[petsc-dev] [petsc-users] strange segv

Mark Adams mfadams at lbl.gov
Sun May 30 08:06:09 CDT 2021


The problem was that I was accessing a device pointer on the host.

Maybe the fact that valgrind did not print a source code line (it was in
host code) is a hint that you are accessing a device pointer?

==77820== Invalid read of size 4
==77820==    at 0x7E69068: LandauKokkosJacobian (in
/gpfs/alpine/csc314/scratch/adams/petsc/arch-summit-opt-gnu-kokkos-notpl-cuda10/lib/libpetsc.so.3.015.0)
==77820==    by 0x7C598AF: LandauFormJacobian_Internal (plexland.c:212)

This access is in landau.kokkos.cxx but no source line number.

Thanks,


On Sun, May 30, 2021 at 12:48 AM Mark Adams <mfadams at lbl.gov> wrote:

>
>
> On Sun, May 30, 2021 at 12:08 AM Barry Smith <bsmith at petsc.dev> wrote:
>
>>
>>    Try without Valgrind, put a CHKMEMQ; just before the call to
>> LandauKokkosJacobian and as its first line. And run with -malloc_debug.
>> This is a less optimal way to find memory corruption but may be more useful
>> in this case.
>>
>
> I don't seem to get anything with this, but I now see that the segv is on
> the 2nd call to LandauKokkosJacobian, which adds the mass matrix, with
> shift. I am working on the mass matrix part now. Let me try adding print
> statements in LandauKokkosJacobian. (DDT failed to trace into that method,
> but let's see).
>
> Thanks,
>
>       CHKMEMQ;
>       PetscPrintf(PETSC_COMM_SELF,"call LandauKokkosJacobian\n");
>       ierr =
> LandauKokkosJacobian(ctx->plex,Nq,Eq_m,IPf,N,xdata,ctx->SData_d,ctx->subThreadBlockSize,shift,ctx->events,JacP);CHKERRQ(ierr);
>
> 00:37 adams/landau-mass-opt *=
> /gpfs/alpine/csc314/scratch/adams/petsc/src/ts/utils/dmplexlandau/tutorials$
> make PETSC_ARCH=arch-summit-opt-gnu-kokkos-notpl-cuda10 -f mymake tiny
> EXTRA='-dm_mat_type aijkokkos -dm_vec_type kokkos -malloc_debug'
> DEVICE=kokkos
> jsrun -n 1 -c 1 -g 1 ./ex2 -dim 2 -ex2_test_type none -dm_landau_Ez 0
> -petscspace_degree 3 -dm_preallocate_only -dm_landau_type p4est
> -dm_landau_ion_masses 1 -dm_landau_ion_charges 1 -dm_landau_thermal_temps
> 4,4 -dm_landau_n 1,1 -ts_monitorx -snes_rtol 1.e-14 -snes_stol 1.e-14
> -snes_monitor -snes_converged_reason -snes_max_it 14 -ts_type beuler
> -ts_exact_final_time stepover -ts_max_snes_failures 1 -ts_rtol 5e-1 -ts_dt
> .5 -ts_max_steps 1 -pc_type lu -ksp_type preonly -dm_landau_amr_levels_max
> 13 -dm_landau_device_type kokkos -dm_mat_type aijkokkos -dm_vec_type kokkos*
> -malloc_debug*
>
>
> [0]FormLandau: 1280 IPs, 80 cells, totDim=32, Nb=16, Nq=16,
> elemMatSize=1024, dim=2, Tab: Nb=16 Nf=2 Np=16 cdim=2 N=1406 shift=0.
>
> *call LandauKokkosJacobian*    0 SNES Function norm 4.974994975313e-03
>
> *call LandauKokkosJacobian*[0]PETSC ERROR:
> ------------------------------------------------------------------------
> [0]PETSC ERROR: Caught signal number 11 SEGV: Segmentation Violation,
> probably memory access out of range
> [0]PETSC ERROR: Try option -start_in_debugger or -on_error_attach_debugger
> [0]PETSC ERROR: or see
> https://www.mcs.anl.gov/petsc/documentation/faq.html#valgrind
> [0]PETSC ERROR: or try http://valgrind.org on GNU/linux and Apple Mac OS
