On 3/26/2019 2:09 PM, Yuri Norov wrote:
+ Mike Travis <tra...@sgi.com>
+ Thomas Gleixner <t...@linutronix.de>
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On Tue, Mar 26, 2019 at 12:07:45AM +0300, Yury Norov wrote:
The requirement for this rework is to keep the __bitmap_parselist()
copy-less and single-pass but make it more readable and maintainable by
splitting into logical parts and removing explicit nested cycles and
opaque local variables.
__bitmap_parselist() can parse userspace inputs and therefore we cannot
use simple_strtoul() to parse numbers.
So, all above depends to what memory we access kernel / user space.
Perhaps we can get copy of memory of a given size and then parse it in kernel
space always?
--
With Best Regards,
Andy Shevchenko
What I missed during rework is that we have only one caller of *parselist_userĀ
-
it's write_irq_affinity() introduced by Mike Travis in kernel/irq/proc.c. It
doesn't look
like a hot path as it's file operations handler. If no objections from Mike or
Thomas,
No objections from me as long as you can still change irq affinity using
a cpulist instead of a cpumask.
Thanks,
Mike Travis
I think it would make sense to copy_from_user() the userspace data at the
beginning
in sake of simplicity of __bitmap_parselist(), as you suggested above.
Yury