f7b9e814ab
[ Upstream commit e43111f52b9ec5c2d700f89a1d61c8d10dc2d9e9 ] Dan pointed out that Smatch is concerned about this code because it uses spin_lock_irqsave() and then calls wait_event_lock_irq() which enables irqs before going to sleep. The comment above the function says it should be called with interrupts enabled, but we simply hope that's true without really confirming that. Let's add a might_sleep() here to confirm that interrupts and preemption aren't disabled. Once we do that, we can change the lock to be non-saving, spin_lock_irq(), to clarify that we don't expect irqs to be disabled. If irqs are disabled by callers they're going to be enabled anyway in the wait_event_lock_irq() call which would be bad. This should make Smatch happier and find bad callers faster with the might_sleep(). We can drop the WARN_ON() in the caller because we have the might_sleep() now, simplifying the code. Reported-by: Dan Carpenter <dan.carpenter@linaro.org> Closes: https://lore.kernel.org/r/911181ed-c430-4592-ad26-4dc948834e08@moroto.mountain Fixes: 2bc20f3c8487 ("soc: qcom: rpmh-rsc: Sleep waiting for tcs slots to be free") Cc: Douglas Anderson <dianders@chromium.org> Signed-off-by: Stephen Boyd <swboyd@chromium.org> Reviewed-by: Douglas Anderson <dianders@chromium.org> Link: https://lore.kernel.org/r/20240509184129.3924422-1-swboyd@chromium.org Signed-off-by: Bjorn Andersson <andersson@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.