Re: [PATCH] spi: Fix deadlock when adding SPI controllers on SPI buses

[Mark Brown <broonie@xxxxxxxxxx>]

On Wed, 13 Oct 2021 13:26:28 +0100, Mark Brown wrote:
> Currently we have a global spi_add_lock which we take when adding new
> devices so that we can check that we're not trying to reuse a chip
> select that's already controlled.  This means that if the SPI device is
> itself a SPI controller and triggers the instantiation of further SPI
> devices we trigger a deadlock as we try to register and instantiate
> those devices while in the process of doing so for the parent controller
> and hence already holding the global spi_add_lock.  Since we only care
> about concurrency within a single SPI bus move the lock to be per
> controller, avoiding the deadlock.
> 
> [...]

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git for-next

Thanks!

[1/1] spi: Fix deadlock when adding SPI controllers on SPI buses
      commit: 6098475d4cb48d821bdf453c61118c56e26294f0

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