From owner-freebsd-ppc@freebsd.org Tue Apr 30 21:04:53 2019 Return-Path: Delivered-To: freebsd-ppc@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 03B4F159E800 for ; Tue, 30 Apr 2019 21:04:53 +0000 (UTC) (envelope-from marklmi@yahoo.com) Received: from sonic310-14.consmr.mail.bf2.yahoo.com (sonic310-14.consmr.mail.bf2.yahoo.com [74.6.135.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 4DA018EB1D for ; Tue, 30 Apr 2019 21:04:51 +0000 (UTC) (envelope-from marklmi@yahoo.com) X-YMail-OSG: z_1dUPIVM1lhMSbgaL18BzGjThVorrvwgrIzqaT0iMgvDF8_g.pCnwpWCLbW6bJ WpxjmKwfi5QT6odLhsMUsK5GU0lTRKxKBvC35ZU0z5zLyBKfYisyH4NY5uoyEF6p6KssaeMSav1I NYTsuyGsOjmE_3ycxO0fxLZTfxqt.NLboD7qODm8L_haqDvg7pMpidSEibY3I2DltlBEutKXId6C YrVTW0L2XsRclaE69VabRtKdhR9CntKOc_4U5VVIVodGlP1XJ669maQtjOUgjkhceBlfSOB6pPLu MElJ28kRFMleXkWkZ65HJ9ISeaR3CfKh0aGT3d.x19Q3H1UMz4RC9J9o3Qn7f7rFmdUmC7r.dDn2 svPrBsSfKktcdWtRTMgvDVVdkeb08hFd8mmD41N5FgXwzZ1xiWdCteCdjbN5Ab1i_4Cg4de0qeXX 3HrqZmTd1rZVN8oip1jom.FJpn4rVeTPllYwnHZABhGP_46GJzvIkLcjxSyqtluPWBUgqcUIZeJB hT001K0wcNnDrpmZL8BAb62Rh35u4lnOibkg3X6PFxNDppEdpaSsNo_tRsbh2Ctx5gdwqtPNw_aE 1Oud6HUO0QMP6J_bmzVy8G1A_iHIAfpupldqExTLgULxGx3J4BvGHmic6xwZ4HuamzUeituLZ0cm xQwRLQi3Q0L2svPGtp9vsnvasu6vVjdxUzf6VjzqMjEmkAa0Buqk2HExdDa1k4QKQEHLLGPFvJJy McXxJrfoG0_UyPOnAgiBU3.D3IvgDfM8OBoG9YjUpk7utyau_lODONIwQolTDt1hOokkftpSvus1 fmKLL57M1sIhq4EzmOMt3GvmhA5gKk_xqmSpeJjdds4O0miMPKVeG8KaERMF4xNPlXMgTRhyZKCj AIQKbex0471J5RB4sYTw6EWOzAcCB_XDc5Z3Qt_WKR1o524hcmdd4uP26FVbAv9PDDA6sZi6V5Fi qD0GhCKm33KHsLkOK6QuyBnHY3TWnorX4egAoVZ8XmCldWTwfydXeAtGH2G3j.q5H2rA3Gmnl1am VO0sbFclAofNhzZPihkcL2mjNuVYSLwTdNv_mgE4FACvDC0gcCVopYNEcwURgSqR8CmxFVoUz5.l eVeF0hlFQnU1qtOis2.NCs707NR5DV0ey8McB7fR7fW7JuwaIZ_KikZbtsHSXeyukTN9h7TrdpqQ DS7oiOg-- Received: from sonic.gate.mail.ne1.yahoo.com by sonic310.consmr.mail.bf2.yahoo.com with HTTP; Tue, 30 Apr 2019 21:04:49 +0000 Received: from c-76-115-7-162.hsd1.or.comcast.net (EHLO [192.168.1.103]) ([76.115.7.162]) by smtp407.mail.bf1.yahoo.com (Oath Hermes SMTP Server) with ESMTPA ID a8c17fd484fd9b1d49740ed9d4b9df76; Tue, 30 Apr 2019 21:04:49 +0000 (UTC) From: Mark Millard Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: quoted-printable Mime-Version: 1.0 (Mac OS X Mail 12.4 \(3445.104.8\)) Subject: Do non-PowerMac G5 powerpc64's ever get any slb faults in cpudep_ap_bootstrap? Message-Id: Date: Tue, 30 Apr 2019 14:04:46 -0700 To: Justin Hibbits , FreeBSD PowerPC ML X-Mailer: Apple Mail (2.3445.104.8) X-Rspamd-Queue-Id: 4DA018EB1D X-Spamd-Bar: ++ X-Spamd-Result: default: False [2.72 / 15.00]; RCVD_VIA_SMTP_AUTH(0.00)[]; R_SPF_ALLOW(-0.20)[+ptr:yahoo.com]; MV_CASE(0.50)[]; FREEMAIL_FROM(0.00)[yahoo.com]; RCVD_COUNT_THREE(0.00)[3]; TO_DN_ALL(0.00)[]; DKIM_TRACE(0.00)[yahoo.com:+]; MX_GOOD(-0.01)[cached: