectre V2 : mitigation: Enabling conditional Indirect Branch Prediction Barrier

[ 0.200046] Speculative Store Bypass: Mitigation: Speculative Store Bypass disabled via prctl and seccomp

[ 0.205525] Freeing SMP alternatives memory: 40K

[ 0.206148] smpboot: CPU0: AMD EPYC 7401P 24-Core Processor (family: 0x17, model: 0x1, stepping: 0x2)

[ 0.207115] Performance Events: Fam17h core perfctr, AMD PMU driver.

[ 0.207932] ... version: 0

[ 0.208047] ... bit width: 48

[ 0.208573] ... generic registers: 6

[ 0.209047] ... value mask: 0000ffffffffffff

[ 0.209714] ... max period: 00007fffffffffff

[ 0.210046] ... fixed-purpose events: 0

[ 0.210556] ... event mask: 000000000000003f

[ 0.211077] rcu: Hierarchical SRCU implementation.

[ 0.211716] Decoding supported only on Scalable MCA processors.

[ 0.212065] smp: Bringing up secondary CPUs ...

[ 0.212640] smp: Brought up 1 node, 1 CPU

[ 0.213047] smpboot: Max logical packages: 1

[ 0.213588] smpboot: Total of 1 processors activated (3999.99 BogoMIPS)

[ 0.214176] devtmpfs: initialized

[ 0.214753] clocksource: jiffies: mask: 0xffffffff max_cycles: 0xffffffff, max_idle_ns: 1911260446275000 ns

[ 0.215050] futex hash table entries: 256 (order: 2, 16384 bytes)

[ 0.215897] PM: RTC time: 18:27:49, date: 2019-05-29

[ 0.216386] NET: Registered protocol family 16

[ 0.217012] audit: initializing netlink subsys (disabled)

[ 0.217253] cpuidle: using governor menu

[ 0.218179] ACPI: bus type PCI registered

[ 0.218756] PCI: Using configuration type 1 for base access

[ 0.219047] PCI: Using configuration type 1 for extended access

[ 0.220053] audit: type=2000 audit(1559154469.038:1): state=initialized audit_enabled=0 res=1

[ 0.222328] HugeTLB registered 2.00 MiB page size, pre-allocated 0 pages

[ 0.223111] cryptomgr_test (20) used greatest stack depth: 15520 bytes left

[ 0.224013] kworker/u2:0 (22) used greatest stack depth: 14664 bytes left

[ 0.224111] kworker/u2:0 (26) used greatest stack depth: 14216 bytes left

[ 0.225711] ACPI: Added _OSI(Module Device)

[ 0.226051] ACPI: Added _OSI(Processor Device)

[ 0.226618] ACPI: Added _OSI(3.0 _SCP Extensions)

[ 0.227047] ACPI: Added _OSI(Processor Aggregator Device)

[ 0.227737] ACPI: Added _OSI(Linux-Dell-Video)

[ 0.228071] ACPI: Added _OSI(Linux-Lenovo-NV-HDMI-Audio)

[ 0.228741] ACPI: Added _OSI(Linux-HPI-Hybrid-Graphics)

[ 0.229545] ACPI: 1 ACPI AML tables successfully acquired and loaded

[ 0.231171] ACPI: Interpreter enabled

[ 0.231666] ACPI: (supports S0 S3 S4 S5)

[ 0.232048] ACPI: Using IOAPIC for interrupt routing

[ 0.232683] PCI: Using host bridge windows from ACPI; if necessary, use "pci=nocrs" and report a bug

[ 0.233119] ACPI: Enabled 2 GPEs in block 00 to 0F

[ 0.235370] ACPI: PCI Root Bridge [PCI0] (domain 0000 [bus 00-ff])

[ 0.236052] acpi PNP0A03:00: _OSC: OS supports [ExtendedConfig ASPM ClockPM Segments MSI HPX-Type3]

[ 0.237078] PCI host bridge to bus 0000:00

[ 0.237602] pci_bus 0000:00: root bus resource [io 0x0000-0x0cf7 window]

[ 0.238048] pci_bus 0000:00: root bus resource [io 0x0d00-0xffff window]

[ 0.238942] pci_bus 0000:00: root bus resource [mem 0x000a0000-0x000bffff window]

[ 0.239048] pci_bus 0000:00: root bus resource [mem 0x20000000-0xfebfffff window]

[ 0.240014] pci_bus 0000:00: root bus resource [mem 0x100000000-0x17fffffff window]

