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Date:   Thu, 15 Apr 2021 08:53:35 +0100
From:   Christoph Hellwig <hch@infradead.org>
To:     Nathan Chancellor <nathan@kernel.org>
Cc:     Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Sami Tolvanen <samitolvanen@google.com>,
        Kees Cook <keescook@chromium.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Jiri Olsa <jolsa@redhat.com>,
        Namhyung Kim <namhyung@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Borislav Petkov <bp@alien8.de>, x86@kernel.org,
        linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com
Subject: Re: [PATCH 1/2] x86/events/amd/iommu: Fix sysfs type mismatch
Message-ID: <20210415075335.GA1954964@infradead.org>
References: <20210415001112.3024673-1-nathan@kernel.org>
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On Wed, Apr 14, 2021 at 05:11:11PM -0700, Nathan Chancellor wrote:
> dev_attr_show() calls _iommu_event_show() via an indirect call but
> _iommu_event_show()'s type does not currently match the type of the
> show() member in 'struct device_attribute', resulting in a Control Flow
> Integrity violation.

While the fix looks fine I think we need to solve this kind of problem
by better type checking.  The fact that we can use the wong type here
without a compiler warning is the real issue.