Re: [Qemu-devel] PMON2000 compilation and kernel question

[John Snow]

On 3/6/19 11:01 AM, Andrew Randrianasulu wrote:
>> This could be some missing or buggy emulation. Maybe if you can get some 
>> debug logs from kernel that could tell what it's doing. Usually at least -d 
>> unimp,guest_errors options are recommended for debugging but if nothing is 
>> printed then it's harder to find out what's causing the hang.
> 
> This was kernel dying in ata subsystem:
> 

I'm very late to the party here; but you could try enabling tracing for
the ATA code and that might give a better picture as to what's going wrong;

warning that if you enable every last trace it does get QUITE chatty (it
includes data IO dumps) but it might give us a better picture.

See hw/ide/trace-events and try enabling everything except the events
labeled "verbose" as a first step.

> [    1.340000] io scheduler noop registered
> [    1.340000] io scheduler deadline registered
> [    1.340000] io scheduler cfq registered (default)
> [    1.352000] Serial: 8250/16550 driver, 4 ports, IRQ sharing disabled
> [    1.388000] console [ttyS0] disabled
> [    1.424000] serial8250.0: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) 
> is a 16550A
> [    1.432000] console [ttyS0] enabled
> [    1.432000] console [ttyS0] enabled
> [    1.432000] bootconsole [early0] disabled
> [    1.432000] bootconsole [early0] disabled
> [    1.472000] scsi0 : pata_via
> [    1.476000] scsi1 : pata_via
> [    1.480000] ata1: PATA max UDMA/100 cmd 0x4450 ctl 0x4460 bmdma 0x4440
> [    1.484000] ata2: PATA max UDMA/100 cmd 0x4458 ctl 0x4464 bmdma 0x4448
> [    1.524000] serio: i8042 KBD port at 0x60,0x64 irq 1
> [    1.524000] serio: i8042 AUX port at 0x60,0x64 irq 12
> [    1.532000] mousedev: PS/2 mouse device common for all mice
> [    1.552000] rtc_cmos rtc_cmos: rtc core: registered rtc_cmos as rtc0
> [    1.552000] rtc_cmos rtc_cmos: alarms up to one day, 114 bytes nvram
> [    1.556000] ledtrig-cpu: registered to indicate activity on CPUs
> [    1.556000] TCP: cubic registered
> [    1.560000] NET: Registered protocol family 10
> [    1.588000] mip6: Mobile IPv6
> [    1.588000] NET: Registered protocol family 17
> [    1.588000] mpls_gso: MPLS GSO support
> [    1.596000] registered taskstats version 1
> [    1.612000] rtc_cmos rtc_cmos: setting system clock to 2019-03-06 15:48:12 
> UTC (1551887292)
> [    1.684000] input: AT Raw Set 2 keyboard as 
> /devices/platform/i8042/serio0/input/input0
> [    1.724000] ata1.00: ATA-7: QEMU HARDDISK, 2.5+, max UDMA/100
> [    1.724000] ata1.00: 204800 sectors, multi 16: LBA48
> [    1.728000] ata1.00: limited to UDMA/33 due to 40-wire cable
> [    1.736000] ata1.00: configured for UDMA/33
> [    1.796000] scsi 0:0:0:0: Direct-Access     ATA      QEMU HARDDISK    2.5+ 
> PQ: 0 ANSI: 5
> [    1.820000] sd 0:0:0:0: [sda] 204800 512-byte logical blocks: (104 MB/100 
> MiB)
> [    1.832000] sd 0:0:0:0: [sda] Write Protect is off
> [    1.836000] sd 0:0:0:0: [sda] Write cache: enabled, read cache: enabled, 
> doesn't support DPO or FUA
> [    1.864000] Data bus error, epc == ffffffff804157d8, ra == ffffffff804f7ddc
> [    1.864000] Oops[#1]:
> 
> for 
> 
> mips64el-softmmu/qemu-system-mips64el -M fulong2e  -kernel 
> /dev/shm/boot/vmlinux-3.16.0-4-loongson-2e -hda /dev/shm/LONGSOON_disk  
