David Sterba <dsterba@xxxxxxx> writes: > On Mon, Aug 26, 2019 at 06:40:24PM +0300, Nikolay Borisov wrote: >> >> Link: https://bugzilla.kernel.org/show_bug.cgi?id=204371 >> >> Fixes: 69d2480456d1 ("btrfs: use copy_page for copying pages instead of memcpy") >> >> Cc: stable@xxxxxxxxxxxxxxx >> >> Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx> >> >> --- >> >> v2: Using kmem_cache instead of get_zeroed_page() in order to benefit from SLAB debugging features like redzone. >> > >> > I'll take this version, thanks. Though I'm not happy about the allocator >> > behaviour. The kmem cache based fix can be backported independently to >> > 4.19 regardless of the SL*B fixes. >> > >> >> +extern struct kmem_cache *btrfs_bitmap_cachep; >> > >> > I've renamed the cache to btrfs_free_space_bitmap_cachep >> > >> > Reviewed-by: David Sterba <dsterba@xxxxxxxx> >> >> Isn't this obsoleted by >> >> '[PATCH v2 0/2] guarantee natural alignment for kmalloc()' ? > > Yeah, but this would add maybe another whole dev cycle to merge and > release. The reporters of the bug seem to care enough to identify the > problem and propose the fix so I feel like adding the btrfs-specific fix > now is a little favor we can afford. > > The bug is reproduced on an architecture that's not widely tested so > from practical POV I think this adds more coverage which is desirable. Thanks. cheers