From nobody Wed Oct 20 15:28:39 2021 X-Original-To: testing@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 61CE517F2CE7 for ; Wed, 20 Oct 2021 15:28:39 +0000 (UTC) (envelope-from bugzilla-noreply@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) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4HZDzC2C4Sz3p5x for ; Wed, 20 Oct 2021 15:28:39 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2610:1c1:1:606c::50:1d]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 2D1611F0C for ; Wed, 20 Oct 2021 15:28:39 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org ([127.0.1.5]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id 19KFSdiQ069293 for ; Wed, 20 Oct 2021 15:28:39 GMT (envelope-from bugzilla-noreply@freebsd.org) Received: (from www@localhost) by kenobi.freebsd.org (8.15.2/8.15.2/Submit) id 19KFSdld069292 for testing@FreeBSD.org; Wed, 20 Oct 2021 15:28:39 GMT (envelope-from bugzilla-noreply@freebsd.org) X-Authentication-Warning: kenobi.freebsd.org: www set sender to bugzilla-noreply@freebsd.org using -f From: bugzilla-noreply@freebsd.org To: testing@FreeBSD.org Subject: [Bug 259157] Test case sys.netgraph.hub.loop panics RISC-V kernel Date: Wed, 20 Oct 2021 15:28:39 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: tests X-Bugzilla-Version: CURRENT X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Only Me X-Bugzilla-Who: mhorne@freebsd.org X-Bugzilla-Status: In Progress X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: testing@FreeBSD.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_file_loc bug_status Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated List-Id: Testing List-Archive: https://lists.freebsd.org/archives/freebsd-testing List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-testing@freebsd.org X-BeenThere: freebsd-testing@freebsd.org MIME-Version: 1.0 X-ThisMailContainsUnwantedMimeParts: N https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D259157 Mitchell Horne changed: What |Removed |Added ---------------------------------------------------------------------------- URL| |https://reviews.freebsd.org | |/D32580 Status|Open |In Progress --- Comment #5 from Mitchell Horne --- (In reply to Lutz Donnerhacke from comment #4) The expected behaviour for a page fault in the kernel is to panic, with a couple exceptions. Certainly, anything that overflows the thread's kernel s= tack in this way will cause this. I managed to identify why this panics riscv, and not amd64. Turns out, the recursion is avoided when the architecture defines GET_STACK_USAGE(), as it allows for an early return from ng_snd_item(). The test also causes panics = on 32-bit arm, but we did not notice because the armv7 CI is broken :( I created a patch which implements the missing macro for remaining archs, a= nd it 'fixes' the panics in this test. See: https://reviews.freebsd.org/D32580 Still, I wonder if the test is flawed? If it is expected that the test might overflow the kernel stack then it is not really safe for CI. Maybe the test needs rethinking, or additional safeguards. --=20 You are receiving this mail because: You are the assignee for the bug.=