Thanks for the comments.. more below. On 10/21/2015 05:12 PM, Qu Wenruo wrote:
Anand Jain wrote on 2015/10/21 16:45 +0800:mkfs from latest btrfs-progs will enable latest default features, and if the kernel is down-rev and does not support a latest default feature then mount fails, as expected. This patch disables default features based on the running kernel. Signed-off-by: Anand Jain <anand.jain@xxxxxxxxxx> --- mkfs.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/mkfs.c b/mkfs.c index a5802f7..2b9d734 100644 --- a/mkfs.c +++ b/mkfs.c @@ -1357,10 +1357,13 @@ int main(int ac, char **av) int dev_cnt = 0; int saved_optind; char fs_uuid[BTRFS_UUID_UNPARSED_SIZE] = { 0 }; - u64 features = BTRFS_MKFS_DEFAULT_FEATURES; + u64 features; struct mkfs_allocation allocation = { 0 }; struct btrfs_mkfs_config mkfs_cfg; + features = btrfs_features_allowed_by_kernel(); + features &= BTRFS_MKFS_DEFAULT_FEATURES; +Despite the problem of btrfs_features_allowed_by_kernel() I mentioned in previous mail, the behavior is a little aggressive for me. So a user with old kernel won't be able to create a filesystem with newer feature forever. Maybe the user are just making btrfs for his or her newer kernel?
I am not understanding the complete picture here, is there any example that you can quote. ?
Thanks, Anand
IMHO, it's better to output a warning other than just change features without any information. Thanks, Quwhile(1) { int c; static const struct option long_options[] = {-- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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