diff options
| author | Akshay Adiga <akshay.adiga@linux.vnet.ibm.com> | 2016-08-04 20:59:17 +0530 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2016-08-06 14:52:26 +0200 |
| commit | 8e85946777d3f667085f298c0acfec12fe105078 (patch) | |
| tree | 4c594c36b1bcbe57482c7643dca4a6a89e20ec6a /drivers/cpufreq | |
| parent | 79ad70de539c58883098f9f4ed6312dd7f6c2fef (diff) | |
cpufreq: powernv: Fix crash in gpstate_timer_handler()
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 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: 09ca4c9b5958 (cpufreq: powernv: Replacing pstate_id with frequency table index)
Reported-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Akshay Adiga <akshay.adiga@linux.vnet.ibm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'drivers/cpufreq')
| -rw-r--r-- | drivers/cpufreq/powernv-cpufreq.c | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/drivers/cpufreq/powernv-cpufreq.c b/drivers/cpufreq/powernv-cpufreq.c index 0f138b050e9a..2fcc879d2b97 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 @@ -594,7 +613,7 @@ 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); } /* |