From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7F57EC433E0 for ; Sat, 27 Jun 2020 08:17:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 56B882080C for ; Sat, 27 Jun 2020 08:17:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593245851; bh=bx9KLSFLdGSv6yxlwrHpM9s3B00/UStRmHuswAZu/F8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=UNFNGbckxm+8E3GGIc25RpIyJ443g3046ZlthbhfOac30PTMvBQvMeyZsovPLlxIv BunAnlU1e1dpJlwkjjQhkdqLzp/xKQoPJbOt2Uez9C1YTcd9jGQiKn9WSqW596tt6w yUagco8awbl2HRaRMkyQbWrLo7lBjBB36OfQ3nAQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726448AbgF0IR3 (ORCPT ); Sat, 27 Jun 2020 04:17:29 -0400 Received: from mail.kernel.org ([198.145.29.99]:51608 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725900AbgF0IR2 (ORCPT ); Sat, 27 Jun 2020 04:17:28 -0400 Received: from aquarius.haifa.ibm.com (nesher1.haifa.il.ibm.com [195.110.40.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E78D22080C; Sat, 27 Jun 2020 08:17:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593245847; bh=bx9KLSFLdGSv6yxlwrHpM9s3B00/UStRmHuswAZu/F8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=HLsAxDlhu9peiDRGm42AmnHwmdxNLeX+5vyJdA9H00PPXL1Uz1guNAYGwdCjls/s1 t3fcBZhgP/JABf8HyibFlmJ5Qc//Q/ryvoSCK+Vf73G+tAjcRTYvv+eATJyO5lO88Q ZzwhqyhGSJNLrupWufetzZc+XXfsmDBLwPtHQLBY= From: Mike Rapoport To: sparclinux@vger.kernel.org Cc: David Miller , Linus Torvalds , Mike Rapoport , linux-kernel@vger.kernel.org, Mike Rapoport Subject: [PATCH v2 2/2] sparc32: srmmu: improve type safety of __nocache_fix() Date: Sat, 27 Jun 2020 11:16:53 +0300 Message-Id: <20200627081653.25311-3-rppt@kernel.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200627081653.25311-1-rppt@kernel.org> References: <20200627081653.25311-1-rppt@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Mike Rapoport The __nocache_fix(VADDR) macro is used to add an offset for pointers and its "return type" is 'void *'. We can do better and keep the type information with simply by casting the return value to (__typeof__(VADDR)). This will ".. show when those pgd/p4d/pud pointers get mis-used because they don't end up dropping the type info.." The addition of the casting to __nocache_fix() also allows to remove explicit casts at its call sites. Suggested-by: Linus Torvalds Signed-off-by: Mike Rapoport Link: https://lkml.kernel.org/r/CAHk-=wisORTa7QVPnFqNw9pFs62UiwgsD4C4d=MtYy1o4JPyGQ@mail.gmail.com --- arch/sparc/include/asm/pgtsrmmu.h | 2 +- arch/sparc/mm/srmmu.c | 16 ++++++++-------- 2 files changed, 9 insertions(+), 9 deletions(-) diff --git a/arch/sparc/include/asm/pgtsrmmu.h b/arch/sparc/include/asm/pgtsrmmu.h index 7708d015712b..6067925972d9 100644 --- a/arch/sparc/include/asm/pgtsrmmu.h +++ b/arch/sparc/include/asm/pgtsrmmu.h @@ -113,7 +113,7 @@ extern unsigned long last_valid_pfn; extern void *srmmu_nocache_pool; #define __nocache_pa(VADDR) (((unsigned long)VADDR) - SRMMU_NOCACHE_VADDR + __pa((unsigned long)srmmu_nocache_pool)) #define __nocache_va(PADDR) (__va((unsigned