Messages in this thread | | | Date | Tue, 20 Aug 2019 19:17:41 -0700 | From | Christoph Hellwig <> | Subject | Re: [PATCH 3/3] csky: Support kernel non-aligned access |
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On Tue, Aug 20, 2019 at 08:34:29PM +0800, guoren@kernel.org wrote: > From: Guo Ren <ren_guo@c-sky.com> > > We prohibit non-aligned access in kernel mode, but some special NIC > driver needs to support kernel-state unaligned access. For example, > when the bus does not support unaligned access, IP header parsing > will cause non-aligned access and driver does not recopy the skb > buffer to dma for performance reasons. > > Added kernel_enable & user_enable to control unaligned access and > added kernel_count & user_count for statistical unaligned access.
If the NIC drivers requires this it is buggy. Kernel code must use the get_unaligned* / put_unaligned* helpers for that.
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