From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751304AbdBWQUW (ORCPT ); Thu, 23 Feb 2017 11:20:22 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:49762 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751049AbdBWQUV (ORCPT ); Thu, 23 Feb 2017 11:20:21 -0500 From: "Gautham R. Shenoy" To: Michael Ellerman , Benjamin Herrenschmidt , "Rafael J. Wysocki" , Daniel Lezcano , Michael Neuling , Vaidyanathan Srinivasan , "Shreyas B. Prabhu" , Shilpasri G Bhat , Balbir Singh Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, "Gautham R. Shenoy" Subject: [PATCH] powernv-cpuidle: Validate DT property arrays are of same size Date: Thu, 23 Feb 2017 21:49:44 +0530 X-Mailer: git-send-email 1.8.3.1 X-TM-AS-GCONF: 00 X-Content-Scanned: Fidelis XPS MAILER x-cbid: 17022316-8235-0000-0000-00000B092A63 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00006669; HX=3.00000240; KW=3.00000007; PH=3.00000004; SC=3.00000204; SDB=6.00826038; UDB=6.00404525; IPR=6.00603489; BA=6.00005168; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00014413; XFM=3.00000011; UTC=2017-02-23 16:20:09 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17022316-8236-0000-0000-000039D83A49 Message-Id: <1487866784-13410-1-git-send-email-ego@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-02-23_11:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=0 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1612050000 definitions=main-1702230152 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "Gautham R. Shenoy" The various properties associated with powernv idle states such as names, flags, residency-ns, latencies-ns, psscr, psscr-mask are exposed in the device-tree as property arrays such the pointwise entries in each of these arrays correspond to the properties of the same idle state. This patch validates that the lengths of the property arrays are the same. If there is a mismatch, the patch will ensure that we bail out and not expose the platform idle states via cpuidle. Signed-off-by: Gautham R. Shenoy --- drivers/cpuidle/cpuidle-powernv.c | 56 ++++++++++++++++++++++++++++++++++++--- 1 file changed, 53 insertions(+), 3 deletions(-) diff --git a/drivers/cpuidle/cpuidle-powernv.c b/drivers/cpuidle/cpuidle-powernv.c index 3705930..c30b9fd 100644 --- a/drivers/cpuidle/cpuidle-powernv.c +++ b/drivers/cpuidle/cpuidle-powernv.c @@ -197,11 +197,25 @@ static inline void add_powernv_state(int index, const char *name, stop_psscr_table[index].mask = psscr_mask; } +/* + * Returns 0 if prop1_len == prop2_len. Else returns -1 + */ +static inline int validate_dt_prop_sizes(const char *prop1, int prop1_len, + const char *prop2, int prop2_len) +{ + if (prop1_len == prop2_len) + return 0; + + pr_warn("cpuidle-powernv: array sizes don't match for %s and %s\n", + prop1, prop2); + return -1; +} + static int powernv_add_idle_states(void) { struct device_node *power_mgt; int nr_idle_states = 1; /* Snooze */ - int dt_idle_states; + int dt_idle_states, count; u32 latency_ns[CPUIDLE_STATE_MAX]; u32 residency_ns[CPUIDLE_STATE_MAX]; u32 flags[CPUIDLE_STATE_MAX]; @@ -226,6 +240,19 @@ static int powernv_add_idle_states(void) goto out; } + count = of_property_count_u32_elems(power_mgt, + "ibm,cpu-idle-state-latencies-ns"); + + if (validate_dt_prop_sizes("flags", dt_idle_states, + "latencies-ns", count) != 0) + goto out; + + count = of_property_count_strings(power_mgt, + "ibm,cpu-idle-state-names"); + if (validate_dt_prop_sizes("flags", dt_idle_states, + "names", count) != 0) + goto out; + /* * Since snooze is used as first idle state, max idle states allowed is * CPUIDLE_STATE_MAX -1 @@ -260,6 +287,18 @@ static int powernv_add_idle_states(void) has_stop_states = (flags[0] & (OPAL_PM_STOP_INST_FAST | OPAL_PM_STOP_INST_DEEP)); if (has_stop_states) { + count = of_property_count_u64_elems(power_mgt, + "ibm,cpu-idle-state-psscr"); + if (validate_dt_prop_sizes("flags", dt_idle_states, + "psscr", count) != 0) + goto out; + + count = of_property_count_u64_elems(power_mgt, + "ibm,cpu-idle-state-psscr-mask"); + if (validate_dt_prop_sizes("flags", dt_idle_states, + "psscr-mask", count) != 0) + goto out; + if (of_property_read_u64_array(power_mgt, "ibm,cpu-idle-state-psscr", psscr_val, dt_idle_states)) { pr_warn("cpuidle-powernv: missing ibm,cpu-idle-state-psscr in DT\n"); @@ -274,8 +313,19 @@ static int powernv_add_idle_states(void) } } - rc = of_property_read_u32_array(power_mgt, - "ibm,cpu-idle-state-residency-ns", residency_ns, dt_idle_states); + count = of_property_count_u32_elems(power_mgt, + "ibm,cpu-idle-state-residency-ns"); + + if (count < 0) { + rc = count; + } else if (validate_dt_prop_sizes("flags", dt_idle_states, + "psscr-mask", count) != 0) { + goto out; + } else { + rc = of_property_read_u32_array(power_mgt, + "ibm,cpu-idle-state-residency-ns", + residency_ns, dt_idle_states); + } for (i = 0; i < dt_idle_states; i++) { unsigned int exit_latency, target_residency; -- 1.9.4