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dkim=pass header.d=citrix.com header.s=securemail header.b=GDpqSfy0; dkim=pass header.d=citrix.onmicrosoft.com header.s=selector2-citrix-onmicrosoft-com header.b=gYnqH7mP; arc=pass ("microsoft.com:s=arcselector9901:i=1"); dmarc=pass (policy=reject) header.from=citrix.com; spf=pass (mx1.freebsd.org: domain of "prvs=07544547a=roger.pau@citrix.com" designates 216.71.155.144 as permitted sender) smtp.mailfrom="prvs=07544547a=roger.pau@citrix.com" X-Spamd-Result: default: False [-5.64 / 15.00]; TO_DN_SOME(0.00)[]; R_SPF_ALLOW(-0.20)[+exists:216.71.155.144.spf.hc3370-68.iphmx.com]; RCVD_DKIM_ARC_DNSWL_MED(-0.50)[]; DKIM_TRACE(0.00)[citrix.com:+,citrix.onmicrosoft.com:+]; RCVD_IN_DNSWL_MED(-0.20)[216.71.155.144:from]; DMARC_POLICY_ALLOW(-0.50)[citrix.com,reject]; NEURAL_HAM_SHORT(-1.00)[-1.000]; FREEMAIL_TO(0.00)[gmail.com]; RCVD_COUNT_ZERO(0.00)[0]; MIME_TRACE(0.00)[0:+]; R_MIXED_CHARSET(0.56)[subject]; ASN(0.00)[asn:16417, ipnet:216.71.154.0/23, country:US]; FROM_NEQ_ENVFROM(0.00)[roger.pau@citrix.com,prvs=07544547a=roger.pau@citrix.com]; ARC_ALLOW(-1.00)[microsoft.com:s=arcselector9901:i=1]; NEURAL_HAM_MEDIUM(-1.00)[-1.000]; R_DKIM_ALLOW(-0.20)[citrix.com:s=securemail,citrix.onmicrosoft.com:s=selector2-citrix-onmicrosoft-com]; FROM_HAS_DN(0.00)[]; RCPT_COUNT_THREE(0.00)[3]; NEURAL_HAM_LONG(-1.00)[-1.000]; MIME_GOOD(-0.10)[text/plain]; FORGED_SENDER_VERP_SRS(0.00)[]; DWL_DNSWL_LOW(-1.00)[citrix.com:dkim]; TO_MATCH_ENVRCPT_SOME(0.00)[]; MLMMJ_DEST(0.00)[freebsd-xen]; MID_RHS_NOT_FQDN(0.50)[] X-ThisMailContainsUnwantedMimeParts: N On Mon, Mar 21, 2022 at 06:56:05PM +0100, Roger Pau Monné wrote: > On Mon, Mar 21, 2022 at 05:35:15PM +0100, Roger Pau Monné wrote: > > On Mon, Mar 21, 2022 at 04:07:48PM +0200, Ze Dupsys wrote: > > > On 2022.03.21. 13:14, Roger Pau Monné wrote: > > > > I think the problem is not likely with the xenstore implementation > > > > (ie: xs_talkv) but rather a race with how the FreeBSD kernel detects > > > > and manages addition and removal of devices that hang off xenbus. > > > > > > > > I'm afraid there's too much data below for me to parse it. > > > > > > Understood. Sounds more tricky than i thought. What could i do to make data > > > more useful? > > > > I have another patch for you to try. This will make the system a bit > > chatty, let's see what you get. > > Forgot to mention: when testing the patch attached to the previous > email there's no need to push the system until you get a panic. Just > detecting when you have stale xbbd entries in sysctl would be enough, > or alternatively when you start to see entries in the output of > `xenstore-ls -fp` like: > > /local/domain/0/backend/vbd/XX/XXXXX = "" (n0) > /local/domain/0/backend/vbd/XX/XXXXX/feature-barrier = "1" (n0) > /local/domain/0/backend/vbd/XX/XXXXX/feature-flush-cache = "1" (n0) > /local/domain/0/backend/vbd/XX/XXXXX/max-ring-page-order = "5" (n0) > > Note the lack of a '/local/domain/0/backend/vbd/XX/XXXXX/state' node. > > At that point I would request that you attach the output of > `xenstore-ls -fp` together with the full serial log since the system > booted. > > You might not need a lot of iterations to trigger that state. Hello, Sorry to pester, but do you have any update on this? I'm quite sure there are races with xenbus device attach/detach, and the earlier we can get this sorted out the better. Thanks, Roger.