Re: [PATCH v2 8/8] xen: arm: allocate more than one bank for 1:1 domain 0 if needed

[Julien Grall <julien.grall@linaro.org>]

On 18/06/14 09:27, Ian Campbell wrote:
> On Tue, 2014-06-17 at 18:58 +0100, Julien Grall wrote:
>> Hi Ian,
>>
>> On 06/11/2014 05:40 PM, Ian Campbell wrote:
>>> +    /*
>>> +     * First try and allocate the largest thing we can as low as
>>> +     * possible to be bank 0.
>>> +     */
>>> +    while ( order > min_low_order )
>>> +    {
>>> +        for ( bits = order ; bits < (lowmem ? 32 : PADDR_BITS); bits++ )
>>> +        {
>>> +            pg = alloc_domheap_pages(d, order, MEMF_bits(bits));
>>> +            if ( pg != NULL )
>>> +                goto got_bank0;
>>> +        }
>>> +        order--;
>>> +    }
>>> +
>>> +    panic("Unable to allocate first memory bank");
>>
>> I gave a try to this patch in stand-alone on the versatile express and I
>> hit this panic.
>>
>> Xen is trying to allocate 128Mb for the first bank. It was working
>> without this patch.
> 
> What is your dom0_mem and how much ram does the system have?

I use the default value from Xen i.e 128MB. The platform has 1GB of RAM
(see below Xen log with early printk enabled).

- UART enabled -
- CPU 00000000 booting -
- Xen starting in Hyp mode -
- Zero BSS -
- Setting up control registers -
- Turning on paging -
- Ready -
(XEN) Checking for initrd in /chosen
(XEN) RAM: 0000000080000000 - 000000009fffffff
(XEN) RAM: 00000000a0000000 - 00000000bfffffff
(XEN)
(XEN) MODULE[1]: 000000009fee6000 - 000000009feea000
(XEN) MODULE[2]: 00000000a0008000 - 00000000a033f458
(XEN)  RESVD[0]: 0000000081f00000 - 0000000081f04000
(XEN)  RESVD[1]: 000000009fee6000 - 000000009feea000
(XEN)
(XEN) Command line: noreboot sync_console console=dtuart dtuart=serial0
(XEN) Placing Xen at 0x00000000bfe00000-0x00000000c0000000
(XEN) Xen heap: 00000000b6000000-00000000be000000 (32768 pages)
(XEN) Dom heap: 229376 pages
(XEN) Domain heap initialised
(XEN) Looking for UART console serial0
Xen 4.5-unstable
(XEN) Xen version 4.5-unstable (julien@cam.xci-test.com) (arm-linux-gnueabihf-gcc (crosstool-NG linaro-1.13.1-4.8-2014.01 - Linaro GCC 2013.11) 4.8.3 20140106 (prerelease)) debug=y Wed Jun 18 09:52:52 BST 2014
(XEN) Latest ChangeSet: Wed Jun 11 17:40:04 2014 +0100 git:bdee6c6
(XEN) Console output is synchronous.
(XEN) Processor: 412fc0f1: "ARM Limited", variant: 0x2, part 0xc0f, rev 0x1
(XEN) 32-bit Execution:
(XEN)   Processor Features: 00001131:00011011
(XEN)     Instruction Sets: AArch32 Thumb Thumb-2 ThumbEE Jazelle
(XEN)     Extensions: GenericTimer Security
(XEN)   Debug Features: 02010555
(XEN)   Auxiliary Features: 00000000
(XEN)   Memory Model Features: 10201105 20000000 01240000 02102211
(XEN)  ISA Features: 02101110 13112111 21232041 11112131 10011142 00000000
(XEN) Platform: VERSATILE EXPRESS
(XEN) Set SYS_FLAGS to 00000000bfe0004c (0020004c)
(XEN) Generic Timer IRQ: phys=30 hyp=26 virt=27
(XEN) Using generic timer at 24000 KHz
(XEN) GIC initialization:
(XEN)         gic_dist_addr=000000002c001000
(XEN)         gic_cpu_addr=000000002c002000
(XEN)         gic_hyp_addr=000000002c004000
(XEN)         gic_vcpu_addr=000000002c006000
(XEN)         gic_maintenance_irq=25
(XEN) GIC: 192 lines, 5 cpus, secure (IID 0200043b).
(XEN) Using scheduler: SMP Credit Scheduler (credit)
(XEN) I/O virtualisation disabled
(XEN) Allocated console ring of 16 KiB.
(XEN) VFP implementer 0x41 architecture 4 part 0x30 variant 0xf rev 0x0
(XEN) Bringing up CPU1
- CPU 00000001 booting -
- Xen starting in Hyp mode -
- Setting up control registers -
- Turning on paging -
- Ready -
(XEN) CPU 1 booted.
(XEN) Brought up 2 CPUs
(XEN) *** LOADING DOMAIN 0 ***
(XEN) Loading kernel from boot module 2
(XEN) Allocating 1:1 mappings totalling 128MB for dom0:
(XEN)
(XEN) ****************************************
(XEN) Panic on CPU 0:
(XEN) Unable to allocate first memory bank
(XEN) ****************************************
(XEN)
(XEN) Manual reset required ('noreboot' specified)

Regards,

-- 
Julien Grall