linux-toradex.git/drivers/cpufreq, branch v4.4.73 Linux kernel for Apalis and Colibri modules cpufreq: cpufreq_register_driver() should return -ENODEV if init fails 2017-06-14T11:16:23+00:00 David Arcari darcari@redhat.com 2017-05-26T15:37:31+00:00 94d3dafe96f321dfe5e7c3542f1c00c4125984b4 commit 6c77003677d5f1ce15f26d24360cb66c0bc07bb3 upstream. For a driver that does not set the CPUFREQ_STICKY flag, if all of the ->init() calls fail, cpufreq_register_driver() should return an error. This will prevent the driver from loading. Fixes: ce1bcfe94db8 (cpufreq: check cpufreq_policy_list instead of scanning policies for all CPUs) Signed-off-by: David Arcari <darcari@redhat.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 6c77003677d5f1ce15f26d24360cb66c0bc07bb3 upstream.

For a driver that does not set the CPUFREQ_STICKY flag, if all of the
->init() calls fail, cpufreq_register_driver() should return an error.
This will prevent the driver from loading.

Fixes: ce1bcfe94db8 (cpufreq: check cpufreq_policy_list instead of scanning policies for all CPUs)
Signed-off-by: David Arcari <darcari@redhat.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cpufreq: Restore policy min/max limits on CPU online 2017-03-30T07:35:18+00:00 Viresh Kumar viresh.kumar@linaro.org 2017-03-21T06:06:06+00:00 17503963206584333b674740ba75b5079ea7e196 commit ff010472fb75670cb5c08671e820eeea3af59c87 upstream. On CPU online the cpufreq core restores the previous governor (or the previous "policy" setting for ->setpolicy drivers), but it does not restore the min/max limits at the same time, which is confusing, inconsistent and real pain for users who set the limits and then suspend/resume the system (using full suspend), in which case the limits are reset on all CPUs except for the boot one. Fix this by making cpufreq_online() restore the limits when an inactive policy is brought online. The commit log and patch are inspired from Rafael's earlier work. Reported-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit ff010472fb75670cb5c08671e820eeea3af59c87 upstream.

On CPU online the cpufreq core restores the previous governor (or
the previous "policy" setting for ->setpolicy drivers), but it does
not restore the min/max limits at the same time, which is confusing,
inconsistent and real pain for users who set the limits and then
suspend/resume the system (using full suspend), in which case the
limits are reset on all CPUs except for the boot one.

Fix this by making cpufreq_online() restore the limits when an inactive
policy is brought online.

The commit log and patch are inspired from Rafael's earlier work.

Reported-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cpufreq: Fix and clean up show_cpuinfo_cur_freq() 2017-03-26T10:13:19+00:00 Rafael J. Wysocki rafael.j.wysocki@intel.com 2017-03-14T23:12:16+00:00 09875d1393d4589bcdfeeba8747a12dd69810cc9 commit 9b4f603e7a9f4282aec451063ffbbb8bb410dcd9 upstream. There is a missing newline in show_cpuinfo_cur_freq(), so add it, but while at it clean that function up somewhat too. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 9b4f603e7a9f4282aec451063ffbbb8bb410dcd9 upstream.

