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=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_2 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 1CF7BC43603 for ; Tue, 17 Dec 2019 05:58:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E49592072D for ; Tue, 17 Dec 2019 05:58:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725836AbfLQF6s (ORCPT ); Tue, 17 Dec 2019 00:58:48 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:21436 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727124AbfLQF6s (ORCPT ); Tue, 17 Dec 2019 00:58:48 -0500 Received: from pps.filterd (m0098413.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id xBH5w5Em028408; Tue, 17 Dec 2019 00:58:29 -0500 Received: from pps.reinject (localhost [127.0.0.1]) by mx0b-001b2d01.pphosted.com with ESMTP id 2wxfgsr62d-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 17 Dec 2019 00:58:29 -0500 Received: from m0098413.ppops.net (m0098413.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.36/8.16.0.36) with SMTP id xBH5wTf9029419; Tue, 17 Dec 2019 00:58:29 -0500 Received: from ppma04wdc.us.ibm.com (1a.90.2fa9.ip4.static.sl-reverse.com [169.47.144.26]) by mx0b-001b2d01.pphosted.com with ESMTP id 2wxfgsr626-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 17 Dec 2019 00:58:29 -0500 Received: from pps.filterd (ppma04wdc.us.ibm.com [127.0.0.1]) by ppma04wdc.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id xBH5tapp030662; Tue, 17 Dec 2019 05:58:28 GMT Received: from b03cxnp07028.gho.boulder.ibm.com (b03cxnp07028.gho.boulder.ibm.com [9.17.130.15]) by ppma04wdc.us.ibm.com with ESMTP id 2wvqc69ger-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 17 Dec 2019 05:58:28 +0000 Received: from b03ledav006.gho.boulder.ibm.com (b03ledav006.gho.boulder.ibm.com [9.17.130.237]) by b03cxnp07028.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id xBH5wRlb31195556 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 17 Dec 2019 05:58:28 GMT Received: from b03ledav006.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id DB9C0C605D; Tue, 17 Dec 2019 05:58:27 +0000 (GMT) Received: from b03ledav006.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 7843AC6055; Tue, 17 Dec 2019 05:58:27 +0000 (GMT) Received: from [9.70.82.143] (unknown [9.70.82.143]) by b03ledav006.gho.boulder.ibm.com (Postfix) with ESMTP; Tue, 17 Dec 2019 05:58:27 +0000 (GMT) Subject: [PATCH V3 08/13] powerpc/vas: Update CSB and notify process for fault CRBs From: Haren Myneni To: mpe@ellerman.id.au Cc: hch@infradead.org, devicetree@vger.kernel.org, mikey@neuling.org, herbert@gondor.apana.org.au, npiggin@gmail.com, linuxppc-dev@lists.ozlabs.org, sukadev@linux.vnet.ibm.com In-Reply-To: <1576561080.16318.6531.camel@hbabu-laptop> References: <1576561080.16318.6531.camel@hbabu-laptop> Content-Type: text/plain; charset="UTF-8" Date: Mon, 16 Dec 2019 21:56:35 -0800 Message-ID: <1576562195.16318.6542.camel@hbabu-laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.95,18.0.572 definitions=2019-12-17_01:2019-12-16,2019-12-16 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxlogscore=785 mlxscore=0 clxscore=1015 impostorscore=0 bulkscore=0 phishscore=0 adultscore=0 spamscore=0 lowpriorityscore=0 priorityscore=1501 malwarescore=0 suspectscore=1 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-1910280000 definitions=main-1912170053 Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org For each fault CRB, update fault address in CRB (fault_storage_addr) and translation error status in CSB so that user space can touch the fault address and resend the request. If the user space passed invalid CSB address send signal to process with SIGSEGV. Signed-off-by: Sukadev Bhattiprolu Signed-off-by: Haren Myneni --- arch/powerpc/platforms/powernv/vas-fault.c | 121 +++++++++++++++++++++++++++++ 1 file changed, 121 insertions(+) diff --git a/arch/powerpc/platforms/powernv/vas-fault.c b/arch/powerpc/platforms/powernv/vas-fault.c index 57f21ea..45bea15c 100644 --- a/arch/powerpc/platforms/powernv/vas-fault.c +++ b/arch/powerpc/platforms/powernv/vas-fault.