* SMP local timers and their CPUfreq notifiers setup on OMAP3 [not found] <8739aahc0n.fsf@ti.com> @ 2012-02-17 7:48 ` Santosh Shilimkar 2012-02-17 9:47 ` Marc Zyngier 0 siblings, 1 reply; 11+ messages in thread From: Santosh Shilimkar @ 2012-02-17 7:48 UTC (permalink / raw) To: linux-arm-kernel (+ linux-arm, Marc) On Thursday 16 February 2012 11:54 PM, Kevin Hilman wrote: > Hi Santosh, > > Using v3.3-rc3 and building an OMAP2+ kernel I noticed that CPUfreq > transitions fault because of the TWD cpufreq notifiers being called even > on OMAP3. > > Of course, the TWD doesn't exist on OMAP3, but the TWD init is still > setting up notifiers. I tried just adding a !cpu_is_omap44xx() check > in local_timer_setup(), but that didn't do it, so there's more timer > init that needs to be fixed up. Can you have a look at this? > > It's easy to reproduce by just manually triggering a frequency change > with the userspace governor. Here's what I did on my 3430/n900: > Below patch fixes the issue. Regards Santosh >From 3a16f7a6694c14e201fdf6ad195c821816b2de84 Mon Sep 17 00:00:00 2001 From: Santosh Shilimkar <santosh.shilimkar@ti.com> Date: Fri, 17 Feb 2012 11:11:28 +0530 Subject: [PATCH] ARM: smp_twd: Don't register CPUFREQ notifiers if local timers are not initialised. Current ARM local timer code registers CPUFREQ notifiers even in case the twd_timer_setup() isn't called. That seems to be wrong and would eventually lead to kernel crash on the CPU frequency transitions on the SOCs where the local timer doesn't exist or broken because of hardware BUG. Fix it by uisng an initialised variable. Though the twd_timer_setup() is percpu, the idea here is to avoid the CPUFREQ registration. Hence percpu initialised variable is not used. The issue was observed with v3.3-rc3 and building an OMAP2+ kernel on OMAP3 SOC which doesn't have TWD. Below is the dump for reference : Unable to handle kernel paging request at virtual address 007e900 pgd = cdc20000 [007e9000] *pgd=00000000 Internal error: Oops: 5 [#1] SMP Modules linked in: CPU: 0 Not tainted (3.3.0-rc3-pm+debug+initramfs #9) PC is at twd_update_frequency+0x34/0x48 LR is at twd_update_frequency+0x10/0x48 pc : [<c001382c>] lr : [<c0013808>] psr: 60000093 sp : ce311dd8 ip : 00000000 fp : 00000000 r10: 00000000 r9 : 00000001 r8 : ce310000 r7 : c0440458 r6 : c00137f8 r5 : 00000000 r4 : c0947a74 r3 : 00000000 r2 : 007e9000 r1 : 00000000 r0 : 00000000 Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment usr Control: 10c5387d Table: 8dc20019 DAC: 00000015 Process sh (pid: 599, stack limit = 0xce3102f8) Stack: (0xce311dd8 to 0xce312000) 1dc0: 6000c 1de0: 00000001 00000002 00000000 00000000 00000000 00000000 00000 1e00: ffffffff c093d8f0 00000000 ce311ebc 00000001 00000001 ce310 1e20: c001386c c0437c4c c0e95b60 c0e95ba8 00000001 c0e95bf8 ffff4 1e40: 00000000 00000000 c005ef74 ce310000 c0435cf0 ce311ebc 00000 1e60: ce352b40 0007a120 c08d5108 c08ba040 c08ba040 c005f030 00000 1e80: c08bc554 c032fe2c 0007a120 c08d4b64 ce352b40 c08d8618 ffff8 1ea0: c08ba040 c033364c ce311ecc c0433b50 00000002 ffffffea c0330 1ec0: 0007a120 0007a120 22222201 00000000 22222222 00000000 ce357 1ee0: ce3d6000 cdc2aed8 ce352ba0 c0470164 00000002 c032f47c 00034 1f00: c0331cac ce352b40 00000007 c032f6d0 ce352bbc 0003d090 c0930 1f20: c093d8bc c03306a4 00000007 ce311f80 00000007 cdc2aec0 ce358 1f40: ce8d20c0 00000007 b6fe5000 ce311f80 00000007 ce310000 0000c 1f60: c000de74 ce987400 ce8d20c0 b6fe5000 00000000 00000000 0000c 1f80: 00000000 00000000 001fbac8 00000000 00000007 001fbac8 00004 1fa0: c000df04 c000dd60 00000007 001fbac8 00000001 b6fe5000 00000 1fc0: 00000007 001fbac8 00000007 00000004 b6fe5000 00000000 00202 1fe0: 00000000 beb565f8 00101ffc 00008e8c 60000010 00000001 00000 [<c001382c>] (twd_update_frequency+0x34/0x48) from [<c008ac4c>] ) [<c008ac4c>] (smp_call_function_single+0x17c/0x1c8) from [<c0013) [<c0013890>] (twd_cpufreq_transition+0x24/0x30) from [<c0437c4c>) [<c0437c4c>] (notifier_call_chain+0x44/0x84) from [<c005efe4>] () [<c005efe4>] (__srcu_notifier_call_chain+0x70/0xa4) from [<c005f) [<c005f030>] (srcu_notifier_call_chain+0x18/0x20) from [<c032fe2) [<c032fe2c>] (cpufreq_notify_transition+0xc8/0x1b0) from [<c0333) [<c033364c>] (omap_target+0x1b4/0x28c) from [<c032f47c>] (__cpuf) [<c032f47c>] (__cpufreq_driver_target+0x50/0x64) from [<c0331d24) [<c0331d24>] (cpufreq_set+0x78/0x98) from [<c032f6d0>] (store_sc) [<c032f6d0>] (store_scaling_setspeed+0x5c/0x74) from [<c03306a4>) [<c03306a4>] (store+0x58/0x74) from [<c014d868>] (sysfs_write_fi) [<c014d868>] (sysfs_write_file+0x80/0xb4) from [<c00f2c2c>] (vfs) [<c00f2c2c>] (vfs_write+0xa8/0x138) from [<c00f2e9c>] (sys_write) [<c00f2e9c>] (sys_write+0x40/0x6c) from [<c000dd60>] (ret_fast_s) Code: e594300c e792210c e1a01000 e5840004 (e7930002) ---[ end trace 5da3b5167c1ecdda ]--- Reported-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> --- arch/arm/kernel/smp_twd.c | 4 +++- 1 files changed, 3 insertions(+), 1 deletions(-) diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c index 4285daa..753ae37 100644 --- a/arch/arm/kernel/smp_twd.c +++ b/arch/arm/kernel/smp_twd.c @@ -30,6 +30,7 @@ void __iomem *twd_base; static struct clk *twd_clk; static unsigned long twd_timer_rate; +static bool twd_initialised; static struct clock_event_device __percpu **twd_evt; @@ -129,7 +130,7 @@ static struct notifier_block twd_cpufreq_nb = { static int twd_cpufreq_init(void) { - if (!IS_ERR(twd_clk)) + if ((!IS_ERR(twd_clk)) && twd_initialised) return cpufreq_register_notifier(&twd_cpufreq_nb, CPUFREQ_TRANSITION_NOTIFIER); @@ -267,4 +268,5 @@ void __cpuinit twd_timer_setup(struct clock_event_device *clk) clockevents_config_and_register(clk, twd_timer_rate, 0xf, 0xffffffff); enable_percpu_irq(clk->irq, 0); + twd_initialised = 1; } -- 1.7.4.1 -------------- next part -------------- A non-text attachment was scrubbed... Name: 0001-ARM-smp_twd-Don-t-register-CPUFREQ-notifiers-if-loca.patch Type: text/x-patch Size: 5006 bytes Desc: not available URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20120217/9c7cf781/attachment-0001.bin> ^ permalink raw reply related [flat|nested] 11+ messages in thread
