From owner-svn-src-all@freebsd.org Mon Dec 30 02:56:48 2019 Return-Path: Delivered-To: svn-src-all@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id CE9E21D2B12; Mon, 30 Dec 2019 02:56:48 +0000 (UTC) (envelope-from bdragon@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) server-signature RSA-PSS (4096 bits) client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 47mMXJ4qsXz4RQ7; Mon, 30 Dec 2019 02:56:48 +0000 (UTC) (envelope-from bdragon@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 8734823500; Mon, 30 Dec 2019 02:56:48 +0000 (UTC) (envelope-from bdragon@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id xBU2um0K011799; Mon, 30 Dec 2019 02:56:48 GMT (envelope-from bdragon@FreeBSD.org) Received: (from bdragon@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id xBU2um5a011798; Mon, 30 Dec 2019 02:56:48 GMT (envelope-from bdragon@FreeBSD.org) Message-Id: <201912300256.xBU2um5a011798@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: bdragon set sender to bdragon@FreeBSD.org using -f From: Brandon Bergren Date: Mon, 30 Dec 2019 02:56:48 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r356199 - in head/sys/powerpc: include powernv X-SVN-Group: head X-SVN-Commit-Author: bdragon X-SVN-Commit-Paths: in head/sys/powerpc: include powernv X-SVN-Commit-Revision: 356199 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 30 Dec 2019 02:56:48 -0000 Author: bdragon Date: Mon Dec 30 02:56:47 2019 New Revision: 356199 URL: https://svnweb.freebsd.org/changeset/base/356199 Log: [PowerPC] Fix panic when attempting to handle an HMI from an idle thread In IRC, sfs_ finally managed to get a good trace of a kernel panic that was happening when attempting to use webengine. As it turns out, we were using vtophys() from interrupt context on an idle thread in opal_hmi_handler2(). Since this involves locking the kernel pmap on PPC64 at the moment, this ended up tripping a KASSERT in mtx_lock(), which then caused a parallel panic stampede. So, avoid this by preallocating the flags variable and storing it in PCPU. Fixes "panic: mtx_lock() by idle thread 0x... on sleep mutex kernelpmap". Differential Revision: https://reviews.freebsd.org/D22962 Modified: head/sys/powerpc/include/pcpu.h head/sys/powerpc/powernv/opal_hmi.c Modified: head/sys/powerpc/include/pcpu.h ============================================================================== --- head/sys/powerpc/include/pcpu.h Mon Dec 30 02:40:55 2019 (r356198) +++ head/sys/powerpc/include/pcpu.h Mon Dec 30 02:56:47 2019 (r356199) @@ -68,7 +68,8 @@ struct pvo_entry; uint8_t slbstack[1024]; \ struct pvo_entry *qmap_pvo; \ struct mtx qmap_lock; \ - char __pad[1345]; + uint64_t opal_hmi_flags; \ + char __pad[1337]; #ifdef __powerpc64__ #define PCPU_MD_AIM_FIELDS PCPU_MD_AIM64_FIELDS Modified: head/sys/powerpc/powernv/opal_hmi.c ============================================================================== --- head/sys/powerpc/powernv/opal_hmi.c Mon Dec 30 02:40:55 2019 (r356198) +++ head/sys/powerpc/powernv/opal_hmi.c Mon Dec 30 02:56:47 2019 (r356199) @@ -84,13 +84,17 @@ opal_hmi_event_handler(void *unused, struct opal_msg * static int opal_hmi_handler2(struct trapframe *frame) { - uint64_t flags; + /* + * Use DMAP preallocated pcpu memory to handle + * the phys flags pointer. + */ + uint64_t *flags = PCPU_PTR(aim.opal_hmi_flags); int err; - flags = 0; - err = opal_call(OPAL_HANDLE_HMI2, vtophys(&flags)); + *flags = 0; + err = opal_call(OPAL_HANDLE_HMI2, DMAP_TO_PHYS((vm_offset_t)flags)); - if (flags & OPAL_HMI_FLAGS_TOD_TB_FAIL) + if (*flags & OPAL_HMI_FLAGS_TOD_TB_FAIL) panic("TOD/TB recovery failure"); if (err == OPAL_SUCCESS)