Messages in this thread | | | Date | Wed, 16 Nov 2022 14:59:15 +0100 | From | Uwe Kleine-König <> | Subject | Re: [PATCH 3/4] pwm: Mark free pwm IDs as used in alloc_pwms() |
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On Wed, Nov 16, 2022 at 10:17:08AM +0200, Andy Shevchenko wrote: > On Tue, Nov 15, 2022 at 10:15:14PM +0100, Uwe Kleine-König wrote: > > alloc_pwms() only identified a free range of IDs and this range was marked > > as used only later by pwmchip_add(). Instead let alloc_pwms() already do > > the marking (which makes the function actually allocating the range and so > > justifies the function name). This way access to the allocated_pwms > > bitfield is limited to two functions only. > > This change is a bit fragile in a long term. Currently we know that we have > no points of error after alloc_pwms() in ->probe(), but if somebody misses > this in the future, we became to the case where bitmap might be exhausted > (kinda resource leakage).
That is always the case for a function allocating resources. If you add an error path after the (previously) last allocation, you have to care for that.
Best regards Uwe
-- Pengutronix e.K. | Uwe Kleine-König | Industrial Linux Solutions | https://www.pengutronix.de/ | [unhandled content-type:application/pgp-signature] | |