On 30/01/17 07:20, Yoshihiro Shimoda wrote: > 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 <damm+renesas@xxxxxxxxxxxxx> >>> >>> 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. Cool, thanks for the clarification :) Robin. > > Best regards, > Yoshihiro Shimoda >
