Re: [PATCH] pci: change msi-x vector to 32bit

Eric W. Biederman
2008-08-21T20:54:26Z

Jesse Barnes <jbarnes@virtuousgeek.org> writes:

> On Friday, August 15, 2008 7:36 pm Yinghai Lu wrote:
>> we are using 28bit pci (bus/dev/fn + 12 bits) as irq number, so the
>> cache for irq number should be 32 bit too.
>>
>> Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
>> Cc: Andrew Vasquez <andrew.vasquez@qlogic.com>
>>
>> ---
>> drivers/scsi/qla2xxx/qla_def.h | 2 +-
>> include/linux/pci.h | 2 +-
>> 2 files changed, 2 insertions(+), 2 deletions(-)
>>
>> Index: linux-2.6/drivers/scsi/qla2xxx/qla_def.h
>> ===================================================================
>> --- linux-2.6.orig/drivers/scsi/qla2xxx/qla_def.h
>> +++ linux-2.6/drivers/scsi/qla2xxx/qla_def.h
>> @@ -2109,7 +2109,7 @@ struct scsi_qla_host;
>>
>> struct qla_msix_entry {
>> int have_irq;
>> - uint16_t msix_vector;
>> + uint32_t msix_vector;
>> uint16_t msix_entry;
>> };
>>
>> Index: linux-2.6/include/linux/pci.h
>> ===================================================================
>> --- linux-2.6.orig/include/linux/pci.h
>> +++ linux-2.6/include/linux/pci.h
>> @@ -730,7 +730,7 @@ enum pci_dma_burst_strategy {
>> };
>>
>> struct msix_entry {
>> - u16 vector; /* kernel uses to write allocated vector */
>> + u32 vector; /* kernel uses to write allocated vector */
>> u16 entry; /* driver uses to specify entry, OS writes */
>> };
>
> I see a lot of smoke about this, but not a clear consensus. It sounds like no
> one objects to making the MSI vector field 32 bits, but there were a lot of
> concerns about IRQ vector naming/numbering in general? And I assume this
> particular patch isn't 2.6.27 material...

There is no need for this particular patch in 2.6.27.
It is a trivial bug fix so it can go in whenever.

Mostly this is a discussion about code that should land in the 2.6.28
timeframe assuming all is well.

Eric