[ 0.240047] pci_bus 0000:00: root bus resource [bus 00-ff]

[ 0.240789] pci 0000:00:00.0: [8086:1237] type 00 class 0x060000

[ 0.241446] pci 0000:00:01.0: [8086:7000] type 00 class 0x060100

[ 0.242459] pci 0000:00:01.1: [8086:7010] type 00 class 0x010180

[ 0.244902] pci 0000:00:01.1: reg 0x20: [io 0xc040-0xc04f]

[ 0.245838] pci 0000:00:01.1: legacy IDE quirk: reg 0x10: [io 0x01f0-0x01f7]

[ 0.246049] pci 0000:00:01.1: legacy IDE quirk: reg 0x14: [io 0x03f6]

[ 0.246897] pci 0000:00:01.1: legacy IDE quirk: reg 0x18: [io 0x0170-0x0177]

[ 0.247047] pci 0000:00:01.1: legacy IDE quirk: reg 0x1c: [io 0x0376]

[ 0.248021] pci 0000:00:01.3: [8086:7113] type 00 class 0x068000

[ 0.248360] pci 0000:00:01.3: quirk: [io 0x0600-0x063f] claimed by PIIX4 ACPI

[ 0.249053] pci 0000:00:01.3: quirk: [io 0x0700-0x070f] claimed by PIIX4 SMB

[ 0.250137] pci 0000:00:02.0: [1234:1111] type 00 class 0x030000

[ 0.252059] pci 0000:00:02.0: reg 0x10: [mem 0xfd000000-0xfdffffff pref]

[ 0.256072] pci 0000:00:02.0: reg 0x18: [mem 0xfebf0000-0xfebf0fff]

[ 0.263058] pci 0000:00:02.0: reg 0x30: [mem 0xfebe0000-0xfebeffff pref]

[ 0.264378] pci 0000:00:03.0: [8086:100e] type 00 class 0x020000

[ 0.266050] pci 0000:00:03.0: reg 0x10: [mem 0xfebc0000-0xfebdffff]

[ 0.268049] pci 0000:00:03.0: reg 0x14: [io 0xc000-0xc03f]

[ 0.274058] pci 0000:00:03.0: reg 0x30: [mem 0xfeb80000-0xfebbffff pref]

[ 0.276310] ACPI: PCI Interrupt Link [LNKA] (IRQs 5 *10 11)

[ 0.277301] ACPI: PCI Interrupt Link [LNKB] (IRQs 5 *10 11)

[ 0.278248] ACPI: PCI Interrupt Link [LNKC] (IRQs 5 10 *11)

[ 0.279247] ACPI: PCI Interrupt Link [LNKD] (IRQs 5 10 *11)

[ 0.280166] ACPI: PCI Interrupt Link [LNKS] (IRQs *9)

[ 0.281410] pci 0000:00:02.0: vgaarb: setting as boot VGA device

[ 0.282044] pci 0000:00:02.0: vgaarb: VGA device added: decodes=io+mem,owns=io+mem,locks=none

[ 0.282056] pci 0000:00:02.0: vgaarb: bridge control possible

[ 0.283054] vgaarb: loaded

[ 0.284164] SCSI subsystem initialized

[ 0.285174] ACPI: bus type USB registered

[ 0.286088] usbcore: registered new interface driver usbfs

[ 0.287074] usbcore: registered new interface driver hub

[ 0.288087] usbcore: registered new device driver usb

[ 0.289088] pps_core: LinuxPPS API ver. 1 registered

[ 0.290054] pps_core: Software ver. 5.3.6 - Copyright 2005-2007 Rodolfo Giometti <giometti@xxxxxxxx>

[ 0.291064] PTP clock support registered

[ 0.292127] EDAC MC: Ver: 3.0.0

[ 0.293326] Advanced Linux Sound Architecture Driver Initialized.

[ 0.294072] PCI: Using ACPI for IRQ routing

[ 0.295369] NetLabel: Initializing

[ 0.296052] NetLabel: domain hash size = 128

[ 0.297050] NetLabel: protocols = UNLABELED CIPSOv4 CALIPSO

[ 0.298079] NetLabel: unlabeled traffic allowed by default

[ 0.299200] hpet0: at MMIO 0xfed00000, IRQs 2, 8, 0

[ 0.300053] hpet0: 3 comparators, 64-bit 100.000000 MHz counter

[ 0.306070] clocksource: Switched to clocksource tsc-early

[ 0.379516] VFS: Disk quotas dquot_6.6.0

[ 0.380072] VFS: Dquot-cache hash table entries: 512 (order 0, 4096 bytes)

