Re: [PATCH v5 0/4] Harden HDM decoder enumeration

[Alison Schofield <alison.schofield@intel.com>]

Hi Dave,
This applies cleanly to 7.3-rc1 and cxl/next (of moments ago).
With these latest tags that Ming has offered I think it is ready to
merge as is. Please take a look.
-- Alison

On Fri, Aug 07, 2026 at 05:05:47PM -0700, Alison Schofield wrote:
> Changes in v5:
> Drop P2 of v4 as it changed what user sees in iw and ig attributes (Davidlohr)
> Renumbering: v4 P3 and P4 are now P2 and P3
> P1: Validate the target count once per port, not per decoder (Jonathan)
> P1: Move the zero-target reject back to cxl_switch_decoder_init() (Ming)
> P1: Drop the ways reset for uncommitted decoders (Jonathan, Davidlohr)
> P1: Declare cxlsd on one line (Jonathan)
> P1: Reword the CXL_HDM_DECODER0_TL_TARGETS comment (Jonathan)
> P2: Build the target IDs with put_unaligned_le32() (Jonathan)
> P2: Dropped all the tags on endian-ness patch
> P3: Commit log s/none committed/uncommitted/ (DaveJ)
> P4: New - bound switch decoder target array walks by nr_targets
> 
> Changes in v4:
> A new patch was inserted as Patch2, so now set is 4 patches.
>    Sashiko is likely to complain in Patch 1 for something fixed in
>    Patches 2 and 3, but reordering does not makes sense.
> P2: Only interpret interleave settings on committed decoders (Ming)
>     This is the newly inserted patch
> P4: Register reset w devm_add_action (Ming)
> P4: Fix up a kernel-doc comment issue (lkp)
> 
> Changes in v3:
> P1: Move zero-target reject to init_hdm_decoder() (RichardC)
> P3: Reset commit_end via a devres action after decoder teardown (RichardC)
> 
> Changes in v2:
> P1: Handle uncommitted decoders (Sashiko)
> P1: Reject switch decoders with zero targets (Sashiko)
> P1: Add in code comment clarifying target_count (Sashiko)
> P1: Update commit log
> P3: Reset commit_end on the failure path only (Sashiko)
> P3: Update commit log
> P2: No
> 
> 
> This set started as Sashiko reported cleanups. The patch added at v4 on
> Li Ming's review is dropped in v5. Davidlohr pointed out that it changes
> what interleave_ways and interleave_granularity report for an uncommitted
> decoder, and those are documented ABI. That is also the answer to Ming's
> v3 question that prompted the patch -  enumeration decodes those fields
> because userspace reads them, not because the driver needs them.
> 
> Only the first patch includes a link to the original Sashiko complaint,
> since the others did not originally appear on Lore for me to add public
> links.
> 
> Srirangan: I believe some of these patches address pre-existing issues
> Sashiko posted in reply to your reset series, but frankly, with the
> renumbering here, and the respin of your series, I no longer have 
> the exact patch to patch correlation.
> Alison Schofield (4):
>   cxl/hdm: Reject switch decoder interleave ways that overflow targets
>   cxl/hdm: Make switch decoder target parsing endian-safe
>   cxl/hdm: Restore commit_end when decoder enumeration fails
>   cxl/port: Bound switch decoder target array access by nr_targets
> 
>  drivers/cxl/core/hdm.c  | 62 +++++++++++++++++++++++++++++++++--------
>  drivers/cxl/core/port.c | 27 ++++++++++++------
>  drivers/cxl/cxl.h       |  2 ++
>  3 files changed, 72 insertions(+), 19 deletions(-)
> 
> 
> base-commit: 075b74841bd0065a3bda3440873c747938e69b68
> -- 
> 2.37.3
>