From: Mikulas Patocka Date: Thu, 10 Dec 2009 23:51:54 +0000 (+0000) Subject: dm snapshot: cope with chunk size larger than origin X-Git-Tag: v2.6.33-rc1~75^2~75 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8e87b9b81b3c370f7e53c1ab6e1c3519ef37a644;p=pandora-kernel.git dm snapshot: cope with chunk size larger than origin Under some special conditions the snapshot hash_size is calculated as zero. This patch instead sets a minimum value of 64, the same as for the pending exception table. rounddown_pow_of_two(0) is an undefined operation (it expands to shift by -1). init_exception_table with an argument of 0 would fail with -ENOMEM. The way to trigger the problem is to create a snapshot with a chunk size that is larger than the origin device. Cc: stable@kernel.org Signed-off-by: Mikulas Patocka Signed-off-by: Alasdair G Kergon --- Reading git-diff-tree failed