Re: [PATCH] tty: serial: msm: Fix lock init issue with earlycon

2014-10-21 Thread Peter Hurley
On 10/20/2014 06:20 PM, Stephen Boyd wrote: > On 10/20, Stephen Boyd wrote: >> On 10/20, Peter Hurley wrote: >>> >>> FWIW, __msm_console_write() is a deadlock-waiting-to_happen since it does >>> not disable interrupts with spin_lock_irqsave(). >>> >> >> Yeah we should fix that. As far as I can

Re: [PATCH] tty: serial: msm: Fix lock init issue with earlycon

2014-10-21 Thread Peter Hurley
On 10/20/2014 06:20 PM, Stephen Boyd wrote: On 10/20, Stephen Boyd wrote: On 10/20, Peter Hurley wrote: FWIW, __msm_console_write() is a deadlock-waiting-to_happen since it does not disable interrupts with spin_lock_irqsave(). Yeah we should fix that. As far as I can tell we've never used

Re: [PATCH] tty: serial: msm: Fix lock init issue with earlycon

2014-10-20 Thread Stephen Boyd
On 10/20, Stephen Boyd wrote: > On 10/20, Peter Hurley wrote: > > > > FWIW, __msm_console_write() is a deadlock-waiting-to_happen since it does > > not disable interrupts with spin_lock_irqsave(). > > > > Yeah we should fix that. As far as I can tell we've never used > the irqsave variant of

Re: [PATCH] tty: serial: msm: Fix lock init issue with earlycon

2014-10-20 Thread Stephen Boyd
On 10/20, Peter Hurley wrote: > On 10/20/2014 02:27 PM, Stephen Boyd wrote: > > On 10/17/2014 06:13 AM, Kumar Gala wrote: > >> With CONFIG_DEBUG_SPINLOCK enabled we see: > >> > >> BUG: spinlock bad magic on CPU#0, swapper/0 > >> lock: early_console_dev+0x8/0x160, .magic: , .owner: /-1,

Re: [PATCH] tty: serial: msm: Fix lock init issue with earlycon

2014-10-20 Thread Peter Hurley
On 10/20/2014 02:27 PM, Stephen Boyd wrote: > On 10/17/2014 06:13 AM, Kumar Gala wrote: >> With CONFIG_DEBUG_SPINLOCK enabled we see: >> >> BUG: spinlock bad magic on CPU#0, swapper/0 >> lock: early_console_dev+0x8/0x160, .magic: , .owner: /-1, >> .owner_cpu: 0 >> CPU: 0 PID: 0 Comm:

Re: [PATCH] tty: serial: msm: Fix lock init issue with earlycon

2014-10-20 Thread Stephen Boyd
On 10/17/2014 06:13 AM, Kumar Gala wrote: With CONFIG_DEBUG_SPINLOCK enabled we see: BUG: spinlock bad magic on CPU#0, swapper/0 lock: early_console_dev+0x8/0x160, .magic: , .owner: /-1, .owner_cpu: 0 CPU: 0 PID: 0 Comm: swapper Not tainted 3.17.0-09733-gb446b33-dirty #18 [...]

Re: [PATCH] tty: serial: msm: Fix lock init issue with earlycon

2014-10-20 Thread Stephen Boyd
On 10/17/2014 06:13 AM, Kumar Gala wrote: With CONFIG_DEBUG_SPINLOCK enabled we see: BUG: spinlock bad magic on CPU#0, swapper/0 lock: early_console_dev+0x8/0x160, .magic: , .owner: none/-1, .owner_cpu: 0 CPU: 0 PID: 0 Comm: swapper Not tainted 3.17.0-09733-gb446b33-dirty #18 [...]

Re: [PATCH] tty: serial: msm: Fix lock init issue with earlycon

2014-10-20 Thread Peter Hurley
On 10/20/2014 02:27 PM, Stephen Boyd wrote: On 10/17/2014 06:13 AM, Kumar Gala wrote: With CONFIG_DEBUG_SPINLOCK enabled we see: BUG: spinlock bad magic on CPU#0, swapper/0 lock: early_console_dev+0x8/0x160, .magic: , .owner: none/-1, .owner_cpu: 0 CPU: 0 PID: 0 Comm: swapper Not

Re: [PATCH] tty: serial: msm: Fix lock init issue with earlycon

2014-10-20 Thread Stephen Boyd
On 10/20, Peter Hurley wrote: On 10/20/2014 02:27 PM, Stephen Boyd wrote: On 10/17/2014 06:13 AM, Kumar Gala wrote: With CONFIG_DEBUG_SPINLOCK enabled we see: BUG: spinlock bad magic on CPU#0, swapper/0 lock: early_console_dev+0x8/0x160, .magic: , .owner: none/-1,

Re: [PATCH] tty: serial: msm: Fix lock init issue with earlycon

2014-10-20 Thread Stephen Boyd
On 10/20, Stephen Boyd wrote: On 10/20, Peter Hurley wrote: FWIW, __msm_console_write() is a deadlock-waiting-to_happen since it does not disable interrupts with spin_lock_irqsave(). Yeah we should fix that. As far as I can tell we've never used the irqsave variant of the lock in

[PATCH] tty: serial: msm: Fix lock init issue with earlycon

2014-10-17 Thread Kumar Gala
With CONFIG_DEBUG_SPINLOCK enabled we see: BUG: spinlock bad magic on CPU#0, swapper/0 lock: early_console_dev+0x8/0x160, .magic: , .owner: /-1, .owner_cpu: 0 CPU: 0 PID: 0 Comm: swapper Not tainted 3.17.0-09733-gb446b33-dirty #18 Call trace: [] dump_backtrace+0x0/0x140 []

[PATCH] tty: serial: msm: Fix lock init issue with earlycon

2014-10-17 Thread Kumar Gala
With CONFIG_DEBUG_SPINLOCK enabled we see: BUG: spinlock bad magic on CPU#0, swapper/0 lock: early_console_dev+0x8/0x160, .magic: , .owner: none/-1, .owner_cpu: 0 CPU: 0 PID: 0 Comm: swapper Not tainted 3.17.0-09733-gb446b33-dirty #18 Call trace: [c0087ba0] dump_backtrace+0x0/0x140