From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from userp2130.oracle.com (userp2130.oracle.com [156.151.31.86]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3zWndl0KJszF0RY for ; Thu, 1 Feb 2018 02:45:46 +1100 (AEDT) Date: Wed, 31 Jan 2018 18:45:21 +0300 From: Dan Carpenter To: aneesh.kumar@linux.vnet.ibm.com Cc: linuxppc-dev@lists.ozlabs.org Subject: [bug report] powerpc/mm/radix: Add tlbflush routines Message-ID: <20180131154521.GA21698@mwanda> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Hello Aneesh Kumar K.V, The patch 1a472c9dba6b: "powerpc/mm/radix: Add tlbflush routines" from Apr 29, 2016, leads to the following static checker warning: arch/powerpc/mm/tlb_nohash.c:218 __local_flush_tlb_page() warn: always true condition '(pid != ~0) => (0-u32max != u64max)' arch/powerpc/mm/tlb_nohash.c 211 void __local_flush_tlb_page(struct mm_struct *mm, unsigned long vmaddr, 212 int tsize, int ind) 213 { 214 unsigned int pid; 215 216 preempt_disable(); 217 pid = mm ? mm->context.id : 0; 218 if (pid != MMU_NO_CONTEXT) ^^^^^^^^^^^^^^^^^^^^^ 219 _tlbil_va(vmaddr, pid, tsize, ind); 220 preempt_enable(); 221 } I don't know very much about PowerPC. The static checker is guessing which headers to pull in instead of relying on the build system so there are a lot of false positives. It's apparently using the arch/powerpc/include/asm/book3s/64/tlbflush.h header which does: #define MMU_NO_CONTEXT ~0UL so it's UINT_MAX vs U64_MAX which is making the checker complain. regards, dan carpenter