From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964982AbcHDQrP (ORCPT ); Thu, 4 Aug 2016 12:47:15 -0400 Received: from mail-pa0-f49.google.com ([209.85.220.49]:35801 "EHLO mail-pa0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758718AbcHDQrN (ORCPT ); Thu, 4 Aug 2016 12:47:13 -0400 Date: Thu, 4 Aug 2016 09:47:11 -0700 From: Viresh Kumar To: Akshay Adiga Cc: rjw@rjwysocki.net, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Subject: Re: [PATCH] cpufreq: powernv: Fix crash in gpstate_timer_handler Message-ID: <20160804164711.GE10348@ubuntu> References: <1470324557-20711-1-git-send-email-akshay.adiga@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1470324557-20711-1-git-send-email-akshay.adiga@linux.vnet.ibm.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04-08-16, 20:59, Akshay Adiga wrote: > '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(-) Acked-by: Viresh Kumar -- viresh