* SMP local timers and their CPUfreq notifiers setup on OMAP3 2012-02-17 7:48 ` SMP local timers and their CPUfreq notifiers setup on OMAP3 Santosh Shilimkar @ 2012-02-17 9:47 ` Marc Zyngier 2012-02-17 10:40 ` Shilimkar, Santosh 0 siblings, 1 reply; 11+ messages in thread From: Marc Zyngier @ 2012-02-17 9:47 UTC (permalink / raw) To: linux-arm-kernel Hi Santosh, On Fri, 17 Feb 2012 13:18:37 +0530, Santosh Shilimkar <santosh.shilimkar@ti.com> wrote: > > From 3a16f7a6694c14e201fdf6ad195c821816b2de84 Mon Sep 17 00:00:00 2001 > From: Santosh Shilimkar <santosh.shilimkar@ti.com> > Date: Fri, 17 Feb 2012 11:11:28 +0530 > Subject: [PATCH] ARM: smp_twd: Don't register CPUFREQ notifiers if local > timers are not initialised. > > Current ARM local timer code registers CPUFREQ notifiers even in case > the twd_timer_setup() isn't called. That seems to be wrong and > would eventually lead to kernel crash on the CPU frequency transitions > on the SOCs where the local timer doesn't exist or broken because of > hardware BUG. > > Fix it by uisng an initialised variable. Though the twd_timer_setup() > is percpu, the idea here is to avoid the CPUFREQ registration. Hence > percpu initialised variable is not used. > > The issue was observed with v3.3-rc3 and building an OMAP2+ kernel > on OMAP3 SOC which doesn't have TWD. > > Below is the dump for reference : > > Unable to handle kernel paging request at virtual address 007e900 > pgd = cdc20000 > [007e9000] *pgd=00000000 > Internal error: Oops: 5 [#1] SMP > Modules linked in: > CPU: 0 Not tainted (3.3.0-rc3-pm+debug+initramfs #9) > PC is at twd_update_frequency+0x34/0x48 > LR is at twd_update_frequency+0x10/0x48 > pc : [<c001382c>] lr : [<c0013808>] psr: 60000093 > sp : ce311dd8 ip : 00000000 fp : 00000000 > r10: 00000000 r9 : 00000001 r8 : ce310000 > r7 : c0440458 r6 : c00137f8 r5 : 00000000 r4 : c0947a74 > r3 : 00000000 r2 : 007e9000 r1 : 00000000 r0 : 00000000 > Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment usr > Control: 10c5387d Table: 8dc20019 DAC: 00000015 > Process sh (pid: 599, stack limit = 0xce3102f8) > Stack: (0xce311dd8 to 0xce312000) > 1dc0: 6000c > 1de0: 00000001 00000002 00000000 00000000 00000000 00000000 00000 > 1e00: ffffffff c093d8f0 00000000 ce311ebc 00000001 00000001 ce310 > 1e20: c001386c c0437c4c c0e95b60 c0e95ba8 00000001 c0e95bf8 ffff4 > 1e40: 00000000 00000000 c005ef74 ce310000 c0435cf0 ce311ebc 00000 > 1e60: ce352b40 0007a120 c08d5108 c08ba040 c08ba040 c005f030 00000 > 1e80: c08bc554 c032fe2c 0007a120 c08d4b64 ce352b40 c08d8618 ffff8 > 1ea0: c08ba040 c033364c ce311ecc c0433b50 00000002 ffffffea c0330 > 1ec0: 0007a120 0007a120 22222201 00000000 22222222 00000000 ce357 > 1ee0: ce3d6000 cdc2aed8 ce352ba0 c0470164 00000002 c032f47c 00034 > 1f00: c0331cac ce352b40 00000007 c032f6d0 ce352bbc 0003d090 c0930 > 1f20: c093d8bc c03306a4 00000007 ce311f80 00000007 cdc2aec0 ce358 > 1f40: ce8d20c0 00000007 b6fe5000 ce311f80 00000007 ce310000 0000c > 1f60: c000de74 ce987400 ce8d20c0 b6fe5000 00000000 00000000 0000c > 1f80: 00000000 00000000 001fbac8 00000000 00000007 001fbac8 00004 > 1fa0: c000df04 c000dd60 00000007 001fbac8 00000001 b6fe5000 00000 > 1fc0: 00000007 001fbac8 00000007 00000004 b6fe5000 00000000 00202 > 1fe0: 00000000 beb565f8 00101ffc 00008e8c 60000010 00000001 00000 > [<c001382c>] (twd_update_frequency+0x34/0x48) from [<c008ac4c>] ) > [<c008ac4c>] (smp_call_function_single+0x17c/0x1c8) from [<c0013) > [<c0013890>] (twd_cpufreq_transition+0x24/0x30) from [<c0437c4c>) > [<c0437c4c>] (notifier_call_chain+0x44/0x84) from [<c005efe4>] () > [<c005efe4>] (__srcu_notifier_call_chain+0x70/0xa4) from [<c005f) > [<c005f030>] (srcu_notifier_call_chain+0x18/0x20) from [<c032fe2) > [<c032fe2c>] (cpufreq_notify_transition+0xc8/0x1b0) from [<c0333) > [<c033364c>] (omap_target+0x1b4/0x28c) from [<c032f47c>] (__cpuf) > [<c032f47c>] (__cpufreq_driver_target+0x50/0x64) from [<c0331d24) > [<c0331d24>] (cpufreq_set+0x78/0x98) from [<c032f6d0>] (store_sc) > [<c032f6d0>] (store_scaling_setspeed+0x5c/0x74) from [<c03306a4>) > [<c03306a4>] (store+0x58/0x74) from [<c014d868>] (sysfs_write_fi) > [<c014d868>] (sysfs_write_file+0x80/0xb4) from [<c00f2c2c>] (vfs) > [<c00f2c2c>] (vfs_write+0xa8/0x138) from [<c00f2e9c>] (sys_write) > [<c00f2e9c>] (sys_write+0x40/0x6c) from [<c000dd60>] (ret_fast_s) > Code: e594300c e792210c e1a01000 e5840004 (e7930002) > ---[ end trace 5da3b5167c1ecdda ]--- > > Reported-by: Kevin Hilman <khilman@ti.com> > Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> > --- > arch/arm/kernel/smp_twd.c | 4 +++- > 1 files changed, 3 insertions(+), 1 deletions(-) > > diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c > index 4285daa..753ae37 100644 > --- a/arch/arm/kernel/smp_twd.c > +++ b/arch/arm/kernel/smp_twd.c > @@ -30,6 +30,7 @@ void __iomem *twd_base; > > static struct clk *twd_clk; > static unsigned long twd_timer_rate; > +static bool twd_initialised; > > static struct clock_event_device __percpu **twd_evt; > > @@ -129,7 +130,7 @@ static struct notifier_block twd_cpufreq_nb = { > > static int twd_cpufreq_init(void) > { > - if (!IS_ERR(twd_clk)) > + if ((!IS_ERR(twd_clk)) && twd_initialised) > return cpufreq_register_notifier(&twd_cpufreq_nb, > CPUFREQ_TRANSITION_NOTIFIER); Testing twd_evt and *__this_cpu_ptr(twd_evt) should have a similar effect, and save the additional variable. M. -- Fast, cheap, reliable. Pick two. ^ permalink raw reply [flat|nested] 11+ messages in thread
