RE: [PATCH] serial: sh-sci: prevent lockup on full TTY buffers

Hi, > From: Ulrich Hecht, Sent: Thursday, February 15, 2018 9:02 PM > > When the TTY buffers fill up to the configured maximum, a system lockup > occurs: > > [ 598.820128] INFO: rcu_preempt detected stalls on CPUs/tasks: > [ 598.825796] 0-...!: (1 GPs behind) idle=5a6/2/0 softirq=1974/1974

Re: [PATCH] serial: sh-sci: prevent lockup on full TTY buffers

Hi Greg, On Fri, Feb 16, 2018 at 7:44 PM, Greg KH wrote: > On Thu, Feb 15, 2018 at 01:02:27PM +0100, Ulrich Hecht wrote: >> When the TTY buffers fill up to the configured maximum, a system lockup >> occurs: >> >> [ 598.820128] INFO: rcu_preempt detected stalls on CPUs/tasks: >>

Re: [PATCH] serial: sh-sci: prevent lockup on full TTY buffers

Hi Uli, On Fri, Feb 16, 2018 at 3:27 PM, Ulrich Hecht wrote: > On Thu, Feb 15, 2018 at 2:12 PM, Wolfram Sang wrote: >>> This can be prevented by doing a dummy read of the RX data register. >> >> Just so I understand the issue correctly: We are

Re: [PATCH] serial: sh-sci: prevent lockup on full TTY buffers

On Thu, Feb 15, 2018 at 01:02:27PM +0100, Ulrich Hecht wrote: > When the TTY buffers fill up to the configured maximum, a system lockup > occurs: > > [ 598.820128] INFO: rcu_preempt detected stalls on CPUs/tasks: > [ 598.825796] 0-...!: (1 GPs behind) idle=5a6/2/0 softirq=1974/1974 fqs=1 > [

Re: [PATCH] serial: sh-sci: prevent lockup on full TTY buffers

On Thu, Feb 15, 2018 at 2:12 PM, Wolfram Sang wrote: > >> This can be prevented by doing a dummy read of the RX data register. > > Just so I understand the issue correctly: We are reading the register to > throw the content away to prevent it being used in the TTY buffers?

Re: [PATCH] serial: sh-sci: prevent lockup on full TTY buffers

> This can be prevented by doing a dummy read of the RX data register. Just so I understand the issue correctly: We are reading the register to throw the content away to prevent it being used in the TTY buffers? signature.asc Description: PGP signature