There is a missing newline in show_cpuinfo_cur_freq(), so add it,
but while at it clean that function up somewhat too.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cpufreq: powernv: Disable preemption while checking CPU throttling state 2017-01-19T19:17:22+00:00 Denis Kirjanov kda@linux-powerpc.org 2016-11-08T10:39:28+00:00 2c1dd423a5671f6301b583cc0edd0069263c7157 commit 8a10c06a20ec8097a68fd7a4a1c0e285095b4d2f upstream. With preemption turned on we can read incorrect throttling state while being switched to CPU on a different chip. BUG: using smp_processor_id() in preemptible [00000000] code: cat/7343 caller is .powernv_cpufreq_throttle_check+0x2c/0x710 CPU: 13 PID: 7343 Comm: cat Not tainted 4.8.0-rc5-dirty #1 Call Trace: [c0000007d25b75b0] [c000000000971378] .dump_stack+0xe4/0x150 (unreliable) [c0000007d25b7640] [c0000000005162e4] .check_preemption_disabled+0x134/0x150 [c0000007d25b76e0] [c0000000007b63ac] .powernv_cpufreq_throttle_check+0x2c/0x710 [c0000007d25b7790] [c0000000007b6d18] .powernv_cpufreq_target_index+0x288/0x360 [c0000007d25b7870] [c0000000007acee4] .__cpufreq_driver_target+0x394/0x8c0 [c0000007d25b7920] [c0000000007b22ac] .cpufreq_set+0x7c/0xd0 [c0000007d25b79b0] [c0000000007adf50] .store_scaling_setspeed+0x80/0xc0 [c0000007d25b7a40] [c0000000007ae270] .store+0xa0/0x100 [c0000007d25b7ae0] [c0000000003566e8] .sysfs_kf_write+0x88/0xb0 [c0000007d25b7b70] [c0000000003553b8] .kernfs_fop_write+0x178/0x260 [c0000007d25b7c10] [c0000000002ac3cc] .__vfs_write+0x3c/0x1c0 [c0000007d25b7cf0] [c0000000002ad584] .vfs_write+0xc4/0x230 [c0000007d25b7d90] [c0000000002aeef8] .SyS_write+0x58/0x100 [c0000007d25b7e30] [c00000000000bfec] system_call+0x38/0xfc Fixes: 09a972d16209 (cpufreq: powernv: Report cpu frequency throttling) Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com> Signed-off-by: Denis Kirjanov <kda@linux-powerpc.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 8a10c06a20ec8097a68fd7a4a1c0e285095b4d2f upstream.

With preemption turned on we can read incorrect throttling state
while being switched to CPU on a different chip.

 BUG: using smp_processor_id() in preemptible [00000000] code: cat/7343
 caller is .powernv_cpufreq_throttle_check+0x2c/0x710
 CPU: 13 PID: 7343 Comm: cat Not tainted 4.8.0-rc5-dirty #1
 Call Trace:
 [c0000007d25b75b0] [c000000000971378] .dump_stack+0xe4/0x150 (unreliable)
 [c0000007d25b7640] [c0000000005162e4] .check_preemption_disabled+0x134/0x150
 [c0000007d25b76e0] [c0000000007b63ac] .powernv_cpufreq_throttle_check+0x2c/0x710
 [c0000007d25b7790] [c0000000007b6d18] .powernv_cpufreq_target_index+0x288/0x360
 [c0000007d25b7870] [c0000000007acee4] .__cpufreq_driver_target+0x394/0x8c0
 [c0000007d25b7920] [c0000000007b22ac] .cpufreq_set+0x7c/0xd0
 [c0000007d25b79b0] [c0000000007adf50] .store_scaling_setspeed+0x80/0xc0
 [c0000007d25b7a40] [c0000000007ae270] .store+0xa0/0x100
 [c0000007d25b7ae0] [c0000000003566e8] .sysfs_kf_write+0x88/0xb0
 [c0000007d25b7b70] [c0000000003553b8] .kernfs_fop_write+0x178/0x260
 [c0000007d25b7c10] [c0000000002ac3cc] .__vfs_write+0x3c/0x1c0
 [c0000007d25b7cf0] [c0000000002ad584] .vfs_write+0xc4/0x230
 [c0000007d25b7d90] [c0000000002aeef8] .SyS_write+0x58/0x100
 [c0000007d25b7e30] [c00000000000bfec] system_call+0x38/0xfc