> X to find memory corruption errors
> [0]PETSC ERROR: likely location of problem given in stack below
> [0]PETSC ERROR: ---------------------  Stack Frames
> ------------------------------------
> [0]PETSC ERROR: The EXACT line numbers in the error traceback are not
> available.
> [0]PETSC ERROR: instead the line number of the start of the function is
> given.
> [0]PETSC ERROR: #1 LandauKokkosJacobian() at
> /gpfs/alpine/csc314/scratch/adams/petsc/src/ts/utils/dmplexlandau/kokkos/landau.kokkos.cxx:272
> [0]PETSC ERROR: #2 LandauFormJacobian_Internal() at
> /gpfs/alpine/csc314/scratch/adams/petsc/src/ts/utils/dmplexlandau/plexland.c:66
> [0]PETSC ERROR: #3 LandauIJacobian() at
> /gpfs/alpine/csc314/scratch/adams/petsc/src/ts/utils/dmplexlandau/plexland.c:2093
> [0]PETSC ERROR: #4 TS user implicit Jacobian() at
> /gpfs/alpine/csc314/scratch/adams/petsc/src/ts/interface/ts.c:933
> [0]PETSC ERROR: #5 TSComputeIJacobian() at
> /gpfs/alpine/csc314/scratch/adams/petsc/src/ts/interface/ts.c:916
> [0]PETSC ERROR: #6 SNESTSFormJacobian_Theta() at
> /gpfs/alpine/csc314/scratch/adams/petsc/src/ts/impls/implicit/theta/theta.c:1000
> [0]PETSC ERROR: #7 SNESTSFormJacobian() at
> /gpfs/alpine/csc314/scratch/adams/petsc/src/ts/interface/ts.c:4407
> [0]PETSC ERROR: #8 SNES user Jacobian function() at
> /gpfs/alpine/csc314/scratch/adams/petsc/src/snes/interface/snes.c:2823
> [0]PETSC ERROR: #9 SNESComputeJacobian() at
> /gpfs/alpine/csc314/scratch/adams/petsc/src/snes/interface/snes.c:2782
> [0]PETSC ERROR: #10 SNESSolve() at
> /gpfs/alpine/csc314/scratch/adams/petsc/src/snes/interface/snes.c:4653
> [0]PETSC ERROR: #11 TSTheta_SNESSolve() at
> /gpfs/alpine/csc314/scratch/adams/petsc/src/ts/impls/implicit/theta/theta.c:184
> [0]PETSC ERROR: #12 TSStep_Theta() at
> /gpfs/alpine/csc314/scratch/adams/petsc/src/ts/impls/implicit/theta/theta.c:200
> [0]PETSC ERROR: #13 TSStep() at
> /gpfs/alpine/csc314/scratch/adams/petsc/src/ts/interface/ts.c:3548
> [0]PETSC ERROR: --------------------- Error Message
> --------------------------------------------------------------
>
>
>>
>> On May 29, 2021, at 10:46 PM, Junchao Zhang <junchao.zhang at gmail.com>
>> wrote:
>>
>> try gcc/6.4.0
>> --Junchao Zhang
>>
>>
>> On Sat, May 29, 2021 at 9:50 PM Mark Adams <mfadams at lbl.gov> wrote:
>>
>>> And I grief using gcc-8.1.1 and get this error:
>>>
>>> /autofs/nccs-svm1_sw/summit/gcc/8.1.1/include/c++/8.1.1/type_traits(347):
>>> error: identifier "__ieee128" is undefined
>>>
>>> Any ideas?
>>>
>>> On Sat, May 29, 2021 at 10:39 PM Mark Adams <mfadams at lbl.gov> wrote:
>>>
>>>> And  valgrind sees this. I think the jump to the function is going to
>>>> the wrong place.
>>>> I'm giving up on PGI but can try newer versions of GCC. (what is the
>>>> deal with the range of major releases, 4-10?)
>>>> (as I said this looks like an error that a user is getting so I'd like
>>>> to figure it out).
>>>>
>>>>     0 SNES Function norm 4.974994975313e-03
>>>> ==77820== Invalid read of size 4
>>>> ==77820==    at 0x7E69068: LandauKokkosJacobian (in
>>>> /gpfs/alpine/csc314/scratch/adams/petsc/arch-summit-opt-gnu-kokkos-notpl-cuda10/lib/libpetsc.so.3.015.0)