[ 0.380975] *** VALIDATE hugetlbfs ***

[ 0.381470] pnp: PnP ACPI init

[ 0.382179] pnp: PnP ACPI: found 6 devices

[ 0.388273] clocksource: acpi_pm: mask: 0xffffff max_cycles: 0xffffff, max_idle_ns: 2085701024 ns

[ 0.389427] pci_bus 0000:00: resource 4 [io 0x0000-0x0cf7 window]

[ 0.390251] pci_bus 0000:00: resource 5 [io 0x0d00-0xffff window]

[ 0.391054] pci_bus 0000:00: resource 6 [mem 0x000a0000-0x000bffff window]

[ 0.391914] pci_bus 0000:00: resource 7 [mem 0x20000000-0xfebfffff window]

[ 0.392777] pci_bus 0000:00: resource 8 [mem 0x100000000-0x17fffffff window]

[ 0.393680] NET: Registered protocol family 2

[ 0.394330] tcp_listen_portaddr_hash hash table entries: 256 (order: 0, 4096 bytes)

[ 0.395302] TCP established hash table entries: 4096 (order: 3, 32768 bytes)

[ 0.396246] TCP bind hash table entries: 4096 (order: 4, 65536 bytes)

[ 0.397089] TCP: Hash tables configured (established 4096 bind 4096)

[ 0.397884] UDP hash table entries: 256 (order: 1, 8192 bytes)

[ 0.398624] UDP-Lite hash table entries: 256 (order: 1, 8192 bytes)

[ 0.399421] NET: Registered protocol family 1

[ 0.400031] RPC: Registered named UNIX socket transport module.

[ 0.400773] RPC: Registered udp transport module.

[ 0.401367] RPC: Registered tcp transport module.

[ 0.401958] RPC: Registered tcp NFSv4.1 backchannel transport module.

[ 0.402824] pci 0000:00:01.0: PIIX3: Enabling Passive Release

[ 0.403549] pci 0000:00:00.0: Limiting direct PCI/PCI transfers

[ 0.404288] pci 0000:00:01.0: Activating ISA DMA hang workarounds

[ 0.405080] pci 0000:00:02.0: Video device with shadowed ROM at [mem 0x000c0000-0x000dffff]

[ 0.406129] PCI: CLS 0 bytes, default 64

[ 0.406744] check: Scanning for low memory corruption every 60 seconds

[ 0.407727] Initialise system trusted keyrings

[ 0.408320] workingset: timestamp_bits=56 max_order=17 bucket_order=0

[ 0.410320] NFS: Registering the id_resolver key type

[ 0.410953] Key type id_resolver registered

[ 0.411481] Key type id_legacy registered

[ 0.412107] Key type asymmetric registered

[ 0.412623] Asymmetric key parser 'x509' registered

[ 0.413235] Block layer SCSI generic (bsg) driver version 0.4 loaded (major 251)

[ 0.414152] io scheduler mq-deadline registered

[ 0.414715] io scheduler kyber registered

[ 0.415305] input: Power Button as /devices/LNXSYSTM:00/LNXPWRBN:00/input/input0

[ 0.416234] ACPI: Power Button [PWRF]

[ 0.416819] Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled

[ 0.440750] 00:05: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A

[ 0.441978] Non-volatile memory driver v1.3

[ 0.442575] Linux agpgart interface v0.103

[ 0.444240] loop: module loaded

[ 0.444948] ata_piix 0000:00:01.1: failed to start port 0 (errno=-12)

[ 0.445938] ata_piix: probe of 0000:00:01.1 failed with error -12

[ 0.446748] e100: Intel(R) PRO/100 Network Driver, 3.5.24-k2-NAPI

[ 0.447504] e100: Copyright(c) 1999-2006 Intel Corporation

[ 0.448196] e1000: Intel(R) PRO/1000 Network Driver - version 7.3.21-k8-NAPI

[ 0.449116] e1000: Copyright (c) 1999-2006 Intel Corporation.

[ 0.462026] PCI Interrupt Link [LNKC] enabled at IRQ 11

[ 0.764450] e1000 0000:00:03.0 eth0: (PCI:33MHz:32-bit) 52:54:00:12:34:56

[ 0.765305] e1000 0000:00:03.0 eth0: Intel(R) PRO/1000 Network Connection

[ 0.766192] e1000e: Intel(R) PRO/1000 Network Driver - 3.2.6-k

[ 0.766955] e1000e: Copyright(c) 1999 - 2015 Intel Corporation.

