linux-stable.git/tools/testing/cxl, branch linux-6.4.y

tools/testing/cxl: Fix command effects for inject/clear poison

2023-07-19T14:36:23+00:00

[ Upstream commit b46c5fa57cc60692412f616ac66ab624a941fdb3 ]

The CXL spec (3.0, section 8.2.9.8.4) Lists Inject Poison and Clear
Poison as having the effects of "Immediate Data Change". Fix this in the
mock driver so that the command effect log is populated correctly.

Fixes: 371c16101ee8 ("tools/testing/cxl: Mock the Inject Poison mailbox command")
Cc: Alison Schofield 
Cc: Dan Williams 
Reviewed-by: Alison Schofield 
Reviewed-by: Jonathan Cameron 
Reviewed-by: Dave Jiang 
Signed-off-by: Vishal Verma 
Link: https://lore.kernel.org/r/20230602-vv-fw_update-v4-2-c6265bd7343b@intel.com
Signed-off-by: Dan Williams 
Signed-off-by: Sasha Levin

Revert "cxl/port: Enable the HDM decoder capability for switch ports"

2023-07-05T17:30:30+00:00

commit 8f0220af58c3b73e9041377a23708d37600b33c1 upstream.

commit eb0764b822b9 ("cxl/port: Enable the HDM decoder capability for switch ports")

...was added on the observation of CXL memory not being accessible after
setting up a region on a "cold-plugged" device. A "cold-plugged" CXL
device is one that was not present at boot, so platform-firmware/BIOS
has no chance to set it up.

While it is true that the debug found the enable bit clear in the
host-bridge's instance of the global control register (CXL 3.0
8.2.4.19.2 CXL HDM Decoder Global Control Register), that bit is
described as:

"This bit is only applicable to CXL.mem devices and shall
return 0 on CXL Host Bridges and Upstream Switch Ports."

So it is meant to be zero, and further testing confirmed that this "fix"
had no effect on the failure. Revert it, and be more vigilant about
proposed fixes in the future. Since the original copied stable@, flag
this revert for stable@ as well.

Cc: 
Fixes: eb0764b822b9 ("cxl/port: Enable the HDM decoder capability for switch ports")
Reviewed-by: Jonathan Cameron 
Reviewed-by: Dave Jiang 
Link: https://lore.kernel.org/r/168685882012.3475336.16733084892658264991.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams 
Signed-off-by: Greg Kroah-Hartman

cxl: Move cxl_await_media_ready() to before capacity info retrieval

2023-05-18T23:43:45+00:00

Move cxl_await_media_ready() to cxl_pci probe before driver starts issuing
IDENTIFY and retrieving memory device information to ensure that the
device is ready to provide the information. Allow cxl_pci_probe() to succeed
even if media is not ready. Cache the media failure in cxlds and don't ask
the device for any media information.

The rationale for proceeding in the !media_ready case is to allow for
mailbox operations to interrogate and/or remediate the device. After
media is repaired then rebinding the cxl_pci driver is expected to
restart the capacity scan.

Suggested-by: Dan Williams 
Fixes: b39cb1052a5c ("cxl/mem: Register CXL memX devices")
Reviewed-by: Ira Weiny 
Signed-off-by: Dave Jiang 
Link: https://lore.kernel.org/r/168445310026.3251520.8124296540679268206.stgit@djiang5-mobl3
[djbw: fixup cxl_test]
Signed-off-by: Dan Williams

cxl/port: Enable the HDM decoder capability for switch ports

2023-05-18T20:18:49+00:00

Derick noticed, when testing hot plug, that hot-add behaves nominally
after a removal. However, if the hot-add is done without a prior
removal, CXL.mem accesses fail. It turns out that the original
implementation of the port driver and region programming wrongly assumed
that platform-firmware always enables the host-bridge HDM decoder
capability. Add support turning on switch-level HDM decoders in the case
where platform-firmware has not.

The implementation is careful to only arrange for the enable to be
undone if the current instance of the driver was the one that did the
enable. This is to interoperate with platform-firmware that may expect
CXL.mem to remain active after the driver is shutdown. This comes at the
cost of potentially not shutting down the enable on kexec flows, but it
is mitigated by the fact that the related HDM decoders still need to be
enabled on an individual basis.