* SMP local timers and their CPUfreq notifiers setup on OMAP3 2012-02-17 9:47 ` Marc Zyngier @ 2012-02-17 10:40 ` Shilimkar, Santosh 2012-02-17 10:47 ` Russell King - ARM Linux 2012-02-17 11:06 ` Marc Zyngier 0 siblings, 2 replies; 11+ messages in thread From: Shilimkar, Santosh @ 2012-02-17 10:40 UTC (permalink / raw) To: linux-arm-kernel On Fri, Feb 17, 2012 at 3:17 PM, Marc Zyngier <marc.zyngier@arm.com> wrote: > > Hi Santosh, > > On Fri, 17 Feb 2012 13:18:37 +0530, Santosh Shilimkar > <santosh.shilimkar@ti.com> wrote: >> [...] >> ?arch/arm/kernel/smp_twd.c | ? ?4 +++- >> ?1 files changed, 3 insertions(+), 1 deletions(-) >> >> diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c >> index 4285daa..753ae37 100644 >> --- a/arch/arm/kernel/smp_twd.c >> +++ b/arch/arm/kernel/smp_twd.c >> @@ -30,6 +30,7 @@ void __iomem *twd_base; >> >> ?static struct clk *twd_clk; >> ?static unsigned long twd_timer_rate; >> +static bool twd_initialised; >> >> ?static struct clock_event_device __percpu **twd_evt; >> >> @@ -129,7 +130,7 @@ static struct notifier_block twd_cpufreq_nb = { >> >> ?static int twd_cpufreq_init(void) >> ?{ >> - ? ? if (!IS_ERR(twd_clk)) >> + ? ? if ((!IS_ERR(twd_clk)) && twd_initialised) >> ? ? ? ? ? ? ? return cpufreq_register_notifier(&twd_cpufreq_nb, >> ? ? ? ? ? ? ? ? ? ? ? CPUFREQ_TRANSITION_NOTIFIER); > > Testing twd_evt and *__this_cpu_ptr(twd_evt) should have a similar effect, > and save the additional variable. > Indeed. Updated patch below. >From 4d351f59e5dabe065d51304455ee01b191cb56d6 Mon Sep 17 00:00:00 2001 From: Santosh Shilimkar <santosh.shilimkar@ti.com> Date: Fri, 17 Feb 2012 11:11:28 +0530 Subject: [PATCH] ARM: smp_twd: Don't register CPUFREQ notifiers if local timers are not initialised. Current ARM local timer code registers CPUFREQ notifiers even in case the twd_timer_setup() isn't called. That seems to be wrong and would eventually lead to kernel crash on the CPU frequency transitions on the SOCs where the local timer doesn't exist or broken because of hardware BUG. Fix it by testing twd_evt and *__this_cpu_ptr(twd_evt). The issue was observed with v3.3-rc3 and building an OMAP2+ kernel on OMAP3 SOC which doesn't have TWD. Below is the dump for reference : Unable to handle kernel paging request at virtual address 007e900 pgd = cdc20000 [007e9000] *pgd=00000000 Internal error: Oops: 5 [#1] SMP Modules linked in: CPU: 0 Not tainted (3.3.0-rc3-pm+debug+initramfs #9) PC is at twd_update_frequency+0x34/0x48 LR is at twd_update_frequency+0x10/0x48 pc : [<c001382c>] lr : [<c0013808>] psr: 60000093 sp : ce311dd8 ip : 00000000 fp : 00000000 r10: 00000000 r9 : 00000001 r8 : ce310000 r7 : c0440458 r6 : c00137f8 r5 : 00000000 r4 : c0947a74 r3 : 00000000 r2 : 007e9000 r1 : 00000000 r0 : 00000000 Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment usr Control: 10c5387d Table: 8dc20019 DAC: 00000015 Process sh (pid: 599, stack limit = 0xce3102f8) Stack: (0xce311dd8 to 0xce312000) 1dc0: 6000c 1de0: 00000001 00000002 00000000 00000000 00000000 00000000 00000 1e00: ffffffff c093d8f0 00000000 ce311ebc 00000001 00000001 ce310 1e20: c001386c c0437c4c c0e95b60 c0e95ba8 00000001 c0e95bf8 ffff4 1e40: 00000000 00000000 c005ef74 ce310000 c0435cf0 ce311ebc 00000 1e60: ce352b40 0007a120 c08d5108 c08ba040 c08ba040 c005f030 00000 1e80: c08bc554 c032fe2c 0007a120 c08d4b64 ce352b40 c08d8618 ffff8 1ea0: c08ba040 c033364c ce311ecc c0433b50 00000002 ffffffea c0330 1ec0: 0007a120 0007a120 22222201 00000000 22222222 00000000 ce357 1ee0: ce3d6000 cdc2aed8 ce352ba0 c0470164 00000002 c032f47c 00034 1f00: c0331cac ce352b40 00000007 c032f6d0 ce352bbc 0003d090 c0930 1f20: c093d8bc c03306a4 00000007 ce311f80 00000007 cdc2aec0 ce358 1f40: ce8d20c0 00000007 b6fe5000 ce311f80 00000007 ce310000 0000c 1f60: c000de74 ce987400 ce8d20c0 b6fe5000 00000000 00000000 0000c 1f80: 00000000 00000000 001fbac8 00000000 00000007 001fbac8 00004 1fa0: c000df04 c000dd60 00000007 001fbac8 00000001 b6fe5000 00000 1fc0: 00000007 001fbac8 00000007 00000004 b6fe5000 00000000 00202 1fe0: 00000000 beb565f8 00101ffc 00008e8c 60000010 00000001 00000 [<c001382c>] (twd_update_frequency+0x34/0x48) from [<c008ac4c>] ) [<c008ac4c>] (smp_call_function_single+0x17c/0x1c8) from [<c0013) [<c0013890>] (twd_cpufreq_transition+0x24/0x30) from [<c0437c4c>) [<c0437c4c>] (notifier_call_chain+0x44/0x84) from [<c005efe4>] () [<c005efe4>] (__srcu_notifier_call_chain+0x70/0xa4) from [<c005f) [<c005f030>] (srcu_notifier_call_chain+0x18/0x20) from [<c032fe2) [<c032fe2c>] (cpufreq_notify_transition+0xc8/0x1b0) from [<c0333) [<c033364c>] (omap_target+0x1b4/0x28c) from [<c032f47c>] (__cpuf) [<c032f47c>] (__cpufreq_driver_target+0x50/0x64) from [<c0331d24) [<c0331d24>] (cpufreq_set+0x78/0x98) from [<c032f6d0>] (store_sc) [<c032f6d0>] (store_scaling_setspeed+0x5c/0x74) from [<c03306a4>) [<c03306a4>] (store+0x58/0x74) from [<c014d868>] (sysfs_write_fi) [<c014d868>] (sysfs_write_file+0x80/0xb4) from [<c00f2c2c>] (vfs) [<c00f2c2c>] (vfs_write+0xa8/0x138) from [<c00f2e9c>] (sys_write) [<c00f2e9c>] (sys_write+0x40/0x6c) from [<c000dd60>] (ret_fast_s) Code: e594300c e792210c e1a01000 e5840004 (e7930002) ---[ end trace 5da3b5167c1ecdda ]--- Reported-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> --- arch/arm/kernel/smp_twd.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c index 4285daa..265a18a 100644 --- a/arch/arm/kernel/smp_twd.c +++ b/arch/arm/kernel/smp_twd.c @@ -129,7 +129,7 @@ static struct notifier_block twd_cpufreq_nb = { static int twd_cpufreq_init(void) { - if (!IS_ERR(twd_clk)) + if ((!twd_evt) && (!__this_cpu_ptr(twd_evt)) && (!IS_ERR(twd_clk))) return cpufreq_register_notifier(&twd_cpufreq_nb, CPUFREQ_TRANSITION_NOTIFIER); -- 1.7.4.1 -------------- next part -------------- A non-text attachment was scrubbed... Name: 0001-ARM-smp_twd-Don-t-register-CPUFREQ-notifiers-if-loca.patch Type: application/octet-stream Size: 4482 bytes Desc: not available URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20120217/1f86683b/attachment-0001.obj> ^ permalink raw reply related [flat|nested] 11+ messages in thread
* SMP local timers and their CPUfreq notifiers setup on OMAP3 2012-02-17 10:40 ` Shilimkar, Santosh @ 2012-02-17 10:47 ` Russell King - ARM Linux 2012-02-17 11:06 ` Marc Zyngier 1 sibling, 0 replies; 11+ messages in thread From: Russell King - ARM Linux @ 2012-02-17 10:47 UTC (permalink / raw) To: linux-arm-kernel On Fri, Feb 17, 2012 at 04:10:57PM +0530, Shilimkar, Santosh wrote: > - if (!IS_ERR(twd_clk)) > + if ((!twd_evt) && (!__this_cpu_ptr(twd_evt)) && (!IS_ERR(twd_clk))) Too many parens. ^ permalink raw reply [flat|nested] 11+ messages in thread
