[petsc-users] Bus Error

[Barry Smith]

https://en.wikipedia.org/wiki/Bus_error <https://en.wikipedia.org/wiki/Bus_error>

But perhaps not true for Intel? 



> On Aug 24, 2020, at 1:06 PM, Matthew Knepley <knepley at gmail.com> wrote:
> 
> On Mon, Aug 24, 2020 at 1:46 PM Barry Smith <bsmith at petsc.dev <mailto:bsmith at petsc.dev>> wrote:
> 
> 
> > On Aug 24, 2020, at 12:39 PM, Jed Brown <jed at jedbrown.org <mailto:jed at jedbrown.org>> wrote:
> > 
> > Barry Smith <bsmith at petsc.dev <mailto:bsmith at petsc.dev>> writes:
> > 
> >>> On Aug 24, 2020, at 12:31 PM, Jed Brown <jed at jedbrown.org <mailto:jed at jedbrown.org>> wrote:
> >>> 
> >>> Barry Smith <bsmith at petsc.dev <mailto:bsmith at petsc.dev>> writes:
> >>> 
> >>>> So if a BLAS errors with SIGBUS then it is always an input error of just not proper double/complex alignment? Or some other very strange thing?
> >>> 
> >>> I would suspect memory corruption.
> >> 
> >> 
> >>  Corruption meaning what specifically?
> >> 
> >>  The routines crashing are dgemv which only take double precision arrays, regardless of what garbage is in those arrays i don't think there can be BUS errors resulting. They don't take integer arrays whose corruption could result in bad indexing and then BUS errors. 
> >> 
> >>  So then it can only be corruption of the pointers passed in, correct?
> > 
> > Such as those pointers pointing into data on the stack with incorrect sizes.
> 
> But won't incorrect sizes "usually" lead to SEGV not SEGBUS?
> 
> My understanding was that roughly memory errors in the heap are SEGV and memory errors on the stack are SIGBUS. Is that not true?
> 
>    Matt
> 
> -- 
> What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead.
> -- Norbert Wiener
> 
> https://www.cse.buffalo.edu/~knepley/ <http://www.cse.buffalo.edu/~knepley/>

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20200824/ba90db4d/attachment.html>