Dave Jiang wrote: > SBR is equivalent to a device been hot removed and inserted again. Doing a > SBR on a CXL type 3 device is problematic if the exported device memory is > part of system memory that cannot be offlined. The event is equivalent to > violently ripping out that range of memory from the kernel. While the > hardware requires the "Unmask SBR" bit set in the Port Control Extensions > register and the kernel currently does not unmask it, user can unmask > this bit via setpci or similar tool. > > The driver does not have a way to detect whether a reset coming from the > PCI subsystem is a Function Level Reset (FLR) or SBR. The only way to > detect is to note if a decoder is marked as enabled in software but the > decoder control register indicates it's not committed. > > A helper function is added to find discrepancy between the decoder > software state versus the hardware register state. > > Suggested-by: Dan Williams <dan.j.williams@xxxxxxxxx> > Reviewed-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> > Signed-off-by: Dave Jiang <dave.jiang@xxxxxxxxx> > --- > v5: > - Simplify retrieving of cxld. (Dan) > - Add lock to device to prevent racing disabled cxlmd. (Dan) > - Promote dev_warn() to dev_crit(). (Dan) > - Move LOCKDEP_NOW_UNRELIABLE to LOCKDEP_IS_OK. (Dan) Yup, all of those got addressed: Reviewed-by: Dan Williams <dan.j.williams@xxxxxxxxx>
