linux/drivers/cxl
Dan Williams 5459e186a5 cxl/port: Fix missing target list lock
cxl_port_setup_targets() modifies the ->targets[] array of a switch
decoder. target_list_show() expects to be able to emit a coherent
snapshot of that array by "holding" ->target_lock for read. The
target_lock is held for write during initialization of the ->targets[]
array, but it is not held for write during cxl_port_setup_targets().

The ->target_lock() predates the introduction of @cxl_region_rwsem. That
semaphore protects changes to host-physical-address (HPA) decode which
is precisely what writes to a switch decoder's target list affects.

Replace ->target_lock with @cxl_region_rwsem.

Now the side-effect of snapshotting a unstable view of a decoder's
target list is likely benign so the Fixes: tag is presumptive.

Fixes: 27b3f8d138 ("cxl/region: Program target lists")
Reviewed-by: Alison Schofield <alison.schofield@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2024-01-04 13:59:50 -08:00
..
core cxl/port: Fix missing target list lock 2024-01-04 13:59:50 -08:00
acpi.c cxl: Export QTG ids from CFMWS to sysfs as qos_class attribute 2023-10-27 20:48:02 -07:00
cxl.h cxl/port: Fix missing target list lock 2024-01-04 13:59:50 -08:00
cxlmem.h Merge branch 'for-6.7/cxl-rch-eh' into cxl/next 2023-10-31 10:59:00 -07:00
cxlpci.h cxl/pci: Find and register CXL PMU devices 2023-05-30 11:20:35 -07:00
Kconfig cxl: fix CONFIG_FW_LOADER dependency 2023-07-14 14:32:22 -06:00
Makefile cxl/pmem: Introduce nvdimm_security_ops with ->get_flags() operation 2022-11-30 16:30:47 -08:00
mem.c cxl/pci: Add RCH downstream port AER register discovery 2023-10-27 20:13:38 -07:00
pci.c Merge branch 'for-6.7/cxl' into cxl/next 2023-10-31 10:59:44 -07:00
pmem.c cxl/mbox: Move mailbox related driver state to its own data structure 2023-06-25 14:31:08 -07:00
pmu.h cxl/pci: Find and register CXL PMU devices 2023-05-30 11:20:35 -07:00
port.c cxl: Add support for reading CXL switch CDAT table 2023-10-27 20:48:02 -07:00
security.c Merge branch 'for-6.5/cxl-type-2' into for-6.5/cxl 2023-06-25 17:16:51 -07:00