From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (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 3y1Yfn6sZVzDsPC for ; Tue, 26 Sep 2017 18:15:29 +1000 (AEST) Received: from pps.filterd (m0098404.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id v8Q8EhuO060240 for ; Tue, 26 Sep 2017 04:15:27 -0400 Received: from e06smtp10.uk.ibm.com (e06smtp10.uk.ibm.com [195.75.94.106]) by mx0a-001b2d01.pphosted.com with ESMTP id 2d7hxm592y-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Tue, 26 Sep 2017 04:15:26 -0400 Received: from localhost by e06smtp10.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 26 Sep 2017 09:15:24 +0100 From: Christophe Lombard To: linuxppc-dev@lists.ozlabs.org, fbarrat@linux.vnet.ibm.com, vaibhav@linux.vnet.ibm.com, andrew.donnellan@au1.ibm.com Subject: [PATCH V3] cxl: Fix memory page not handled Date: Tue, 26 Sep 2017 10:15:21 +0200 Message-Id: <1506413721-25306-1-git-send-email-clombard@linux.vnet.ibm.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , The in-kernel 'library' API can be called by drivers to help interaction with an IBM XSL on a POWER9 system. The cxllib_handle_fault() API is used to handle memory fault. All memory pages of the specified buffer have to be handled but under certain conditions,the last page may not be touched, and the address the adapter is trying to access is never sent to the kernel for resolution. This patch reworks start address of the loop with an address aligned on the page size. In this context, the last page is not missed. Signed-off-by: Christophe Lombard Acked-by: Frederic Barrat Acked-by: Andrew Donnellan Fixes: 3ced8d730063 ("cxl: Export library to support IBM XSL"); --- Changelog[v3] - Rebase to latest upstream. - Change end address condition Changelog[v2] - Rebase to latest upstream. - Change the start address of the loop. - Rewrite the commit message. --- drivers/misc/cxl/cxllib.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/drivers/misc/cxl/cxllib.c b/drivers/misc/cxl/cxllib.c index 5dba23c..dc9bc18 100644 --- a/drivers/misc/cxl/cxllib.c +++ b/drivers/misc/cxl/cxllib.c @@ -219,8 +219,17 @@ int cxllib_handle_fault(struct mm_struct *mm, u64 addr, u64 size, u64 flags) down_read(&mm->mmap_sem); - for (dar = addr; dar < addr + size; dar += page_size) { - if (!vma || dar < vma->vm_start || dar > vma->vm_end) { + vma = find_vma(mm, addr); + if (!vma) { + pr_err("Can't find vma for addr %016llx\n", addr); + rc = -EFAULT; + goto out; + } + /* get the size of the pages allocated */ + page_size = vma_kernel_pagesize(vma); + + for (dar = (addr & ~(page_size - 1)); dar < (addr + size); dar += page_size) { + if (dar < vma->vm_start || dar >= vma->vm_end) { vma = find_vma(mm, addr); if (!vma) { pr_err("Can't find vma for addr %016llx\n", addr); -- 2.7.4