[ 0.767732] sky2: driver version 1.30

[ 0.768275] ehci_hcd: USB 2.0 'Enhanced' Host Controller (EHCI) Driver

[ 0.769128] ehci-pci: EHCI PCI platform driver

[ 0.769710] ohci_hcd: USB 1.1 'Open' Host Controller (OHCI) Driver

[ 0.770503] ohci-pci: OHCI PCI platform driver

[ 0.771081] uhci_hcd: USB Universal Host Controller Interface driver

[ 0.771910] usbcore: registered new interface driver usblp

[ 0.772628] usbcore: registered new interface driver usb-storage

[ 0.773424] i8042: PNP: PS/2 Controller [PNP0303:KBD,PNP0f13:MOU] at 0x60,0x64 irq 1,12

[ 0.775080] serio: i8042 KBD port at 0x60,0x64 irq 1

[ 0.775729] serio: i8042 AUX port at 0x60,0x64 irq 12

[ 0.776961] input: AT Translated Set 2 keyboard as /devices/platform/i8042/serio0/input/input1

[ 0.779751] rtc_cmos 00:00: RTC can wake from S4

[ 0.780682] rtc_cmos 00:00: registered as rtc0

[ 0.781298] rtc_cmos 00:00: alarms up to one day, y3k, 114 bytes nvram, hpet irqs

[ 0.782350] device-mapper: ioctl: 4.40.0-ioctl (2019-01-18) initialised: dm-devel@xxxxxxxxxx

[ 0.783478] hidraw: raw HID events driver (C) Jiri Kosina

[ 0.784247] usbcore: registered new interface driver usbhid

[ 0.784940] usbhid: USB HID core driver

[ 0.785877] Initializing XFRM netlink socket

[ 0.786497] NET: Registered protocol family 10

[ 0.787219] Segment Routing with IPv6

[ 0.787713] sit: IPv6, IPv4 and MPLS over IPv4 tunneling driver

[ 0.788537] NET: Registered protocol family 17

[ 0.789122] Key type dns_resolver registered

[ 0.789708] mce: Using 10 MCE banks

[ 0.790165] sched_clock: Marking stable (714371390, 75773427)->(925568491, -135423674)

[ 0.791221] registered taskstats version 1

[ 0.791733] Loading compiled-in X.509 certificates

[ 0.792509] PM: Magic number: 3:11:495

[ 0.793015] printk: console [netcon0] enabled

[ 0.793565] netconsole: network logging started

[ 0.794166] cfg80211: Loading compiled-in X.509 certificates for regulatory database

[ 0.795403] cfg80211: Loaded X.509 cert 'sforshee: 00b28ddf47aef9cea7'

[ 0.796230] ALSA device list:

[ 0.796679] No soundcards found.

[ 0.797386] platform regulatory.0: Direct firmware load for regulatory.db failed with error -2

[ 0.798530] cfg80211: failed to load regulatory.db

[ 1.380351] input: ImExPS/2 Generic Explorer Mouse as /devices/platform/i8042/serio1/input/input3

[ 1.383202] md: Waiting for all devices to be available before autodetect

[ 1.385280] md: If you don't use raid, use raid=noautodetect

[ 1.387215] md: Autodetecting RAID arrays.

[ 1.388498] md: autorun ...

[ 1.389381] md: ... autorun DONE.

[ 1.390461] VFS: Cannot open root device "sda" or unknown-block(0,0): error -6

[ 1.392649] Please append a correct "root=" boot option; here are the available partitions:

[ 1.395141] Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)

[ 1.397600] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.2.0-rc2-next-20190529 #1

[ 1.399793] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-20181126_142135-anatol 04/01/2014

[ 1.402816] Call Trace:

[ 1.403577] dump_stack+0x46/0x60

[ 1.404586] panic+0xf6/0x2b7

[ 1.405512] mount_block_root+0x191/0x23b

[ 1.406724] ? do_early_param+0x89/0x89

[ 1.407881] mount_root+0x10a/0x128

[ 1.408952] prepare_namespace+0x130/0x166

[ 1.410195] kernel_init_freeable+0x1df/0x1ea

[ 1.411501] ? rest_init+0x9a/0x9a

[ 1.412533] kernel_init+0x5/0xf6

[ 1.413536] ret_from_fork+0x22/0x40

[ 1.417612] Kernel Offset: 0x800000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)

[ 1.420749] ---[ end Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0) ]---