diff mbox

cpufreq: powernv: Fix crash in gpstate_timer_handler

Message ID 1470324557-20711-1-git-send-email-akshay.adiga@linux.vnet.ibm.com (mailing list archive)
State Accepted, archived
Delegated to: Rafael Wysocki
Headers show

Commit Message

Akshay Adiga Aug. 4, 2016, 3:29 p.m. UTC
'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 <maddy@linux.vnet.ibm.com>
Signed-off-by: Akshay Adiga <akshay.adiga@linux.vnet.ibm.com>
---
 drivers/cpufreq/powernv-cpufreq.c | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

Comments

Viresh Kumar Aug. 4, 2016, 4:47 p.m. UTC | #1
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 <maddy@linux.vnet.ibm.com>
> Signed-off-by: Akshay Adiga <akshay.adiga@linux.vnet.ibm.com>
> ---
>  drivers/cpufreq/powernv-cpufreq.c | 21 ++++++++++++++++++++-
>  1 file changed, 20 insertions(+), 1 deletion(-)

Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Andrew Donnellan Aug. 5, 2016, 7:39 a.m. UTC | #2
On 05/08/16 01:29, 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 <maddy@linux.vnet.ibm.com>
> Signed-off-by: Akshay Adiga <akshay.adiga@linux.vnet.ibm.com>

Tested-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Michael Ellerman Aug. 10, 2016, 4:28 a.m. UTC | #3
Viresh Kumar <viresh.kumar@linaro.org> writes:

> 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 <maddy@linux.vnet.ibm.com>
>> Signed-off-by: Akshay Adiga <akshay.adiga@linux.vnet.ibm.com>
>> ---
>>  drivers/cpufreq/powernv-cpufreq.c | 21 ++++++++++++++++++++-
>>  1 file changed, 20 insertions(+), 1 deletion(-)
>
> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>

Who's merging this?

cheers
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Rafael J. Wysocki Aug. 10, 2016, 11:57 a.m. UTC | #4
On Wednesday, August 10, 2016 02:28:47 PM Michael Ellerman wrote:
> Viresh Kumar <viresh.kumar@linaro.org> writes:
> 
> > 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 <maddy@linux.vnet.ibm.com>
> >> Signed-off-by: Akshay Adiga <akshay.adiga@linux.vnet.ibm.com>
> >> ---
> >>  drivers/cpufreq/powernv-cpufreq.c | 21 ++++++++++++++++++++-
> >>  1 file changed, 20 insertions(+), 1 deletion(-)
> >
> > Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
> 
> Who's merging this?

I am.

Thanks,
Rafael

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Michael Ellerman Aug. 10, 2016, 12:41 p.m. UTC | #5
"Rafael J. Wysocki" <rjw@rjwysocki.net> writes:
> On Wednesday, August 10, 2016 02:28:47 PM Michael Ellerman wrote:
>> 
>> Who's merging this?
>
> I am.

Thanks!
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diff mbox

Patch

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);
 	}
 
 	/*