Fixes: 09a972d16209 (cpufreq: powernv: Report cpu frequency throttling)
Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Denis Kirjanov <kda@linux-powerpc.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cpufreq: intel_pstate: Fix unsafe HWP MSR access 2016-10-28T07:01:26+00:00 Srinivas Pandruvada srinivas.pandruvada@linux.intel.com 2016-10-08T19:42:38+00:00 d756b52c8bbe7735cc881dab46378518d2d4b1f1 commit f9f4872df6e1801572949f8a370c886122d4b6da upstream. This is a requirement that MSR MSR_PM_ENABLE must be set to 0x01 before reading MSR_HWP_CAPABILITIES on a given CPU. If cpufreq init() is scheduled on a CPU which is not same as policy->cpu or migrates to a different CPU before calling msr read for MSR_HWP_CAPABILITIES, it is possible that MSR_PM_ENABLE was not to set to 0x01 on that CPU. This will cause GP fault. So like other places in this path rdmsrl_on_cpu should be used instead of rdmsrl. Moreover the scope of MSR_HWP_CAPABILITIES is on per thread basis, so it should be read from the same CPU, for which MSR MSR_HWP_REQUEST is getting set. dmesg dump or warning: [ 22.014488] WARNING: CPU: 139 PID: 1 at arch/x86/mm/extable.c:50 ex_handler_rdmsr_unsafe+0x68/0x70 [ 22.014492] unchecked MSR access error: RDMSR from 0x771 [ 22.014493] Modules linked in: [ 22.014507] CPU: 139 PID: 1 Comm: swapper/0 Not tainted 4.7.5+ #1 ... ... [ 22.014516] Call Trace: [ 22.014542] [<ffffffff813d7dd1>] dump_stack+0x63/0x82 [ 22.014558] [<ffffffff8107bc8b>] __warn+0xcb/0xf0 [ 22.014561] [<ffffffff8107bcff>] warn_slowpath_fmt+0x4f/0x60 [ 22.014563] [<ffffffff810676f8>] ex_handler_rdmsr_unsafe+0x68/0x70 [ 22.014564] [<ffffffff810677d9>] fixup_exception+0x39/0x50 [ 22.014604] [<ffffffff8102e400>] do_general_protection+0x80/0x150 [ 22.014610] [<ffffffff817f9ec8>] general_protection+0x28/0x30 [ 22.014635] [<ffffffff81687940>] ? get_target_pstate_use_performance+0xb0/0xb0 [ 22.014642] [<ffffffff810600c7>] ? native_read_msr+0x7/0x40 [ 22.014657] [<ffffffff81688123>] intel_pstate_hwp_set+0x23/0x130 [ 22.014660] [<ffffffff81688406>] intel_pstate_set_policy+0x1b6/0x340 [ 22.014662] [<ffffffff816829bb>] cpufreq_set_policy+0xeb/0x2c0 [ 22.014664] [<ffffffff81682f39>] cpufreq_init_policy+0x79/0xe0 [ 22.014666] [<ffffffff81682cb0>] ? cpufreq_update_policy+0x120/0x120 [ 22.014669] [<ffffffff816833a6>] cpufreq_online+0x406/0x820 [ 22.014671] [<ffffffff8168381f>] cpufreq_add_dev+0x5f/0x90 [ 22.014717] [<ffffffff81530ac8>] subsys_interface_register+0xb8/0x100 [ 22.014719] [<ffffffff816821bc>] cpufreq_register_driver+0x14c/0x210 [ 22.014749] [<ffffffff81fe1d90>] intel_pstate_init+0x39d/0x4d5 [ 22.014751] [<ffffffff81fe13f2>] ? cpufreq_gov_dbs_init+0x12/0x12 Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit f9f4872df6e1801572949f8a370c886122d4b6da upstream.

This is a requirement that MSR MSR_PM_ENABLE must be set to 0x01 before
reading MSR_HWP_CAPABILITIES on a given CPU. If cpufreq init() is
scheduled on a CPU which is not same as policy->cpu or migrates to a
different CPU before calling msr read for MSR_HWP_CAPABILITIES, it
is possible that MSR_PM_ENABLE was not to set to 0x01 on that CPU.
This will cause GP fault. So like other places in this path
rdmsrl_on_cpu should be used instead of rdmsrl.

