<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body style="overflow-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;"><div><br></div> Hmm, there could be a bug in our handling of the stack when reaches the maximum. It is suppose to just stop collecting additional levels at that point but likely it has not been tested since a lot of refactorizations.<div><br></div><div> What are you doing to have so many stack frames? <br><div><br><blockquote type="cite"><div>On Feb 22, 2023, at 6:32 PM, Sajid Ali Syed <sasyed@fnal.gov> wrote:</div><br class="Apple-interchange-newline"><div><meta charset="UTF-8"><div class="elementToProof ContentPasted1 ContentPasted2" style="font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; background-color: rgb(255, 255, 255);">Hi Matt,<span class="Apple-converted-space"> </span><br><br>Adding `-checkstack` does not prevent the crash, both on my laptop and on the cluster.<span class="Apple-converted-space"> </span><br><br>What does prevent the crash (on my laptop at least) is changing `PETSCSTACKSIZE` from 64 to 256 here :<span class="Apple-converted-space"> </span><a href="https://github.com/petsc/petsc/blob/main/include/petscerror.h#L1153" id="LPlnk969008">https://github.com/petsc/petsc/blob/main/include/petscerror.h#L1153</a><br><br></div><div class="elementToProof" style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 18px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><div id="Signature"><div><div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; background-color: rgb(255, 255, 255);"><br></div><div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;">Thank You,<br><div dir="ltr"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div class="ContentPasted0" style="font-size: 12.8px;">Sajid Ali (he/him) | Research Associate<br>Data Science, Simulation, and Learning Division<br></div><div style="font-size: 12.8px;">Fermi National Accelerator Laboratory<br></div><span style="font-size: 12.8px;"><a href="http://s-sajid-ali.github.io/" target="_blank">s-sajid-ali.github.io</a></span></div></div></div></div></div></div><br></div></div></div></div><div id="appendonsend" style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 18px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"></div><hr tabindex="-1" style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 18px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; display: inline-block; width: 1330.828125px;"><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 18px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;"></span><div id="divRplyFwdMsg" dir="ltr" style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 18px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><font face="Calibri, sans-serif" style="font-size: 11pt;"><b>From:</b><span class="Apple-converted-space"> </span>Matthew Knepley <<a href="mailto:knepley@gmail.com">knepley@gmail.com</a>><br><b>Sent:</b><span class="Apple-converted-space"> </span>Wednesday, February 22, 2023 5:23 PM<br><b>To:</b><span class="Apple-converted-space"> </span>Sajid Ali Syed <<a href="mailto:sasyed@fnal.gov">sasyed@fnal.gov</a>><br><b>Cc:</b><span class="Apple-converted-space"> </span>Barry Smith <<a href="mailto:bsmith@petsc.dev">bsmith@petsc.dev</a>>;<span class="Apple-converted-space"> </span><a href="mailto:petsc-users@mcs.anl.gov">petsc-users@mcs.anl.gov</a><span class="Apple-converted-space"> </span><<a href="mailto:petsc-users@mcs.anl.gov">petsc-users@mcs.anl.gov</a>><br><b>Subject:</b><span class="Apple-converted-space"> </span>Re: [petsc-users] KSP_Solve crashes in debug mode</font><div> </div></div><div style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 18px; font-style: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;"><div dir="ltr"><div dir="ltr">On Wed, Feb 22, 2023 at 6:18 PM Sajid Ali Syed via petsc-users <<a href="mailto:petsc-users@mcs.anl.gov">petsc-users@mcs.anl.gov</a>> wrote:<br></div><div class="x_gmail_quote"><blockquote