On Tue, Apr 02, 2024 at 07:18:05PM -0700, Vinicius Costa Gomes wrote: > Hi, > > Changes from RFC v3: > - Removed the warning "fixes" patches, as they could hide potencial > bugs (Christian Brauner); > - Added "cred-specific" macros (Christian Brauner), from my side, > added a few '_' to the guards to signify that the newly introduced > helper macros are preferred. > - Changed a few guard() to scoped_guard() to fix the clang (17.0.6) > compilation error about 'goto' bypassing variable initialization; > > Link to RFC v3: > > https://lore.kernel.org/r/20240216051640.197378-1-vinicius.gomes@xxxxxxxxx/ > > Changes from RFC v2: > - Added separate patches for the warnings for the discarded const > when using the cleanup macros: one for DEFINE_GUARD() and one for > DEFINE_LOCK_GUARD_1() (I am uncertain if it's better to squash them > together); > - Reordered the series so the backing file patch is the first user of > the introduced helpers (Amir Goldstein); > - Change the definition of the cleanup "class" from a GUARD to a > LOCK_GUARD_1, which defines an implicit container, that allows us > to remove some variable declarations to store the overriden > credentials (Amir Goldstein); > - Replaced most of the uses of scoped_guard() with guard(), to reduce > the code churn, the remaining ones I wasn't sure if I was changing > the behavior: either they were nested (overrides "inside" > overrides) or something calls current_cred() (Amir Goldstein). > > New questions: > - The backing file callbacks are now called with the "light" > overriden credentials, so they are kind of restricted in what they > can do with their credentials, is this acceptable in general? Until we grow additional users, I think yes. Just needs to be documented. > - in ovl_rename() I had to manually call the "light" the overrides, > both using the guard() macro or using the non-light version causes > the workload to crash the kernel. I still have to investigate why > this is happening. Hints are appreciated. Do you have a reproducer? Do you have a splat from dmesg?