* SMP local timers and their CPUfreq notifiers setup on OMAP3 2012-02-17 10:40 ` Shilimkar, Santosh 2012-02-17 10:47 ` Russell King - ARM Linux @ 2012-02-17 11:06 ` Marc Zyngier 2012-02-17 12:28 ` Santosh Shilimkar 1 sibling, 1 reply; 11+ messages in thread From: Marc Zyngier @ 2012-02-17 11:06 UTC (permalink / raw) To: linux-arm-kernel On 17/02/12 10:40, Shilimkar, Santosh wrote: > On Fri, Feb 17, 2012 at 3:17 PM, Marc Zyngier <marc.zyngier@arm.com> wrote: >> >> Hi Santosh, >> >> On Fri, 17 Feb 2012 13:18:37 +0530, Santosh Shilimkar >> <santosh.shilimkar@ti.com> wrote: >>> > > [...] > >>> arch/arm/kernel/smp_twd.c | 4 +++- >>> 1 files changed, 3 insertions(+), 1 deletions(-) >>> >>> diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c >>> index 4285daa..753ae37 100644 >>> --- a/arch/arm/kernel/smp_twd.c >>> +++ b/arch/arm/kernel/smp_twd.c >>> @@ -30,6 +30,7 @@ void __iomem *twd_base; >>> >>> static struct clk *twd_clk; >>> static unsigned long twd_timer_rate; >>> +static bool twd_initialised; >>> >>> static struct clock_event_device __percpu **twd_evt; >>> >>> @@ -129,7 +130,7 @@ static struct notifier_block twd_cpufreq_nb = { >>> >>> static int twd_cpufreq_init(void) >>> { >>> - if (!IS_ERR(twd_clk)) >>> + if ((!IS_ERR(twd_clk)) && twd_initialised) >>> return cpufreq_register_notifier(&twd_cpufreq_nb, >>> CPUFREQ_TRANSITION_NOTIFIER); >> >> Testing twd_evt and *__this_cpu_ptr(twd_evt) should have a similar effect, >> and save the additional variable. >> > Indeed. > Updated patch below. > > From 4d351f59e5dabe065d51304455ee01b191cb56d6 Mon Sep 17 00:00:00 2001 > From: Santosh Shilimkar <santosh.shilimkar@ti.com> > Date: Fri, 17 Feb 2012 11:11:28 +0530 > Subject: [PATCH] ARM: smp_twd: Don't register CPUFREQ notifiers if > local timers are not initialised. > > Current ARM local timer code registers CPUFREQ notifiers even in case > the twd_timer_setup() isn't called. That seems to be wrong and > would eventually lead to kernel crash on the CPU frequency transitions > on the SOCs where the local timer doesn't exist or broken because of > hardware BUG. Fix it by testing twd_evt and *__this_cpu_ptr(twd_evt). > > The issue was observed with v3.3-rc3 and building an OMAP2+ kernel > on OMAP3 SOC which doesn't have TWD. > > Below is the dump for reference : > > Unable to handle kernel paging request at virtual address 007e900 > pgd = cdc20000 > [007e9000] *pgd=00000000 > Internal error: Oops: 5 [#1] SMP > Modules linked in: > CPU: 0 Not tainted (3.3.0-rc3-pm+debug+initramfs #9) > PC is at twd_update_frequency+0x34/0x48 > LR is at twd_update_frequency+0x10/0x48 > pc : [<c001382c>] lr : [<c0013808>] psr: 60000093 > sp : ce311dd8 ip : 00000000 fp : 00000000 > r10: 00000000 r9 : 00000001 r8 : ce310000 > r7 : c0440458 r6 : c00137f8 r5 : 00000000 r4 : c0947a74 > r3 : 00000000 r2 : 007e9000 r1 : 00000000 r0 : 00000000 > Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment usr > Control: 10c5387d Table: 8dc20019 DAC: 00000015 > Process sh (pid: 599, stack limit = 0xce3102f8) > Stack: (0xce311dd8 to 0xce312000) > 1dc0: 6000c > 1de0: 00000001 00000002 00000000 00000000 00000000 00000000 00000 > 1e00: ffffffff c093d8f0 00000000 ce311ebc 00000001 00000001 ce310 > 1e20: c001386c c0437c4c c0e95b60 c0e95ba8 00000001 c0e95bf8 ffff4 > 1e40: 00000000 00000000 c005ef74 ce310000 c0435cf0 ce311ebc 00000 > 1e60: ce352b40 0007a120 c08d5108 c08ba040 c08ba040 c005f030 00000 > 1e80: c08bc554 c032fe2c 0007a120 c08d4b64 ce352b40 c08d8618 ffff8 > 1ea0: c08ba040 c033364c ce311ecc c0433b50 00000002 ffffffea c0330 > 1ec0: 0007a120 0007a120 22222201 00000000 22222222 00000000 ce357 > 1ee0: ce3d6000 cdc2aed8 ce352ba0 c0470164 00000002 c032f47c 00034 > 1f00: c0331cac ce352b40 00000007 c032f6d0 ce352bbc 0003d090 c0930 > 1f20: c093d8bc c03306a4 00000007 ce311f80 00000007 cdc2aec0 ce358 > 1f40: ce8d20c0 00000007 b6fe5000 ce311f80 00000007 ce310000 0000c > 1f60: c000de74 ce987400 ce8d20c0 b6fe5000 00000000 00000000 0000c > 1f80: 00000000 00000000 001fbac8 00000000 00000007 001fbac8 00004 > 1fa0: c000df04 c000dd60 00000007 001fbac8 00000001 b6fe5000 00000 > 1fc0: 00000007 001fbac8 00000007 00000004 b6fe5000 00000000 00202 > 1fe0: 00000000 beb565f8 00101ffc 00008e8c 60000010 00000001 00000 > [<c001382c>] (twd_update_frequency+0x34/0x48) from [<c008ac4c>] ) > [<c008ac4c>] (smp_call_function_single+0x17c/0x1c8) from [<c0013) > [<c0013890>] (twd_cpufreq_transition+0x24/0x30) from [<c0437c4c>) > [<c0437c4c>] (notifier_call_chain+0x44/0x84) from [<c005efe4>] () > [<c005efe4>] (__srcu_notifier_call_chain+0x70/0xa4) from [<c005f) > [<c005f030>] (srcu_notifier_call_chain+0x18/0x20) from [<c032fe2) > [<c032fe2c>] (cpufreq_notify_transition+0xc8/0x1b0) from [<c0333) > [<c033364c>] (omap_target+0x1b4/0x28c) from [<c032f47c>] (__cpuf) > [<c032f47c>] (__cpufreq_driver_target+0x50/0x64) from [<c0331d24) > [<c0331d24>] (cpufreq_set+0x78/0x98) from [<c032f6d0>] (store_sc) > [<c032f6d0>] (store_scaling_setspeed+0x5c/0x74) from [<c03306a4>) > [<c03306a4>] (store+0x58/0x74) from [<c014d868>] (sysfs_write_fi) > [<c014d868>] (sysfs_write_file+0x80/0xb4) from [<c00f2c2c>] (vfs) > [<c00f2c2c>] (vfs_write+0xa8/0x138) from [<c00f2e9c>] (sys_write) > [<c00f2e9c>] (sys_write+0x40/0x6c) from [<c000dd60>] (ret_fast_s) > Code: e594300c e792210c e1a01000 e5840004 (e7930002) > ---[ end trace 5da3b5167c1ecdda ]--- > > Reported-by: Kevin Hilman <khilman@ti.com> > Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> > --- > arch/arm/kernel/smp_twd.c | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c > index 4285daa..265a18a 100644 > --- a/arch/arm/kernel/smp_twd.c > +++ b/arch/arm/kernel/smp_twd.c > @@ -129,7 +129,7 @@ static struct notifier_block twd_cpufreq_nb = { > > static int twd_cpufreq_init(void) > { > - if (!IS_ERR(twd_clk)) > + if ((!twd_evt) && (!__this_cpu_ptr(twd_evt)) && (!IS_ERR(twd_clk))) Erm... Shouldn't that rather be: if (twd_evt && *__this_cpu_ptr(twd_evt) && !IS_ERR(twd_clk)) > return cpufreq_register_notifier(&twd_cpufreq_nb, > CPUFREQ_TRANSITION_NOTIFIER); > M. -- Jazz is not dead. It just smells funny... ^ permalink raw reply [flat|nested] 11+ messages in thread
