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NVSL / linux-nova

NOVA is a log-structured file system designed for byte-addressable non-volatile memories, developed at the University of California, San Diego.
http://nvsl.ucsd.edu/index.php?path=projects/nova
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Crashing during unlink/rmdir/rename can lead to readdir failing (checksums+parity enabled) #122

Closed pcworld closed 2 years ago

pcworld commented 2 years ago

This report assumes that NOVA's protection features are enabled (nova.metadata_csum=1 nova.data_csum=1 nova.data_parity=1).

During unlink, rmdir and rename operations, there are crash states that lead to readdir operations failing. nova_verify_entry_csum outputs the following error messages: "both entry and its replica fail checksum verification" and "unable to repair entry errors".

The call stacks indirectly called by these system calls appear to share the following: __copy_user_nocache <- nova_update_alter_entry <- (...) <- nova_inplace_update_dentry It appears plausible that they have the same root cause as #121 as they share some of the call stack and is presumably also related to not persisting the checksum (I have not yet verified that completely). I will update once I find out more about the cause.

pcworld commented 2 years ago

I can not reproduce this anymore in master (so this issue is likely a duplicate of #121 and was presumably fixed by PR #129).