Re: [PATCH next v3 01/15] um: synchronize kmsg_dumper

2021-03-02 Thread Petr Mladek
On Tue 2021-03-02 09:06:07, John Ogness wrote: > On 2021-03-01, Petr Mladek wrote: > >> > diff --git a/arch/um/kernel/kmsg_dump.c b/arch/um/kernel/kmsg_dump.c > >> > index 6516ef1f8274..4869e2cc787c 100644 > >> > --- a/arch/um/kernel/kmsg_dump.c > >> > +++ b/arch/um/kernel/kmsg_dump.c > >> > @@ -1

Re: [PATCH next v3 01/15] um: synchronize kmsg_dumper

2021-03-02 Thread John Ogness
On 2021-03-01, Petr Mladek wrote: >> > diff --git a/arch/um/kernel/kmsg_dump.c b/arch/um/kernel/kmsg_dump.c >> > index 6516ef1f8274..4869e2cc787c 100644 >> > --- a/arch/um/kernel/kmsg_dump.c >> > +++ b/arch/um/kernel/kmsg_dump.c >> > @@ -1,5 +1,6 @@ >> > // SPDX-License-Identifier: GPL-2.0 >> >

Re: [PATCH next v3 01/15] um: synchronize kmsg_dumper

2021-03-01 Thread Petr Mladek
On Mon 2021-03-01 17:16:35, Petr Mladek wrote: > On Thu 2021-02-25 21:24:24, John Ogness wrote: > > The kmsg_dumper can be called from any context and CPU, possibly > > from multiple CPUs simultaneously. Since a static buffer is used > > to retrieve the kernel logs, this buffer must be protected ag

Re: [PATCH next v3 01/15] um: synchronize kmsg_dumper

2021-03-01 Thread Petr Mladek
On Thu 2021-02-25 21:24:24, John Ogness wrote: > The kmsg_dumper can be called from any context and CPU, possibly > from multiple CPUs simultaneously. Since a static buffer is used > to retrieve the kernel logs, this buffer must be protected against > simultaneous dumping. Skip dumping if another c

[PATCH next v3 01/15] um: synchronize kmsg_dumper

2021-02-25 Thread John Ogness
The kmsg_dumper can be called from any context and CPU, possibly from multiple CPUs simultaneously. Since a static buffer is used to retrieve the kernel logs, this buffer must be protected against simultaneous dumping. Skip dumping if another context is already dumping. Signed-off-by: John Ogness