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

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <fed7ee473044432180c67b4adc0eb45d@AcuMS.aculab.com>
Date:   Sun, 23 Jan 2022 13:31:34 +0000
From:   David Laight <David.Laight@...LAB.COM>
To:     "'michael@...haelkloos.com'" <michael@...haelkloos.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.

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
Registration No: 1397386 (Wales)