Re: [PATCH v3 01/15] stacktrace/x86: add function for detecting reliable stack traces

2016-12-20 Thread Josh Poimboeuf
On Tue, Dec 20, 2016 at 10:39:16AM +0100, Petr Mladek wrote: > On Mon 2016-12-19 11:25:49, Josh Poimboeuf wrote: > > 3) probably some kind of runtime NMI stack checking feature to > >complement objtool, along with a lot of burn time to ensure there are > >no issues, particularly in entry

Re: [PATCH v3 01/15] stacktrace/x86: add function for detecting reliable stack traces

2016-12-20 Thread Petr Mladek
On Mon 2016-12-19 11:25:49, Josh Poimboeuf wrote: > On Mon, Dec 19, 2016 at 05:25:19PM +0100, Miroslav Benes wrote: > > On Thu, 8 Dec 2016, Josh Poimboeuf wrote: > > > > > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig > > > index 215612c..b4a6663 100644 > > > --- a/arch/x86/Kconfig > > > +++

Re: [PATCH v3 01/15] stacktrace/x86: add function for detecting reliable stack traces

2016-12-19 Thread Miroslav Benes
On Mon, 19 Dec 2016, Josh Poimboeuf wrote: > On Mon, Dec 19, 2016 at 05:25:19PM +0100, Miroslav Benes wrote: > > On Thu, 8 Dec 2016, Josh Poimboeuf wrote: > > > > > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig > > > index 215612c..b4a6663 100644 > > > --- a/arch/x86/Kconfig > > > +++

Re: [PATCH v3 01/15] stacktrace/x86: add function for detecting reliable stack traces

2016-12-19 Thread Josh Poimboeuf
On Mon, Dec 19, 2016 at 05:25:19PM +0100, Miroslav Benes wrote: > On Thu, 8 Dec 2016, Josh Poimboeuf wrote: > > > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig > > index 215612c..b4a6663 100644 > > --- a/arch/x86/Kconfig > > +++ b/arch/x86/Kconfig > > @@ -155,6 +155,7 @@ config X86 > >

Re: [PATCH v3 01/15] stacktrace/x86: add function for detecting reliable stack traces

2016-12-19 Thread Miroslav Benes
On Thu, 8 Dec 2016, Josh Poimboeuf wrote: > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig > index 215612c..b4a6663 100644 > --- a/arch/x86/Kconfig > +++ b/arch/x86/Kconfig > @@ -155,6 +155,7 @@ config X86 > select HAVE_PERF_REGS > select HAVE_PERF_USER_STACK_DUMP > select

Re: [PATCH v3 01/15] stacktrace/x86: add function for detecting reliable stack traces

2016-12-16 Thread Josh Poimboeuf
On Fri, Dec 16, 2016 at 02:07:39PM +0100, Petr Mladek wrote: > On Thu 2016-12-08 12:08:26, Josh Poimboeuf wrote: > > For live patching and possibly other use cases, a stack trace is only > > useful if it can be assured that it's completely reliable. Add a new > > save_stack_trace_tsk_reliable()

Re: [PATCH v3 01/15] stacktrace/x86: add function for detecting reliable stack traces

2016-12-16 Thread Petr Mladek
On Thu 2016-12-08 12:08:26, Josh Poimboeuf wrote: > For live patching and possibly other use cases, a stack trace is only > useful if it can be assured that it's completely reliable. Add a new > save_stack_trace_tsk_reliable() function to achieve that. > > Scenarios which indicate that a stack

[PATCH v3 01/15] stacktrace/x86: add function for detecting reliable stack traces

2016-12-08 Thread Josh Poimboeuf
For live patching and possibly other use cases, a stack trace is only useful if it can be assured that it's completely reliable. Add a new save_stack_trace_tsk_reliable() function to achieve that. Scenarios which indicate that a stack trace may be unreliable: - running task - interrupt stack -