* SMP local timers and their CPUfreq notifiers setup on OMAP3 2012-02-17 11:06 ` Marc Zyngier @ 2012-02-17 12:28 ` Santosh Shilimkar 2012-02-17 13:32 ` Marc Zyngier ` (2 more replies) 0 siblings, 3 replies; 11+ messages in thread From: Santosh Shilimkar @ 2012-02-17 12:28 UTC (permalink / raw) To: linux-arm-kernel On Friday 17 February 2012 04:36 PM, Marc Zyngier wrote: > On 17/02/12 10:40, Shilimkar, Santosh wrote: >> On Fri, Feb 17, 2012 at 3:17 PM, Marc Zyngier <marc.zyngier@arm.com> wrote: >>> >>> Hi Santosh, >>> >>> On Fri, 17 Feb 2012 13:18:37 +0530, Santosh Shilimkar >>> <santosh.shilimkar@ti.com> wrote: >>>> >> [..] >> diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c >> index 4285daa..265a18a 100644 >> --- a/arch/arm/kernel/smp_twd.c >> +++ b/arch/arm/kernel/smp_twd.c >> @@ -129,7 +129,7 @@ static struct notifier_block twd_cpufreq_nb = { >> >> static int twd_cpufreq_init(void) >> { >> - if (!IS_ERR(twd_clk)) >> + if ((!twd_evt) && (!__this_cpu_ptr(twd_evt)) && (!IS_ERR(twd_clk))) > > Erm... Shouldn't that rather be: > if (twd_evt && *__this_cpu_ptr(twd_evt) && !IS_ERR(twd_clk)) > My bad. You are right. Updated patch below. Tested on OMAP3430 SDP with CPUFREQ enabled. Regards Santosh >From f58c515a9d1a2c729c05a726d5176843381952ae Mon Sep 17 00:00:00 2001 From: Santosh Shilimkar <santosh.shilimkar@ti.com> Date: Fri, 17 Feb 2012 11:11:28 +0530 Subject: [PATCH] ARM: smp_twd: Don't register CPUFREQ notifiers if local timers are not initialised. Current ARM local timer code registers CPUFREQ notifiers even in case the twd_timer_setup() isn't called. That seems to be wrong and would eventually lead to kernel crash on the CPU frequency transitions on the SOCs where the local timer doesn't exist or broken because of hardware BUG. Fix it by testing twd_evt and *__this_cpu_ptr(twd_evt). The issue was observed with v3.3-rc3 and building an OMAP2+ kernel on OMAP3 SOC which doesn't have TWD. Below is the dump for reference : Unable to handle kernel paging request at virtual address 007e900 pgd = cdc20000 [007e9000] *pgd=00000000 Internal error: Oops: 5 [#1] SMP Modules linked in: CPU: 0 Not tainted (3.3.0-rc3-pm+debug+initramfs #9) PC is at twd_update_frequency+0x34/0x48 LR is at twd_update_frequency+0x10/0x48 pc : [<c001382c>] lr : [<c0013808>] psr: 60000093 sp : ce311dd8 ip : 00000000 fp : 00000000 r10: 00000000 r9 : 00000001 r8 : ce310000 r7 : c0440458 r6 : c00137f8 r5 : 00000000 r4 : c0947a74 r3 : 00000000 r2 : 007e9000 r1 : 00000000 r0 : 00000000 Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment usr Control: 10c5387d Table: 8dc20019 DAC: 00000015 Process sh (pid: 599, stack limit = 0xce3102f8) Stack: (0xce311dd8 to 0xce312000) 1dc0: 6000c 1de0: 00000001 00000002 00000000 00000000 00000000 00000000 00000 1e00: ffffffff c093d8f0 00000000 ce311ebc 00000001 00000001 ce310 1e20: c001386c c0437c4c c0e95b60 c0e95ba8 00000001 c0e95bf8 ffff4 1e40: 00000000 00000000 c005ef74 ce310000 c0435cf0 ce311ebc 00000 1e60: ce352b40 0007a120 c08d5108 c08ba040 c08ba040 c005f030 00000 1e80: c08bc554 c032fe2c 0007a120 c08d4b64 ce352b40 c08d8618 ffff8 1ea0: c08ba040 c033364c ce311ecc c0433b50 00000002 ffffffea c0330 1ec0: 0007a120 0007a120 22222201 00000000 22222222 00000000 ce357 1ee0: ce3d6000 cdc2aed8 ce352ba0 c0470164 00000002 c032f47c 00034 1f00: c0331cac ce352b40 00000007 c032f6d0 ce352bbc 0003d090 c0930 1f20: c093d8bc c03306a4 00000007 ce311f80 00000007 cdc2aec0 ce358 1f40: ce8d20c0 00000007 b6fe5000 ce311f80 00000007 ce310000 0000c 1f60: c000de74 ce987400 ce8d20c0 b6fe5000 00000000 00000000 0000c 1f80: 00000000 00000000 001fbac8 00000000 00000007 001fbac8 00004 1fa0: c000df04 c000dd60 00000007 001fbac8 00000001 b6fe5000 00000 1fc0: 00000007 001fbac8 00000007 00000004 b6fe5000 00000000 00202 1fe0: 00000000 beb565f8 00101ffc 00008e8c 60000010 00000001 00000 [<c001382c>] (twd_update_frequency+0x34/0x48) from [<c008ac4c>] ) [<c008ac4c>] (smp_call_function_single+0x17c/0x1c8) from [<c0013) [<c0013890>] (twd_cpufreq_transition+0x24/0x30) from [<c0437c4c>) [<c0437c4c>] (notifier_call_chain+0x44/0x84) from [<c005efe4>] () [<c005efe4>] (__srcu_notifier_call_chain+0x70/0xa4) from [<c005f) [<c005f030>] (srcu_notifier_call_chain+0x18/0x20) from [<c032fe2) [<c032fe2c>] (cpufreq_notify_transition+0xc8/0x1b0) from [<c0333) [<c033364c>] (omap_target+0x1b4/0x28c) from [<c032f47c>] (__cpuf) [<c032f47c>] (__cpufreq_driver_target+0x50/0x64) from [<c0331d24) [<c0331d24>] (cpufreq_set+0x78/0x98) from [<c032f6d0>] (store_sc) [<c032f6d0>] (store_scaling_setspeed+0x5c/0x74) from [<c03306a4>) [<c03306a4>] (store+0x58/0x74) from [<c014d868>] (sysfs_write_fi) [<c014d868>] (sysfs_write_file+0x80/0xb4) from [<c00f2c2c>] (vfs) [<c00f2c2c>] (vfs_write+0xa8/0x138) from [<c00f2e9c>] (sys_write) [<c00f2e9c>] (sys_write+0x40/0x6c) from [<c000dd60>] (ret_fast_s) Code: e594300c e792210c e1a01000 e5840004 (e7930002) ---[ end trace 5da3b5167c1ecdda ]--- Reported-by: Kevin Hilman <khilman@ti.com> Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> --- arch/arm/kernel/smp_twd.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c index 4285daa..9834851 100644 --- a/arch/arm/kernel/smp_twd.c +++ b/arch/arm/kernel/smp_twd.c @@ -129,7 +129,7 @@ static struct notifier_block twd_cpufreq_nb = { static int twd_cpufreq_init(void) { - if (!IS_ERR(twd_clk)) + if (twd_evt && *__this_cpu_ptr(twd_evt) && !IS_ERR(twd_clk)) return cpufreq_register_notifier(&twd_cpufreq_nb, CPUFREQ_TRANSITION_NOTIFIER); -- 1.7.4.1 -------------- next part -------------- A non-text attachment was scrubbed... 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* SMP local timers and their CPUfreq notifiers setup on OMAP3 2012-02-17 12:28 ` Santosh Shilimkar @ 2012-02-17 13:32 ` Marc Zyngier 2012-02-17 18:49 ` Kevin Hilman 2012-02-21 9:11 ` Russell King - ARM Linux 2 siblings, 0 replies; 11+ messages in thread From: Marc Zyngier @ 2012-02-17 13:32 UTC (permalink / raw) To: linux-arm-kernel On 17/02/12 12:28, Santosh Shilimkar wrote: > On Friday 17 February 2012 04:36 PM, Marc Zyngier wrote: >> On 17/02/12 10:40, Shilimkar, Santosh wrote: >>> On Fri, Feb 17, 2012 at 3:17 PM, Marc Zyngier <marc.zyngier@arm.com> wrote: >>>> >>>> Hi Santosh, >>>> >>>> On Fri, 17 Feb 2012 13:18:37 +0530, Santosh Shilimkar >>>> <santosh.shilimkar@ti.com> wrote: >>>>> >>> > > [..] > >>> diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c >>> index 4285daa..265a18a 100644 >>> --- a/arch/arm/kernel/smp_twd.c >>> +++ b/arch/arm/kernel/smp_twd.c >>> @@ -129,7 +129,7 @@ static struct notifier_block twd_cpufreq_nb = { >>> >>> static int twd_cpufreq_init(void) >>> { >>> - if (!IS_ERR(twd_clk)) >>> + if ((!twd_evt) && (!