> Hum, I'm surprised that SELinux blocks such safe function. Maybe the SELinux policy should be completed to allow it?
The ioctl is blocked for given file type regardless of request argument. As I'm running Python on non-rooted Android updating policy is not really an option.

> But do you expect ioctl() to always fail with EACCESS? Or only fail sometimes, or only on some file descriptors? Your patch remembers that ioctl() fails once and never retries.
It will always fail for given file type (such as sockets), while it will work for others (such as regular files). I think that remembering that ioctl doesn't work may be okay, though I may be wrong. Either way if we are wrong whenever ioctl works we'll do one extra syscall.

> About your patch: please add a comment explaining why you fallback with a reference to this issue ("Issue #27057").
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