On Thu, Aug 31 2017, Zhilong Liu wrote: > On 08/31/2017 08:27 AM, NeilBrown wrote: >> On Wed, Aug 30 2017, Zhilong Liu wrote: >> >>> On 08/29/2017 06:47 PM, NeilBrown wrote: >>>> Thanks. I see what I missed. Please try this patch instead. >>> Hi, Neil; >>> I have tested the following patch, I still got the call-trace after >>> I built with it. >>> If you need other infos, I would append. >> >> Thanks for testing. >> I looked more completely and I think it is easiest just to disable the >> functionality rather than try to fix it. >> Resizing the file in the kernel is extra complexity that I don't >> want to get in to. >> We could adjust the bitmap chunk size so that the file doesn't >> need to grow, but it started getting more complicated than I really >> wanted to deal with. >> If there is anyone actually using file-backed bitmaps who wants to >> be able to resize the array without removing the bitmap first, then >> we can look at the problem again. For now I've sent a patch which >> just returns an error instead of crashing when someone tries to resize >> an array with a file-backed bitmap. > > Hi, Neil; > Shall update the "SIZE CHANGES" under "GROW MODE" of man-page for > resize like following after kernel patch merged? Good idea, but it isn't just "--grow --size". It is anything that changes the size of the array, which includes changing the number of devices in a RAID5 etc. So a more general statement would be better. NeilBrown > > Thanks, > -Zhilong > > diff --git a/mdadm.8.in b/mdadm.8.in > index e0747fb..f0fd1fc 100644 > --- a/mdadm.8.in > +++ b/mdadm.8.in > @@ -2758,6 +2758,11 @@ Also the size of an array cannot be changed while > it has an active > bitmap. If an array has a bitmap, it must be removed before the size > can be changed. Once the change is complete a new bitmap can be created. > > +.PP > +Note: > +.B "--grow --size" > +is not yet supported for external file bitmap. > + > .SS RAID\-DEVICES CHANGES > > A RAID1 array can work with any number of devices from 1 upwards > >> Thanks, >> NeilBrown