On Fri, Sep 03, 2021 at 08:48:38AM -0400, Theodore Ts'o wrote:

On Fri, Sep 03, 2021 at 12:05:38PM +0300, Dan Carpenter wrote:

quoted

No one expects error logging functions to sleep so sometimes they are
called with spinlocks held.  In this case the problematic call tree is:

ext2_statfs() <- disables preempt
-> ext2_count_free_inodes()
   -> ext2_get_group_desc()
      -> ext2_error()

Signed-off-by: Dan Carpenter <redacted>
---
This is just from static analysis.  NOT TESTED!

Probably a safer fix would be to just call pr_err() instead of
ext2_error() in ext2_get_group_desc().  I can send that fix instead if
people want.

Looking at both of the ext2_error() calls in ext2_get_group_desc(),
those are really more in the way of assertions rather than warning of
an on-disk corruption issue.  The second "group descriptor not loaded"
should never happen, and the "block_group >= groups_count" should have
been caught via an invalid block number or check by the caller (or an
outright code bug in say ext2_statfs().

So I suspect both of those would be more usefule as a WARN() rather
than a call to ext2_error(), since stack trace would actually provide
more useful data to root causing the issue.  Jan, what do you think?

     	    	    	 	 - Ted

Thanks Ted,

I'll resend with the WARN() change.

regards,
dan carpenter