Work around a race condition where multiple AFL instances bind to the same CPU#4
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anon8675309 wants to merge 1 commit intobnagy:masterfrom
Open
Work around a race condition where multiple AFL instances bind to the same CPU#4anon8675309 wants to merge 1 commit intobnagy:masterfrom
anon8675309 wants to merge 1 commit intobnagy:masterfrom
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…e multiple instances of AFL will lock onto the same CPU.
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This is the same issue @genewitch found and I can confirm it is also a problem on 64-core machines as well. The issue is that multiple instances of AFL will bind to the the same core. To see this in action:
head -n 25 $OUTPUT_DIR/$TARGET/*/afl-launch.log | grep binding | sort
I also did some experimentation and a 100 ms delay still resulted in two threads binding to CPU #0, but a 250 ms delay seems to reliably avoid any CPU contention.