On Tue, Jan 7, 2025 at 12:34 PM RIc Wheeler <ricwheeler@xxxxxxxxx> wrote: > > > On 1/7/25 12:24 PM, Mike Snitzer wrote: > > On Thu, Jan 02, 2025 at 07:28:41PM +0800, Yu Kuai wrote: > >> From: Yu Kuai <yukuai3@xxxxxxxxxx> > >> > >> THe md-linear is removed by commit 849d18e27be9 ("md: Remove deprecated > >> CONFIG_MD_LINEAR") because it has been marked as deprecated for a long > >> time. > >> > >> However, md-linear is used widely for underlying disks with different size, > >> sadly we didn't know this until now, and it's true useful to create > >> partitions and assemble multiple raid and then append one to the other. > >> > >> People have to use dm-linear in this case now, however, they will prefer > >> to minimize the number of involved modules. > >> > >> Signed-off-by: Yu Kuai <yukuai3@xxxxxxxxxx> > > I agree with reinstating md-linear. If/when we do remove md-linear > > (again) we first need a seamless upgrade/conversion option (e.g. mdadm > > updated to use dm-linear in the backend instead of md-linear). > > > Agree with the need for an upgrade/conversion path. > > > > > This patch's header should probably also have this Fixes tag (unclear > > if linux-stable would pick it up but it really is a regression given > > there was no upgrade path offered to md-linear users): > > > > Fixes: 849d18e27be9 md: Remove deprecated CONFIG_MD_LINEAR > > > > Acked-by: Mike Snitzer <snitzer@xxxxxxxxxx> Thanks all for feedback on this move. I agree that reinstating md-linear is the right move for now. Yu Kuai, It appears to me that the path doesn't apply cleanly on the md-6.14 branch: Applying: md: reintroduce md-linear error: patch failed: drivers/md/Makefile:29 error: drivers/md/Makefile: patch does not apply Patch failed at 0001 md: reintroduce md-linear hint: Use 'git am --show-current-patch=diff' to see the failed patch When you have resolved this problem, run "git am --continue". If you prefer to skip this patch, run "git am --skip" instead. To restore the original branch and stop patching, run "git am --abort". Please rebase and resend the patch. Thanks, Song