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Date:   Wed, 28 Jul 2021 10:36:03 -0500
From:   Bjorn Helgaas <helgaas@kernel.org>
To:     Krzysztof =?utf-8?Q?Wilczy=C5=84ski?= <kw@linux.com>
Cc:     Amey Narkhede <ameynarkhede03@gmail.com>,
        Bjorn Helgaas <bhelgaas@google.com>,
        alex.williamson@redhat.com,
        Raphael Norwitz <raphael.norwitz@nutanix.com>,
        linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org,
        Shanker Donthineni <sdonthineni@nvidia.com>,
        Sinan Kaya <okaya@kernel.org>, Len Brown <lenb@kernel.org>,
        "Rafael J . Wysocki" <rjw@rjwysocki.net>
Subject: Re: [PATCH v10 4/8] PCI/sysfs: Allow userspace to query and set
 device reset mechanism
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On Wed, Jul 28, 2021 at 03:27:40AM +0200, Krzysztof Wilczyński wrote:

> > > +	options = kstrndup(buf, count, GFP_KERNEL);
> > 
> > I assume the kstrndup() is because strsep() writes into the buffer?
> 
> Yes, Amey added kstrndup() in v6 following my recommendation as per:
> 
>   https://lore.kernel.org/linux-pci/20210606125800.GA76573@rocinante.localdomain/
> 
> This was to avoid removing the const quantifier through a type cast
> given that the signature of the function denotes that the buffer is
> a pointer to immutable string, as per:
> 
>   https://elixir.bootlin.com/linux/v5.14-rc3/source/include/linux/device/driver.h#L137

Ah, right, thanks!  Definitely prefer not to cast away the constness.

I guess the strings here are short (<100 chars max), so no big deal to
duplicate them.  Sorry for the noise!