linux-stable.git/tools/testing/cxl, branch linux-6.6.y

cxl/test: Add check after kzalloc() memory in alloc_mock_res()

2026-07-24T14:03:11+00:00

[ Upstream commit dfe28c8592538152e9611341dae6f7be1735b3f1 ]

alloc_mock_res() calls kzalloc() without checking the return value.
Add scope based resource management to deal with the allocated memory
cleanly.

Reported-by: sashiko-bot
Fixes: 67dcdd4d3b83 ("tools/testing/cxl: Introduce a mocked-up CXL port hierarchy")
Reviewed-by: Alison Schofield 
Link: https://patch.msgid.link/20260611230305.197390-1-dave.jiang@intel.com
Signed-off-by: Dave Jiang 
Signed-off-by: Sasha Levin

cxl/test: Zero out LSA backing memory to avoid leaking to user

2026-07-24T14:03:10+00:00

[ Upstream commit 60f065dbaf46e65830da62a0041761f0c039e086 ]

Memory through vmalloc() is not zeroed out. When this memory is copied
into output payload, it leaks memory content to user. Use vzalloc()
instead to zero out the memory.

Suggested-by: sashiko-bot
Link: https://lore.kernel.org/linux-cxl/20260605173146.2B9A31F00893@smtp.kernel.org/
Fixes: 7d3eb23c4ccf ("tools/testing/cxl: Introduce a mock memory device + driver")
Reviewed-by: Alison Schofield 
Link: https://patch.msgid.link/20260605184426.4070913-1-dave.jiang@intel.com
Signed-off-by: Dave Jiang 
Signed-off-by: Sasha Levin

cxl/test: Fix integer overflow in mock LSA bounds checks

2026-07-24T14:03:10+00:00

[ Upstream commit 81eafcada109b653977c4dfbd2b6a72470025a01 ]

Pre-existing issue discovered by sashiko-bot.

mock_get_lsa() and mock_set_lsa() validate the requested LSA range with
"offset + length > LSA_SIZE". Both offset and length are u32 and, in
mock_get_lsa(), both are taken directly from the user-supplied payload.
The addition is evaluated modulo 2^32, so a large offset combined with a
small length wraps around and passes the check.

Rewrite the checks to first bound offset, then compare length against the
remaining LSA size.

Suggested-by: sashiko-bot
Fixes: 7d3eb23c4ccf ("tools/testing/cxl: Introduce a mock memory device + driver")
Link: https://lore.kernel.org/linux-cxl/20260605143748.235271F00893@smtp.kernel.org/
Assisted-by: Claude:claude-opus-4-8
Reviewed-by: Alison Schofield 
Signed-off-by: Dave Jiang 
Signed-off-by: Sasha Levin

cxl/port: Fix use-after-free, permit out-of-order decoder shutdown

2024-11-08T15:28:24+00:00

commit 101c268bd2f37e965a5468353e62d154db38838e upstream.

In support of investigating an initialization failure report [1],
cxl_test was updated to register mock memory-devices after the mock
root-port/bus device had been registered. That led to cxl_test crashing
with a use-after-free bug with the following signature:

    cxl_port_attach_region: cxl region3: cxl_host_bridge.0:port3 decoder3.0 add: mem0:decoder7.0 @ 0 next: cxl_switch_uport.0 nr_eps: 1 nr_targets: 1
    cxl_port_attach_region: cxl region3: cxl_host_bridge.0:port3 decoder3.0 add: mem4:decoder14.0 @ 1 next: cxl_switch_uport.0 nr_eps: 2 nr_targets: 1
    cxl_port_setup_targets: cxl region3: cxl_switch_uport.0:port6 target[0] = cxl_switch_dport.0 for mem0:decoder7.0 @ 0
1)  cxl_port_setup_targets: cxl region3: cxl_switch_uport.0:port6 target[1] = cxl_switch_dport.4 for mem4:decoder14.0 @ 1
    [..]
    cxld_unregister: cxl decoder14.0:
    cxl_region_decode_reset: cxl_region region3:
    mock_decoder_reset: cxl_port port3: decoder3.0 reset
2)  mock_decoder_reset: cxl_port port3: decoder3.0: out of order reset, expected decoder3.1
    cxl_endpoint_decoder_release: cxl decoder14.0:
    [..]
    cxld_unregister: cxl decoder7.0:
3)  cxl_region_decode_reset: cxl_region region3:
    Oops: general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6bc3: 0000 [#1] PREEMPT SMP PTI
    [..]
    RIP: 0010:to_cxl_port+0x8/0x60 [cxl_core]
    [..]
    Call Trace:
     
     cxl_region_decode_reset+0x69/0x190 [cxl_core]
     cxl_region_detach+0xe8/0x210 [cxl_core]
     cxl_decoder_kill_region+0x27/0x40 [cxl_core]
     cxld_unregister+0x5d/0x60 [cxl_core]

At 1) a region has been established with 2 endpoint decoders (7.0 and
14.0). Those endpoints share a common switch-decoder in the topology
(3.0). At teardown, 2), decoder14.0 is the first to be removed and hits
the "out of order reset case" in the switch decoder. The effect though
is that region3 cleanup is aborted leaving it in-tact and
referencing decoder14.0. At 3) the second attempt to teardown region3
trips over the stale decoder14.0 object which has long since been
deleted.