Moreover the scope of MSR_HWP_CAPABILITIES is on per thread basis, so it
should be read from the same CPU, for which MSR MSR_HWP_REQUEST is
getting set.

dmesg dump or warning:

[   22.014488] WARNING: CPU: 139 PID: 1 at arch/x86/mm/extable.c:50 ex_handler_rdmsr_unsafe+0x68/0x70
[   22.014492] unchecked MSR access error: RDMSR from 0x771
[   22.014493] Modules linked in:
[   22.014507] CPU: 139 PID: 1 Comm: swapper/0 Not tainted 4.7.5+ #1
...
...
[   22.014516] Call Trace:
[   22.014542]  [<ffffffff813d7dd1>] dump_stack+0x63/0x82
[   22.014558]  [<ffffffff8107bc8b>] __warn+0xcb/0xf0
[   22.014561]  [<ffffffff8107bcff>] warn_slowpath_fmt+0x4f/0x60
[   22.014563]  [<ffffffff810676f8>] ex_handler_rdmsr_unsafe+0x68/0x70
[   22.014564]  [<ffffffff810677d9>] fixup_exception+0x39/0x50
[   22.014604]  [<ffffffff8102e400>] do_general_protection+0x80/0x150
[   22.014610]  [<ffffffff817f9ec8>] general_protection+0x28/0x30
[   22.014635]  [<ffffffff81687940>] ? get_target_pstate_use_performance+0xb0/0xb0
[   22.014642]  [<ffffffff810600c7>] ? native_read_msr+0x7/0x40
[   22.014657]  [<ffffffff81688123>] intel_pstate_hwp_set+0x23/0x130
[   22.014660]  [<ffffffff81688406>] intel_pstate_set_policy+0x1b6/0x340
[   22.014662]  [<ffffffff816829bb>] cpufreq_set_policy+0xeb/0x2c0
[   22.014664]  [<ffffffff81682f39>] cpufreq_init_policy+0x79/0xe0
[   22.014666]  [<ffffffff81682cb0>] ? cpufreq_update_policy+0x120/0x120
[   22.014669]  [<ffffffff816833a6>] cpufreq_online+0x406/0x820
[   22.014671]  [<ffffffff8168381f>] cpufreq_add_dev+0x5f/0x90
[   22.014717]  [<ffffffff81530ac8>] subsys_interface_register+0xb8/0x100
[   22.014719]  [<ffffffff816821bc>] cpufreq_register_driver+0x14c/0x210
[   22.014749]  [<ffffffff81fe1d90>] intel_pstate_init+0x39d/0x4d5
[   22.014751]  [<ffffffff81fe13f2>] ? cpufreq_gov_dbs_init+0x12/0x12

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cpufreq: Fix GOV_LIMITS handling for the userspace governor 2016-09-15T06:27:54+00:00 Sai Gurrappadi sgurrappadi@nvidia.com 2016-04-29T21:44:37+00:00 aaac8cab2f92aa235f6f79e8cff52bf11c0fbf1d commit e43e94c1eda76dabd686ddf6f7825f54d747b310 upstream. Currently, the userspace governor only updates frequency on GOV_LIMITS if policy->cur falls outside policy->{min/max}. However, it is also necessary to update current frequency on GOV_LIMITS to match the user requested value if it can be achieved within the new policy->{max/min}. This was previously the behaviour in the governor until commit d1922f0 ("cpufreq: Simplify userspace governor") which incorrectly assumed that policy->cur == user requested frequency via scaling_setspeed. This won't be true if the user requested frequency falls outside policy->{min/max}. Ex: a temporary thermal cap throttled the user requested frequency. Fix this by storing the user requested frequency in a seperate variable. The governor will then try to achieve this request on every GOV_LIMITS change. Fixes: d1922f02562f (cpufreq: Simplify userspace governor) Signed-off-by: Sai Gurrappadi <sgurrappadi@nvidia.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit e43e94c1eda76dabd686ddf6f7825f54d747b310 upstream.

Currently, the userspace governor only updates frequency on GOV_LIMITS
if policy->cur falls outside policy->{min/max}. However, it is also
necessary to update current frequency on GOV_LIMITS to match the user
requested value if it can be achieved within the new policy->{max/min}.