> -cdrom /dev/shm/debian-8.0.0-mipsel-xfce-CD-1.iso -nographic -d 
> unimp,guest_errors -append "console=ttyS0" > VMLINUX_3.16.log 2>&1
> 
> and without ata disk but with just CD it moved into 'normal' panic (no root 
> device)
> 
> [    1.480000] console [ttyS0] enabled
> [    1.480000] console [ttyS0] enabled
> [    1.484000] bootconsole [early0] disabled
> [    1.484000] bootconsole [early0] disabled
> [    1.524000] scsi0 : pata_via
> [    1.528000] scsi1 : pata_via
> [    1.532000] ata1: PATA max UDMA/100 cmd 0x4450 ctl 0x4460 bmdma 0x4440
> [    1.536000] ata2: PATA max UDMA/100 cmd 0x4458 ctl 0x4464 bmdma 0x4448
> [    1.580000] serio: i8042 KBD port at 0x60,0x64 irq 1
> [    1.584000] serio: i8042 AUX port at 0x60,0x64 irq 12
> [    1.596000] mousedev: PS/2 mouse device common for all mice
> [    1.616000] rtc_cmos rtc_cmos: rtc core: registered rtc_cmos as rtc0
> [    1.616000] rtc_cmos rtc_cmos: alarms up to one day, 114 bytes nvram
> [    1.620000] ledtrig-cpu: registered to indicate activity on CPUs
> [    1.624000] TCP: cubic registered
> [    1.624000] NET: Registered protocol family 10
> [    1.648000] mip6: Mobile IPv6
> [    1.652000] NET: Registered protocol family 17
> [    1.652000] mpls_gso: MPLS GSO support
> [    1.656000] registered taskstats version 1
> [    1.688000] rtc_cmos rtc_cmos: setting system clock to 2019-03-06 15:50:38 
> UTC (1551887438)
> [    1.752000] input: AT Raw Set 2 keyboard as 
> /devices/platform/i8042/serio0/input/input0
> [    1.912000] ata2.00: ATAPI: QEMU DVD-ROM, 2.5+, max UDMA/100
> [    1.916000] ata2.00: limited to UDMA/33 due to 40-wire cable
> [    1.924000] ata2.00: configured for UDMA/33
> [    2.604000] input: ImExPS/2 Generic Explorer Mouse as 
> /devices/platform/i8042/serio1/input/input2
> [    6.928000] ata2.00: qc timeout (cmd 0xa0)
> [    6.928000] ata2.00: TEST_UNIT_READY failed (err_mask=0x4)
> [    7.088000] ata2.00: configured for UDMA/33
> [   12.092000] ata2.00: qc timeout (cmd 0xa0)
> [   12.096000] ata2.00: TEST_UNIT_READY failed (err_mask=0x4)
> [   12.096000] ata2.00: limiting speed to UDMA/33:PIO3
> [   12.252000] ata2.00: configured for UDMA/33
> [   17.252000] ata2.00: qc timeout (cmd 0xa0)
> [   17.252000] ata2.00: TEST_UNIT_READY failed (err_mask=0x4)
> [   17.256000] ata2.00: disabled
> [   17.260000] ata2: soft resetting link
> [   17.420000] ata2: EH complete
> [   17.428000] VFS: Cannot open root device "(null)" or unknown-block(0,0): 
> error -6
> [   17.428000] Please append a correct "root=" boot option; here are the 
> available partitions:
> [   17.432000] Kernel panic - not syncing: VFS: Unable to mount root fs on 
> unknown-block(0,0)
> [   17.432000] ---[ end Kernel panic - not syncing: VFS: Unable to mount root 
> fs on unknown-block(0,0)
> 
> vmlinux-2e also boots (if I redirect output to serial console), but not very 
> verbose :/
> 
> Scaning....
> =========================================================
> =========================================================
> not find usb drivers...
> 
> mips64el-softmmu/qemu-system-mips64el -M fulong2e  -kernel 
> /dev/shm/vmlinux-2e  -cdrom /dev/shm/debian-8.0.0-mipsel-xfce-CD-1.iso 
> -nographic -d unimp,guest_errors -append "console=ttyS0"
> 
> Hm. Note I skipped adding ati-vga device in those tests, because Debian 3.16 
> kernel was panicing in radeon code too.
> 

-- 
—js