>>>> ==77820==    by 0x7C598AF: LandauFormJacobian_Internal (plexland.c:212)
>>>> ==77820==    by 0x7C728D3: LandauIJacobian (plexland.c:2107)
>>>> ==77820==    by 0x7C8C26B: TSComputeIJacobian (ts.c:934)
>>>> ==77820==    by 0x7E28337: SNESTSFormJacobian_Theta (theta.c:1007)
>>>> ==77820==    by 0x7CBBFD3: SNESTSFormJacobian (ts.c:4415)
>>>> ==77820==    by 0x7AD84BF: SNESComputeJacobian (snes.c:2824)
>>>> ==77820==    by 0x7BA945B: SNESSolve_NEWTONLS (ls.c:222)
>>>> ==77820==    by 0x7AF336F: SNESSolve (snes.c:4769)
>>>> ==77820==    by 0x7E19D13: TSTheta_SNESSolve (theta.c:185)
>>>> ==77820==    by 0x7E1A8B7: TSStep_Theta (theta.c:223)
>>>> ==77820==    by 0x7CB093F: TSStep (ts.c:3571)
>>>> ==77820==  Address 0x96fff690 is in a --- anonymous segment
>>>> ==77820==
>>>> [0]PETSC ERROR:
>>>> ------------------------------------------------------------------------
>>>> [0]PETSC ERROR: Caught signal number 11 SEGV: Segmentation Violation,
>>>> probably memory access out of range
>>>> [0]PETSC ERROR: Try option -start_in_debugger or
>>>> -on_error_attach_debugger
>>>> [0]PETSC ERROR: or see
>>>> https://www.mcs.anl.gov/petsc/documentation/faq.html#valgrind
>>>> [0]PETSC ERROR: or try http://valgrind.org on GNU/linux and Apple Mac
>>>> OS X to find memory corruption errors
>>>> [0]PETSC ERROR: likely location of problem given in stack below
>>>> [0]PETSC ERROR: ---------------------  Stack Frames
>>>> ------------------------------------
>>>> [0]PETSC ERROR: The EXACT line numbers in the error traceback are not
>>>> available.
>>>> [0]PETSC ERROR: instead the line number of the start of the function is
>>>> given.
>>>> [0]PETSC ERROR: #1 LandauKokkosJacobian() at
>>>> /gpfs/alpine/csc314/scratch/adams/petsc/src/ts/utils/dmplexlandau/kokkos/landau.kokkos.cxx:272
>>>>
>>>> On Sat, May 29, 2021 at 8:46 PM Mark Adams <mfadams at lbl.gov> wrote:
>>>>
>>>>>
>>>>>
>>>>> On Sat, May 29, 2021 at 7:48 PM Barry Smith <bsmith at petsc.dev> wrote:
>>>>>
>>>>>>
>>>>>>    I don't see why it is not running the Kokkos check. Here is the
>>>>>> rule right below the CUDA rule that is apparently running.
>>>>>>
>>>>>> check_build:
>>>>>>         - at echo "Running check examples to verify correct installation"
>>>>>>         - at echo "Using PETSC_DIR=${PETSC_DIR} and
>>>>>> PETSC_ARCH=${PETSC_ARCH}"
>>>>>>         + at cd src/snes/tutorials >/dev/null; ${OMAKE_SELF}
>>>>>> PETSC_ARCH=${PETSC_ARCH}  PETSC_DIR=${PETSC_DIR} clean-legacy
>>>>>>         + at cd src/snes/tutorials >/dev/null; ${OMAKE_SELF}
>>>>>> PETSC_ARCH=${PETSC_ARCH}  PETSC_DIR=${PETSC_DIR} testex19
>>>>>>         + at if [ "${HYPRE_LIB}" != "" ] && [ "${PETSC_WITH_BATCH}" = ""
>>>>>> ] &&  [ "${PETSC_SCALAR}" = "real" ]; then \
>>>>>>           cd src/snes/tutorials >/dev/null; ${OMAKE_SELF}
>>>>>> PETSC_ARCH=${PETSC_ARCH}  PETSC_DIR=${PETSC_DIR}
>>>>>> DIFF=${PETSC_DIR}/lib/petsc/bin/petscdiff runex19_hypre; \
>>>>>>          fi;
>>>>>>         + at if [ "${CUDA_LIB}" != "" ] && [ "${PETSC_WITH_BATCH}" = ""
>>>>>> ] &&  [ "${PETSC_SCALAR}" = "real" ]; then \
>>>>>>           cd src/snes/tutorials >/dev/null; ${OMAKE_SELF}
>>>>>> PETSC_ARCH=${PETSC_ARCH}  PETSC_DIR=${PETSC_DIR}