This was previously the behaviour in the governor until commit d1922f0
("cpufreq: Simplify userspace governor") which incorrectly assumed that
policy->cur == user requested frequency via scaling_setspeed. This won't
be true if the user requested frequency falls outside policy->{min/max}.
Ex: a temporary thermal cap throttled the user requested frequency.

Fix this by storing the user requested frequency in a seperate variable.
The governor will then try to achieve this request on every GOV_LIMITS
change.

Fixes: d1922f02562f (cpufreq: Simplify userspace governor)
Signed-off-by: Sai Gurrappadi <sgurrappadi@nvidia.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
intel_pstate: Fix MSR_CONFIG_TDP_x addressing in core_get_max_pstate() 2016-08-20T16:09:18+00:00 Jan Kiszka jan.kiszka@siemens.com 2016-07-08T18:42:04+00:00 695c69bf304d7874e0b918684818711f0d7830f9 commit 5fc8f707a2aa40c767c3a338738b9b6fcd151ac1 upstream. If MSR_CONFIG_TDP_CONTROL is locked, we currently try to address some MSR 0x80000648 or so. Mask out the relevant level bits 0 and 1. Found while running over the Jailhouse hypervisor which became upset about this strange MSR index. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 5fc8f707a2aa40c767c3a338738b9b6fcd151ac1 upstream.

If MSR_CONFIG_TDP_CONTROL is locked, we currently try to address some
MSR 0x80000648 or so. Mask out the relevant level bits 0 and 1.

Found while running over the Jailhouse hypervisor which became upset
about this strange MSR index.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cpufreq: intel_pstate: Fix processing for turbo activation ratio 2016-05-04T21:48:44+00:00 Srinivas Pandruvada srinivas.pandruvada@linux.intel.com 2016-04-23T02:53:59+00:00 61fe67520c4394c90f688c61c5c16dd63824cd42 commit 1becf03545a0859ceaaf9e8c2d9861882a71cb01 upstream. When the config TDP level is not nominal (level = 0), the MSR values for reading level 1 and level 2 ratios contain power in low 14 bits and actual ratio bits are at bits [23:16]. The current processing for level 1 and level 2 is wrong as there is no shift done to get actual ratio. Fixes: 6a35fc2d6c22 (cpufreq: intel_pstate: get P1 from TAR when available) Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 1becf03545a0859ceaaf9e8c2d9861882a71cb01 upstream.

When the config TDP level is not nominal (level = 0), the MSR values for
reading level 1 and level 2 ratios contain power in low 14 bits and actual
ratio bits are at bits [23:16]. The current processing for level 1 and
level 2 is wrong as there is no shift done to get actual ratio.

