Feature #3224
Updated by Denis Efremov over 12 years ago
commit 1c6c69525b40eb76de8adf039409722015927dc3
https://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=commit;h=1c6c6952
Requesting a threaded interrupt without a primary handler and without
IRQF_ONESHOT set is dangerous.
The core will use the default primary handler for it, which merily
wakes the thread. For a level type interrupt this results in an
interrupt storm, because the interrupt line is reenabled after the
primary handler runs. The device has still the line asserted, which
brings us back into the primary handler.
While this works for edge type interrupts, we play it safe and reject
unconditionally because we can't say for sure which type this
interrupt really has. The type flags are unreliable as the underlying
chip implementation can override them. And we cannot assume that
developers using that interface know what they are doing.
Fixing commits:
1) https://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=commitdiff;h=623b51fc8642fd3c795fa9903be3adaa537ad9c5
2) https://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=commitdiff;h=a76beb14123a69ca080f5a5425e28b786d62318d
3) https://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=commitdiff;h=6b91bf1a3f52f5fdf40f5aaeb09a06b4d49556cc
4) https://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=commitdiff;h=16a50b1270455a6d41f9f6d8f99a72cf9d76824a