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include @@ -26,6 +27,125 @@ #define VAS_FAULT_WIN_FIFO_SIZE (4 << 20) /* + * Update the CSB to indicate a translation error. + * + * If the fault is in the CSB address itself or if we are unable to + * update the CSB, send a signal to the process, because we have no + * other way of notifying the user process. + * + * Remaining settings in the CSB are based on wait_for_csb() of + * NX-GZIP. + */ +static void update_csb(struct vas_window *window, + struct coprocessor_request_block *crb) +{ + int rc; + struct pid *pid; + void __user *csb_addr; + struct task_struct *tsk; + struct kernel_siginfo info; + struct coprocessor_status_block csb; + + /* + * NX user space windows can not be opened for task->mm=NULL + * and faults will not be generated for kernel requests. + */ + if (!window->mm || !window->user_win) + return; + + csb_addr = (void *)be64_to_cpu(crb->csb_addr); + + csb.cc = CSB_CC_TRANSLATION; + csb.ce = CSB_CE_TERMINATION; + csb.cs = 0; + csb.count = 0; + + /* + * Returns the fault address in CPU format since it is passed with + * signal. But if the user space expects BE format, need changes. + * i.e either kernel (here) or user should convert to CPU format. + * Not both! + */ + csb.address = be64_to_cpu(crb->stamp.nx.fault_storage_addr); + csb.flags = 0; + + use_mm(window->mm); + rc = copy_to_user(csb_addr, &csb, sizeof(csb)); + /* + * User space polls on csb.flags (first byte). So add barrier + * then copy first byte with csb flags update. + */ + smp_mb(); + if (!rc) { + csb.flags = CSB_V; + rc = copy_to_user(csb_addr, &csb, sizeof(u8)); + } + unuse_mm(window->mm); + + /* Success */ + if (!rc) + return; + + /* + * User space passed invalid CSB address, Notify process with + * SEGV signal. + */ + pid = window->pid; + tsk = get_pid_task(pid, PIDTYPE_PID); + /* + * Send window will be closed after processing all NX requests + * and process exits after closing all windows. In multi-thread + * applications, thread may not exists, but does not close FD + * (means send window) upon exit. Parent thread (tgid) can use + * and close the window later. + * pid and mm references are taken when window is opened by + * process (pid). So tgid is used only when child thread is not + * available in multithread tasks. + * + */ + if (!tsk) { + pid = window->tgid; + tsk = get_pid_task(pid, PIDTYPE_PID); + /* + * Parent thread will be closing window during its exit. + * So should not get here. + */ + if (!tsk) + return; + } + + /* Do not notify if the task is exiting. */ + if (tsk->flags & PF_EXITING) { + put_task_struct(tsk); + return; + } + put_task_struct(tsk); + + pr_err("Invalid CSB address 0x%p signalling pid(%d)\n", + csb_addr, pid_vnr(pid)); + + clear_siginfo(&info); + info.si_signo = SIGSEGV; + info.si_errno = EFAULT; + info.si_code = SEGV_MAPERR; + info.si_addr = csb_addr; + + /* + * process will be polling on csb.flags after request is sent to + * NX. So generally CSB update should not fail except when an + * application does not follow the process properly. So an error + * message will be displayed and leave it to user space whether + * to ignore or handle this signal. + */ + rcu_read_lock(); + rc = kill_pid_info(SIGSEGV, &info, pid); + rcu_read_unlock(); + + pr_devel("%s(): pid %d kill_proc_info() rc %d\n", __func__, + pid_vnr(pid), rc); +} + +/* * Process CRBs that we receive on the fault window. */ irqreturn_t vas_fault_handler(int irq, void *data) @@ -102,6 +222,7 @@ irqreturn_t vas_fault_handler(int irq, void *data) return IRQ_HANDLED; } + update_csb(window, crb); } while (true); return IRQ_HANDLED; -- 1.8.3.1 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=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_2 autolearn=unavailable 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 D8782C43603 for ; Tue, 17 Dec 2019 06:09:02 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 556122082E for ; Tue, 17 Dec 2019 06:09:02 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 556122082E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.ibm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 47cSQ34QcXzDqZp for ; Tue, 17 Dec 2019 17:08:59 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=linux.ibm.com (client-ip=148.163.158.5; helo=mx0a-001b2d01.pphosted.com; envelope-from=haren@linux.ibm.