Re: Discussion of Xenheap problems on AArch64

[Julien Grall <julien@xxxxxxx>]

On 11/05/2021 02:11, Henry Wang wrote:
> Hi Julien,
Hi Henry,

> > From: Julien Grall <julien@xxxxxxx>
> > Hi Henry,
> >
> > On 07/05/2021 05:06, Henry Wang wrote:
> > > > From: Julien Grall <julien@xxxxxxx>
> > > > On 28/04/2021 10:28, Henry Wang wrote:
> > [...]
> >
> > > when I continue booting Xen, I got following error log:
> > >
> > > (XEN) CPU:    0
> > > (XEN) PC:     00000000002b5a5c alloc_boot_pages+0x94/0x98
> > > (XEN) LR:     00000000002ca3bc
> > > (XEN) SP:     00000000002ffde0
> > > (XEN) CPSR:   600003c9 MODE:64-bit EL2h (Hypervisor, handler)
> > > (XEN)
> > > (XEN)   VTCR_EL2: 80000000
> > > (XEN)  VTTBR_EL2: 0000000000000000
> > > (XEN)
> > > (XEN)  SCTLR_EL2: 30cd183d
> > > (XEN)    HCR_EL2: 0000000000000038
> > > (XEN)  TTBR0_EL2: 000000008413c000
> > > (XEN)
> > > (XEN)    ESR_EL2: f2000001
> > > (XEN)  HPFAR_EL2: 0000000000000000
> > > (XEN)    FAR_EL2: 0000000000000000
> > > (XEN)
> > > (XEN) Xen call trace:
> > > (XEN)    [<00000000002b5a5c>] alloc_boot_pages+0x94/0x98 (PC)
> > > (XEN)    [<00000000002ca3bc>] setup_frametable_mappings+0xa4/0x108
> > (LR)
> > > (XEN)    [<00000000002ca3bc>] setup_frametable_mappings+0xa4/0x108
> > > (XEN)    [<00000000002cb988>] start_xen+0x344/0xbcc
> > > (XEN)    [<00000000002001c0>]
> > arm64/head.o#primary_switched+0x10/0x30
> > > (XEN)
> > > (XEN) ****************************************
> > > (XEN) Panic on CPU 0:
> > > (XEN) Xen BUG at page_alloc.c:432
> > > (XEN) ****************************************
> > This is happening without my patch series applied, right? If so, what
> > happen if you apply it?
> No, I am afraid this is with your patch series applied, and that is why I
> am a little bit confused about the error log...
You are hitting the BUG() at the end of alloc_boot_pages(). This is hit 
because the boot allocator couldn't allocate memory for your request.
Would you be able to apply the following diff and paste the output here?

diff --git a/xen/common/page_alloc.c b/xen/common/page_alloc.c
index ace6333c18ea..dbb736fdb275 100644
--- a/xen/common/page_alloc.c
+++ b/xen/common/page_alloc.c
@@ -329,6 +329,8 @@ void __init init_boot_pages(paddr_t ps, paddr_t pe)
     if ( pe <= ps )
         return;

+    printk("%s: ps %"PRI_paddr" pe %"PRI_paddr"\n", __func__, ps, pe);
+
     first_valid_mfn = mfn_min(maddr_to_mfn(ps), first_valid_mfn);

     bootmem_region_add(ps >> PAGE_SHIFT, pe >> PAGE_SHIFT);
@@ -395,6 +397,8 @@ mfn_t __init alloc_boot_pages(unsigned long nr_pfns, 
unsigned long pfn_align)
     unsigned long pg, _e;
     unsigned int i = nr_bootmem_regions;

+    printk("%s: nr_pfns %lu pfn_align %lu\n", __func__, nr_pfns, 
pfn_align);
+
     BUG_ON(!nr_bootmem_regions);

     while ( i-- )

Cheers,

--
Julien Grall