class="x_gmail_quote" style="margin: 0px 0px 0px 0.8ex; border-left-width: 1px; border-left-style: solid; border-left-color: rgb(204, 204, 204); padding-left: 1ex;"><div class="x_msg-8224865940736422939"><div dir="ltr"><div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; background-color: rgb(255, 255, 255);">One thing to note in relation to the trace attached in the previous email is that there are no warnings until the 36<span><sup>th</sup> call to KSP_Solve. The first error (as indicated by ASAN) occurs somewhere before the 40<span><sup>th</sup> call to KSP_Solve (part of what the application marks as turn 10 of the propagator). The crash finally occurs on the 43<span><sup>rd</sup> call to KSP_solve.</span></span></span></div></div></div></blockquote><div><br></div><div>Looking at the trace, it appears that stack handling is messed up and eventually it causes the crash. This can happen when</div><div>PetscFunctionBegin is not matched up with PetscFunctionReturn. Can you try running this with</div><div><br></div><div> -checkstack</div><div><br></div><div> Thanks,</div><div><br></div><div> Matt</div><div> </div><blockquote class="x_gmail_quote" style="margin: 0px 0px 0px 0.8ex; border-left-width: 1px; border-left-style: solid; border-left-color: rgb(204, 204, 204); padding-left: 1ex;"><div class="x_msg-8224865940736422939"><div dir="ltr"><div><div id="x_m_-8224865940736422939Signature"><div><div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;">Thank You,<br><div dir="ltr"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div style="font-size: 12.8px;">Sajid Ali (he/him) | Research Associate<br>Data Science, Simulation, and Learning Division<br></div><div style="font-size: 12.8px;">Fermi National Accelerator Laboratory<br></div><span style="font-size: 12.8px;"><a href="https://urldefense.proofpoint.com/v2/url?u=http-3A__s-2Dsajid-2Dali.github.io&d=DwMFaQ&c=gRgGjJ3BkIsb5y6s49QqsA&r=w-DPglgoOUOz8eiEyHKz0g&m=q5fD8r624Cr0Ow4AKTmgeLtq_M--q_KdGYMkBNiKOMDa8o82C8P97vdCRcxrqTCF&s=oNWxB3zDYTHODeZK9VCibIVqSo7DnwsJjSr6IgIPs2M&e=" target="_blank">s-sajid-ali.github.io</a></span></div></div></div></div></div></div><br></div></div></div></div><div id="x_m_-8224865940736422939appendonsend"></div><hr style="display: inline-block; width: 1313.265625px;"><div id="x_m_-8224865940736422939divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size: 11pt;"><b>From:</b><span class="Apple-converted-space"> </span>Sajid Ali Syed <<a href="mailto:sasyed@fnal.gov" target="_blank">sasyed@fnal.gov</a>><br><b>Sent:</b><span class="Apple-converted-space"> </span>Wednesday, February 22, 2023 5:11 PM<br><b>To:</b><span class="Apple-converted-space"> </span>Barry Smith <<a href="mailto:bsmith@petsc.dev" target="_blank">bsmith@petsc.dev</a>><br><b>Cc:</b><span class="Apple-converted-space"> </span><a href="mailto:petsc-users@mcs.anl.gov" target="_blank">petsc-users@mcs.anl.gov</a><span class="Apple-converted-space"> </span><<a href="mailto:petsc-users@mcs.anl.gov" target="_blank">petsc-users@mcs.anl.gov</a>><br><b>Subject:</b><span class="Apple-converted-space"> </span>Re: [petsc-users] KSP_Solve crashes in debug mode</font><div> </div></div><div dir="ltr"><div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; background-color: rgb(255, 255, 255);">Hi Barry,<span class="Apple-converted-space"> </span><br><br>Thanks a lot for fixing this issue. I ran the same problem on a linux machine and have the following trace for the same crash (with ASAN turned on for both PETSc (on the latest commit of the branch) and the application) :<span class="Apple-converted-space"> </span><a href="https://urldefense.proofpoint.com/v2/url?u=https-3A__gist.github.com_s-2Dsajid-2Dali_85bdf689eb8452ef8702c214c4df6940&d=DwMFaQ&c=gRgGjJ3BkIsb5y6s49QqsA&r=w-DPglgoOUOz8eiEyHKz0g&m=q5fD8r624Cr0Ow4AKTmgeLtq_M--q_KdGYMkBNiKOMDa8o82C8P97vdCRcxrqTCF&s=Z8JyNKYXjUZE4DXYKvjxTOG4HZUA95U6z750WC6gUCo&e=" id="x_m_-8224865940736422939LPlnkOWALinkPreview" target="_blank">https://gist.github.com/s-sajid-ali/85bdf689eb8452ef8702c214c4df6940</a><br><br>The trace seems to indicate a couple of buffer overflows, one of which causes the crash. I'm not sure as to what causes them.