'\" t
.\"     Title: cxl-clear-media-poison
.\"    Author: [see the "AUTHOR(S)" section]
.\" Generator: Asciidoctor 2.0.26
.\"      Date: 2026-06-30
.\"    Manual: cxl Manual
.\"    Source: cxl
.\"  Language: English
.\"
.TH "CXL\-CLEAR\-MEDIA\-POISON" "1" "2026-06-30" "cxl" "cxl Manual"
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.SH "NAME"
cxl-clear-media-poison \- Clear poison from CXL memory
.SH "SYNOPSIS"
.sp
.nf
\fIcxl clear\-media\-poison\fP <memdev> [<options>]
.fi
.br
.sp
Clear poison from a CXL memory device\(cqs 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").
.sp
To see if a device has poison that can be cleared use the \fIcxl\-list\fP command
with the \fI\-L\fP/\fI\-\-media\-errors\fP option. An example of a device that has had
poison injected at device physical address (a.k.a. "offset") 0x1000:
.sp
.if n .RS 4
.nf
.fam C
# 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"
        }
  ]
}
.fam
.fi
.if n .RE
.sp
A device physical address is required to clear poison from a CXL memdev. The
\fI\-a\fP/\fI\-\-address\fP 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:
.sp
.if n .RS 4
.nf
.fam C
# 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":[
  ]
}
.fam
.fi
.if n .RE
.sp
See the \fIinject\-media\-poison\fP command for how to inject poison into a CXL
memory device.
.sp
This command depends on the CXL debug filesystem (normally mounted at
"/sys/kernel/debug/cxl") to clear device poison.
.SH "OPTIONS"
.sp
\-a, \-\-address
.RS 4
Device physical address (DPA) to clear poison at. Address can
be specified in hex or decimal.
.RE
.sp
\-\-debug
.RS 4
Enable debug output
.RE
.SH "SEE ALSO"
.sp
cxl\-list(1)
cxl\-clear\-media\-poison(1)