On Mon, May 12, 2025 at 11:49:19PM -0700, Christoph Hellwig wrote: > On Tue, May 13, 2025 at 08:32:12AM +0200, Hannes Reinecke wrote: > > Reservations and stuff. > > They should use the kernel persistent reservation API.
Currently QEMU isn't sending Persistent Reservation requests to multipath devices at all. It's sending those directly to the underlying scsi devices. The issue here is with all the other SCSI commands that users want to send to their SCSI passthrough device that is actually a multipath device on top of a number of SCSI paths. They expect to get back the actual sense and status information, so QEMU needs to send them via SG_IOs. Without reading that sense and status information in kernel, the multipath target can't know if it needs to fail a path and retry the ioctl down a different path. QEMU can read this information, but it doesn't know what path the multipath device send the ioctl down. This patch just gives users a way to check the paths in the active pathgroup (which all should be able to handle IO) and fail those that can't. While QEMU is the driver of this, it's completely general functionality. -Ben > > > There are customer who use GPFS ... > > Supporting illegal binary only modules that is already enough of a > reason to NAK this.
