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| author | Christoph Hellwig <hch@lst.de> | 2026-06-11 16:06:47 +0200 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2026-06-12 10:40:35 -0600 |
| commit | e8dcf2d142bd720c8334233ad6cfdf00f0e76b7f (patch) | |
| tree | fefe7d557847f9db46119ac89b8c14483f2d645b /Documentation/block | |
| parent | d39a63ead381c7ee93cd938ea2d759c17343b522 (diff) | |
| download | linux-next-e8dcf2d142bd720c8334233ad6cfdf00f0e76b7f.tar.gz linux-next-e8dcf2d142bd720c8334233ad6cfdf00f0e76b7f.zip | |
block: add configurable error injection
Add a new block error injection interface that allows to inject specific
status code for specific ranges.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@kernel.org>
Reviewed-by: Md Haris Iqbal <haris.iqbal@linux.dev>
Link: https://patch.msgid.link/20260611140703.2401204-5-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'Documentation/block')
| -rw-r--r-- | Documentation/block/error-injection.rst | 59 | ||||
| -rw-r--r-- | Documentation/block/index.rst | 1 |
2 files changed, 60 insertions, 0 deletions
diff --git a/Documentation/block/error-injection.rst b/Documentation/block/error-injection.rst new file mode 100644 index 000000000000..81f31af82e65 --- /dev/null +++ b/Documentation/block/error-injection.rst @@ -0,0 +1,59 @@ +.. SPDX-License-Identifier: GPL-2.0 + +============================ +Configurable Error Injection +============================ + +Overview +-------- + +Configurable error injection allows injecting specific block layer status codes +for sector ranges of a block device. Errors can be injected unconditionally, or +with a given probability. + +To use configurable error injection, CONFIG_BLK_ERROR_INJECTION must be enabled. + +The only interface is the error_injection debugfs file, which is created for +each registered gendisk. Writes to this file are used to create or delete rules +and reads return a list of the current error injection sites. + +Options +------- + +The following options specify the operations: + +=================== ======================================================= +add add a new rule +removeall remove all existing rules +=================== ======================================================= + +The following options specify the details of the rule for the add operation: + +=================== ======================================================= +op=<string> block layer operation this rule applies to. This uses + the XYZ for each REQ_OP_XYZ operation, e.g. READ, WRITE + or DISCARD. Mandatory. +status=<string> Status to return. This uses XYZ for each BLK_STS_XYZ + code, e.g. IOERR or MEDIUM. Mandatory. +start=<number> First block layer sector the rule applies to. + Optional, defaults to 0. +nr_sectors=<number> Number of sectors this rule applies. + Optional, defaults to the remainder of the device. +chance=<number> Only return a failure with a likelihood of 1/chance. + Optional, defaults to 1 (always). +=================== ======================================================= + +Example +------- + +Return BLK_STS_IOERR for one in 10 reads of sector 0 of /dev/nvme0n1: + + $ echo 'add,op=READ,start=0,status=IOERR,chance=10' > /sys/kernel/debug/block/nvme0n1/error_injection + +Return BLK_STS_MEDIUM for every write to /dev/nvme0n1: + + $ echo 'add,op=WRITE,start=0,status=MEDIUM' > /sys/kernel/debug/block/nvme0n1/error_injection + +Remove all rules for /dev/nvme0n1: + + $ echo 'removeall' > /sys/kernel/debug/block/nvme0n1/error_injection diff --git a/Documentation/block/index.rst b/Documentation/block/index.rst index 9fea696f9daa..bfa1bbd31ddf 100644 --- a/Documentation/block/index.rst +++ b/Documentation/block/index.rst @@ -22,3 +22,4 @@ Block switching-sched writeback_cache_control ublk + error-injection |