Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge branch 'for-6.19/cxl-elc' into cxl-for-next
- Add extended linear cache size sysfs attribute.
- Adjust failure emission of extended linear cache detection in cxl_acpi.
+61
-26
+10
-1
Documentation/ABI/testing/sysfs-bus-cxl
+10
-1
Documentation/ABI/testing/sysfs-bus-cxl
···
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changed, only freed by writing 0. The kernel makes no guarantees
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that data is maintained over an address space freeing event, and
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there is no guarantee that a free followed by an allocate
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-
results in the same address being allocated.
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+
results in the same address being allocated. If extended linear
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cache is present, the size indicates extended linear cache size
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plus the CXL region size.
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What: /sys/bus/cxl/devices/regionZ/extended_linear_cache_size
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Date: October, 2025
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KernelVersion: v6.19
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Contact: linux-cxl@vger.kernel.org
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Description:
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(RO) The size of extended linear cache, if there is an extended
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linear cache. Otherwise the attribute will not be visible.
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What: /sys/bus/cxl/devices/regionZ/mode
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Date: January, 2023
+7
-10
drivers/cxl/acpi.c
+7
-10
drivers/cxl/acpi.c
···
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rc = hmat_get_extended_linear_cache_size(&res, nid, &cache_size);
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if (rc)
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-
return rc;
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+
return 0;
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/*
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* The cache range is expected to be within the CFMWS.
···
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int rc;
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rc = cxl_acpi_set_cache_size(cxlrd);
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-
if (!rc)
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return;
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-
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-
if (rc != -EOPNOTSUPP) {
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+
if (rc) {
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/*
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* Failing to support extended linear cache region resize does not
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+
* Failing to retrieve extended linear cache region resize does not
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* prevent the region from functioning. Only causes cxl list showing
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* incorrect region size.
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*/
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dev_warn(cxlrd->cxlsd.cxld.dev.parent,
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"Extended linear cache calculation failed rc:%d\n", rc);
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-
}
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"Extended linear cache retrieval failed rc:%d\n", rc);
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-
/* Ignoring return code */
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-
cxlrd->cache_size = 0;
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+
/* Ignoring return code */
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cxlrd->cache_size = 0;
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+
}
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}
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DEFINE_FREE(put_cxlrd, struct cxl_root_decoder *,
+44
-15
drivers/cxl/core/region.c
+44
-15
drivers/cxl/core/region.c
···
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}
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static DEVICE_ATTR_RW(commit);
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-
static umode_t cxl_region_visible(struct kobject *kobj, struct attribute *a,
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int n)
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-
{
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struct device *dev = kobj_to_dev(kobj);
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struct cxl_region *cxlr = to_cxl_region(dev);
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-
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/*
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* Support tooling that expects to find a 'uuid' attribute for all
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* regions regardless of mode.
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*/
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if (a == &dev_attr_uuid.attr && cxlr->mode != CXL_PARTMODE_PMEM)
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return 0444;
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return a->mode;
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-
}
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-
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static ssize_t interleave_ways_show(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
···
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}
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static DEVICE_ATTR_RW(size);
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+
static ssize_t extended_linear_cache_size_show(struct device *dev,
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struct device_attribute *attr,
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+
char *buf)
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{
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struct cxl_region *cxlr = to_cxl_region(dev);
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struct cxl_region_params *p = &cxlr->params;
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ssize_t rc;
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+
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ACQUIRE(rwsem_read_intr, rwsem)(&cxl_rwsem.region);
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if ((rc = ACQUIRE_ERR(rwsem_read_intr, &rwsem)))
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return rc;
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return sysfs_emit(buf, "%#llx\n", p->cache_size);
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}
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static DEVICE_ATTR_RO(extended_linear_cache_size);
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+
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static struct attribute *cxl_region_attrs[] = {
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&dev_attr_uuid.attr,
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&dev_attr_commit.attr,
···
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&dev_attr_resource.attr,
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&dev_attr_size.attr,
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&dev_attr_mode.attr,
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+
&dev_attr_extended_linear_cache_size.attr,
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NULL,
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};
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+
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static umode_t cxl_region_visible(struct kobject *kobj, struct attribute *a,
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+
int n)
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+
{
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struct device *dev = kobj_to_dev(kobj);
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struct cxl_region *cxlr = to_cxl_region(dev);
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+
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/*
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* Support tooling that expects to find a 'uuid' attribute for all
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+
* regions regardless of mode.
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+
*/
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if (a == &dev_attr_uuid.attr && cxlr->mode != CXL_PARTMODE_PMEM)
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return 0444;
787
+
788
+
/*
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* Don't display extended linear cache attribute if there is no
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* extended linear cache.
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+
*/
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if (a == &dev_attr_extended_linear_cache_size.attr &&
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+
cxlr->params.cache_size == 0)
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return 0;
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+
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+
return a->mode;
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+
}
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static const struct attribute_group cxl_region_group = {
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.attrs = cxl_region_attrs,
···
3604
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dev_warn(cxlmd->dev.parent,
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"Extended linear cache calculation failed rc:%d\n", rc);
3606
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}
3582
+
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+
rc = sysfs_update_group(&cxlr->dev.kobj, &cxl_region_group);
3584
+
if (rc)
3585
+
return rc;
3607
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rc = insert_resource(cxlrd->res, res);
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if (rc) {