twx-linux/include
David Lechner ca52aa4c60
spi: add defer_optimize_message controller flag
Adding spi_optimize_message() broke the spi-mux driver because it
calls spi_async() from it's transfer_one_message() callback. This
resulted in passing an incorrectly optimized message to the controller.
For example, if the underlying controller has an optimize_message()
callback, this would have not been called and can cause a crash when
the underlying controller driver tries to transfer the message.

Also, since the spi-mux driver swaps out the controller pointer by
replacing msg->spi, __spi_unoptimize_message() was being called with a
different controller than the one used in __spi_optimize_message(). This
could cause a crash when attempting to free the message resources when
__spi_unoptimize_message() is called in spi_finalize_current_message()
since it is being called with a controller that did not allocate the
resources.

This is fixed by adding a defer_optimize_message flag for controllers.
This flag causes all of the spi_[maybe_][un]optimize_message() calls to
be a no-op (other than attaching a pointer to the spi device to the
message).

This allows the spi-mux driver to pass an unmodified message to
spi_async() in spi_mux_transfer_one_message() after the spi device has
been swapped out. This causes __spi_optimize_message() and
__spi_unoptimize_message() to be called only once per message and with
the correct/same controller in each case.

Reported-by: Oleksij Rempel <o.rempel@pengutronix.de>
Closes: https://lore.kernel.org/linux-spi/Zn6HMrYG2b7epUxT@pengutronix.de/
Reported-by: Marc Kleine-Budde <mkl@pengutronix.de>
Closes: https://lore.kernel.org/linux-spi/20240628-awesome-discerning-bear-1621f9-mkl@pengutronix.de/
Fixes: 7b1d87af14d9 ("spi: add spi_optimize_message() APIs")
Signed-off-by: David Lechner <dlechner@baylibre.com>
Link: https://patch.msgid.link/20240708-spi-mux-fix-v1-2-6c8845193128@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2024-07-09 17:42:32 +01:00
..
acpi ACPI: EC: Evaluate orphan _REG under EC device 2024-06-13 11:28:54 +02:00
asm-generic asm-generic cleanups for 6.10 2024-05-20 15:18:34 -07:00
clocksource
crypto This push fixes a bug in the new ecc P521 code as well as a buggy 2024-05-20 08:47:54 -07:00
drm Short summary of fixes pull: 2024-05-27 13:47:14 +10:00
dt-bindings dt-bindings: net: dp8386x: Add MIT license along with GPL-2.0 2024-06-07 12:16:22 +01:00
keys
kunit
kvm
linux spi: add defer_optimize_message controller flag 2024-07-09 17:42:32 +01:00
math-emu
media
memory
misc
net netfilter: move the sysctl nf_hooks_lwtunnel into the netfilter core 2024-06-19 18:41:59 +02:00
pcmcia
ras tracing/treewide: Remove second parameter of __assign_str() 2024-05-22 20:14:47 -04:00
rdma The usual shower of singleton fixes and minor series all over MM, 2024-05-19 09:21:03 -07:00
rv
scsi scsi: core: Introduce the BLIST_SKIP_IO_HINTS flag 2024-06-13 21:03:13 -04:00
soc I'm actually surprised this time. There aren't any new Qualcomm SoC clk 2024-05-18 12:48:37 -07:00
sound ALSA: pcm: fix typo in comment 2024-05-29 10:40:36 +02:00
target
trace firewire fixes for v6.10-rc4 2024-06-16 09:58:02 -07:00
uapi vfs-6.10-rc4.fixes 2024-06-11 12:04:21 -07:00
ufs
vdso
video
xen