[PATCH 0/3] s390/pci: Updates to PCI insn tracing

[Gerd Bayer]

While debugging some issues, I found that insn traces for RPCIT are
lacking an indication for which PCI function translation tables needed
to be synchronized with hypervisors and/or firmware and that the 64bit
address fields are traced at odd addresses. While looking into how to
address this, I found another small oddity in that the code leading to
the RPCIT instruction was expanding the 32bit function handle to a 64bit
value for the inline assembly way too high in the call-chain.
    
So I started this small series to address these three issues:
1/3 - Insert padding into the insn trace at natural boundaries
2/3 - Pass function handle in 32bit variables as long as possible
3/3 - Introduce a RPCIT variant of insn trace - adding function handle
    
With this series applied (+ a test patch to trace RPCIT even in CC0
situations) an entry in /sys/kernel/debug/s390dbf/pci_error/hex_ascii
looks like the following (removed time-stamp and ASCII transcription,
replaced instruction address with "<IA>"):

 2 - 0001 <IA>  52 00 00 00 00 00 00 00 85 00 32 2e 00 00 00 00
                ^  ^  ^                 <--------->
                |  |  Status              function handle
                |  Condition Code
                "encoded" insn

 2 - 0001 <IA>  00 00 00 01 ff 04 90 00 00 00 00 00 00 00 10 00
                                        <--------------------->
                <--------------------->       IOVA range
                      start IOVA

I hope you'll find this useful,
Gerd

Signed-off-by: Gerd Bayer <gbayer@xxxxxxxxxxxxx>
---
Gerd Bayer (3):
      s390/pci: Adjust alignment in insn trace
      s390/pci: Use 32-bit fh outside of inline asm
      s390/pci: Add function handle to RPCIT insn trace

 arch/s390/include/asm/pci_insn.h |  2 +-
 arch/s390/pci/pci_insn.c         | 43 +++++++++++++++++++++++++++++++++-------
 drivers/iommu/s390-iommu.c       |  8 +++-----
 3 files changed, 40 insertions(+), 13 deletions(-)
---
base-commit: 602042bf29f6efde39cfb5fdd9289bf4854bc0c5
change-id: 20261007-rpcit_trcfh_upstream-3e6fa73dff1b

Best regards,
-- 
Gerd Bayer <gbayer@xxxxxxxxxxxxx>