Re: [CHECKER] potential deadlocks

Andrew Morton (
Sun, 2 Mar 2003 22:18:06 -0800

Dawson Engler <> wrote:
> BTW, are there known deadlocks (harmless or otherwise)? Debugging
> the checker is a bit hard since false negatives are silent...

Known deadlocks tend to get fixed. But I am surprised that you did not
encounter more of them.

btw, the filesystem transaction operations can be treated as sleeping locks.
So for ext3, journal_start()/journal_stop() may, for lock-ranking purposes,
be treated in the same way as taking and releasing a per-superblock
semaphore. Other filesystems probably have similar restrictions.

Other such "hidden" sleeping locks are lock_sock() and wait_on_inode(). The
latter is rather messy because there is no clear API function which sets

And pte_chain_lock() is a custom spinlock.

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at