On Fri, 14 Mar 2025 08:44:05 -0700 Dan Williams <dan.j.willi...@intel.com> wrote:
> Jonathan Cameron wrote: > > On Wed, 5 Mar 2025 18:35:40 +0800 > > Yuquan Wang <wangyuquan1...@phytium.com.cn> wrote: > > > > > > > > > > On Tue, 4 Mar 2025 14:22:48 +0800 > > > > Yuquan Wang <wangyuquan1...@phytium.com.cn> wrote: > > > > > > > > > > > > > > > > On Thu, Feb 20, 2025 at 04:12:13PM +0000, Jonathan Cameron wrote: > > > > > > > > > > > > > On Mon, 17 Feb 2025 19:20:39 +0800 > > > > > > > Yuquan Wang <wangyuquan1...@phytium.com.cn> wrote: > > > > > > > > > > > > > > > Add serial number parameter in the cxl persistent examples. > > > > > > > > > > > > > > > > Signed-off-by: Yuquan Wang <wangyuquan1...@phytium.com.cn> > > > > > > > Looks good. I've queued it up on my gitlab staging tree, but > > > > > > > Michael if you want to pick this one directly that's fine as > > > > > > > well. > > > > > > > > > > > > See no reason to, I was not even CC'd. > > > > > > > > > > Hi, Michael > > > > > > > > > > I'm sorry, this is my fault. I used "get_maintainer.pl" to check this > > > > > patch's maintainers but it shows "No maintainers found, printing > > > > > recent > > > > > contributors". > > > > > > > > > I usually stage up multiple series together and send on to Michael. > > > > So it was be being lazy for a minor change rather than anything much > > > > that you did wrong. > > > > > > > > If I get time I'll post a series with this a few other patches > > > > later today. > > > > > > > > Jonathan > > > > > > > Thank you! > > > > > > BTW, I found a corner case in CXL numa node creation. > > > > > > Condition: > > > 1) A UMA/NUMA system without SRAT, but with CEDT.CFMWS > > > 2）Enable CONFIG_ACPI_NUMA > > > > > > Results: > > > 1) acpi_numa_init: the fake_pxm will be 0 and send to acpi_parse_cfmws() > > > 2）If dynamically create cxl ram region, the cxl memory would be assigned > > > to node0 rather than a new node > > > > > > Confusions: > > > 1) Is a numa system a requirement for CXL memory usage? > > > > Obviously discussion has gone on elsewhere, but I'd say in general it > > would be a bad idea to not have an SRAT because the moment we add CXL > > it is definitely a NUMA system and we want the Generic Port entry to > > allow us to get perf information. > > > > So I wouldn't mind if we fail CXL init in this case, but maybe > > it is worth papering over things. > > I think that is too severe. If a driver has a path to advertise > resources, even in a less than ideal way, it should make every effort to > do that. There are plenty of ways for the NUMA information to fail, that > does not mean the memory needs to be prevented from coming online. Let > the end user decide if lack of performance information is fatal. You are too nice to those firmware folk ;) How will they learn! Everything in default node is fine. I don't much like the having broken normal numa setup combined with CXL trying to carry on with its node. I suspect that will be fragile in the long run. numa_off and other things set in that path tend to spread there wings into surprising places and broken / missing SRAT + CXL is something that isn't likely to get much testing. Jonathan >