>>>>>> DIFF=${PETSC_DIR}/lib/petsc/bin/petscdiff runex19_cuda; \
>>>>>>          fi;
>>>>>>         + at if [ "${KOKKOS_KERNELS_LIB}" != "" ] && [
>>>>>> "${PETSC_WITH_BATCH}" = "" ] &&  [ "${PETSC_SCALAR}" = "real" ] && [
>>>>>> "${PETSC_PRECISION}" = "double" ] && [ "${MPI_IS_MPIUNI}" = "0" ]; then \
>>>>>>           cd src/snes/tutorials >/dev/null; ${OMAKE_SELF}
>>>>>> PETSC_ARCH=${PETSC_ARCH}  PETSC_DIR=${PETSC_DIR}
>>>>>> DIFF=${PETSC_DIR}/lib/petsc/bin/petscdiff runex3k_kokkos; \
>>>>>>          fi;
>>>>>>
>>>>>>   Regarding the debugging, if it is just one MPI rank (or even more)
>>>>>> with GDB it will trap the error and show the exact line of source code
>>>>>> where the error occurred and you can poke around at variables to see if
>>>>>> they look corrupt or wrong (for example crazy address in a pointer), I
>>>>>> don't know why your debugger is not giving more useful information.
>>>>>>
>>>>>>
>>>>> This is what I did (in DDT). It stopped at the function call and the
>>>>> data looked fine. I stepped into the call, but didn't get to it. The signal
>>>>> handler was called and I was dead.
>>>>> Maybe I did something in my branch. Can't see what, but I keep probing,
>>>>> Thanks,
>>>>>
>>>>>
>>>>>>   Barry
>>>>>>
>>>>>>
>>>>>> > On May 29, 2021, at 2:16 PM, Mark Adams <mfadams at lbl.gov> wrote:
>>>>>> >
>>>>>> > I am running on Summit with Kokkos-CUDA and I am getting a segv
>>>>>> that looks like some sort of a compile/link mismatch. I also have a user
>>>>>> with a C++ code that is getting strange segvs when calling MatSetValues
>>>>>> with CUDA (I know MatSetValues is not a cupsarse method, but that is the
>>>>>> report that I have). I have no idea if these are related but they both
>>>>>> involve C -- C++ calls ...
>>>>>> >
>>>>>> > I started with a clean build (attached) and I ran in DDT. DDT
>>>>>> stopped at the call in plexland.c to the KokkosLanau operator. I stepped
>>>>>> into this function and then took this screenshot of the stack, with the
>>>>>> Kokkos call and PETSc signal handler.
>>>>>> >
>>>>>> > Make check does not seem to be running Kokkos tests:
>>>>>> >
>>>>>> > 15:02 adams/landau-mass-opt *=
>>>>>> /gpfs/alpine/csc314/scratch/adams/petsc$ make
>>>>>> PETSC_DIR=/gpfs/alpine/csc314/scratch/adams/petsc
>>>>>> PETSC_ARCH=arch-summit-opt-gnu-kokkos-notpl-cuda10 check
>>>>>> > Running check examples to verify correct installation
>>>>>> > Using PETSC_DIR=/gpfs/alpine/csc314/scratch/adams/petsc and
>>>>>> PETSC_ARCH=arch-summit-opt-gnu-kokkos-notpl-cuda10
>>>>>> > C/C++ example src/snes/tutorials/ex19 run successfully with 1 MPI
>>>>>> process
>>>>>> > C/C++ example src/snes/tutorials/ex19 run successfully with 2 MPI
>>>>>> processes
>>>>>> > C/C++ example src/snes/tutorials/ex19 run successfully with cuda
>>>>>> > Completed test examples
>>>>>> >
>>>>>> > Also, I ran this AM with another branch that had not been rebased
>>>>>> with main as recently as this branch (adams/landau-mass-opt).
>>>>>> >
>>>>>> > Any ideas?
>>>>>> > <make.log><configure.log><Screen Shot 2021-05-29 at 2.51.00 PM.png>
>>>>>>
>>>>>>
>>
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