<span class="Apple-converted-space"> </span><br></div><div><div id="x_m_-8224865940736422939x_Signature"><div><div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; background-color: rgb(255, 255, 255);"><br></div><div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;">Thank You,<br><div dir="ltr"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div style="font-size: 12.8px;">Sajid Ali (he/him) | Research Associate<br>Data Science, Simulation, and Learning Division<br></div><div style="font-size: 12.8px;">Fermi National Accelerator Laboratory<br></div><span style="font-size: 12.8px;"><a href="https://urldefense.proofpoint.com/v2/url?u=http-3A__s-2Dsajid-2Dali.github.io&d=DwMFaQ&c=gRgGjJ3BkIsb5y6s49QqsA&r=w-DPglgoOUOz8eiEyHKz0g&m=q5fD8r624Cr0Ow4AKTmgeLtq_M--q_KdGYMkBNiKOMDa8o82C8P97vdCRcxrqTCF&s=oNWxB3zDYTHODeZK9VCibIVqSo7DnwsJjSr6IgIPs2M&e=" target="_blank">s-sajid-ali.github.io</a></span></div></div></div></div></div></div><br></div></div></div></div><div id="x_m_-8224865940736422939x_appendonsend"></div><hr style="display: inline-block; width: 1313.265625px;"><div id="x_m_-8224865940736422939x_divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size: 11pt;"><b>From:</b><span class="Apple-converted-space"> </span>Barry Smith <<a href="mailto:bsmith@petsc.dev" target="_blank">bsmith@petsc.dev</a>><br><b>Sent:</b><span class="Apple-converted-space"> </span>Wednesday, February 15, 2023 2:01 PM<br><b>To:</b><span class="Apple-converted-space"> </span>Sajid Ali Syed <<a href="mailto:sasyed@fnal.gov" target="_blank">sasyed@fnal.gov</a>><br><b>Cc:</b><span class="Apple-converted-space"> </span><a href="mailto:petsc-users@mcs.anl.gov" target="_blank">petsc-users@mcs.anl.gov</a><span class="Apple-converted-space"> </span><<a href="mailto:petsc-users@mcs.anl.gov" target="_blank">petsc-users@mcs.anl.gov</a>><br><b>Subject:</b><span class="Apple-converted-space"> </span>Re: [petsc-users] KSP_Solve crashes in debug mode</font><div> </div></div><div><div><br></div><a href="https://urldefense.proofpoint.com/v2/url?u=https-3A__gitlab.com_petsc_petsc_-2D_merge-5Frequests_6075&d=DwMFaQ&c=gRgGjJ3BkIsb5y6s49QqsA&r=w-DPglgoOUOz8eiEyHKz0g&m=P7R0CW9R-fGNfm2q3yTL-ehqhM5N9-r8hHBLNgDetm9-7jxVqNsujIZ2hdnhVrVX&s=QwRI_DzGnCHagpaQSC4MPPEUnC4aAkbMwdG1eg_QUII&e=" target="_blank">https://gitlab.com/petsc/petsc/-/merge_requests/6075</a> should fix the possible recursive error condition Matt pointed out<div><br><div><br><blockquote type="cite"><div>On Feb 9, 2023, at 6:24 PM, Matthew Knepley <<a href="mailto:knepley@gmail.com" target="_blank">knepley@gmail.com</a>> wrote:</div><br><div><div dir="ltr"><div dir="ltr">On Thu, Feb 9, 2023 at 6:05 PM Sajid Ali Syed via petsc-users <<a href="mailto:petsc-users@mcs.anl.gov" target="_blank">petsc-users@mcs.anl.gov</a>> wrote:<br></div><div><blockquote style="margin: 0px 0px 0px 0.8ex; border-left-width: 1px; border-left-style: solid; border-left-color: rgb(204, 204, 204); padding-left: 1ex;"><div><div dir="ltr"><div><p style="margin: 0px 0px 1.2em;">I added “-malloc_debug” in a .petscrc file and ran it again. The backtrace from lldb is in the attached file. The crash now seems to be at:</p><pre style="font-family: Consolas, Inconsolata, Courier, monospace; font-size: 1em; line-height: 1.2em; margin: 1.2em 0px;"><code style="font-size: 0.85em; font-family: Consolas, Inconsolata, Courier, monospace; margin: 0px 0.15em; background-color: rgb(248, 248, 248); white-space: pre-wrap; overflow: auto; border-radius: 3px; border: 1px solid rgb(204, 204, 204); padding: 0.5em 0.7em; display: block;">Process 32660 stopped* thread #1, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=2, address=0x16f603fb8)
frame #0: 0x0000000112ecc8f8 libpetsc.3.018.dylib`PetscFPrintf(comm=0, fd=0x0000000000000000, format=0x0000000000000000) at mprint.c:601
