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Date:   Mon, 10 Dec 2018 20:13:11 +0100
From:   Borislav Petkov <bp@alien8.de>
To:     Reinette Chatre <reinette.chatre@intel.com>
Cc:     tglx@linutronix.de, fenghua.yu@intel.com, tony.luck@intel.com,
        jithu.joseph@intel.com, mingo@redhat.com, hpa@zytor.com,
        x86@kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] x86/resctrl: Fix rdt_find_domain() return value checks
Message-ID: <20181210191311.GC5482@zn.tnic>
References: <d932648504b745cb51c4a440710c7a1ca9830eca.1543427858.git.reinette.chatre@intel.com>
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On Wed, Nov 28, 2018 at 10:20:27AM -0800, Reinette Chatre wrote:
> rdt_find_domain() may return an ERR_PTR(), NULL, or a pointer to struct
> rdt_domain. It is thus required that the return value be checked for the
> possibility of an ERR_PTR as well as NULL.

Well, it returns ERR_PTR(id) but code which uses ERR_PTR passes in an -E
value, for example ERR_PTR(-EINVAL) or so, and not an id.

And that might work now if id fits within that MAX_ERRNO range - I'm
looking at include/linux/err.h - but that's still fragile.

-- 
Regards/Gruss,
    Boris.

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