The fix here is to recognize that the CXL specification places no
mandate on in-order shutdown of switch-decoders, the driver enforces
in-order allocation, and hardware enforces in-order commit. So, rather
than fail and leave objects dangling, always remove them.

In support of making cxl_region_decode_reset() always succeed,
cxl_region_invalidate_memregion() failures are turned into warnings.
Crashing the kernel is ok there since system integrity is at risk if
caches cannot be managed around physical address mutation events like
CXL region destruction.

A new device_for_each_child_reverse_from() is added to cleanup
port->commit_end after all dependent decoders have been disabled. In
other words if decoders are allocated 0->1->2 and disabled 1->2->0 then
port->commit_end only decrements from 2 after 2 has been disabled, and
it decrements all the way to zero since 1 was disabled previously.

Link: http://lore.kernel.org/20241004212504.1246-1-gourry@gourry.net [1]
Cc: stable@vger.kernel.org
Fixes: 176baefb2eb5 ("cxl/hdm: Commit decoder state to hardware")
Reviewed-by: Jonathan Cameron 
Cc: Greg Kroah-Hartman 
Cc: Davidlohr Bueso 
Cc: Dave Jiang 
Cc: Alison Schofield 
Cc: Ira Weiny 
Cc: Zijun Hu 
Signed-off-by: Dan Williams 
Reviewed-by: Ira Weiny 
Link: https://patch.msgid.link/172964782781.81806.17902885593105284330.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Ira Weiny 
Signed-off-by: Greg Kroah-Hartman

cxl/region: check interleave capability

2024-07-05T07:34:07+00:00

[ Upstream commit 84328c5acebc10c8cdcf17283ab6c6d548885bfc ]

Since interleave capability is not verified, if the interleave
capability of a target does not match the region need, committing decoder
should have failed at the device end.

In order to checkout this error as quickly as possible, driver needs
to check the interleave capability of target during attaching it to
region.

Per CXL specification r3.1(8.2.4.20.1 CXL HDM Decoder Capability Register),
bits 11 and 12 indicate the capability to establish interleaving in 3, 6,
12 and 16 ways. If these bits are not set, the target cannot be attached to
a region utilizing such interleave ways.

Additionally, bits 8 and 9 represent the capability of the bits used for
interleaving in the address, Linux tracks this in the cxl_port
interleave_mask.

Per CXL specification r3.1(8.2.4.20.13 Decoder Protection):
  eIW means encoded Interleave Ways.
  eIG means encoded Interleave Granularity.

  in HPA:
  if eIW is 0 or 8 (interleave ways: 1, 3), all the bits of HPA are used,
  the interleave bits are none, the following check is ignored.

  if eIW is less than 8 (interleave ways: 2, 4, 8, 16), the interleave bits
  start at bit position eIG + 8 and end at eIG + eIW + 8 - 1.

  if eIW is greater than 8 (interleave ways: 6, 12), the interleave bits
  start at bit position eIG + 8 and end at eIG + eIW - 1.

  if the interleave mask is insufficient to cover the required interleave
  bits, the target cannot be attached to the region.

Fixes: 384e624bb211 ("cxl/region: Attach endpoint decoders")
Signed-off-by: Yao Xingtao 
Reviewed-by: Dan Williams 
Reviewed-by: Jonathan Cameron 
Link: https://patch.msgid.link/20240614084755.59503-2-yaoxt.fnst@fujitsu.com
Signed-off-by: Dave Jiang 
Signed-off-by: Sasha Levin

cxl/test: Add missing vmalloc.h for tools/testing/cxl/test/mem.c

2024-06-21T12:38:26+00:00

[ Upstream commit d55510527153d17a3af8cc2df69c04f95ae1350d ]

tools/testing/cxl/test/mem.c uses vmalloc() and vfree() but does not
include linux/vmalloc.h. Kernel v6.10 made changes that causes the
currently included headers not depend on vmalloc.h and therefore
mem.c can no longer compile. Add linux/vmalloc.h to fix compile
issue.

