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charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Spam-Level: X-Spam-Flag: NO X-Rspamd-Queue-Id: 4992321285 X-Rspamd-Action: no action X-Rspamd-Server: rspamd1.dmz-prg2.suse.org X-Spamd-Result: default: False [-4.51 / 50.00]; BAYES_HAM(-3.00)[100.00%]; NEURAL_HAM_LONG(-1.00)[-1.000]; R_DKIM_ALLOW(-0.20)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; NEURAL_HAM_SHORT(-0.20)[-1.000]; MIME_GOOD(-0.10)[text/plain]; MX_GOOD(-0.01)[]; FUZZY_RATELIMITED(0.00)[rspamd.com]; ARC_NA(0.00)[]; MIME_TRACE(0.00)[0:+]; RCVD_VIA_SMTP_AUTH(0.00)[]; TO_DN_SOME(0.00)[]; MID_RHS_MATCH_FROM(0.00)[]; RCVD_TLS_ALL(0.00)[]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; RCPT_COUNT_FIVE(0.00)[6]; RCVD_COUNT_TWO(0.00)[2]; TO_MATCH_ENVRCPT_ALL(0.00)[]; DBL_BLOCKED_OPENRESOLVER(0.00)[imap1.dmz-prg2.suse.org:rdns,imap1.dmz-prg2.suse.org:helo,suse.de:dkim,suse.de:mid,suse.de:email]; DKIM_TRACE(0.00)[suse.de:+] X-Spam-Score: -4.51 On 7/28/25 15:08, David Hildenbrand wrote: > On 28.07.25 15:06, Michal Hocko wrote: >> On Mon 28-07-25 11:37:46, Hannes Reinecke wrote: >>> On 7/28/25 11:10, David Hildenbrand wrote: >>> And to make matters worse, we have two competing user-space programs: >>> - udev >>> - daxctl >>> neither of which is (or can be made) aware of each other. >>> This leads to races and/or inconsistencies. >> >> Would it help if generic udev memory hotplug rule exclude anything that >> is dax backed? Is there a way to check for that? Sorry if this is a >> stupid question. > Parsing /proc/iomem, it's indicated as "System RAM (kmem)". > I would rather do it the other way round, and make daxctl aware of udev. In the end, even 'daxctl' uses the sysfs interface to online memory, which really is the territory of udev and can easily be done via udev rules (for static configuration). Note, we do a similar thing on s/390; the configuration tool there just spits out udev rules. Cheers, Hannes -- Dr. Hannes Reinecke Kernel Storage Architect hare@suse.de +49 911 74053 688 SUSE Software Solutions GmbH, Frankenstr. 146, 90461 Nürnberg HRB 36809 (AG Nürnberg), GF: I. Totev, A. McDonald, W. Knoblich