Oliver Hartkopp db9a140a85 can: isotp: set default value for N_As to 50 micro seconds ... [ Upstream commit 530e0d46c6 ] The N_As value describes the time a CAN frame needs on the wire when transmitted by the CAN controller. Even very short CAN FD frames need arround 100 usecs (bitrate 1Mbit/s, data bitrate 8Mbit/s). Having N_As to be zero (the former default) leads to 'no CAN frame separation' when STmin is set to zero by the receiving node. This 'burst mode' should not be enabled by default as it could potentially dump a high number of CAN frames into the netdev queue from the soft hrtimer context. This does not affect the system stability but is just not nice and cooperative. With this N_As/frame_txtime value the 'burst mode' is disabled by default. As user space applications usually do not set the frame_txtime element of struct can_isotp_options the new in-kernel default is very likely overwritten with zero when the sockopt() CAN_ISOTP_OPTS is invoked. To make sure that a N_As value of zero is only set intentional the value '0' is now interpreted as 'do not change the current value'. When a frame_txtime of zero is required for testing purposes this CAN_ISOTP_FRAME_TXTIME_ZERO u32 value has to be set in frame_txtime. Link: https://lore.kernel.org/all/20220309120416.83514-2-socketcan@hartkopp.net Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Sasha Levin <sashal@kernel.org>		2022-04-13 20:59:08 +02:00
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asm-generic	aio: fix use-after-free due to missing POLLFREE handling	2021-12-14 10:57:15 +01:00
drm	drm/tegra: Changes for v5.15-rc1	2021-08-26 13:05:19 +10:00
linux	can: isotp: set default value for N_As to 50 micro seconds	2022-04-13 20:59:08 +02:00
misc	habanalabs: fix resetting args in wait for CS IOCTL	2021-09-29 12:18:48 +03:00
mtd	mtd: add OTP (one-time-programmable) erase ioctl	2021-03-28 19:24:54 +02:00
rdma	Merge branch 'sg_nents' into rdma.git for-next	2021-08-30 09:49:59 -03:00
scsi	scsi: fc: Add EDC ELS definition	2021-08-24 22:56:33 -04:00
sound	ASoC: hdmi-codec: Fix OOB memory accesses	2022-02-08 18:34:03 +01:00
video
xen	xen/gntdev: gntdev.h: drop a duplicated word	2020-08-03 07:46:42 +02:00
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