__this_cpu_ptr(twd_evt)) && (!IS_ERR(twd_clk))) >> >> Erm... Shouldn't that rather be: >> if (twd_evt && *__this_cpu_ptr(twd_evt) && !IS_ERR(twd_clk)) >> > My bad. You are right. Updated patch below. > Tested on OMAP3430 SDP with CPUFREQ enabled. > > Regards > Santosh > > From f58c515a9d1a2c729c05a726d5176843381952ae Mon Sep 17 00:00:00 2001 > From: Santosh Shilimkar <santosh.shilimkar@ti.com> > Date: Fri, 17 Feb 2012 11:11:28 +0530 > Subject: [PATCH] ARM: smp_twd: Don't register CPUFREQ notifiers if local > timers are not initialised. > > Current ARM local timer code registers CPUFREQ notifiers even in case > the twd_timer_setup() isn't called. That seems to be wrong and > would eventually lead to kernel crash on the CPU frequency transitions > on the SOCs where the local timer doesn't exist or broken because of > hardware BUG. Fix it by testing twd_evt and *__this_cpu_ptr(twd_evt). > > The issue was observed with v3.3-rc3 and building an OMAP2+ kernel > on OMAP3 SOC which doesn't have TWD. > > Below is the dump for reference : > > Unable to handle kernel paging request at virtual address 007e900 > pgd = cdc20000 > [007e9000] *pgd=00000000 > Internal error: Oops: 5 [#1] SMP > Modules linked in: > CPU: 0 Not tainted (3.3.0-rc3-pm+debug+initramfs #9) > PC is at twd_update_frequency+0x34/0x48 > LR is at twd_update_frequency+0x10/0x48 > pc : [<c001382c>] lr : [<c0013808>] psr: 60000093 > sp : ce311dd8 ip : 00000000 fp : 00000000 > r10: 00000000 r9 : 00000001 r8 : ce310000 > r7 : c0440458 r6 : c00137f8 r5 : 00000000 r4 : c0947a74 > r3 : 00000000 r2 : 007e9000 r1 : 00000000 r0 : 00000000 > Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment usr > Control: 10c5387d Table: 8dc20019 DAC: 00000015 > Process sh (pid: 599, stack limit = 0xce3102f8) > Stack: (0xce311dd8 to 0xce312000) > 1dc0: 6000c > 1de0: 00000001 00000002 00000000 00000000 00000000 00000000 00000 > 1e00: ffffffff c093d8f0 00000000 ce311ebc 00000001 00000001 ce310 > 1e20: c001386c c0437c4c c0e95b60 c0e95ba8 00000001 c0e95bf8 ffff4 > 1e40: 00000000 00000000 c005ef74 ce310000 c0435cf0 ce311ebc 00000 > 1e60: ce352b40 0007a120 c08d5108 c08ba040 c08ba040 c005f030 00000 > 1e80: c08bc554 c032fe2c 0007a120 c08d4b64 ce352b40 c08d8618 ffff8 > 1ea0: c08ba040 c033364c ce311ecc c0433b50 00000002 ffffffea c0330 > 1ec0: 0007a120 0007a120 22222201 00000000 22222222 00000000 ce357 > 1ee0: ce3d6000 cdc2aed8 ce352ba0 c0470164 00000002 c032f47c 00034 > 1f00: c0331cac ce352b40 00000007 c032f6d0 ce352bbc 0003d090 c0930 > 1f20: c093d8bc c03306a4 00000007 ce311f80 00000007 cdc2aec0 ce358 > 1f40: ce8d20c0 00000007 b6fe5000 ce311f80 00000007 ce310000 0000c > 1f60: c000de74 ce987400 ce8d20c0 b6fe5000 00000000 00000000 0000c > 1f80: 00000000 00000000 001fbac8 00000000 00000007 001fbac8 00004 > 1fa0: c000df04 c000dd60 00000007 001fbac8 00000001 b6fe5000 00000 > 1fc0: 00000007 001fbac8 00000007 00000004 b6fe5000 00000000 00202 > 1fe0: 00000000 beb565f8 00101ffc 00008e8c 60000010 00000001 00000 > [<c001382c>] (twd_update_frequency+0x34/0x48) from [<c008ac4c>] ) > [<c008ac4c>] (smp_call_function_single+0x17c/0x1c8) from [<c0013) > [<c0013890>] (twd_cpufreq_transition+0x24/0x30) from [<c0437c4c>) > [<c0437c4c>] (notifier_call_chain+0x44/0x84) from [<c005efe4>] () > [<c005efe4>] (__srcu_notifier_call_chain+0x70/0xa4) from [<c005f) > [<c005f030>] (srcu_notifier_call_chain+0x18/0x20) from [<c032fe2) > [<c032fe2c>] (cpufreq_notify_transition+0xc8/0x1b0) from [<c0333) > [<c033364c>] (omap_target+0x1b4/0x28c) from [<c032f47c>] (__cpuf) > [<c032f47c>] (__cpufreq_driver_target+0x50/0x64) from [<c0331d24) > [<c0331d24>] (cpufreq_set+0x78/0x98) from [<c032f6d0>] (store_sc) > [<c032f6d0>] (store_scaling_setspeed+0x5c/0x74) from [<c03306a4>) > [<c03306a4>] (store+0x58/0x74) from [<c014d868>] (sysfs_write_fi) > [<c014d868>] (sysfs_write_file+0x80/0xb4) from [<c00f2c2c>] (vfs) > [<c00f2c2c>] (vfs_write+0xa8/0x138) from [<c00f2e9c>] (sys_write) > [<c00f2e9c>] (sys_write+0x40/0x6c) from [<c000dd60>] (ret_fast_s) > Code: e594300c e792210c e1a01000 e5840004 (e7930002) > ---[ end trace 5da3b5167c1ecdda ]--- > > Reported-by: Kevin Hilman <khilman@ti.com> > Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> > --- > arch/arm/kernel/smp_twd.c | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c > index 4285daa..9834851 100644 > --- a/arch/arm/kernel/smp_twd.c > +++ b/arch/arm/kernel/smp_twd.c > @@ -129,7 +129,7 @@ static struct notifier_block twd_cpufreq_nb = { > > static int twd_cpufreq_init(void) > { > - if (!IS_ERR(twd_clk)) > + if (twd_evt && *__this_cpu_ptr(twd_evt) && !IS_ERR(twd_clk)) > return cpufreq_register_notifier(&twd_cpufreq_nb, > CPUFREQ_TRANSITION_NOTIFIER); > -- Jazz is not dead. It just smells funny... ^ permalink raw reply [flat|nested] 11+ messages in thread
* SMP local timers and their CPUfreq notifiers setup on OMAP3 2012-02-17 12:28 ` Santosh Shilimkar 2012-02-17 13:32 ` Marc Zyngier @ 2012-02-17 18:49 ` Kevin Hilman 2012-02-18 4:38 ` Shilimkar, Santosh 2012-02-21 9:11 ` Russell King - ARM Linux 2 siblings, 1 reply; 11+ messages in thread From: Kevin Hilman @ 2012-02-17 18:49 UTC (permalink / raw) To: linux-arm-kernel Santosh Shilimkar <santosh.shilimkar@ti.com> writes: > On Friday 17 February 2012 04:36 PM, Marc Zyngier wrote: >> On 17/02/12 10:40, Shilimkar, Santosh wrote: >>> On Fri, Feb 17, 2012 at 3:17 PM, Marc Zyngier <marc.zyngier@arm.com> wrote: >>>> >>>> Hi Santosh, >>>> >>>> On Fri, 17 Feb 2012 13:18:37 +0530, Santosh Shilimkar >>>> <santosh.shilimkar@ti.com> wrote: >>>>> >>> > > [..] > >>> diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c >>> index 4285daa..265a18a 100644 >>> --- a/arch/arm/kernel/smp_twd.c >>> +++ b/arch/arm/kernel/smp_twd.c >>> @@ -129,7 +129,7 @@ static struct notifier_block twd_cpufreq_nb = { >>> >>> static int twd_cpufreq_init(void) >>> { >>> - if (!IS_ERR(twd_clk)) >>> + if ((!twd_evt) && (!