Re: [PATCH 14/15] x86/PVH: log Dom0's E820 map earlier

[Jan Beulich <jbeulich@xxxxxxxx>]

On 16.10.2026 09:24, Roger Pau Monné wrote:
> On Mon, Oct 12, 2026 at 10:26:24AM +0200, Jan Beulich wrote:
>> Do this as soon as it's final. For debug builds also mark it final, with
>> assertions put in place to make sure it won't further be altered. (For a
>> release build such further altering isn't the end of the world normally,
>> so the situation is left alone there.)
>>
>> Switch to using %pd while moving the code up.
>>
>> Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
>>
>> --- a/xen/arch/x86/hvm/dom0_build.c
>> +++ b/xen/arch/x86/hvm/dom0_build.c
>> @@ -46,6 +46,9 @@
>>   */
>>  #define HVM_VM86_TSS_SIZE 265
>>  
>> +/* Marker set once Dom0's E820 isn't supposed to change anymore */
>> +static bool __initdata e820_finalized;
>> +
>>  static unsigned int __initdata acpi_intr_overrides;
>>  static struct acpi_madt_interrupt_override __initdata *intsrcovr;
>>  
>> @@ -195,6 +198,8 @@ static int __init pvh_steal_ram(struct d
>>      struct e820entry *good = NULL;
>>      unsigned int i = d->arch.nr_e820;
>>  
>> +    ASSERT(!e820_finalized);
>> +
>>      /*
>>       * Alignment 0 should be set to 1, so it doesn't wrap around in the
>>       * calculations below.
>> @@ -241,6 +246,8 @@ static int __init pvh_add_mem_range(stru
>>      struct e820entry *map;
>>      unsigned int i;
>>  
>> +    ASSERT(!e820_finalized);
>> +
>>      for ( i = 0; i < d->arch.nr_e820; i++ )
>>      {
>>          uint64_t rs = d->arch.e820[i].addr;
>> @@ -1759,6 +1766,13 @@ int __init dom0_construct_pvh(const stru
>>  
>>      pvh_place_initrd(bd, &elf, &initrd, &blob_start, &blob_end);
>>  
>> +    if ( opt_dom0_verbose )
>> +    {
>> +        printk("%pd memory map:\n", d);
>> +        print_e820_memory_map(d->arch.e820, d->arch.nr_e820);
>> +        e820_finalized = true;
> 
> You want to pull setting e820_finalized out of the if body, so it's
> not tied to opt_dom0_verbose being set I think?

Hmm, yes - not quite sure what I was thinking.

> The rest LGTM, so:
> 
> Acked-by: Roger Pau Monné <roger@xxxxxxxxxxxxxx>
> 
> With the above change.

Thanks.

Jan