long)PADDR) - (unsigned long)srmmu_nocache_pool + SRMMU_NOCACHE_VADDR) -#define __nocache_fix(VADDR) __va(__nocache_pa(VADDR)) +#define __nocache_fix(VADDR) ((__typeof__(VADDR))__va(__nocache_pa(VADDR))) /* Accessing the MMU control register. */ unsigned int srmmu_get_mmureg(void); diff --git a/arch/sparc/mm/srmmu.c b/arch/sparc/mm/srmmu.c index f5fa07958f34..da4e10b4cb37 100644 --- a/arch/sparc/mm/srmmu.c +++ b/arch/sparc/mm/srmmu.c @@ -689,7 +689,7 @@ static void __init srmmu_early_allocate_ptable_skeleton(unsigned long start, pgdp = pgd_offset_k(start); p4dp = p4d_offset(pgdp, start); pudp = pud_offset(p4dp, start); - if (pud_none(*(pud_t *)__nocache_fix(pudp))) { + if (pud_none(*__nocache_fix(pudp))) { pmdp = __srmmu_get_nocache( SRMMU_PMD_TABLE_SIZE, SRMMU_PMD_TABLE_SIZE); if (pmdp == NULL) @@ -698,7 +698,7 @@ static void __init srmmu_early_allocate_ptable_skeleton(unsigned long start, pud_set(__nocache_fix(pudp), pmdp); } pmdp = pmd_offset(__nocache_fix(pudp), start); - if (srmmu_pmd_none(*(pmd_t *)__nocache_fix(pmdp))) { + if (srmmu_pmd_none(*__nocache_fix(pmdp))) { ptep = __srmmu_get_nocache(PTE_SIZE, PTE_SIZE); if (ptep == NULL) early_pgtable_allocfail("pte"); @@ -810,11 +810,11 @@ static void __init srmmu_inherit_prom_mappings(unsigned long start, p4dp = p4d_offset(pgdp, start); pudp = pud_offset(p4dp, start); if (what == 2) { - *(pgd_t *)__nocache_fix(pgdp) = __pgd(probed); + *__nocache_fix(pgdp) = __pgd(probed); start += PGDIR_SIZE; continue; } - if (pud_none(*(pud_t *)__nocache_fix(pudp))) { + if (pud_none(*__nocache_fix(pudp))) { pmdp = __srmmu_get_nocache(SRMMU_PMD_TABLE_SIZE, SRMMU_PMD_TABLE_SIZE); if (pmdp == NULL) @@ -828,7 +828,7 @@ static void __init srmmu_inherit_prom_mappings(unsigned long start, start += PMD_SIZE; continue; } - if (srmmu_pmd_none(*(pmd_t *)__nocache_fix(pmdp))) { + if (srmmu_pmd_none(*__nocache_fix(pmdp))) { ptep = __srmmu_get_nocache(PTE_SIZE, PTE_SIZE); if (ptep == NULL) early_pgtable_allocfail("pte"); @@ -836,7 +836,7 @@ static void __init srmmu_inherit_prom_mappings(unsigned long start, pmd_set(__nocache_fix(pmdp), ptep); } ptep = pte_offset_kernel(__nocache_fix(pmdp), start); - *(pte_t *)__nocache_fix(ptep) = __pte(probed); + *__nocache_fix(ptep) = __pte(probed); start += PAGE_SIZE; } } @@ -850,7 +850,7 @@ static void __init do_large_mapping(unsigned long vaddr, unsigned long phys_base unsigned long big_pte; big_pte = KERNEL_PTE(phys_base >> 4); - *(pgd_t *)__nocache_fix(pgdp) = __pgd(big_pte); + *__nocache_fix(pgdp) = __pgd(big_pte); } /* Map sp_bank entry SP_ENTRY, starting at virtual address VBASE. */ @@ -940,7 +940,7 @@ void __init srmmu_paging_init(void) srmmu_ctx_table_phys = (ctxd_t *)__nocache_pa(srmmu_context_table); for (i = 0; i < num_contexts; i++) - srmmu_ctxd_set((ctxd_t *)__nocache_fix(&srmmu_context_table[i]), srmmu_swapper_pg_dir); + srmmu_ctxd_set(__nocache_fix(&srmmu_context_table[i]), srmmu_swapper_pg_dir); flush_cache_all(); srmmu_set_ctable_ptr((unsigned long)srmmu_ctx_table_phys); -- 2.26.2