From patchwork Thu Aug 12 23:37:36 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vineet Gupta X-Patchwork-Id: 1516469 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (no SPF record) smtp.mailfrom=lists.infradead.org (client-ip=2607:7c80:54:e::133; helo=bombadil.infradead.org; envelope-from=linux-snps-arc-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org; receiver=) Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; secure) header.d=lists.infradead.org header.i=@lists.infradead.org header.a=rsa-sha256 header.s=bombadil.20210309 header.b=ZHBdGkMj; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=ZGpgx3NY; dkim-atps=neutral Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4Gm35q6Cp1z9t8j for ; Fri, 13 Aug 2021 09:38:07 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=Hj+EcBbiWJicudlmjGUaU0kR8T41OZJ41C0xIzpew6g=; b=ZHBdGkMjlgf2b7 JrKHGVg/vO92sPehr14h6ZHoHnLeP2sDlF9v/KCNWmqMeUjPYvbiEOF5BLb/Y2QmMTTDKgAhAbVBi FT7jXdLD/YX+lgg2JpJrXD8HzXBZ0CHR+df9dl6keaK0rRROsMuLkdDVNv2FFV4uGM8J0nj3Xj0Ae dJNSA0P910cMOzDbR1r3K+WEuIH5vj6eYl38viSIjWvu95J+bAlg/O0bT5vz0vl0hteKhQOYuVaIk A7W3dvXRz2oDrLhG5Lcmnn6C+sYDUtnwOncg/1k/YVgVmG2dsiHBLJRAbWJ/DhoUvrb5dIh5YCxnY JpFtPeJBiMtJdOOpmswg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mEKGy-00BTxJ-M9; Thu, 12 Aug 2021 23:38:04 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1mEKGs-00BTrk-IE for linux-snps-arc@lists.infradead.org; Thu, 12 Aug 2021 23:38:02 +0000 Received: by mail.kernel.org (Postfix) with ESMTPSA id 02C38610A4; Thu, 12 Aug 2021 23:37:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1628811478; bh=yKgAZpCv9bEnKnaHu5fqX12u7Ay6u1osj+T/lRSld68=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZGpgx3NY0Whw2BFWOk6BtzWzxx0jTpr4YQiu0JigeB8zNzkn4UxnpPpWXDeeOJt7R c/3LJUbGlThxuLdu8JFlWtustZcS9YG49Nqi+kpM7Uz3zyQfxcg21caTlQa9beQTX1 oUjgy8PZQ3T3pOsyHusjhDr1BZIH5iw0BthWH/Uv1y961iQj0Vn8qNhNq2xMnQ+9Vm 75p455RzRdsBWBeiFAY/XBpGxnZ1YK/rWJ6gnkd5/LJszkzAqiSZe2djDLSUyXgr+y 56sdKqbtiBoSYPSjk07qo2bbwdhv9jbh6XXG1KpcMns5IjNoHNerHvNJa4KY2yY31F iUU6H2VWWk5KA== From: Vineet Gupta To: linux-snps-arc@lists.infradead.org Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Anshuman Khandual , Mike Rapoport , Vineet Gupta Subject: [PATCH v2 02/19] ARC: mm: remove tlb paranoid code Date: Thu, 12 Aug 2021 16:37:36 -0700 Message-Id: <20210812233753.104217-3-vgupta@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210812233753.104217-1-vgupta@kernel.org> References: <20210812233753.104217-1-vgupta@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210812_163758_676252_26C2C812 X-CRM114-Status: GOOD ( 15.59 ) X-Spam-Score: -5.4 (-----) X-Spam-Report: Spam detection software, running on the system "bombadil.infradead.org", has NOT identified this incoming email as spam. The original message has been attached to this so you can view it or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: This was used back in arc700 days when ASID allocator was fragile. Not needed in last 5 years Signed-off-by: Vineet Gupta --- arch/arc/Kconfig | 3 --- arch/arc/include/asm/mmu.h | 6 ----- arch/arc/mm/tlb.c | 40 arch/arc/mm/tlbex.S | 50 ------- [...] Content analysis details: (-5.4 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -5.0 RCVD_IN_DNSWL_HI RBL: Sender listed at https://www.dnswl.org/, high trust [198.145.29.99 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID_EF Message has a valid DKIM or DK signature from envelope-from domain -0.2 DKIMWL_WL_HIGH DKIMwl.org - High trust sender X-BeenThere: linux-snps-arc@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Linux on Synopsys ARC Processors List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-snps-arc" Errors-To: linux-snps-arc-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org This was used back in arc700 days when ASID allocator was fragile. Not needed in last 5 years Signed-off-by: Vineet Gupta --- arch/arc/Kconfig | 3 --- arch/arc/include/asm/mmu.h | 6 ----- arch/arc/mm/tlb.c | 40 ------------------------------ arch/arc/mm/tlbex.S | 50 -------------------------------------- 4 files changed, 99 deletions(-) diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig index 0680b1de0fc3..59d5b2a179f6 100644 --- a/arch/arc/Kconfig +++ b/arch/arc/Kconfig @@ -537,9 +537,6 @@ config ARC_DW2_UNWIND If you don't debug the kernel, you can say N, but we may not be able to solve problems without frame unwind information -config ARC_DBG_TLB_PARANOIA - bool "Paranoia Checks in Low Level TLB Handlers" - config