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Message-ID: <20250806020744.yj2f7z6ntdqnv2ff@master> Reply-To: Wei Yang References: <20250805175140.241656-1-ziy@nvidia.com> Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250805175140.241656-1-ziy@nvidia.com> User-Agent: NeoMutt/20170113 (1.7.2) On Tue, Aug 05, 2025 at 01:51:40PM -0400, Zi Yan wrote: >FORCE_READ() converts input value x to its pointer type then reads from >address x. This is wrong. If x is a non-pointer, it would be caught it >easily. But all FORCE_READ() callers are trying to read from a pointer and >FORCE_READ() basically reads a pointer to a pointer instead of the original >typed pointer. Almost no access violation was found, except the one from >split_huge_page_test. > >Fix it by implementing a simplified READ_ONCE() instead. > >Fixes: 3f6bfd4789a0 ("selftests/mm: reuse FORCE_READ to replace "asm volatile("" : "+r" (XXX));"") >Signed-off-by: Zi Yan >--- Reviewed-by: Wei Yang -- Wei Yang Help you, Help me