On Fri, 2010-07-30 at 09:42 -0700, Jesse Barnes wrote:

On Fri, 23 Jul 2010 14:56:28 +0100
Ben Hutchings [off-list ref] wrote:

quoted

commit 2ca1af9aa3285c6a5f103ed31ad09f7399fc65d7 "PCI: MSI: Remove
unsafe and unnecessary hardware access" changed read_msi_msg_desc() to
return the last MSI message written instead of reading it from the
device, since it may be called while the device is in a reduced
power state.

However, the pSeries platform code really does need to read messages
from the device, since they are initially written by firmware.
Therefore:
- Restore the previous behaviour of read_msi_msg_desc()
- Add new functions get_cached_msi_msg{,_desc}() which return the
  last MSI message written
- Use the new functions where appropriate

Signed-off-by: Ben Hutchings <redacted>
---
Compile-tested only.

Applied to linux-next with Michael's ack, thanks.  I hope it actually
works, I didn't see a tested-by!

I assume Stephen has been using it, otherwise his linux-next boot tests
will all have been failing. Either way he'll test it when it gets into
linux-next proper.

cheers