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.ibm.com Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) (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 47cSBB75G6zDqCF for ; Tue, 17 Dec 2019 16:58:42 +1100 (AEDT) Received: from pps.filterd (m0098413.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id xBH5w5Em028408; Tue, 17 Dec 2019 00:58:29 -0500 Received: from pps.reinject (localhost [127.0.0.1]) by mx0b-001b2d01.pphosted.com with ESMTP id 2wxfgsr62d-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 17 Dec 2019 00:58:29 -0500 Received: from m0098413.ppops.net (m0098413.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.36/8.16.0.36) with SMTP id xBH5wTf9029419; Tue, 17 Dec 2019 00:58:29 -0500 Received: from ppma04wdc.us.ibm.com (1a.90.2fa9.ip4.static.sl-reverse.com [169.47.144.26]) by mx0b-001b2d01.pphosted.com with ESMTP id 2wxfgsr626-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 17 Dec 2019 00:58:29 -0500 Received: from pps.filterd (ppma04wdc.us.ibm.com [127.0.0.1]) by ppma04wdc.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id xBH5tapp030662; Tue, 17 Dec 2019 05:58:28 GMT Received: from b03cxnp07028.gho.boulder.ibm.com (b03cxnp07028.gho.boulder.ibm.com [9.17.130.15]) by ppma04wdc.us.ibm.com with ESMTP id 2wvqc69ger-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 17 Dec 2019 05:58:28 +0000 Received: from b03ledav006.gho.boulder.ibm.com (b03ledav006.gho.boulder.ibm.com [9.17.130.237]) by b03cxnp07028.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id xBH5wRlb31195556 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 17 Dec 2019 05:58:28 GMT Received: from b03ledav006.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id DB9C0C605D; Tue, 17 Dec 2019 05:58:27 +0000 (GMT) Received: from b03ledav006.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 7843AC6055; Tue, 17 Dec 2019 05:58:27 +0000 (GMT) Received: from [9.70.82.143] (unknown [9.70.82.143]) by b03ledav006.gho.boulder.ibm.com (Postfix) with ESMTP; Tue, 17 Dec 2019 05:58:27 +0000 (GMT) Subject: [PATCH V3 08/13] powerpc/vas: Update CSB and notify process for fault CRBs From: Haren Myneni To: mpe@ellerman.id.au In-Reply-To: <1576561080.16318.6531.camel@hbabu-laptop> References: <1576561080.16318.6531.camel@hbabu-laptop> Content-Type: text/plain; charset="UTF-8" Date: Mon, 16 Dec 2019 21:56:35 -0800 Message-ID: <1576562195.16318.6542.camel@hbabu-laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.95,18.0.572 definitions=2019-12-17_01:2019-12-16,2019-12-16 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxlogscore=785 mlxscore=0 clxscore=1015 impostorscore=0 bulkscore=0 phishscore=0 adultscore=0 spamscore=0 lowpriorityscore=0 priorityscore=1501 malwarescore=0 suspectscore=1 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-1910280000 definitions=main-1912170053 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: devicetree@vger.kernel.org, mikey@neuling.org, herbert@gondor.apana.org.au, npiggin@gmail.com, hch@infradead.org, sukadev@linux.vnet.ibm.com, linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" For each fault CRB, update fault address in CRB (fault_storage_addr) and translation error status in CSB so that user space can touch the fault address and resend the request. If the user space passed invalid CSB address send signal to process with SIGSEGV. Signed-off-by: Sukadev Bhattiprolu Signed-off-by: Haren Myneni --- arch/powerpc/platforms/powernv/vas-fault.c | 121 +++++++++++++++++++++++++++++ 1 file changed, 121 insertions(+) diff --git a/arch/powerpc/platforms/powernv/vas-fault.c b/arch/powerpc/platforms/powernv/vas-fault.c index 57f21ea..45bea15c 100644 --- a/arch/powerpc/platforms/powernv/vas-fault.c +++ b/arch/powerpc/platforms/powernv/vas-fault.