linux-kernel - Re: [PATCH v2] Fixed: Misaligned memory access. Fixed pointer comparison.

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Message-ID: <c184c65e-c960-8ecc-7cfe-d58af1cde0a3@michaelkloos.com>
Date:   Sun, 23 Jan 2022 11:53:31 -0500
From:   "Michael T. Kloos" <michael@...haelkloos.com>
To:     David Laight <David.Laight@...LAB.COM>,
        "paul.walmsley@...ive.com" <paul.walmsley@...ive.com>,
        "palmer@...belt.com" <palmer@...belt.com>,
        "aou@...s.berkeley.edu" <aou@...s.berkeley.edu>
Cc:     "linux-riscv@...ts.infradead.org" <linux-riscv@...ts.infradead.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v2] Fixed: Misaligned memory access. Fixed pointer
 comparison.

No.  It only uses tabs.  The previous version used spaces.
Make sure that you are not looking at a line with a '-'.
The only place that spaces, perhaps combined with tabs, appear
at the start of a line in my patch is to align the '*' character
for a multi-line comment.  In this case, tab(s) are followed by
a single space for alignment.  I believe this is correct per
the coding style.  If I am wrong, please let me know.

	----Michael

On 1/23/22 08:31, David Laight wrote:

> From: michael@...haelkloos.com
>> 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
>
> -
> Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
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