diff mbox series

[5/8] ppc/pnv: Add an assert when calculating the RAM distribution on chips

Message ID 20210901094153.227671-6-clg@kaod.org (mailing list archive)
State New, archived
Headers show
Series ppc: cleanups | expand

Commit Message

Cédric Le Goater Sept. 1, 2021, 9:41 a.m. UTC 
Signed-off-by: Cédric Le Goater <clg@kaod.org>
---
 hw/ppc/pnv.c | 2 ++
 1 file changed, 2 insertions(+)

Comments

David Gibson Sept. 2, 2021, 1:37 a.m. UTC | #1 
On Wed, Sep 01, 2021 at 11:41:50AM +0200, Cédric Le Goater wrote:
> Signed-off-by: Cédric Le Goater <clg@kaod.org>

Uh.. I thought the proposed assert was about making it clear there
wouldn't be a divide by zero, which would want > 1, not < 2.

> ---
>  hw/ppc/pnv.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/hw/ppc/pnv.c b/hw/ppc/pnv.c
> index a62e90b15e27..761b82be7401 100644
> --- a/hw/ppc/pnv.c
> +++ b/hw/ppc/pnv.c
> @@ -723,6 +723,8 @@ static uint64_t pnv_chip_get_ram_size(PnvMachineState *pnv, int chip_id)
>          return QEMU_ALIGN_DOWN(ram_per_chip, 1 * MiB);
>      }
>  
> +    assert(pnv->num_chips < 2);
> +
>      ram_per_chip = (machine->ram_size - 1 * GiB) / (pnv->num_chips - 1);
>      return chip_id == 0 ? 1 * GiB : QEMU_ALIGN_DOWN(ram_per_chip, 1 * MiB);
>  }
Cédric Le Goater Sept. 2, 2021, 6:28 a.m. UTC | #2 
On 9/2/21 3:37 AM, David Gibson wrote:
> On Wed, Sep 01, 2021 at 11:41:50AM +0200, Cédric Le Goater wrote:
>> Signed-off-by: Cédric Le Goater <clg@kaod.org>
> 
> Uh.. I thought the proposed assert was about making it clear there
> wouldn't be a divide by zero, which would want > 1, not < 2.

This is very wrong :) How did I come with this ? 

I will keep it for the next round of powernv10. Are you ready for a v2 ? 


Thanks, 

C.
David Gibson Sept. 2, 2021, 6:33 a.m. UTC | #3 
On Thu, Sep 02, 2021 at 08:28:49AM +0200, Cédric Le Goater wrote:
> On 9/2/21 3:37 AM, David Gibson wrote:
> > On Wed, Sep 01, 2021 at 11:41:50AM +0200, Cédric Le Goater wrote:
> >> Signed-off-by: Cédric Le Goater <clg@kaod.org>
> > 
> > Uh.. I thought the proposed assert was about making it clear there
> > wouldn't be a divide by zero, which would want > 1, not < 2.
> 
> This is very wrong :) How did I come with this ? 
> 
> I will keep it for the next round of powernv10. Are you ready for a
> v2 ?

Ready enough.
diff mbox series

Patch

diff --git a/hw/ppc/pnv.c b/hw/ppc/pnv.c
index a62e90b15e27..761b82be7401 100644
--- a/hw/ppc/pnv.c
+++ b/hw/ppc/pnv.c
@@ -723,6 +723,8 @@  static uint64_t pnv_chip_get_ram_size(PnvMachineState *pnv, int chip_id)
         return QEMU_ALIGN_DOWN(ram_per_chip, 1 * MiB);
     }
 
+    assert(pnv->num_chips < 2);
+
     ram_per_chip = (machine->ram_size - 1 * GiB) / (pnv->num_chips - 1);
     return chip_id == 0 ? 1 * GiB : QEMU_ALIGN_DOWN(ram_per_chip, 1 * MiB);
 }