Hi Robin, Magnus, > -----Original Message----- > From: Robin Murphy > Sent: Saturday, January 28, 2017 2:38 AM > > Hi Magnus, > > On 27/01/17 06:24, Magnus Damm wrote: > > From: Magnus Damm <[email protected]> > > > > Introduce the flag "no_size_align" to allow disabling size-alignment > > on a per-domain basis. This follows the suggestion by the comment > > in the code, however a per-device control may be preferred? > > > > Needed to make virtual space contiguous for certain devices. > > That sounds very suspicious - a single allocation is contiguous with > itself by definition, and anyone relying on multiple allocations being > contiguous with one another is doing it wrong, because there's no way we > could ever guarantee that (with this allocator, at any rate). I'd be > very reticent to touch this without a specific example of what problem > it solves.
Thank you for the comment! This patch was from my request. But, I completely misunderstood this "size-alignment" behavior. And, my concern was already resolved by the following patch at last April: https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/drivers/iommu?id=809eac54cdd62c67afea1e17080e681dfa33dc09 So, no one needs this patch anymore. Best regards, Yoshihiro Shimoda
