Re: [RFC Patch v1 45/55] ARC: unaligned access emulation

From: Vineet Gupta
Date: Thu Dec 20 2012 - 05:30:26 EST

On Thursday 20 December 2012 12:29 PM, Vineet Gupta wrote:
> On Monday 12 November 2012 07:30 PM, Arnd Bergmann wrote:
>> On Monday 12 November 2012, Vineet.Gupta1@xxxxxxxxxxxx wrote:
>>> +
>>> + bool "Emulate unaligned memory access (userspace only)"
>>> + default N
>>> + help
>>> + This enables misaligned 16 & 32 bit memory access from user space.
>>> + Use ONLY-IF-ABS-NECESSARY as it will be very slow and also can hide
>>> + potential bugs in code
>> parisc and ia64 both have the same feature, and they use sysctl to configure
>> it at run-time. Maybe you should pick one of the two sysctl implementations
>> and hook that up to your implementation as well.
> Sounds like a good idea.
> Looking at your suggestion, the sysctl interface in both of those is for
> slightly different semantics and ARC would possibly need a bit from
> both. So to avoid duplication, I'm proposing following changes to
> kernel/sysctl.c and the generic options selected by respective arches.
> * no_unaligned_warning:CONFIG_IA64 => CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN
> *unaligned_enabled: __hppa__ => CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
> If you can think of better(smaller) names, please do let me know :-)
> If we agree in principle, I'll cookup the patches and seek the ACKs from
> ARCH maintainers (assuming my CC list above is right). And to keep
> things simple, we can route the kernel/sysctl.c changes via the ARC
> submission tree.
> Thx,
> Vineet

Sorry for a naive patch submitter question (yes I've already read
SubmittingPatches and googled much already). A lot of times, I see the
"Cc: ..." lines, just below the "Signed-off-by:" lines in the patch -
Are those added manually - because none of the xxx-cc options to
format-patch or send-email seem to be doing that - unless I missed some.

Context: I have the patch which touches ia64/parisc which I want to send
out and at the same time have those "Cc: lines for the maintainers too"


* It's OK to "look" fool once - rather than actually "being" a fool rest
of your life !
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