Re: [Kgdb-bugreport] [RFC] kdb: Switch kdb_printf to use safer console poll APIs

2020-05-26 Thread Sumit Garg
On Tue, 26 May 2020 at 16:40, Daniel Thompson wrote: > > On Tue, May 26, 2020 at 01:16:17PM +0530, Sumit Garg wrote: > > On Fri, 22 May 2020 at 21:33, Daniel Thompson > > wrote: > > > > > > On Fri, May 22, 2020 at 08:04:31PM +0530, Sumit Garg wrote: > > > > In kgdb NMI context, polling driver

Re: [Kgdb-bugreport] [PATCH v2] kdb: Make kdb_printf robust to run in NMI context

2020-05-26 Thread Sumit Garg
On Fri, 22 May 2020 at 22:05, Daniel Thompson wrote: > > On Fri, May 22, 2020 at 08:03:47PM +0530, Sumit Garg wrote: > > While rounding up CPUs via NMIs, its possible that a rounded up CPU > > maybe holding a console port lock leading to kgdb master CPU stuck in > > a deadlock during invocation

Re: [Kgdb-bugreport] [RFC] kdb: Switch kdb_printf to use safer console poll APIs

2020-05-26 Thread Sumit Garg
On Fri, 22 May 2020 at 21:33, Daniel Thompson wrote: > > On Fri, May 22, 2020 at 08:04:31PM +0530, Sumit Garg wrote: > > In kgdb NMI context, polling driver APIs are more safer to use instead > > of console APIs since the polling drivers know they will execute from > > all sorts of crazy places.

Re: [Kgdb-bugreport] [RFC] kdb: Switch kdb_printf to use safer console poll APIs

2020-05-26 Thread Daniel Thompson
On Tue, May 26, 2020 at 01:16:17PM +0530, Sumit Garg wrote: > On Fri, 22 May 2020 at 21:33, Daniel Thompson > wrote: > > > > On Fri, May 22, 2020 at 08:04:31PM +0530, Sumit Garg wrote: > > > In kgdb NMI context, polling driver APIs are more safer to use instead > > > of console APIs since the

[Kgdb-bugreport] [PATCH] kgdb: Don't call the deinit under spinlock

2020-05-26 Thread Douglas Anderson
When I combined kgdboc_earlycon with an inflight patch titled ("soc: qcom-geni-se: Add interconnect support to fix earlycon crash") [1] things went boom. Specifically I got a crash during the transition between kgdboc_earlycon and the main kgdboc that looked like this: Call trace:

Re: [Kgdb-bugreport] x86/entry vs kgdb

2020-05-26 Thread Daniel Thompson
On Mon, May 25, 2020 at 11:18:32AM +0200, Peter Zijlstra wrote: > On Mon, May 25, 2020 at 10:36:05AM +0200, Peter Zijlstra wrote: > > Hi! > > > > Since you seem to care about kgdb, I figured you might want to fix this > > before I mark it broken on x86 (we've been considering doing that for a > >

Re: [Kgdb-bugreport] x86/entry vs kgdb

2020-05-26 Thread Peter Zijlstra
On Tue, May 26, 2020 at 05:16:21PM +0100, Daniel Thompson wrote: > On Mon, May 25, 2020 at 11:18:32AM +0200, Peter Zijlstra wrote: > > On Mon, May 25, 2020 at 10:36:05AM +0200, Peter Zijlstra wrote: > > > Hi! > > > > > > Since you seem to care about kgdb, I figured you might want to fix this > >