__this_cpu_ptr(twd_evt)) && (!IS_ERR(twd_clk))) >> >> Erm... Shouldn't that rather be: >> if (twd_evt && *__this_cpu_ptr(twd_evt) && !IS_ERR(twd_clk)) >> > My bad. You are right. Updated patch below. > Tested on OMAP3430 SDP with CPUFREQ enabled. > > Regards > Santosh > > From f58c515a9d1a2c729c05a726d5176843381952ae Mon Sep 17 00:00:00 2001 > From: Santosh Shilimkar <santosh.shilimkar@ti.com> > Date: Fri, 17 Feb 2012 11:11:28 +0530 > Subject: [PATCH] ARM: smp_twd: Don't register CPUFREQ notifiers if local > timers are not initialised. > > Current ARM local timer code registers CPUFREQ notifiers even in case > the twd_timer_setup() isn't called. That seems to be wrong and > would eventually lead to kernel crash on the CPU frequency transitions > on the SOCs where the local timer doesn't exist or broken because of > hardware BUG. Fix it by testing twd_evt and *__this_cpu_ptr(twd_evt). > > The issue was observed with v3.3-rc3 and building an OMAP2+ kernel > on OMAP3 SOC which doesn't have TWD. > > Below is the dump for reference : > > Unable to handle kernel paging request at virtual address 007e900 > pgd = cdc20000 > [007e9000] *pgd=00000000 > Internal error: Oops: 5 [#1] SMP > Modules linked in: > CPU: 0 Not tainted (3.3.0-rc3-pm+debug+initramfs #9) > PC is at twd_update_frequency+0x34/0x48 > LR is at twd_update_frequency+0x10/0x48 > pc : [<c001382c>] lr : [<c0013808>] psr: 60000093 > sp : ce311dd8 ip : 00000000 fp : 00000000 > r10: 00000000 r9 : 00000001 r8 : ce310000 > r7 : c0440458 r6 : c00137f8 r5 : 00000000 r4 : c0947a74 > r3 : 00000000 r2 : 007e9000 r1 : 00000000 r0 : 00000000 > Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment usr > Control: 10c5387d Table: 8dc20019 DAC: 00000015 > Process sh (pid: 599, stack limit = 0xce3102f8) > Stack: (0xce311dd8 to 0xce312000) > 1dc0: 6000c > 1de0: 00000001 00000002 00000000 00000000 00000000 00000000 00000 > 1e00: ffffffff c093d8f0 00000000 ce311ebc 00000001 00000001 ce310 > 1e20: c001386c c0437c4c c0e95b60 c0e95ba8 00000001 c0e95bf8 ffff4 > 1e40: 00000000 00000000 c005ef74 ce310000 c0435cf0 ce311ebc 00000 > 1e60: ce352b40 0007a120 c08d5108 c08ba040 c08ba040 c005f030 00000 > 1e80: c08bc554 c032fe2c 0007a120 c08d4b64 ce352b40 c08d8618 ffff8 > 1ea0: c08ba040 c033364c ce311ecc c0433b50 00000002 ffffffea c0330 > 1ec0: 0007a120 0007a120 22222201 00000000 22222222 00000000 ce357 > 1ee0: ce3d6000 cdc2aed8 ce352ba0 c0470164 00000002 c032f47c 00034 > 1f00: c0331cac ce352b40 00000007 c032f6d0 ce352bbc 0003d090 c0930 > 1f20: c093d8bc c03306a4 00000007 ce311f80 00000007 cdc2aec0 ce358 > 1f40: ce8d20c0 00000007 b6fe5000 ce311f80 00000007 ce310000 0000c > 1f60: c000de74 ce987400 ce8d20c0 b6fe5000 00000000 00000000 0000c > 1f80: 00000000 00000000 001fbac8 00000000 00000007 001fbac8 00004 > 1fa0: c000df04 c000dd60 00000007 001fbac8 00000001 b6fe5000 00000 > 1fc0: 00000007 001fbac8 00000007 00000004 b6fe5000 00000000 00202 > 1fe0: 00000000 beb565f8 00101ffc 00008e8c 60000010 00000001 00000 > [<c001382c>] (twd_update_frequency+0x34/0x48) from [<c008ac4c>] ) > [<c008ac4c>] (smp_call_function_single+0x17c/0x1c8) from [<c0013) > [<c0013890>] (twd_cpufreq_transition+0x24/0x30) from [<c0437c4c>) > [<c0437c4c>] (notifier_call_chain+0x44/0x84) from [<c005efe4>] () > [<c005efe4>] (__srcu_notifier_call_chain+0x70/0xa4) from [<c005f) > [<c005f030>] (srcu_notifier_call_chain+0x18/0x20) from [<c032fe2) > [<c032fe2c>] (cpufreq_notify_transition+0xc8/0x1b0) from [<c0333) > [<c033364c>] (omap_target+0x1b4/0x28c) from [<c032f47c>] (__cpuf) > [<c032f47c>] (__cpufreq_driver_target+0x50/0x64) from [<c0331d24) > [<c0331d24>] (cpufreq_set+0x78/0x98) from [<c032f6d0>] (store_sc) > [<c032f6d0>] (store_scaling_setspeed+0x5c/0x74) from [<c03306a4>) > [<c03306a4>] (store+0x58/0x74) from [<c014d868>] (sysfs_write_fi) > [<c014d868>] (sysfs_write_file+0x80/0xb4) from [<c00f2c2c>] (vfs) > [<c00f2c2c>] (vfs_write+0xa8/0x138) from [<c00f2e9c>] (sys_write) > [<c00f2e9c>] (sys_write+0x40/0x6c) from [<c000dd60>] (ret_fast_s) > Code: e594300c e792210c e1a01000 e5840004 (e7930002) > ---[ end trace 5da3b5167c1ecdda ]--- > > Reported-by: Kevin Hilman <khilman@ti.com> > Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Tested-by: Kevin Hilman <khilman@ti.com> CAn you please add to Russell's patch system. This needs to be fixed for v3.3-rc. Thanks, Kevin ^ permalink raw reply [flat|nested] 11+ messages in thread
* SMP local timers and their CPUfreq notifiers setup on OMAP3 2012-02-17 18:49 ` Kevin Hilman @ 2012-02-18 4:38 ` Shilimkar, Santosh 0 siblings, 0 replies; 11+ messages in thread From: Shilimkar, Santosh @ 2012-02-18 4:38 UTC (permalink / raw) To: linux-arm-kernel On Sat, Feb 18, 2012 at 12:19 AM, Kevin Hilman <khilman@ti.com> wrote: > Santosh Shilimkar <santosh.shilimkar@ti.com> writes: > >> On Friday 17 February 2012 04:36 PM, Marc Zyngier wrote: >>> On 17/02/12 10:40, Shilimkar, Santosh wrote: >>>> On Fri, Feb 17, 2012 at 3:17 PM, Marc Zyngier <marc.zyngier@arm.com> wrote: >>>>> >>>>> Hi Santosh, >>>>> >>>>> On Fri, 17 Feb 2012 13:18:37 +0530, Santosh Shilimkar >>>>> <santosh.shilimkar@ti.com> wrote: >>>>>> >>>> >> >> [..] >> >>>> diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c >>>> index 4285daa..265a18a 100644 >>>> --- a/arch/arm/kernel/smp_twd.c >>>> +++ b/arch/arm/kernel/smp_twd.c >>>> @@ -129,7 +129,7 @@ static struct notifier_block twd_cpufreq_nb = { >>>> >>>> ?static int twd_cpufreq_init(void) >>>> ?{ >>>> - ? if (!IS_ERR(twd_clk)) >>>> + ? if ((!twd_evt) && (!__this_cpu_ptr(twd_evt)) && (!IS_ERR(twd_clk))) >>> >>> Erm... Shouldn't that rather be: >>> ? ? ?if (twd_evt && *__this_cpu_ptr(twd_evt) && !IS_ERR(twd_clk)) >>> >> My bad. You are right. Updated patch below. >> Tested on OMAP3430 SDP with CPUFREQ enabled. >> >> Regards >> Santosh >> >> From f58c515a9d1a2c729c05a726d5176843381952ae Mon Sep 17 00:00:00 2001 >> From: Santosh Shilimkar <santosh.shilimkar@ti.com> >> Date: Fri, 17 Feb 2012 11:11:28 +0530 >> Subject: [PATCH] ARM: smp_twd: Don't register CPUFREQ notifiers if local >> timers are not initialised. >> >> Current ARM local timer code registers CPUFREQ notifiers even in case >> the twd_timer_setup() isn't called. That seems to be wrong and >> would eventually lead to kernel crash on the CPU frequency transitions >> on the SOCs where the local timer doesn't exist or broken because of >> hardware BUG. Fix it by testing twd_evt and *__this_cpu_ptr(twd_evt). >> >> The issue was observed with v3.3-rc3 and building an OMAP2+ kernel >> on OMAP3 SOC which doesn't have TWD. >> >> Below is the dump for reference : >> >> ?Unable to handle kernel paging request at virtual address 007e900 >> ?pgd = cdc20000 >> ?