Re: [Qemu-stable] [PATCH v3] ivshmem: Fix 64 bit memory bar configuration

[Paolo Bonzini]

On 18/11/2016 16:27, Michael S. Tsirkin wrote:
> On Thu, Nov 17, 2016 at 08:31:03PM +0800, Zhuangyanying wrote:
>> From: Zhuang Yanying <address@hidden>
>>
>>     Device ivshmem property use64=0 is designed to make the device
>>     expose a 32 bit shared memory BAR instead of 64 bit one.  The
>>     default is a 64 bit BAR, except pc-1.2 and older retain a 32 bit
>>     BAR.  A 32 bit BAR can support only up to 1 GiB of shared memory.
>>
>>     This worked as designed until commit 5400c02 accidentally flipped
>>     its sense: since then, we misinterpret use64=0 as use64=1 and vice
>>     versa.  Worse, the default got flipped as well.  Devices
>>     ivshmem-plain and ivshmem-doorbell are not affected.
>>
>>     Fix by restoring the test of IVShmemState member not_legacy_32bit
>>     that got messed up in commit 5400c02.  Also update its
>>     initialization for devices ivhsmem-plain and ivshmem-doorbell.
>>     Without that, they'd regress to 32 bit BARs.
>>
>>     Cc: address@hidden
>>     Signed-off-by: Zhuang Yanying <address@hidden>
>>     Reviewed-by: Gonglei <address@hidden>
>>     Reviewed-by: Marc-André Lureau <address@hidden>
> 
> This is UTF-8 encoded, but your mail header says
> Content-Transfer-Encoding: 8bit
> so git am fails to apply this.

The problematic header is more likely

Content-Type: text/plain; charset=iso-8859-1

Paolo

> 
> 
>> ---
>>  hw/misc/ivshmem.c | 4 +++-
>>  1 file changed, 3 insertions(+), 1 deletion(-)
>>
>> diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c
>> index 230e51b..abeaf3d 100644
>> --- a/hw/misc/ivshmem.c
>> +++ b/hw/misc/ivshmem.c
>> @@ -858,7 +858,7 @@ static void ivshmem_common_realize(PCIDevice *dev, Error 
>> **errp)
>>      pci_register_bar(dev, 0, PCI_BASE_ADDRESS_SPACE_MEMORY,
>>                       &s->ivshmem_mmio);
>>  
>> -    if (!s->not_legacy_32bit) {
>> +    if (s->not_legacy_32bit) {
>>          attr |= PCI_BASE_ADDRESS_MEM_TYPE_64;
>>      }
>>  
>> @@ -1045,6 +1045,7 @@ static void ivshmem_plain_init(Object *obj)
>>                               ivshmem_check_memdev_is_busy,
>>                               OBJ_PROP_LINK_UNREF_ON_RELEASE,
>>                               &error_abort);
>> +    s->not_legacy_32bit = 1;
>>  }
>>  
>>  static void ivshmem_plain_realize(PCIDevice *dev, Error **errp)
>> @@ -1116,6 +1117,7 @@ static void ivshmem_doorbell_init(Object *obj)
>>  
>>      s->features |= (1 << IVSHMEM_MSI);
>>      s->legacy_size = SIZE_MAX;  /* whatever the server sends */
>> +    s->not_legacy_32bit = 1;
>>  }
>>  
>>  static void ivshmem_doorbell_realize(PCIDevice *dev, Error **errp)
>> -- 
>> 1.8.3.1
>>