On 6/19/26 10:04 PM, Catalin Marinas wrote: > On Thu, Jun 18, 2026 at 11:05:43PM +0900, Harry Yoo wrote: >> On 6/18/26 10:35 PM, Harry Yoo wrote: >>> On 6/12/26 1:44 PM, Dev Jain wrote: >>>> Introduce a boot option to tag only at allocation time of the objects. This >>>> reduces KASAN MTE overhead, the tradeoff being reduced ability of >>>> catching bugs. >>> >>> I think most of overhead when enabling MTE comes from loading and >>> validing tags for every memory access (either in SYNC or ASYNC mode), >>> rather than from storing tags. >> >> Is there any reason not to use STGM instead of STG + DC GVA when >> setting/clearing tags for large sizes when we know they are properly >> aligned? > > STGM is intended for copying tags when paired with LDGM. Have you seen > hardware where STGM is faster than STG or DC GVA?
No, I haven't. It was a question I had after learning that there are multiple ways to store tags ;) > For properly aligned > buffers, I'd expect DC GVA to behave at least on par with STGM. Thanks for answering! -- Cheers, Harry / Hyeonggon
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