Fixes: 6a35fc2d6c22 (cpufreq: intel_pstate: get P1 from TAR when available)
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cpufreq: Fix NULL reference crash while accessing policy->governor_data 2016-03-03T23:07:25+00:00 Viresh Kumar viresh.kumar@linaro.org 2016-01-25T17:03:46+00:00 0ac4a2a8bae9838d69be6dec3212e3630fb5773c commit e4b133cc4b30b48d488e4e4fffb132f173ce4358 upstream. There is a race discovered by Juri, where we are able to: - create and read a sysfs file before policy->governor_data is being set to a non NULL value. OR - set policy->governor_data to NULL, and reading a file before being destroyed. And so such a crash is reported: Unable to handle kernel NULL pointer dereference at virtual address 0000000c pgd = edfc8000 [0000000c] *pgd=bfc8c835 Internal error: Oops: 17 [#1] SMP ARM Modules linked in: CPU: 4 PID: 1730 Comm: cat Not tainted 4.5.0-rc1+ #463 Hardware name: ARM-Versatile Express task: ee8e8480 ti: ee930000 task.ti: ee930000 PC is at show_ignore_nice_load_gov_pol+0x24/0x34 LR is at show+0x4c/0x60 pc : [<c058f1bc>] lr : [<c058ae88>] psr: a0070013 sp : ee931dd0 ip : ee931de0 fp : ee931ddc r10: ee4bc290 r9 : 00001000 r8 : ef2cb000 r7 : ee4bc200 r6 : ef2cb000 r5 : c0af57b0 r4 : ee4bc2e0 r3 : 00000000 r2 : 00000000 r1 : c0928df4 r0 : ef2cb000 Flags: NzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 10c5387d Table: adfc806a DAC: 00000051 Process cat (pid: 1730, stack limit = 0xee930210) Stack: (0xee931dd0 to 0xee932000) 1dc0: ee931dfc ee931de0 c058ae88 c058f1a4 1de0: edce3bc0 c07bfca4 edce3ac0 00001000 ee931e24 ee931e00 c01fcb90 c058ae48 1e00: 00000001 edce3bc0 00000000 00000001 ee931e50 ee8ff480 ee931e34 ee931e28 1e20: c01fb33c c01fcb0c ee931e8c ee931e38 c01a5210 c01fb314 ee931e9c ee931e48 1e40: 00000000 edce3bf0 befe4a00 ee931f78 00000000 00000000 000001e4 00000000 1e60: c00545a8 edce3ac0 00001000 00001000 befe4a00 ee931f78 00000000 00001000 1e80: ee931ed4 ee931e90 c01fbed8 c01a5038 ed085a58 00020000 00000000 00000000 1ea0: c0ad72e4 ee931f78 ee8ff488 ee8ff480 c077f3fc 00001000 befe4a00 ee931f78 1ec0: 00000000 00001000 ee931f44 ee931ed8 c017c328 c01fbdc4 00001000 00000000 1ee0: ee8ff480 00001000 ee931f44 ee931ef8 c017c65c c03deb10 ee931fac ee931f08 1f00: c0009270 c001f290 c0a8d968 ef2cb000 ef2cb000 ee8ff480 00000020 ee8ff480 1f20: ee8ff480 befe4a00 00001000 ee931f78 00000000 00000000 ee931f74 ee931f48 1f40: c017d1ec c017c2f8 c019c724 c019c684 ee8ff480 ee8ff480 00001000 befe4a00 1f60: 00000000 00000000 ee931fa4 ee931f78 c017d2a8 c017d160 00000000 00000000 1f80: 000a9f20 00001000 befe4a00 00000003 c000ffe4 ee930000 00000000 ee931fa8 1fa0: c000fe40 c017d264 000a9f20 00001000 00000003 befe4a00 00001000 00000000 Unable to handle kernel NULL pointer dereference at virtual address 0000000c 1fc0: 000a9f20 00001000 befe4a00 00000003 00000000 00000000 00000003 00000001 pgd = edfc4000 [0000000c] *pgd=bfcac835 1fe0: 00000000 befe49dc 000197f8 b6e35dfc 60070010 00000003 3065b49d 134ac2c9 [<c058f1bc>] (show_ignore_nice_load_gov_pol) from [<c058ae88>] (show+0x4c/0x60) [<c058ae88>] (show) from [<c01fcb90>] (sysfs_kf_seq_show+0x90/0xfc) [<c01fcb90>] (sysfs_kf_seq_show) from [<c01fb33c>] (kernfs_seq_show+0x34/0x38) [<c01fb33c>] (kernfs_seq_show) from [<c01a5210>] (seq_read+0x1e4/0x4e4) [<c01a5210>] (seq_read) from [<c01fbed8>] (kernfs_fop_read+0x120/0x1a0) [<c01fbed8>] (kernfs_fop_read) from [<c017c328>] (__vfs_read+0x3c/0xe0) [<c017c328>] (__vfs_read) from [<c017d1ec>] (vfs_read+0x98/0x104) [<c017d1ec>] (vfs_read) from [<c017d2a8>] (SyS_read+0x50/0x90) [<c017d2a8>] (SyS_read) from [<c000fe40>] (ret_fast_syscall+0x0/0x1c) Code: e5903044 e1a00001 e3081df4 e34c1092 (e593300c) ---[ end trace 5994b9a5111f35ee ]--- Fix that by making sure, policy->governor_data is updated at the right places only. Reported-and-tested-by: Juri Lelli <juri.lelli@arm.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit e4b133cc4b30b48d488e4e4fffb132f173ce4358 upstream.