[007e9000] *pgd=00000000 >> ?Internal error: Oops: 5 [#1] SMP >> ?Modules linked in: >> ?CPU: 0 ? ?Not tainted ?(3.3.0-rc3-pm+debug+initramfs #9) >> ?PC is at twd_update_frequency+0x34/0x48 >> ?LR is at twd_update_frequency+0x10/0x48 >> ?pc : [<c001382c>] ? ?lr : [<c0013808>] ? ?psr: 60000093 >> ?sp : ce311dd8 ?ip : 00000000 ?fp : 00000000 >> ?r10: 00000000 ?r9 : 00000001 ?r8 : ce310000 >> ?r7 : c0440458 ?r6 : c00137f8 ?r5 : 00000000 ?r4 : c0947a74 >> ?r3 : 00000000 ?r2 : 007e9000 ?r1 : 00000000 ?r0 : 00000000 >> ?Flags: nZCv ?IRQs off ?FIQs on ?Mode SVC_32 ?ISA ARM ?Segment usr >> ?Control: 10c5387d ?Table: 8dc20019 ?DAC: 00000015 >> ?Process sh (pid: 599, stack limit = 0xce3102f8) >> ?Stack: (0xce311dd8 to 0xce312000) >> ?1dc0: ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? 6000c >> ?1de0: 00000001 00000002 00000000 00000000 00000000 00000000 00000 >> ?1e00: ffffffff c093d8f0 00000000 ce311ebc 00000001 00000001 ce310 >> ?1e20: c001386c c0437c4c c0e95b60 c0e95ba8 00000001 c0e95bf8 ffff4 >> ?1e40: 00000000 00000000 c005ef74 ce310000 c0435cf0 ce311ebc 00000 >> ?1e60: ce352b40 0007a120 c08d5108 c08ba040 c08ba040 c005f030 00000 >> ?1e80: c08bc554 c032fe2c 0007a120 c08d4b64 ce352b40 c08d8618 ffff8 >> ?1ea0: c08ba040 c033364c ce311ecc c0433b50 00000002 ffffffea c0330 >> ?1ec0: 0007a120 0007a120 22222201 00000000 22222222 00000000 ce357 >> ?1ee0: ce3d6000 cdc2aed8 ce352ba0 c0470164 00000002 c032f47c 00034 >> ?1f00: c0331cac ce352b40 00000007 c032f6d0 ce352bbc 0003d090 c0930 >> ?1f20: c093d8bc c03306a4 00000007 ce311f80 00000007 cdc2aec0 ce358 >> ?1f40: ce8d20c0 00000007 b6fe5000 ce311f80 00000007 ce310000 0000c >> ?1f60: c000de74 ce987400 ce8d20c0 b6fe5000 00000000 00000000 0000c >> ?1f80: 00000000 00000000 001fbac8 00000000 00000007 001fbac8 00004 >> ?1fa0: c000df04 c000dd60 00000007 001fbac8 00000001 b6fe5000 00000 >> ?1fc0: 00000007 001fbac8 00000007 00000004 b6fe5000 00000000 00202 >> ?1fe0: 00000000 beb565f8 00101ffc 00008e8c 60000010 00000001 00000 >> ?[<c001382c>] (twd_update_frequency+0x34/0x48) from [<c008ac4c>] ) >> ?[<c008ac4c>] (smp_call_function_single+0x17c/0x1c8) from [<c0013) >> ?[<c0013890>] (twd_cpufreq_transition+0x24/0x30) from [<c0437c4c>) >> ?[<c0437c4c>] (notifier_call_chain+0x44/0x84) from [<c005efe4>] () >> ?[<c005efe4>] (__srcu_notifier_call_chain+0x70/0xa4) from [<c005f) >> ?[<c005f030>] (srcu_notifier_call_chain+0x18/0x20) from [<c032fe2) >> ?[<c032fe2c>] (cpufreq_notify_transition+0xc8/0x1b0) from [<c0333) >> ?[<c033364c>] (omap_target+0x1b4/0x28c) from [<c032f47c>] (__cpuf) >> ?[<c032f47c>] (__cpufreq_driver_target+0x50/0x64) from [<c0331d24) >> ?[<c0331d24>] (cpufreq_set+0x78/0x98) from [<c032f6d0>] (store_sc) >> ?[<c032f6d0>] (store_scaling_setspeed+0x5c/0x74) from [<c03306a4>) >> ?[<c03306a4>] (store+0x58/0x74) from [<c014d868>] (sysfs_write_fi) >> ?[<c014d868>] (sysfs_write_file+0x80/0xb4) from [<c00f2c2c>] (vfs) >> ?[<c00f2c2c>] (vfs_write+0xa8/0x138) from [<c00f2e9c>] (sys_write) >> ?[<c00f2e9c>] (sys_write+0x40/0x6c) from [<c000dd60>] (ret_fast_s) >> ?Code: e594300c e792210c e1a01000 e5840004 (e7930002) >> ?---[ end trace 5da3b5167c1ecdda ]--- >> >> Reported-by: Kevin Hilman <khilman@ti.com> >> Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com> > > Tested-by: Kevin Hilman <khilman@ti.com> > > CAn you please add to Russell's patch system. ?This needs to be fixed > for v3.3-rc. > Done . 7328/1 in patch system. Regards Santosh ^ permalink raw reply [flat|nested] 11+ messages in thread
* SMP local timers and their CPUfreq notifiers setup on OMAP3 2012-02-17 12:28 ` Santosh Shilimkar 2012-02-17 13:32 ` Marc Zyngier 2012-02-17 18:49 ` Kevin Hilman @ 2012-02-21 9:11 ` Russell King - ARM Linux 2012-02-21 9:26 ` Shilimkar, Santosh 2 siblings, 1 reply; 11+ messages in thread From: Russell King - ARM Linux @ 2012-02-21 9:11 UTC (permalink / raw) To: linux-arm-kernel On Fri, Feb 17, 2012 at 05:58:34PM +0530, Santosh Shilimkar wrote: > diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c > index 4285daa..9834851 100644 > --- a/arch/arm/kernel/smp_twd.c > +++ b/arch/arm/kernel/smp_twd.c > @@ -129,7 +129,7 @@ static struct notifier_block twd_cpufreq_nb = { > > static int twd_cpufreq_init(void) > { > - if (!IS_ERR(twd_clk)) > + if (twd_evt && *__this_cpu_ptr(twd_evt) && !IS_ERR(twd_clk)) You seem to have an additional space before 'if'. ^ permalink raw reply [flat|nested] 11+ messages in thread
* SMP local timers and their CPUfreq notifiers setup on OMAP3 2012-02-21 9:11 ` Russell King - ARM Linux @ 2012-02-21 9:26 ` Shilimkar, Santosh 0 siblings, 0 replies; 11+ messages in thread From: Shilimkar, Santosh @ 2012-02-21 9:26 UTC (permalink / raw) To: linux-arm-kernel On Tue, Feb 21, 2012 at 2:41 PM, Russell King - ARM Linux <linux@arm.linux.org.uk> wrote: > On Fri, Feb 17, 2012 at 05:58:34PM +0530, Santosh Shilimkar wrote: >> diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c >> index 4285daa..9834851 100644 >> --- a/arch/arm/kernel/smp_twd.c >> +++ b/arch/arm/kernel/smp_twd.c >> @@ -129,7 +129,7 @@ static struct notifier_block twd_cpufreq_nb = { >> >> ?static int twd_cpufreq_init(void) >> ?{ >> - ? ? if (!IS_ERR(twd_clk)) >> + ? ? ?if (twd_evt && *__this_cpu_ptr(twd_evt) && !IS_ERR(twd_clk)) > > You seem to have an additional space before 'if'. Yep. Fixed in the updated version in patch system. patch 7336/1 Regards Santosh ^ permalink raw reply [flat|nested] 11+ messages in thread
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2012-02-17 7:48 ` SMP local timers and their CPUfreq notifiers setup on OMAP3 Santosh Shilimkar
2012-02-17 9:47 ` Marc Zyngier
2012-02-17 10:40 ` Shilimkar, Santosh
2012-02-17 10:47 ` Russell King - ARM Linux
2012-02-17 11:06 ` Marc Zyngier
2012-02-17 12:28 ` Santosh Shilimkar
2012-02-17 13:32 ` Marc Zyngier
2012-02-17 18:49 ` Kevin Hilman
2012-02-18 4:38 ` Shilimkar, Santosh
2012-02-21 9:11 ` Russell King - ARM Linux
2012-02-21 9:26 ` Shilimkar, Santosh
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