ARC_DBG_JUMP_LABEL bool "Paranoid checks in Static Keys (jump labels) code" depends on JUMP_LABEL diff --git a/arch/arc/include/asm/mmu.h b/arch/arc/include/asm/mmu.h index 4065335a7922..38a036508699 100644 --- a/arch/arc/include/asm/mmu.h +++ b/arch/arc/include/asm/mmu.h @@ -64,12 +64,6 @@ typedef struct { unsigned long asid[NR_CPUS]; /* 8 bit MMU PID + Generation cycle */ } mm_context_t; -#ifdef CONFIG_ARC_DBG_TLB_PARANOIA -void tlb_paranoid_check(unsigned int mm_asid, unsigned long address); -#else -#define tlb_paranoid_check(a, b) -#endif - void arc_mmu_init(void); extern char *arc_mmu_mumbojumbo(int cpu_id, char *buf, int len); void read_decode_mmu_bcr(void); diff --git a/arch/arc/mm/tlb.c b/arch/arc/mm/tlb.c index 349fb7a75d1d..6079dfd129b9 100644 --- a/arch/arc/mm/tlb.c +++ b/arch/arc/mm/tlb.c @@ -400,7 +400,6 @@ void create_tlb(struct vm_area_struct *vma, unsigned long vaddr, pte_t *ptep) * * Removing the assumption involves * -Using vma->mm->context{ASID,SASID}, as opposed to MMU reg. - * -Fix the TLB paranoid debug code to not trigger false negatives. * -More importantly it makes this handler inconsistent with fast-path * TLB Refill handler which always deals with "current" * @@ -423,8 +422,6 @@ void create_tlb(struct vm_area_struct *vma, unsigned long vaddr, pte_t *ptep) local_irq_save(flags); - tlb_paranoid_check(asid_mm(vma->vm_mm, smp_processor_id()), vaddr); - vaddr &= PAGE_MASK; /* update this PTE credentials */ @@ -818,40 +815,3 @@ void do_tlb_overlap_fault(unsigned long cause, unsigned long address, local_irq_restore(flags); } - -/*********************************************************************** - * Diagnostic Routines - * -Called from Low Level TLB Handlers if things don;t look good - **********************************************************************/ - -#ifdef CONFIG_ARC_DBG_TLB_PARANOIA - -/* - * Low Level ASM TLB handler calls this if it finds that HW and SW ASIDS - * don't match - */ -void print_asid_mismatch(int mm_asid, int mmu_asid, int is_fast_path) -{ - pr_emerg("ASID Mismatch in %s Path Handler: sw-pid=0x%x hw-pid=0x%x\n", - is_fast_path ? "Fast" : "Slow", mm_asid, mmu_asid); - - __asm__ __volatile__("flag 1"); -} - -void tlb_paranoid_check(unsigned int mm_asid, unsigned long addr) -{ - unsigned int mmu_asid; - - mmu_asid = read_aux_reg(ARC_REG_PID) & 0xff; - - /* - * At the time of a TLB miss/installation - * - HW version needs to match SW version - * - SW needs to have a valid ASID - */ - if (addr < 0x70000000 && - ((mm_asid == MM_CTXT_NO_ASID) || - (mmu_asid != (mm_asid & MM_CTXT_ASID_MASK)))) - print_asid_mismatch(mm_asid, mmu_asid, 0); -} -#endif diff --git a/arch/arc/mm/tlbex.S b/arch/arc/mm/tlbex.S index bcd2909c691f..0b4bb62fa0ab 100644 --- a/arch/arc/mm/tlbex.S +++ b/arch/arc/mm/tlbex.S @@ -93,11 +93,6 @@ ex_saved_reg1: st_s r1, [r0, 4] st_s r2, [r0, 8] st_s r3, [r0, 12] - - ; VERIFY if the ASID in MMU-PID Reg is same as - ; one in Linux data structures - - tlb_paranoid_check_asm .endm .macro TLBMISS_RESTORE_REGS @@ -146,51 +141,6 @@ ex_saved_reg1: #endif -;============================================================================ -; Troubleshooting Stuff -;============================================================================ - -; Linux keeps ASID (Address Space ID) in task->active_mm->context.asid -; When Creating TLB Entries, instead of doing 3 dependent loads from memory, -; we use the MMU PID Reg to get current ASID. -; In bizzare scenrios SW and HW ASID can get out-of-sync which is trouble. -; So we try to detect this in TLB Mis shandler - -.macro tlb_paranoid_check_asm - -#ifdef CONFIG_ARC_DBG_TLB_PARANOIA - - GET_CURR_TASK_ON_CPU r3 - ld r0, [r3, TASK_ACT_MM] - ld r0, [r0, MM_CTXT+MM_CTXT_ASID] - breq r0, 0, 55f ; Error if no ASID allocated - - lr r1, [ARC_REG_PID] - and r1, r1, 0xFF - - and r2, r0, 0xFF ; MMU PID bits only for comparison - breq r1, r2, 5f - -55: - ; Error if H/w and S/w ASID don't match, but NOT if in kernel mode - lr r2, [erstatus] - bbit0 r2, STATUS_U_BIT, 5f - - ; We sure are in troubled waters, Flag the error, but to do so - ; need to switch to kernel mode stack to call error routine - GET_TSK_STACK_BASE r3, sp - - ; Call printk to shoutout aloud - mov r2, 1 - j print_asid_mismatch - -5: ; ASIDs match so proceed normally - nop - -#endif - -.endm - ;============================================================================ ;TLB Miss handling Code ;============================================================================