There is a race discovered by Juri, where we are able to:
- create and read a sysfs file before policy->governor_data is being set
  to a non NULL value.
  OR
- set policy->governor_data to NULL, and reading a file before being
  destroyed.

And so such a crash is reported:

Unable to handle kernel NULL pointer dereference at virtual address 0000000c
pgd = edfc8000
[0000000c] *pgd=bfc8c835
Internal error: Oops: 17 [#1] SMP ARM
Modules linked in:
CPU: 4 PID: 1730 Comm: cat Not tainted 4.5.0-rc1+ #463
Hardware name: ARM-Versatile Express
task: ee8e8480 ti: ee930000 task.ti: ee930000
PC is at show_ignore_nice_load_gov_pol+0x24/0x34
LR is at show+0x4c/0x60
pc : [<c058f1bc>]    lr : [<c058ae88>]    psr: a0070013
sp : ee931dd0  ip : ee931de0  fp : ee931ddc
r10: ee4bc290  r9 : 00001000  r8 : ef2cb000
r7 : ee4bc200  r6 : ef2cb000  r5 : c0af57b0  r4 : ee4bc2e0
r3 : 00000000  r2 : 00000000  r1 : c0928df4  r0 : ef2cb000
Flags: NzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
Control: 10c5387d  Table: adfc806a  DAC: 00000051
Process cat (pid: 1730, stack limit = 0xee930210)
Stack: (0xee931dd0 to 0xee932000)
1dc0:                                     ee931dfc ee931de0 c058ae88 c058f1a4
1de0: edce3bc0 c07bfca4 edce3ac0 00001000 ee931e24 ee931e00 c01fcb90 c058ae48
1e00: 00000001 edce3bc0 00000000 00000001 ee931e50 ee8ff480 ee931e34 ee931e28
1e20: c01fb33c c01fcb0c ee931e8c ee931e38 c01a5210 c01fb314 ee931e9c ee931e48
1e40: 00000000 edce3bf0 befe4a00 ee931f78 00000000 00000000 000001e4 00000000
1e60: c00545a8 edce3ac0 00001000 00001000 befe4a00 ee931f78 00000000 00001000
1e80: ee931ed4 ee931e90 c01fbed8 c01a5038 ed085a58 00020000 00000000 00000000
1ea0: c0ad72e4 ee931f78 ee8ff488 ee8ff480 c077f3fc 00001000 befe4a00 ee931f78
1ec0: 00000000 00001000 ee931f44 ee931ed8 c017c328 c01fbdc4 00001000 00000000
1ee0: ee8ff480 00001000 ee931f44 ee931ef8 c017c65c c03deb10 ee931fac ee931f08
1f00: c0009270 c001f290 c0a8d968 ef2cb000 ef2cb000 ee8ff480 00000020 ee8ff480
1f20: ee8ff480 befe4a00 00001000 ee931f78 00000000 00000000 ee931f74 ee931f48
1f40: c017d1ec c017c2f8 c019c724 c019c684 ee8ff480 ee8ff480 00001000 befe4a00
1f60: 00000000 00000000 ee931fa4 ee931f78 c017d2a8 c017d160 00000000 00000000
1f80: 000a9f20 00001000 befe4a00 00000003 c000ffe4 ee930000 00000000 ee931fa8
1fa0: c000fe40 c017d264 000a9f20 00001000 00000003 befe4a00 00001000 00000000
Unable to handle kernel NULL pointer dereference at virtual address 0000000c
1fc0: 000a9f20 00001000 befe4a00 00000003 00000000 00000000 00000003 00000001
pgd = edfc4000
[0000000c] *pgd=bfcac835
1fe0: 00000000 befe49dc 000197f8 b6e35dfc 60070010 00000003 3065b49d 134ac2c9

