Description: ext4: add cond_resched() to ext4_protect_reserved_inode 
References:
 https://patchwork.ozlabs.org/patch/1236118/
Notes:
 bwh> Introduced by fix for CVE-2019-19319, so we can avoid it by
 bwh> applying both fixes at the same time.
Bugs:
upstream: released (5.6-rc2) [af133ade9a40794a37104ecbcc2827c0ea373a3c]
4.19-upstream-stable: released (4.19.105) [a5c03b93e7b5f2080cc574ac65312f0433758158]
4.9-upstream-stable: N/A "Vulnerable code not present"
3.16-upstream-stable: N/A "Vulnerable code not present"
sid: released (5.5.13-1)
4.19-buster-security: released (4.19.118-1)
4.9-stretch-security: N/A "Vulnerable code not present"
3.16-jessie-security: N/A "Vulnerable code not present"