From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: 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 3s4v5972PJzDqS9 for ; Fri, 5 Aug 2016 01:30:05 +1000 (AEST) Received: from pps.filterd (m0098413.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.11/8.16.0.11) with SMTP id u74FO7Na036691 for ; Thu, 4 Aug 2016 11:30:03 -0400 Received: from e28smtp01.in.ibm.com (e28smtp01.in.ibm.com [125.16.236.1]) by mx0b-001b2d01.pphosted.com with ESMTP id 24kkajk5nt-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Thu, 04 Aug 2016 11:30:03 -0400 Received: from localhost by e28smtp01.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 4 Aug 2016 20:59:58 +0530 Received: from d28relay02.in.ibm.com (d28relay02.in.ibm.com [9.184.220.59]) by d28dlp03.in.ibm.com (Postfix) with ESMTP id 5E3B81258026 for ; Thu, 4 Aug 2016 21:03:00 +0530 (IST) Received: from d28av03.in.ibm.com (d28av03.in.ibm.com [9.184.220.65]) by d28relay02.in.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id u74FTiex17957258 for ; Thu, 4 Aug 2016 20:59:44 +0530 Received: from d28av03.in.ibm.com (localhost [127.0.0.1]) by d28av03.in.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id u74FTqZa021460 for ; Thu, 4 Aug 2016 20:59:54 +0530 From: Akshay Adiga To: rjw@rjwysocki.net, viresh.kumar@linaro.org, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Cc: Akshay Adiga Subject: [PATCH] cpufreq: powernv: Fix crash in gpstate_timer_handler Date: Thu, 4 Aug 2016 20:59:17 +0530 Message-Id: <1470324557-20711-1-git-send-email-akshay.adiga@linux.vnet.ibm.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 'commit 09ca4c9b5958 ("cpufreq: powernv: Replacing pstate_id with frequency table index")' changes calc_global_pstate() to use cpufreq_table index instead of pstate_id. But in gpstate_timer_handler() pstate_id was being passed instead of cpufreq_table index, which caused the index_to_pstate() to access out of bound indices, leading to this crash. Adding sanity check for index and pstate, to ensure only valid pstate and index values are returned. Call Trace: [c00000078d66b130] [c00000000011d224] __free_irq+0x234/0x360 (unreliable) [c00000078d66b1c0] [c00000000011d44c] free_irq+0x6c/0xa0 [c00000078d66b1f0] [c00000000006c4f8] opal_event_shutdown+0x88/0xd0 [c00000078d66b230] [c000000000067a4c] opal_shutdown+0x1c/0x90 [c00000078d66b260] [c000000000063a00] pnv_shutdown+0x20/0x40 [c00000078d66b280] [c000000000021538] machine_restart+0x38/0x90 [c0000000078d66b310] [c000000000965ea0] panic+0x284/0x300 [c00000078d66b3a0] [c00000000001f508] die+0x388/0x450 [c00000078d66b430] [c000000000045a50] bad_page_fault+0xd0/0x140 [c00000078d66b4a0] [c000000000008964] handle_page_fault+0x2c/0x30 interrupt: 300 at gpstate_timer_handler+0x150/0x260 LR = gpstate_timer_handler+0x130/0x260 [c00000078d66b7f0] [c000000000132b58] call_timer_fn+0x58/0x1c0 [c00000078d66b880] [c000000000132e20] expire_timers+0x130/0x1d0 [c00000078d66b8f0] [c000000000133068] run_timer_softirq+0x1a8/0x230 [c00000078d66b980] [c0000000000b535c] __do_softirq+0x18c/0x400 [c00000078d66ba70] [c0000000000b5828] irq_exit+0xc8/0x100 [c00000078d66ba90] [c00000000001e214] timer_interrupt+0xa4/0xe0 [c00000078d66bac0] [c0000000000027d0] decrementer_common+0x150/0x180 interrupt: 901 at arch_local_irq_restore+0x74/0x90 0] [c000000000106b34] call_cpuidle+0x44/0x90 [c00000078d66be50] [c00000000010708c] cpu_startup_entry+0x38c/0x460 [c00000078d66bf20] [c00000000003d930] start_secondary+0x330/0x380 [c00000078d66bf90] [c000000000008e6c] start_secondary_prolog+0x10/0x14 Fixes: 08d27eb ("cpufreq: powernv: Replacing pstate_id with frequency table index") Reported-by: Madhavan Srinivasan Signed-off-by: Akshay Adiga --- drivers/cpufreq/powernv-cpufreq.c | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-) diff --git a/drivers/cpufreq/powernv-cpufreq.c b/drivers/cpufreq/powernv-cpufreq.c index 87796e0..d3ffde8 100644 --- a/drivers/cpufreq/powernv-cpufreq.c +++ b/drivers/cpufreq/powernv-cpufreq.c @@ -145,11 +145,30 @@ static struct powernv_pstate_info { /* Use following macros for conversions between pstate_id and index */ static inline int idx_to_pstate(unsigned int i) { + if (unlikely(i >= powernv_pstate_info.nr_pstates)) { + pr_warn_once("index %u is out of bound\n", i); + return powernv_freqs[powernv_pstate_info.nominal].driver_data; + } + return powernv_freqs[i].driver_data; } static inline unsigned int pstate_to_idx(int pstate) { + int min = powernv_freqs[powernv_pstate_info.min].driver_data; + int max = powernv_freqs[powernv_pstate_info.max].driver_data; + + if (min > 0) { + if (unlikely((pstate < max) || (pstate > min))) { + pr_warn_once("pstate %d is out of bound\n", pstate); + return powernv_pstate_info.nominal; + } + } else { + if (unlikely((pstate > max) || (pstate < min))) { + pr_warn_once("pstate %d is out of bound\n", pstate); + return powernv_pstate_info.nominal; + } + } /* * abs() is deliberately used so that is works with * both monotonically increasing and decreasing @@ -593,7 +612,7 @@ void gpstate_timer_handler(unsigned long data) } else { gpstate_idx = calc_global_pstate(gpstates->elapsed_time, gpstates->highest_lpstate_idx, - freq_data.pstate_id); + gpstates->last_lpstate_idx); } /* -- 2.1.4