[<c058f1bc>] (show_ignore_nice_load_gov_pol) from [<c058ae88>] (show+0x4c/0x60)
[<c058ae88>] (show) from [<c01fcb90>] (sysfs_kf_seq_show+0x90/0xfc)
[<c01fcb90>] (sysfs_kf_seq_show) from [<c01fb33c>] (kernfs_seq_show+0x34/0x38)
[<c01fb33c>] (kernfs_seq_show) from [<c01a5210>] (seq_read+0x1e4/0x4e4)
[<c01a5210>] (seq_read) from [<c01fbed8>] (kernfs_fop_read+0x120/0x1a0)
[<c01fbed8>] (kernfs_fop_read) from [<c017c328>] (__vfs_read+0x3c/0xe0)
[<c017c328>] (__vfs_read) from [<c017d1ec>] (vfs_read+0x98/0x104)
[<c017d1ec>] (vfs_read) from [<c017d2a8>] (SyS_read+0x50/0x90)
[<c017d2a8>] (SyS_read) from [<c000fe40>] (ret_fast_syscall+0x0/0x1c)
Code: e5903044 e1a00001 e3081df4 e34c1092 (e593300c)
---[ end trace 5994b9a5111f35ee ]---

Fix that by making sure, policy->governor_data is updated at the right
places only.

Reported-and-tested-by: Juri Lelli <juri.lelli@arm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cpufreq: pxa2xx: fix pxa_cpufreq_change_voltage prototype 2016-03-03T23:07:25+00:00 Arnd Bergmann arnd@arndb.de 2016-01-25T15:44:38+00:00 286ab25d69068cef7c97e305af347288b9f1ab4a commit fb2a24a1c6457d21df9fae0dd66b20c63ba56077 upstream. There are two definitions of pxa_cpufreq_change_voltage, with slightly different prototypes after one of them had its argument marked 'const'. Now the other one (for !CONFIG_REGULATOR) produces a harmless warning: drivers/cpufreq/pxa2xx-cpufreq.c: In function 'pxa_set_target': drivers/cpufreq/pxa2xx-cpufreq.c:291:36: warning: passing argument 1 of 'pxa_cpufreq_change_voltage' discards 'const' qualifier from pointer target type [-Wdiscarded-qualifiers] ret = pxa_cpufreq_change_voltage(&pxa_freq_settings[idx]); ^ drivers/cpufreq/pxa2xx-cpufreq.c:205:12: note: expected 'struct pxa_freqs *' but argument is of type 'const struct pxa_freqs *' static int pxa_cpufreq_change_voltage(struct pxa_freqs *pxa_freq) ^ This changes the prototype in the same way as the other, which avoids the warning. Fixes: 03c229906311 (cpufreq: pxa: make pxa_freqs arrays const) Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit fb2a24a1c6457d21df9fae0dd66b20c63ba56077 upstream.

There are two definitions of pxa_cpufreq_change_voltage, with slightly
different prototypes after one of them had its argument marked 'const'.
Now the other one (for !CONFIG_REGULATOR) produces a harmless warning:

drivers/cpufreq/pxa2xx-cpufreq.c: In function 'pxa_set_target':
drivers/cpufreq/pxa2xx-cpufreq.c:291:36: warning: passing argument 1 of 'pxa_cpufreq_change_voltage' discards 'const' qualifier from pointer target type [-Wdiscarded-qualifiers]
   ret = pxa_cpufreq_change_voltage(&pxa_freq_settings[idx]);
                                    ^
drivers/cpufreq/pxa2xx-cpufreq.c:205:12: note: expected 'struct pxa_freqs *' but argument is of type 'const struct pxa_freqs *'
 static int pxa_cpufreq_change_voltage(struct pxa_freqs *pxa_freq)
            ^

This changes the prototype in the same way as the other, which
avoids the warning.

Fixes: 03c229906311 (cpufreq: pxa: make pxa_freqs arrays const)
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>