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From:   Roman Kiryanov <rkir@google.com>
Date:   Tue, 16 Oct 2018 13:48:16 -0700
Message-ID: <CAOGAQepYWjm1TzLaRXnhFksDuQR-ukeChfHFRj1=uWyaUe-i+w@mail.gmail.com>
Subject: Re: [PATCH v3 06/15] platform: goldfish: pipe: Move memory allocation
 from probe to init
To:     gregkh@linuxfoundation.org
Cc:     linux-kernel@vger.kernel.org, Todd Kjos <tkjos@google.com>
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> I think we are getting our terms confused here.
>
> "init" usually means module_init(), is that what you are referring to
> here?

This is just a function that probe calls to, goldfish_pipe_device_v2_init.

https://android.googlesource.com/kernel/goldfish/+/android-goldfish-4.14-dev/drivers/platform/goldfish/goldfish_pipe_v2.c#1128

> Why would your probe function know, or care, about versions?

Different driver versions allocate different state.

> How is your probe function learning about the "version" to use here?

writel(PIPE_DRIVER_VERSION, base + PIPE_V2_REG_VERSION);
version = readl(base + PIPE_V2_REG_VERSION);

https://android.googlesource.com/kernel/goldfish/+/android-goldfish-4.14-dev/drivers/platform/goldfish/goldfish_pipe.c#106

> You have to clean up after your probe function failing before you return
> from it.

Are you saying that devm_kzalloc does not free memory if probe fails?
Is this useful?
I can free memory myself then.