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include @@ -26,6 +27,125 @@ #define VAS_FAULT_WIN_FIFO_SIZE (4 << 20) /* + * Update the CSB to indicate a translation error. + * + * If the fault is in the CSB address itself or if we are unable to + * update the CSB, send a signal to the process, because we have no + * other way of notifying the user process. + * + * Remaining settings in the CSB are based on wait_for_csb() of + * NX-GZIP. + */ +static void update_csb(struct vas_window *window, + struct coprocessor_request_block *crb) +{ + int rc; + struct pid *pid; + void __user *csb_addr; + struct task_struct *tsk; + struct kernel_siginfo info; + struct coprocessor_status_block csb; + + /* + * NX user space windows can not be opened for task->mm=NULL + * and faults will not be generated for kernel requests. + */ + if (!window->mm || !window->user_win) + return; + + csb_addr = (void *)be64_to_cpu(crb->csb_addr); + + csb.cc = CSB_CC_TRANSLATION; + csb.ce = CSB_CE_TERMINATION; + csb.cs = 0; + csb.count = 0; + + /* + * Returns the fault address in CPU format since it is passed with + * signal. But if the user space expects BE format, need changes. + * i.e either kernel (here) or user should convert to CPU format. + * Not both! + */ + csb.address = be64_to_cpu(crb->stamp.nx.fault_storage_addr); + csb.flags = 0; + + use_mm(window->mm); + rc = copy_to_user(csb_addr, &csb, sizeof(csb)); + /* + * User space polls on csb.flags (first byte). So add barrier + * then copy first byte with csb flags update. + */ + smp_mb(); + if (!rc) { + csb.flags = CSB_V; + rc = copy_to_user(csb_addr, &csb, sizeof(u8)); + } + unuse_mm(window->mm); + + /* Success */ + if (!rc) + return; + + /* + * User space passed invalid CSB address, Notify process with + * SEGV signal. + */ + pid = window->pid; + tsk = get_pid_task(pid, PIDTYPE_PID); + /* + * Send window will be closed after processing all NX requests + * and process exits after closing all windows. In multi-thread + * applications, thread may not exists, but does not close FD + * (means send window) upon exit. Parent thread (tgid) can use + * and close the window later. + * pid and mm references are taken when window is opened by + * process (pid). So tgid is used only when child thread is not + * available in multithread tasks. + * + */ + if (!tsk) { + pid = window->tgid; + tsk = get_pid_task(pid, PIDTYPE_PID); + /* + * Parent thread will be closing window during its exit. + * So should not get here. + */ + if (!tsk) + return; + } + + /* Do not notify if the task is exiting. */ + if (tsk->flags & PF_EXITING) { + put_task_struct(tsk); + return; + } + put_task_struct(tsk); + + pr_err("Invalid CSB address 0x%p signalling pid(%d)\n", + csb_addr, pid_vnr(pid)); + + clear_siginfo(&info); + info.si_signo = SIGSEGV; + info.si_errno = EFAULT; + info.si_code = SEGV_MAPERR; + info.si_addr = csb_addr; + + /* + * process will be polling on csb.flags after request is sent to + * NX. So generally CSB update should not fail except when an + * application does not follow the process properly. So an error + * message will be displayed and leave it to user space whether + * to ignore or handle this signal. + */ + rcu_read_lock(); + rc = kill_pid_info(SIGSEGV, &info, pid); + rcu_read_unlock(); + + pr_devel("%s(): pid %d kill_proc_info() rc %d\n", __func__, + pid_vnr(pid), rc); +} + +/* * Process CRBs that we receive on the fault window. */ irqreturn_t vas_fault_handler(int irq, void *data) @@ -102,6 +222,7 @@ irqreturn_t vas_fault_handler(int irq, void *data) return IRQ_HANDLED; } + update_csb(window, crb); } while (true); return IRQ_HANDLED; -- 1.8.3.1