Fix symbolication on 32-bit userspace / 64-bit kernel #2869
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Symbolication is broken on platforms running a 64-bit kernel and a
32-bit userspace. For example, this simple test case can reproduce the
issue: $ bpftrace -e 'profile:hz:99 { @[kstack] = count(); }' .
This is happening because bpftrace requests uint64_t addresses to the
kernel here but then performs an implicit conversion to uintptr_t here
when resolving ksyms, usyms and uids. Fix the issue by changing the
signature of these functions so they receive a uint64_t address instead.
Ideally we should uncomment add_compile_options("-Wconversion") in
bpftrace/CMakeLists.txt to avoid running into simple issues like this in
the future. This patch is one small step towards fixing the current
conversion warnings we have.
[Issue 2854](bpftrace#2854)
Signed-off-by: Jesus Sanchez-Palencia <jesussanp@google.com>
danobi
approved these changes
Dec 6, 2023
|
Nevermind - it's bpftrace that has to run in 32bit mode. Not the test prog. |
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Symbolication is broken on platforms running a 64-bit kernel and a 32-bit userspace. For example, this simple test case can reproduce the issue: $ bpftrace -e 'profile:hz:99 { @[kstack] = count(); }' .
This is happening because bpftrace requests uint64_t addresses to the kernel here but then performs an implicit conversion to uintptr_t here when resolving ksyms, usyms and uids. Fix the issue by changing the signature of these functions so they receive a uint64_t address instead.
Ideally we should uncomment add_compile_options("-Wconversion") in bpftrace/CMakeLists.txt to avoid running into simple issues like this in the future. This patch is one small step towards fixing the current conversion warnings we have.
Issue 2854