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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-19 10:09:22 -0700
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Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted
Pull media updates from Mauro Carvalho Chehab: - v4l2-core: added ISP statistics support and per-block validation - v4l2-core: Allow unknown HDR10 white point and luminance - New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor - New codec: Milos: VPU v2.0 codec support - isp driver: gained support for Dreamchip RPPX1 ISP framework - vsp1 driver: gained support for RZ/T2H and RZ/N2H - Novalake driver: gained CVS support for new NVL hardware - dvb-core: fix feed leak on failed DMX_ADD_PID - several driver fixes, cleanups and minor improvements * tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits) media: ipu-bridge: check all DMI entries when overriding sensor rotation media: v4l2-async: avoid deleting unlinked ASC entry on link error media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement media: intel/ipu6: fix async notifier cleanup leak on parse error media: staging/ipu7: fix async notifier UAF on probe error path media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem() media: rcar-isp: Fix VSPX reference leaks media: rcar-isp: Release ISPCORE resources media: i2c: imx415: Release runtime PM reference on VBLANK error media: i2c: imx415: Return test pattern write errors media: renesas: vsp1: Declare index variables in for loop statement media: renesas: vsp1: Make reset control optional to support platforms without a reset line media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs media: nxp: imx8-isi: Add additional 32-bit RGB format support media: nxp: imx8-isi: Add 16-bit raw Bayer format support media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks media: nxp: imx8-isi: Correct color map between V4L2 and ISI ...
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+.. SPDX-License-Identifier: GPL-2.0
+
+==========
+SMC Sysctl
+==========
+
+/proc/sys/net/smc/* Variables
+=============================
+
+autocorking_size - INTEGER
+ Setting SMC auto corking size:
+ SMC auto corking is like TCP auto corking from the application's
+ perspective of view. When applications do consecutive small
+ write()/sendmsg() system calls, we try to coalesce these small writes
+ as much as possible, to lower total amount of CDC and RDMA Write been
+ sent.
+ autocorking_size limits the maximum corked bytes that can be sent to
+ the under device in 1 single sending. If set to 0, the SMC auto corking
+ is disabled.
+ Applications can still use TCP_CORK for optimal behavior when they
+ know how/when to uncork their sockets.
+
+ Default: 64K
+
+smcr_buf_type - INTEGER
+ Controls which type of sndbufs and RMBs to use in later newly created
+ SMC-R link group. Only for SMC-R.
+
+ Default: 0 (physically contiguous sndbufs and RMBs)
+
+ Possible values:
+
+ - 0 - Use physically contiguous buffers
+ - 1 - Use virtually contiguous buffers
+ - 2 - Mixed use of the two types. Try physically contiguous buffers first.
+ If not available, use virtually contiguous buffers then.
+
+smcr_testlink_time - INTEGER
+ How frequently SMC-R link sends out TEST_LINK LLC messages to confirm
+ viability, after the last activity of connections on it. Value 0 means
+ disabling TEST_LINK.
+
+ Default: 30 seconds.
+
+wmem - INTEGER
+ Initial size of send buffer used by SMC sockets.
+
+ The minimum value is 16KiB and there is no hard limit for max value, but
+ only allowed 512KiB for SMC-R and 1MiB for SMC-D.
+
+ Default: 64KiB
+
+rmem - INTEGER
+ Initial size of receive buffer (RMB) used by SMC sockets.
+
+ The minimum value is 16KiB and there is no hard limit for max value, but
+ only allowed 512KiB for SMC-R and 1MiB for SMC-D.
+
+ Default: 64KiB
+
+smcr_max_links_per_lgr - INTEGER
+ Controls the max number of links can be added to a SMC-R link group. Notice that
+ the actual number of the links added to a SMC-R link group depends on the number
+ of RDMA devices exist in the system. The acceptable value ranges from 1 to 2. Only
+ for SMC-R v2.1 and later.
+
+ Default: 2
+
+smcr_max_conns_per_lgr - INTEGER
+ Controls the max number of connections can be added to a SMC-R link group. The
+ acceptable value ranges from 16 to 255. Only for SMC-R v2.1 and later.
+
+ Default: 255
+
+smcr_max_send_wr - INTEGER
+ So-called work request buffers are SMCR link (and RDMA queue pair) level
+ resources necessary for performing RDMA operations. Since up to 255
+ connections can share a link group and thus also a link and the number
+ of the work request buffers is decided when the link is allocated,
+ depending on the workload it can be a bottleneck in a sense that threads
+ have to wait for work request buffers to become available. Before the
+ introduction of this control the maximal number of work request buffers
+ available on the send path used to be hard coded to 16. With this control
+ it becomes configurable. The acceptable range is between 2 and 2048.
+
+ Please be aware that all the buffers need to be allocated as a physically
+ continuous array in which each element is a single buffer and has the size
+ of SMC_WR_BUF_SIZE (48) bytes. If the allocation fails, we keep retrying
+ with half of the buffer count until it is either successful or (unlikely)
+ we dip below the old hard coded value which is 16 where we give up much
+ like before having this control.
+
+ Default: 16
+
+smcr_max_recv_wr - INTEGER
+ So-called work request buffers are SMCR link (and RDMA queue pair) level
+ resources necessary for performing RDMA operations. Since up to 255
+ connections can share a link group and thus also a link and the number
+ of the work request buffers is decided when the link is allocated,
+ depending on the workload it can be a bottleneck in a sense that threads
+ have to wait for work request buffers to become available. Before the
+ introduction of this control the maximal number of work request buffers
+ available on the receive path used to be hard coded to 48. With this control
+ it becomes configurable. The acceptable range is between 2 and 2048.
+
+ Please be aware that all the buffers need to be allocated as a physically
+ continuous array in which each element is a single buffer and has the size
+ of SMC_WR_BUF_SIZE (48) bytes. If the allocation fails, we keep retrying
+ with half of the buffer count until it is either successful or (unlikely)
+ we dip below the old hard coded value which is 48 where we give up much
+ like before having this control.
+
+ Default: 48
+
+limit_smc_hs - INTEGER
+ Whether to limit SMC handshake for newly created sockets.
+
+ When enabled, SMC listen path applies handshake limitation based on
+ handshake worker congestion and queued SMC handshake load.
+
+ Possible values:
+
+ - 0 - Disable handshake limitation
+ - 1 - Enable handshake limitation
+
+ Default: 0 (disable)
+
+hs_ctrl - STRING
+ Select the SMC handshake control profile by name.
+
+ This string refers to the name of a user-implemented
+ BPF struct_ops instance of type smc_hs_ctrl.
+
+ The selected profile controls whether SMC options are advertised
+ during TCP SYN/SYN-ACK handshake.
+
+ Only available when CONFIG_SMC_HS_CTRL_BPF is enabled.
+ Write an empty string to clear the current profile.
+
+ Default: empty string