mta6.am0.yahoodns.net]; RCPT_COUNT_TWO(0.00)[2]; NEURAL_HAM_SHORT(-0.13)[-0.135,0]; DMARC_POLICY_ALLOW(-0.50)[yahoo.com,reject]; FREEMAIL_TO(0.00)[gmail.com]; FROM_EQ_ENVFROM(0.00)[]; MIME_TRACE(0.00)[0:+]; SUBJECT_ENDS_QUESTION(1.00)[]; FREEMAIL_ENVFROM(0.00)[yahoo.com]; ASN(0.00)[asn:26101, ipnet:74.6.128.0/21, country:US]; MID_RHS_MATCH_FROM(0.00)[]; DWL_DNSWL_NONE(0.00)[yahoo.com.dwl.dnswl.org : 127.0.5.0]; ARC_NA(0.00)[]; NEURAL_HAM_MEDIUM(-0.04)[-0.039,0]; R_DKIM_ALLOW(-0.20)[yahoo.com:s=s2048]; FROM_HAS_DN(0.00)[]; MIME_GOOD(-0.10)[text/plain]; RCVD_TLS_LAST(0.00)[]; TO_MATCH_ENVRCPT_SOME(0.00)[]; NEURAL_SPAM_LONG(0.96)[0.962,0]; RCVD_IN_DNSWL_NONE(0.00)[124.135.6.74.list.dnswl.org : 127.0.5.0]; IP_SCORE(1.44)[ip: (4.46), ipnet: 74.6.128.0/21(1.57), asn: 26101(1.25), country: US(-0.06)]; RWL_MAILSPIKE_POSSIBLE(0.00)[124.135.6.74.rep.mailspike.net : 127.0.0.17] X-BeenThere: freebsd-ppc@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Porting FreeBSD to the PowerPC List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 30 Apr 2019 21:04:53 -0000 Justin wrote in a bugzilla comment: > I'm trying to understand why Mark's SLB hack is necessary, > since it should logically be necessary on any other AIM-architecture = platform, > including my POWER9, so I'm really confused. Unfortunately, my G5 no = longer > works, and actually died shortly before I committed the change that = reportedly > broke G5s. I was/still am hoping that someone could go beyond Mark's = diving, > and determine just why the APs can't handle SLB faults at that point = in the > boot process, because they really should be able to. Could you find out if the AIM-ish powerpc64 contexts that you have access to ever seem get slb-miss faults in the pc_curpcb dereference in cpudep_ap_bootstrap 's: sp =3D pcpup->pc_curpcb->pcb_sp ? If they do, they are handled or you would see some effect. But,=20 are they even happening? If they are not happening, that could be a difference with the G5s. I ask for such, in part because of . . . The old VM_MAX_KERNEL_ADDRESS value avoiding the issue on G5s seems to be simply that the G5s were never getting the slb misses at that line when the old value was in use. (In other words, I expect that the change exposed a long-standing problem that was accidentally avoided until the change.) Unfortunately, I'm limited to G5s and you are limited to non-G5s. I can not check if other contexts are getting slb-misses in the same place or not but you might be able to. (But how?) I've not figured out anything beyond code-inspection for tracking down what happens for the slb-miss at that specific place when such happens on the G5's. So far I've not come up with any potentially useful ideas. =3D=3D=3D Mark Millard marklmi at yahoo.com ( dsl-only.net went away in early 2018-Mar)