RE: [PATCH v2] Fixed: Misaligned memory access. Fixed pointer comparison.

From: David Laight
Date: Sun Jan 23 2022 - 08:31:56 EST


From: michael@xxxxxxxxxxxxxxxx
> Sent: 23 January 2022 03:45
>
> Rewrote the riscv memmove() assembly implementation. The
> previous implementation did not check memory alignment and it
> compared 2 pointers with a signed comparison. The misaligned
> memory access would cause the kernel to crash on systems that
> did not emulate it in firmware and did not support it in hardware.
> Firmware emulation is slow and may not exist. Additionally,
> hardware support may not exist and would likely still run slower
> than aligned accesses even if it did. The RISC-V spec does not
> guarantee that support for misaligned memory accesses will exist.
> It should not be depended on.
...

>From the way my email client display the patch I think it is
using both tabs and spaces for indentation.

David

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