kernel/arch/um/drivers/chan_user.c, branch linux-rolling-stable

um: Use os_set_pdeathsig helper in winch thread/process

2024-10-25T09:34:55Z

Since we have a helper now, let's switch to using it. It will make the code slightly more consistent. Signed-off-by: Tiwei Bie Link: https://patch.msgid.link/20241024142828.2612828-5-tiwei.btw@antgroup.com Signed-off-by: Johannes Berg

um: Set parent death signal for winch thread/process

2024-10-10T11:37:21Z

The winch "thread" is really a separate process. Using prctl to set PR_SET_PDEATHSIG ensures that this separate thread will be killed if the UML kernel itself dies unexpectedly and does not perform proper cleanup. Signed-off-by: Benjamin Berg Link: https://patch.msgid.link/20240919124511.282088-5-benjamin@sipsolutions.net Signed-off-by: Johannes Berg

um: chan_user: retry partial writes

2024-07-03T10:18:02Z

In the next commit, we are going to set the output FD to be blocking. Once that is done, the write() may be short if an interrupt happens while it is writing out data. As such, to properly catch an EINTR error, we need to retry the write. Signed-off-by: Benjamin Berg Link: https://patch.msgid.link/20231018123643.1255813-3-benjamin@sipsolutions.net Signed-off-by: Johannes Berg

um: chan_user: catch EINTR when reading and writing

2024-07-03T10:18:01Z

If the read/write function returns an error then we expect to see an event/IRQ later on. However, this will only happen after an EAGAIN as we are using edge based event triggering. As such, EINTR needs to be caught should it happen. Signed-off-by: Benjamin Berg Link: https://patch.msgid.link/20231018123643.1255813-2-benjamin@sipsolutions.net Signed-off-by: Johannes Berg

Merge tag 'tty-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

2024-01-18T19:37:24Z

Pull tty / serial updates from Greg KH: "Here is the big set of tty and serial driver changes for 6.8-rc1. As usual, Jiri has a bunch of refactoring and cleanups for the tty core and drivers in here, along with the usual set of rs485 updates (someday this might work properly...) Along with those, in here are changes for: - sc16is7xx serial driver updates - platform driver removal api updates - amba-pl011 driver updates - tty driver binding updates - other small tty/serial driver updates and changes All of these have been in linux-next for a while with no reported issues" * tag 'tty-6.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (197 commits) serial: sc16is7xx: refactor EFR lock serial: sc16is7xx: reorder code to remove prototype declarations serial: sc16is7xx: refactor FIFO access functions to increase commonality serial: sc16is7xx: drop unneeded MODULE_ALIAS serial: sc16is7xx: replace hardcoded divisor value with BIT() macro serial: sc16is7xx: add explicit return for some switch default cases serial: sc16is7xx: add macro for max number of UART ports serial: sc16is7xx: add driver name to struct uart_driver serial: sc16is7xx: use i2c_get_match_data() serial: sc16is7xx: use spi_get_device_match_data() serial: sc16is7xx: use DECLARE_BITMAP for sc16is7xx_lines bitfield serial: sc16is7xx: improve do/while loop in sc16is7xx_irq() serial: sc16is7xx: remove obsolete loop in sc16is7xx_port_irq() serial: sc16is7xx: set safe default SPI clock frequency serial: sc16is7xx: add check for unsupported SPI modes during probe serial: sc16is7xx: fix invalid sc16is7xx_lines bitfield in case of probe error serial: 8250_exar: Set missing rs485_supported flag serial: omap: do not override settings for RS485 support serial: core, imx: do not set RS485 enabled if it is not supported serial: core: make sure RS485 cannot be enabled when it is not supported ...

um: Reap winch thread if it fails

2024-01-04T22:51:23Z

When the winch thread runs into an error condition, it would exit(1) and never be reaped until shutdown time. Change this to write a command byte which causes the driver to kill it, therefore reaping the child. Signed-off-by: Benjamin Berg Signed-off-by: Richard Weinberger

um: Do not use printk in SIGWINCH helper thread

2024-01-04T22:51:00Z

The thread is running outside of the UML kernel scope and is a helper. As such, printk cannot work and os_info must be used instead. Signed-off-by: Benjamin Berg Signed-off-by: Richard Weinberger

tty: um: convert to u8/__u8 and size_t

2023-12-08T11:02:38Z

Switch character types to u8 and sizes to size_t. To conform to characters/sizes in the rest of the tty layer. Note we use __u8 in the userspace files. Signed-off-by: "Jiri Slaby (SUSE)" Cc: Richard Weinberger Cc: Anton Ivanov Cc: Johannes Berg Cc: linux-um@lists.infradead.org Link: https://lore.kernel.org/r/20231206073712.17776-27-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman

um: chan_user: Fix winch_tramp() return value

2022-05-27T07:03:41Z

The previous fix here was only partially correct, it did result in returning a proper error value in case of error, but it also clobbered the pid that we need to return from this function (not just zero for success). As a result, it returned 0 here, but later this is treated as a pid and used to kill the process, but since it's now 0 we kill(0, SIGKILL), which makes UML kill itself rather than just the helper thread. Fix that and make it more obvious by using a separate variable for the pid. Fixes: ccf1236ecac4 ("um: fix error return code in winch_tramp()") Reported-and-tested-by: Nathan Chancellor Signed-off-by: Johannes Berg Cc: stable@vger.kernel.org Signed-off-by: Richard Weinberger

um: fix error return code in winch_tramp()

2021-06-17T20:10:56Z

Fix to return a negative error code from the error handling case instead of 0, as done elsewhere in this function. Fixes: 89df6bfc0405 ("uml: DEBUG_SHIRQ fixes") Reported-by: Hulk Robot Signed-off-by: Zhen Lei Acked-By: anton.ivanov@cambridgegreys.com Signed-off-by: Richard Weinberger