598 `PetscViewerASCIISynchronizedPrintf()`, `PetscSynchronizedFlush()`
599 @*/
600 PetscErrorCode PetscFPrintf(MPI_Comm comm, FILE *fd, const char format[], ...)
-> 601 {
602 PetscMPIInt rank;
603
604 PetscFunctionBegin;
(lldb) frame info
frame #0: 0x0000000112ecc8f8 libpetsc.3.018.dylib`PetscFPrintf(comm=0, fd=0x0000000000000000, format=0x0000000000000000) at mprint.c:601
(lldb)
</code></pre><p style="margin: 0px 0px 1.2em;">The trace seems to indicate some sort of infinite loop causing an overflow.<br></p></div></div></div></blockquote><div><br></div><div>Yes, I have also seen this. What happens is that we have a memory error. The error is reported inside PetscMallocValidate()</div><div>using PetscErrorPrintf, which eventually calls PetscCallMPI, which calls PetscMallocValidate again, which fails. We need to</div><div>remove all error checking from the prints inside Validate.</div><div><br></div><div> Thanks,</div><div><br></div><div> Matt</div><div> </div><blockquote style="margin: 0px 0px 0px 0.8ex; border-left-width: 1px; border-left-style: solid; border-left-color: rgb(204, 204, 204); padding-left: 1ex;"><div><div dir="ltr"><div><p style="margin: 0px 0px 1.2em;">PS: I'm using a arm64 mac, so I don't have access to valgrind.<span class="Apple-converted-space"> </span><br><br>Thank You,<br>Sajid Ali (he/him) | Research Associate<br>Scientific Computing Division<br>Fermi National Accelerator Laboratory<a href="https://urldefense.proofpoint.com/v2/url?u=http-3A__s-2Dsajid-2Dali.github.io_&d=DwMFaQ&c=gRgGjJ3BkIsb5y6s49QqsA&r=w-DPglgoOUOz8eiEyHKz0g&m=P7R0CW9R-fGNfm2q3yTL-ehqhM5N9-r8hHBLNgDetm9-7jxVqNsujIZ2hdnhVrVX&s=JA1u9AHcO8HqY5oCgbEy-ghtKRjURlRDwdmxP-9YJac&e=" target="_blank"><br>s-sajid-ali.github.io</a></p><div title="MDH:PGRpdiBzdHlsZT0iZm9udC1mYW1pbHk6IENhbGlicmksIEFyaWFsLCBIZWx2ZXRpY2EsIHNhbnMt
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LjhweCI+RmVybWkgTmF0aW9uYWwgQWNjZWxlcmF0b3IgTGFib3JhdG9yeTxicj4KPC9kaXY+Cjxz
cGFuIHN0eWxlPSJmb250LXNpemU6MTIuOHB4Ij48YSBocmVmPSJodHRwOi8vcy1zYWppZC1hbGku
Z2l0aHViLmlvIiB0YXJnZXQ9Il9ibGFuayI+cy1zYWppZC1hbGkuZ2l0aHViLmlvPC9hPjwvc3Bh
bj48L2Rpdj4KPC9kaXY+CjwvZGl2Pgo8L2Rpdj4KPC9kaXY+CjwvZGl2Pjxicj48ZGl2IHN0eWxl
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dj48L2Rpdj48L2Rpdj48L2Rpdj4=" style="height: 0px; width: 0px; max-height: 0px; max-width: 0px; overflow: hidden; font-size: 0em; padding: 0px; margin: 0px;"></div></div></div></div></blockquote></div><br clear="all"><div><br></div>--<span class="Apple-converted-space"> </span><br><div dir="ltr"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div>What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead.<br>-- Norbert Wiener</div><div><br></div><div><a href="https://urldefense.proofpoint.com/v2/url?u=http-3A__www.cse.buffalo.edu_-7Eknepley_&d=DwMFaQ&c=gRgGjJ3BkIsb5y6s49QqsA&r=w-DPglgoOUOz8eiEyHKz0g&m=P7R0CW9R-fGNfm2q3yTL-ehqhM5N9-r8hHBLNgDetm9-7jxVqNsujIZ2hdnhVrVX&s=CdEZKWQbBYiD2pzU3Az_EDIGUTBNkNHwSoD2n_2098Y&e=" target="_blank">https://www.cse.buffalo.edu/~knepley/</a><br></div></div></div></div></div></div></div></div></div></blockquote></div><br></div></div></div></div></div></blockquote></div><br clear="all"><div><br></div>--<span class="Apple-converted-space"> </span><br><div dir="ltr" class="x_gmail_signature"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div>What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead.<br>-- Norbert Wiener</div><div><br></div><div><a href="https://urldefense.proofpoint.com/v2/url?u=http-3A__www.cse.buffalo.edu_-7Eknepley_&d=DwMFaQ&c=gRgGjJ3BkIsb5y6s49QqsA&r=w-DPglgoOUOz8eiEyHKz0g&m=q5fD8r624Cr0Ow4AKTmgeLtq_M--q_KdGYMkBNiKOMDa8o82C8P97vdCRcxrqTCF&s=Hkn4IxPABZIeY0m9o_VGFHJ4ntffqbtyd3fddpbZw7I&e=" target="_blank">https://www.cse.buffalo.edu/~knepley/</a></div></div></div></div></div></div></div></div></div></div></blockquote></div><br></div></body></html>