| Message ID | cover.1701274975.git.namcao@linutronix.de |
|---|---|
| Headers | show |
| Series | spi: spl022: fix sleeping in interrupt context | expand |
On Wed, 29 Nov 2023 17:31:54 +0100, Nam Cao wrote: > While running the spl022, I got the following warning: > BUG: sleeping function called from invalid context at drivers/spi/spi.c:1428 > > This is because between spi transfers, spi_transfer_delay_exec() (who > may sleep if the delay is >10us) is called in interrupt context. This is > a problem for anyone who runs this driver and need more than 10us delay. > > [...] Applied to https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git for-next Thanks! [1/2] spi: introduce SPI_TRANS_FAIL_IO for error reporting commit: 39cefd85098d12439586824c39f8e1948fac186d [2/2] spi: spl022: switch to use default spi_transfer_one_message() commit: 9b2ef250b31d46f7ef522bd1bd84942f998bb3f9 All being well this means that it will be integrated into the linux-next tree (usually sometime in the next 24 hours) and sent to Linus during the next merge window (or sooner if it is a bug fix), however if problems are discovered then the patch may be dropped or reverted. You may get further e-mails resulting from automated or manual testing and review of the tree, please engage with people reporting problems and send followup patches addressing any issues that are reported if needed. If any updates are required or you are submitting further changes they should be sent as incremental updates against current git, existing patches will not be replaced. Please add any relevant lists and maintainers to the CCs when replying to this mail. Thanks, Mark
Hi, While running the spl022, I got the following warning: BUG: sleeping function called from invalid context at drivers/spi/spi.c:1428 This is because between spi transfers, spi_transfer_delay_exec() (who may sleep if the delay is >10us) is called in interrupt context. This is a problem for anyone who runs this driver and need more than 10us delay. Patch 1 adds an error reporting mechanism, needed by patch 2 who switch to use the default spi_transfer_one_message(), which fix the problem. The series is tested with polling transfer mode and interrupt transfer mode. I can't test the DMA mode, so some help testing here is very appreciated. One question: This series is quite big for stable trees, so how can we backport this fix? We can: - Let it be released, and get tested for some time. After a while without any reported problem, backport it. - Have a small patch which fixes this problem. One idea I have is to switch the current interrupt handler to threaded interrupt handler, and switch from existing use of tasklet to workqueue. So that the driver can safely sleep if needed. And then add this series on top of that. - other options that I miss? Best regards, Nam v2: add some documents for the new flag. No functional change. Nam Cao (2): spi: introduce SPI_TRANS_FAIL_IO for error reporting spi: spl022: switch to use default spi_transfer_one_message() drivers/spi/spi-pl022.c | 372 +++++++--------------------------------- drivers/spi/spi.c | 3 + include/linux/spi/spi.h | 12 +- 3 files changed, 77 insertions(+), 310 deletions(-)