On Fri, Aug 23, 2024 at 04:22:37PM +0800, zhaoyang.huang wrote: > > +#ifndef CONFIG_CMA > bh = sb_getblk(inode->i_sb, map.m_pblk); > +#else > + bh = sb_getblk_gfp(inode->i_sb, map.m_pblk, 0); > +#endif So all of these patches to try to work around your issue with CMA are a bit ugly. But passing in a GFP mask of zero is definitely not the right way to go about thing, since there might be certain GFP masks that are required by a particular block device. What I think you are trying to do is to avoid setting the __GFP_MOVEABLE flag. So in that case, in the CMA path something like this is what you want: bh = getblk_unmoveable(sb->s_bdev, map.m_pblk, sb->s_blocksize); I'd also sugest only trying to use this is the file system has journaling enabled. If the file system is an ext2 file system without a journal, there's no reason avoid using the CMA region --- and I assume the reason why the buffer cache is trying to use the moveable flag is because the amount of non-CMA memory might be a precious resource in some systems. - Ted
