On 10/29/21 15:57, Dmitrii Shcherbakov wrote:
This patch set improves edge case testing: * The parser is now more strict about checking boundary conditions when parsing fields: an invalid field length is a possibility which is now being accounted for; * The parser will now make sure that RV and RW fields are the last in their section by making sure that no more data is left to read after those; * The RW field in the read-write section is not considered a VPD format violation even though it is a violation of the spec since it does not prevent Libvirt from parsing valid data for presenting it to a user. This is a policy decision made by Libvirt in favor of usability with hardware that does not strictly follow the PCI/PCIe VPD spec.
Libvirtd in a Power9 host is throwing these warnings on every startup: Running 'src/libvirtd'... 2021-10-31 23:56:40.637+0000: 140468: info : libvirt version: 7.9.0 2021-10-31 23:56:40.637+0000: 140468: info : hostname: ltc-boston118 2021-10-31 23:56:40.804+0000: 140520: error : virPCIVPDParseVPDLargeResourceFields:588 : internal error: VPD-W does not contain the mandatory RW field 2021-10-31 23:56:40.808+0000: 140520: error : virPCIVPDParseVPDLargeResourceFields:588 : internal error: VPD-W does not contain the mandatory RW field 2021-10-31 23:56:40.813+0000: 140520: error : virPCIVPDParseVPDLargeResourceFields:588 : internal error: VPD-W does not contain the mandatory RW field 2021-10-31 23:56:40.817+0000: 140520: error : virPCIVPDParseVPDLargeResourceFields:588 : internal error: VPD-W does not contain the mandatory RW field With this series the warnings are now gone. All patches: Tested-by: Daniel Henrique Barboza <danielhb413@xxxxxxxxx>
Invalid field values are now skipped instead of halting further parsing completely. Some vendors use 0xFF as placeholders in VPD-W since those values do not correspond to printable ASCII characters, they will be discarded, however, parsing will continue beyond that point. Also, it turns out that some vendors use printable ASCII characters not present in the alphanumeric range. Following a mailing list discussion Libvirt will accept printable ASCII characters to avoid cases where useful data is discarded. https://listman.redhat.com/archives/libvir-list/2021-October/msg01043.html Higher-level software needs to account for this character set and act accordingly. For example, the outcome of this is that one may get "N/A" as a value for a serial number that is supposed to be unique, however, there is no way for Libvirt to validate serial number uniqueness anyway even if it was a different character sequence. https://gitlab.com/dmitriis/libvirt/-/pipelines/398517951 (x86_64 only, have not set up arch-specific runners yet and over the limit of what gitlab provides) Dmitrii Shcherbakov (3): PCI VPD: handle additional edge cases PCI VPD: Skip fields with invalid values PCI VPD: Fix a wrong return code in a test case src/util/virpcivpd.c | 63 +++++++--- tests/virpcivpdtest.c | 263 ++++++++++++++++++++++++++++++++++++++++-- 2 files changed, 296 insertions(+), 30 deletions(-)
