linux-toradex.git/drivers/cxl/core/features.c, branch v6.18-rc4

cxl/features: Add check for no entries in cxl_feature_info

2025-10-13T20:47:49+00:00

cxl EDAC calls cxl_feature_info() to get the feature information and
if the hardware has no Features support, cxlfs may be passed in as
NULL.

[   51.957498] BUG: kernel NULL pointer dereference, address: 0000000000000008
[   51.965571] #PF: supervisor read access in kernel mode
[   51.971559] #PF: error_code(0x0000) - not-present page
[   51.977542] PGD 17e4f6067 P4D 0
[   51.981384] Oops: Oops: 0000 [#1] SMP NOPTI
[   51.986300] CPU: 49 UID: 0 PID: 3782 Comm: systemd-udevd Not tainted 6.17.0dj
test+ #64 PREEMPT(voluntary)
[   51.997355] Hardware name: 
[   52.009790] RIP: 0010:cxl_feature_info+0xa/0x80 [cxl_core]

Add a check for cxlfs before dereferencing it and return -EOPNOTSUPP if
there is no cxlfs created due to no hardware support.

Fixes: eb5dfcb9e36d ("cxl: Add support to handle user feature commands for set feature")
Reviewed-by: Davidlohr Bueso 
Reviewed-by: Alison Schofield 
Signed-off-by: Dave Jiang

cxl: fix return value in cxlctl_validate_set_features()

2025-06-09T16:18:15+00:00

The cxlctl_validate_set_features() function is type bool.  It's supposed
to return true for valid requests and false for invalid.  However, this
error path returns ERR_PTR(-EINVAL) which is true when it was intended to
return false.

The incorrect return will result in kernel failing to prevent a
incorrect op_size passed in from userspace to be detected.

[ dj: Add user impact to commit log ]

Fixes: f76e0bbc8bc3 ("cxl: Update prototype of function get_support_feature_info()")
Signed-off-by: Dan Carpenter 
Reviewed-by: Ira Weiny 
Link: https://patch.msgid.link/aDbFPSCujpJLY1if@stanley.mountain
Signed-off-by: Dave Jiang

Merge branch 'for-6.16/cxl-features-ras' into cxl-for-next

2025-05-23T20:26:24+00:00

Add CXL RAS Features support. Features include "patrol scrub control",
"error check scrub", "perform maintenance", and "memory sparing". This
support connects the RAS Featurs to EDAC.

cxl: Update prototype of function get_support_feature_info()

2025-05-23T20:24:00+00:00

Add following changes to function get_support_feature_info()
1. Make generic to share between cxl-fwctl and cxl-edac paths.
2. Rename get_support_feature_info() to cxl_feature_info()
3. Change parameter const struct fwctl_rpc_cxl *rpc_in to
   const uuid_t *uuid.

Suggested-by: Dan Williams 
Reviewed-by: Dave Jiang 
Reviewed-by: Jonathan Cameron 
Signed-off-by: Shiju Jose 
Reviewed-by: Fan Ni 
Reviewed-by: Alison Schofield 
Acked-by: Dan Williams 
Link: https://patch.msgid.link/20250521124749.817-3-shiju.jose@huawei.com
Signed-off-by: Dave Jiang

cxl/features: Remove the inline specifier from to_cxlfs()

2025-05-22T14:39:01+00:00

to_cxlfs() was declared 'inline' in the header but only defined in
drivers/cxl/core/features.c. This has worked because features.c was
the only file using the function and the definition happened to be
available in the same compilation unit.

However, in preparation for a second .c file using the header and
needing to call the function, the inline specifier became an issue.
Sparse flagged the declaration as invalid since 'inline' requires a
visible definition at the point of use.

Defining the function in the header was considered but rejected, as
it depends on internal symbols not visible at that level.

Remove the inline specifier to correct the linkage violation.

Signed-off-by: Alison Schofield 
Reviewed-by: Dave Jiang 
Reviewed-by: Jonathan Cameron 
Reviewed-by: Shiju Jose 
Link: https://patch.msgid.link/20250521233625.1745849-1-alison.schofield@intel.com
Signed-off-by: Dave Jiang

cxl/feature: Remove redundant code of get supported features

2025-05-19T15:58:04+00:00

In cxlctl_get_supported_features(), there is a code block that handles
the case where the requested is equal to 0. But the code following the
code block can also handle this situation. So the code block is not
needed.

Signed-off-by: Li Ming 
Reviewed-by: Jonathan Cameron 
Reviewed-by: Dave Jiang 
Link: https://patch.msgid.link/20250516143220.35302-1-ming.li@zohomail.com
Signed-off-by: Dave Jiang

Documentation: Update the CXL Maturity Map

2025-05-15T23:34:26+00:00

Changes for extended-linear cache, hetero-interleave, and HPA->DPA
address translation.

Signed-off-by: Alison Schofield 
Reviewed-by: Dave Jiang 
Link: https://patch.msgid.link/20250512214225.1389484-1-alison.schofield@intel.com
Signed-off-by: Dave Jiang

cxl: Sync up the driver-api/cxl documentation

2025-05-13T22:12:15+00:00

pmem.c regs.c mbox.c identifiers were missing. Add them to
memory-devices.rst following their respective DOC comment includes.

Two acpi.c identifiers were available, but not used in kernel-doc's:
1) Add add_cxl_resources to memory-devices.rst and fix up the Sphinx
complaint on the ascii art by escaping it.
2) Add cxl_acpi_evaluate_qtg_dsm to access-coordinates.rst.

core/features.c is new. Add a "DOC: cxl features" comment to the
source and identifiers to memory_devices.rst.

Signed-off-by: Alison Schofield 
Reviewed-by: Ira Weiny 
Link: https://patch.msgid.link/20250513215813.1419645-1-alison.schofield@intel.com
Signed-off-by: Dave Jiang

cxl: Remove always true condition for cxlctl_validate_hw_command()

2025-04-28T15:48:30+00:00

smatch warnings:
drivers/cxl/core/features.c:441 cxlctl_validate_hw_command() warn: always true condition '(scope >= 0) => (0-u32max >= 0)'

Remove the check entirely as it has no effect. Expectation is both of these
operations should be allowed for all check levels. They are read only and
have no change effects.

Reported-by: kernel test robot 
Closes: https://lore.kernel.org/oe-kbuild-all/202504041033.2HBboAZR-lkp@intel.com/
Reviewed-by: Li Ming 
Reviewed-by: Ira Weiny 
Reviewed-by: Jonathan Cameron 
Link: https://patch.msgid.link/20250404165418.3032414-1-dave.jiang@intel.com
Signed-off-by: Dave Jiang

cxl/feature: Update out_len in set feature failure case

2025-04-18T16:33:56+00:00

CXL subsystem supports userspace to configure features via fwctl
interface, it will configure features by using Set Feature command.
Whatever Set Feature succeeds or fails, CXL driver always needs to
return a structure fwctl_rpc_cxl_out to caller, and returned size is
updated in a out_len parameter. The out_len should be updated not only
when the set feature succeeds, but also when the set feature fails.

Fixes: eb5dfcb9e36d ("cxl: Add support to handle user feature commands for set feature")
Signed-off-by: Li Ming 
Reviewed-by: Dave Jiang 
Reviewed-by: Ira Weiny 
Reviewed-by: Jonathan Cameron 
Link: https://patch.msgid.link/20250410024521.514095-1-ming.li@zohomail.com
Signed-off-by: Dave Jiang