  CC [M]  tools/testing/cxl/test/mem.o
tools/testing/cxl/test/mem.c: In function ‘label_area_release’:
tools/testing/cxl/test/mem.c:1428:9: error: implicit declaration of function ‘vfree’; did you mean ‘kvfree’? [-Werror=implicit-function-declaration]
 1428 |         vfree(lsa);
      |         ^~~~~
      |         kvfree
tools/testing/cxl/test/mem.c: In function ‘cxl_mock_mem_probe’:
tools/testing/cxl/test/mem.c:1466:22: error: implicit declaration of function ‘vmalloc’; did you mean ‘kmalloc’? [-Werror=implicit-function-declaration]
 1466 |         mdata->lsa = vmalloc(LSA_SIZE);
      |                      ^~~~~~~
      |                      kmalloc

Fixes: 7d3eb23c4ccf ("tools/testing/cxl: Introduce a mock memory device + driver")
Reviewed-by: Dan Williams 
Reviewed-by: Alison Schofield 
Link: https://lore.kernel.org/r/20240528225551.1025977-1-dave.jiang@intel.com
Signed-off-by: Dave Jiang 
Signed-off-by: Sasha Levin

cxl: Add cxl_num_decoders_committed() usage to cxl_test

2024-01-10T16:17:02+00:00

commit e05501e8a84eee4f819f31b9ce663bddd01b3b69 upstream.

Commit 458ba8189cb4 ("cxl: Add cxl_decoders_committed() helper") missed the
conversion for cxl_test. Add usage of cxl_num_decoders_committed() to
replace the open coding.

Suggested-by: Alison Schofield 
Signed-off-by: Dave Jiang 
Reviewed-by: Fan Ni 
Link: https://lore.kernel.org/r/169929160525.824083.11813222229025394254.stgit@djiang5-mobl3
Signed-off-by: Dan Williams 
Signed-off-by: Greg Kroah-Hartman

cxl/region: Fix x1 root-decoder granularity calculations

2023-11-28T17:20:07+00:00

commit 98a04c7aced2b43b3ac4befe216c4eecc7257d4b upstream.

Root decoder granularity must match value from CFWMS, which may not
be the region's granularity for non-interleaved root decoders.

So when calculating granularities for host bridge decoders, use the
region's granularity instead of the root decoder's granularity to ensure
the correct granularities are set for the host bridge decoders and any
downstream switch decoders.

Test configuration is 1 host bridge * 2 switches * 2 endpoints per switch.

Region created with 2048 granularity using following command line:

cxl create-region -m -d decoder0.0 -w 4 mem0 mem2 mem1 mem3 \
		  -g 2048 -s 2048M

Use "cxl list -PDE | grep granularity" to get a view of the granularity
set at each level of the topology.

Before this patch:
        "interleave_granularity":2048,
        "interleave_granularity":2048,
    "interleave_granularity":512,
        "interleave_granularity":2048,
        "interleave_granularity":2048,
    "interleave_granularity":512,
"interleave_granularity":256,

After:
        "interleave_granularity":2048,
        "interleave_granularity":2048,
    "interleave_granularity":4096,
        "interleave_granularity":2048,
        "interleave_granularity":2048,
    "interleave_granularity":4096,
"interleave_granularity":2048,

Fixes: 27b3f8d13830 ("cxl/region: Program target lists")
Cc: 
Signed-off-by: Jim Harris 
Link: https://lore.kernel.org/r/169824893473.1403938.16110924262989774582.stgit@bgt-140510-bm03.eng.stellus.in
[djbw: fixup the prebuilt cxl_test region]
Signed-off-by: Dan Williams 
Signed-off-by: Greg Kroah-Hartman

cxl/pci: Clarify devm host for memdev relative setup

2023-11-20T10:59:30+00:00

[ Upstream commit f29a824b0b6710328a78b018de3c2cfa9db65876 ]

It is all too easy to get confused about @dev usage in the CXL driver
stack. Before adding a new cxl_pci_probe() setup operation that has a
devm lifetime dependent on @cxlds->dev binding, but also references
@cxlmd->dev, and prints messages, rework the devm_cxl_add_memdev() and
cxl_memdev_setup_fw_upload() function signatures to make this
distinction explicit. I.e. pass in the devm context as an @host argument
rather than infer it from other objects.

This is in preparation for adding a devm_cxl_sanitize_setup_notifier().

Note the whitespace fixup near the change of the devm_cxl_add_memdev()
signature. That uncaught typo originated in the patch that added
cxl_memdev_security_init().

Reviewed-by: Jonathan Cameron 
Reviewed-by: Ira Weiny 
Reviewed-by: Dave Jiang 
Signed-off-by: Dan Williams 
Stable-dep-of: 5f2da1971446 ("cxl/pci: Fix sanitize notifier setup")
Signed-off-by: Sasha Levin

tools/testing/cxl: Remove unused SZ_512G macro

2023-07-21T05:35:22+00:00

SZ_512G macro has become useless since commit b2f3b74e1072
("tools/testing/cxl: Move cxl_test resources to the top of memory")
so remove it directly.

Signed-off-by: Xiao Yang 
Link: https://lore.kernel.org/r/20230719163103.3392-1-yangx.jy@fujitsu.com
Reviewed-by: Dave Jiang 
Signed-off-by: Vishal Verma