在 2019/1/23 上午8:10, Daniel Axtens 写道: > Hi Sasha, > >> This commit has been processed because it contains a "Fixes:" tag, >> fixing commit: 72c270612bd3 bcache: Write out full stripes. > > I added that fixes tag because that was the commit that added the > code. However, I noticed that one of the bug reports mentions that the > problem only arising after v4.8. [1] I don't quite know what to make of > this: perhaps it is a consequence of another change enabling the broken > path. Maybe someone on one of the lists will have an idea. > >From code logic, bcache should not have a discard bio in cache device, otherwise it is a bug. Therefore no matter whether the issue happens before v4.8 kernel, I'd like to have the fix in. >> v4.4.171: Build failed! Errors: >> drivers/md/bcache/writeback.h:71:6: error: implicit declaration of function ‘bio_op’; did you mean ‘bio_rw’? [-Werror=implicit-function-declaration] >> drivers/md/bcache/writeback.h:71:21: error: ‘REQ_OP_DISCARD’ undeclared (first use in this function); did you mean ‘REQ_DISCARD’? >> >> v3.18.132: Build failed! Errors: >> drivers/md/bcache/writeback.h:71:6: error: implicit declaration of function ‘bio_op’; did you mean ‘bio_rw’? [-Werror=implicit-function-declaration] >> drivers/md/bcache/writeback.h:71:21: error: ‘REQ_OP_DISCARD’ undeclared (first use in this function); did you mean ‘REQ_DISCARD’? >> >> >> How should we proceed with this patch? > > The patch seems reasonably easy to backport. Compile-tested only, and > only against v4.4.171. I don't have idea whether stable kernels accept rebased patches, for SUSE kernel I will do back port for all necessary kernel versions. -- Coly Li