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Date: Tue, 29 May 2018 15:27:14 +0200
From: Igor Mammedov <imammedo@redhat.com>
Message-ID: <20180529152714.232f952c@redhat.com>
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	<20180517081527.14410-2-david@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH v4 01/14] memory-device: drop assert
 related to align and start of address space
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To: David Hildenbrand <david@redhat.com>
Cc: qemu-devel@nongnu.org, qemu-s390x@nongnu.org, "Michael S . Tsirkin" <mst@redhat.com>, Marcel Apfelbaum <marcel@redhat.com>, Paolo Bonzini <pbonzini@redhat.com>, Richard Henderson <rth@twiddle.net>, Eduardo Habkost <ehabkost@redhat.com>, David Gibson <david@gibson.dropbear.id.au>, Markus Armbruster <armbru@redhat.com>, qemu-ppc@nongnu.org, Pankaj Gupta <pagupta@redhat.com>, Alexander Graf <agraf@suse.de>, Cornelia Huck <cohuck@redhat.com>, Christian Borntraeger <borntraeger@de.ibm.com>, Luiz Capitulino <lcapitulino@redhat.com>

On Thu, 17 May 2018 10:15:14 +0200
David Hildenbrand <david@redhat.com> wrote:

> The start of the address space does not have to be aligned for the
> search. Handle this case explicitly when starting the search for a new
> address.
That's true,
but commit message doesn't explain why address_space_start
should be allowed to be non aligned.

At least with this assert we would notice early that
board allocating misaligned address space.
I'd keep the assert unless there is a good reason to drop it.


> 
> Signed-off-by: David Hildenbrand <david@redhat.com>
> ---
>  hw/mem/memory-device.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/hw/mem/memory-device.c b/hw/mem/memory-device.c
> index 3e04f3954e..361d38bfc5 100644
> --- a/hw/mem/memory-device.c
> +++ b/hw/mem/memory-device.c
> @@ -116,7 +116,6 @@ uint64_t memory_device_get_free_addr(MachineState *ms, const uint64_t *hint,
>      address_space_start = ms->device_memory->base;
>      address_space_end = address_space_start +
>                          memory_region_size(&ms->device_memory->mr);
> -    g_assert(QEMU_ALIGN_UP(address_space_start, align) == address_space_start);
>      g_assert(address_space_end >= address_space_start);
>  
>      memory_device_check_addable(ms, size, errp);
> @@ -149,7 +148,7 @@ uint64_t memory_device_get_free_addr(MachineState *ms, const uint64_t *hint,
>              return 0;
>          }
>      } else {
> -        new_addr = address_space_start;
> +        new_addr = QEMU_ALIGN_UP(address_space_start, align);
>      }
>  
>      /* find address range that will fit new memory device */