On Sunday 10 October 2010 20:39:34 Arnd Bergmann wrote: > On Sunday 10 October 2010 19:33:52 Dan Carpenter wrote: > > We shouldn't return directly here because we're still holding the > > &soundcard_mutex. > > > > This bug goes all the way back to the start of git. It's strange that > > no one has complained about it as a runtime bug. > > > > CC: stable@xxxxxxxxxx > > Signed-off-by: Dan Carpenter <error27@xxxxxxxxx> > > It was only recently converted to a mutex from the BKL, which is much > more friendly to misusage because it is automatically released when > the kernel sleeps or when the program exits. > > The behavior was already broken with the BKL but the problem was far > less visible. I fear we might be seeing more of these as fallout from > the BKL removal. Sparse should be able to detect most of these cases > though, so maybe we can look more carefully for them. Hmm, actually sparse does *not* warn about sound_ioctl returning in different lock contexts. Sparse developers: is there a known limitation in sparse for this? I expected to see context warnings because sound_ioctl normally releases soundcard_mutex (previously lock_kernel) in some cases returns while holding the lock. Arnd -- To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
