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authorDave Airlie <airlied@redhat.com>2026-09-26 07:57:59 +1000
committerDave Airlie <airlied@redhat.com>2026-09-26 07:58:24 +1000
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Merge tag 'drm-misc-fixes-2026-09-24' of https://gitlab.freedesktop.org/drm/misc/kernel into drm-fixesgrafted
A number of fixes: - bridge: - samsung-dsim: fix GPIO lifetime - client: Null pointer dereference fix - imagination: error handling fix, page handling fix - nouveau: fix reference leaks, double-frees, out-of-bounds accesses, use-after-frees, don't reject config without SCDC, a number of workarounds - virtio: fix memory leak, reference leaks, null pointer dereference, add pixel blend mode, cache coherency fix Signed-off-by: Dave Airlie <airlied@redhat.com> From: Maxime Ripard <self@mripard.dev> Link: https://patch.msgid.link/arU22zzqUGDEco1y@houat
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+========
+dm-delay
+========
+
+Device-Mapper's "delay" target delays reads and/or writes
+and/or flushes and optionally maps them to different devices.
+
+Arguments::
+
+ <device> <offset> <delay> [<write_device> <write_offset> <write_delay>
+ [<flush_device> <flush_offset> <flush_delay>]]
+
+Table line has to either have 3, 6 or 9 arguments:
+
+3: apply offset and delay to read, write and flush operations on device
+
+6: apply offset and delay to device, also apply write_offset and write_delay
+ to write and flush operations on optionally different write_device with
+ optionally different sector offset
+
+9: same as 6 arguments plus define flush_offset and flush_delay explicitly
+ on/with optionally different flush_device/flush_offset.
+
+Offsets are specified in sectors.
+
+Delays are specified in milliseconds.
+
+
+Example scripts
+===============
+
+::
+ #!/bin/sh
+ #
+ # Create mapped device named "delayed" delaying read, write and flush operations for 500ms.
+ #
+ dmsetup create delayed --table "0 `blockdev --getsz $1` delay $1 0 500"
+
+::
+ #!/bin/sh
+ #
+ # Create mapped device delaying write and flush operations for 400ms and
+ # splitting reads to device $1 but writes and flushes to different device $2
+ # to different offsets of 2048 and 4096 sectors respectively.
+ #
+ dmsetup create delayed --table "0 `blockdev --getsz $1` delay $1 2048 0 $2 4096 400"
+
+::
+ #!/bin/sh
+ #
+ # Create mapped device delaying reads for 50ms, writes for 100ms and flushes for 333ms
+ # onto the same backing device at offset 0 sectors.
+ #
+ dmsetup create delayed --table "0 `blockdev --getsz $1` delay $1 0 50 $2 0 100 $1 0 333"