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<p class="MsoNormal">I also looked at shadow call stack and got myself very confused:<o:p></o:p></p>
<p class="MsoNormal">Why does is require common sanitizer support? so that it can be checked by clang that the only valid target is AArch64 when -fsanitize=shadow-call-stack is present?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks,<o:p></o:p></p>
<p class="MsoNormal">Zhaoshi<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><b>From:</b> llvm-dev <llvm-dev-bounces@lists.llvm.org> <b>On Behalf Of
</b>Zhaoshi Zheng via llvm-dev<br>
<b>Sent:</b> Monday, March 16, 2020 09:52<br>
<b>To:</b> llvm-dev@lists.llvm.org<br>
<b>Subject:</b> [EXT] [llvm-dev] Enable Safe Stack for Baremetal?<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Hello,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’m assessing the work required to enable Safe Stack for a bare metal target.<o:p></o:p></p>
<p class="MsoNormal">Looking at compiler-rt/lib/safestack/, the current implementation depends on thread support for mutex & storing unsafe stack pointer.<o:p></o:p></p>
<p class="MsoNormal">It also need several system calls: gettid, tgkill, mmap, munmap, mprotect.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Our target doesn’t has all underlying support it needs. My question is: what’s the minimum requirement to port Safe Stack to bare metal?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks,<o:p></o:p></p>
<p class="MsoNormal">Zhaoshi<o:p></o:p></p>
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