Cc: 
Reported-by: Derick Marks 
Fixes: 54cdbf845cf7 ("cxl/port: Add a driver for 'struct cxl_port' objects")
Reviewed-by: Ira Weiny 
Link: https://lore.kernel.org/r/168437998331.403037.15719879757678389217.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams

tools/testing/cxl: Use DEFINE_STATIC_SRCU()

2023-05-13T07:16:40+00:00

Starting with commit:

95433f726301 ("srcu: Begin offloading srcu_struct fields to srcu_update")

...it is no longer possible to do:

static DEFINE_SRCU(x)

Switch to DEFINE_STATIC_SRCU(x) to fix:

tools/testing/cxl/test/mock.c:22:1: error: duplicate ‘static’
   22 | static DEFINE_SRCU(cxl_mock_srcu);
      | ^~~~~~

Reviewed-by: Dave Jiang 
Link: https://lore.kernel.org/r/168392709546.1135523.10424917245934547117.stgit@dwillia2-xfh.jf.intel.com
Signed-off-by: Dan Williams

cxl/test: Add mock test for set_timestamp

2023-04-24T18:31:02+00:00

Support the command testing in a unit-test fashion.

Reviewed-by: Ira Weiny 
Signed-off-by: Davidlohr Bueso 
Link: https://lore.kernel.org/r/20230423221231.6357-1-dave@stgolabs.net
Signed-off-by: Dan Williams

tools/testing/cxl: Require CONFIG_DEBUG_FS

2023-04-23T19:08:39+00:00

The cxl_mem driver uses debugfs to support poison inject and clear.
Add debugfs to the list of required symbols so that cxl_test can
emulate those poison operations.

Signed-off-by: Alison Schofield 
Reviewed-by: Dave Jiang 
Link: https://lore.kernel.org/r/4f3aab57fbf1cc3ccde2eb887c5d90566c8d0e90.1681874357.git.alison.schofield@intel.com
Signed-off-by: Dan Williams

tools/testing/cxl: Add a sysfs attr to test poison inject limits

2023-04-23T19:08:39+00:00

CXL devices may report a maximum number of addresses that a device
allows to be poisoned using poison injection. When cxl_test creates
mock CXL memory devices, it defaults to MOCK_INJECT_DEV_MAX==88 for
all mocked memdevs.

Add a sysfs attribute, poison_inject_max to module cxl_mock_mem so
that users can set a custom device injection limit. Fail, and return
-EBUSY, if the mock poison list is not empty.

/sys/bus/platform/drivers/cxl_mock_mem/poison_inject_max

A simple usage model is to set the attribute before running a test in
order to emulate a device's poison handling.

Signed-off-by: Alison Schofield 
Reviewed-by: Dave Jiang 
Link: https://lore.kernel.org/r/0f25b2862b90013545450222d2199e435c6cc11a.1681874357.git.alison.schofield@intel.com
Signed-off-by: Dan Williams

tools/testing/cxl: Use injected poison for get poison list

2023-04-23T19:08:39+00:00

Prior to poison inject support, the mock of 'Get Poison List'
returned a poison list containing a single mocked error record.

Following the addition of poison inject and clear support to the
mock driver, use the mock_poison_list[], rather than faking an
error record. Mock_poison_list[] list tracks the actual poison
inject and clear requests issued by userspace.

Signed-off-by: Alison Schofield 
Reviewed-by: Dave Jiang 
Link: https://lore.kernel.org/r/0f4242c81821f4982b02cb1009c22783ef66b2f1.1681874357.git.alison.schofield@intel.com
Signed-off-by: Dan Williams

tools/testing/cxl: Mock the Clear Poison mailbox command

2023-04-23T19:08:39+00:00

Mock the clear of poison by deleting the device:address entry from
the mock_poison_list[]. Behave like a real CXL device and do not fail
if the address is not in the poison list, but offer a dev_dbg()
message.

Signed-off-by: Alison Schofield 
Reviewed-by: Jonathan Cameron 
Reviewed-by: Dave Jiang 
Link: https://lore.kernel.org/r/ecf19743c6572e60971bbd078f67d520cf5bca5d.1681874357.git.alison.schofield@intel.com
Signed-off-by: Dan Williams