Messages in this thread | | | From | Krzysztof Hałasa <> | Subject | Re: Data corruption on i.MX6 IPU in arm_copy_from_user() | Date | Wed, 26 May 2021 14:29:07 +0200 |
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"Russell King (Oracle)" <linux@armlinux.org.uk> writes:
> Surely someone is not using copy_*_user() to copy data from userspace > direct to MMIO space... that would be crazy.
No, it's the other way around: reading MMIO mapped to userspace (mmap on /dev/mem) and copying it to simple kernel buffer (e.g. pipe buffer). I.e., the MMIO is the userspace here (thus copy_from_user()). -- Krzysztof Hałasa
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