NAME

NAME

cxl-clear-media-poison - Clear poison from CXL memory

SYNOPSIS

cxl clear-media-poison <memdev> [<options>]

Clear poison from a CXL memory device’s memory. CXL memdevs can be specified by device name (e.g. “mem0”), device id (“X” in “memX”), or host device name (“0000:35:00.0”).

To see if a device has poison that can be cleared use the cxl-list command with the -L/–media-errors option. An example of a device that has had poison injected at device physical address (a.k.a. “offset”) 0x1000:

# cxl list -m mem0 -L -u
{
  "memdev":"mem0",
  "ram_size":"1024.00 MiB (1073.74 MB)",
  "ram_qos_class":42,
  "serial":"0x0",
  "numa_node:1,
  "host":"0000:35:00.0",
  "media_errors":[
    {
      "offset":"0x1000",
      "length":64,
      "source":"Injected"
    }
  ]
}

A device physical address is required to clear poison from a CXL memdev. The -a/–address option is used to specify the address to clear poison at. The address can be given in either decimal or hexadecimal. An example using the example device above:

# cxl clear-media-poison mem0 -a 0x1000
poison cleared at mem0:0x1000

# cxl list -m mem0 -L -u
{
  "memdev":"mem0",
  "ram_size":"1024.00 MiB (1073.74 MB)",
  "ram_qos_class":42,
  "serial":"0x0",
  "numa_node:1,
  "host":"0000:35:00.0",
  "media_errors":[
  ]
}

See the inject-media-poison command for how to inject poison into a CXL memory device.

This command depends on the CXL debug filesystem (normally mounted at “/sys/kernel/debug/cxl”) to clear device poison.

OPTIONS

-a; --address
Device physical address (DPA) to clear poison at. Address can be specified in hex or decimal.

--debug
Enable debug output

SEE ALSO

cxl-list cxl-clear-media-poison