From nobody Mon Aug 24 16:29:54 2026 X-Original-To: dev-commits-src-branches@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 4hTGbQ60Kpz6pbRZ for ; Mon, 24 Aug 2026 16:29:54 +0000 (UTC) (envelope-from git@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 "YR2" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 4hTGbQ3zC3z41Ct for ; Mon, 24 Aug 2026 16:29:54 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1787588994; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=XGKPH3U889kJpI+ciCJtsCeMdEiXRXK9G8JNpSuN1Bk=; b=T2JMgK64h93/s/UU20V5iCMFE6pBIfq/X2XVK6piX6LYVOIAevFhPt3eMDXM+wNQ6XfQUL vimL3mqBV28kttsf7Om39w2V7N/T6ga/dCo2ai/FYx6vFt3LUfOCxcYaaV2xCjLisTB+vd v0DTYFlAgGx9/RG1rX5hm9Ru8yrS7Hh77MxhjUrOJuTFXY2B7f0QklVzG0kUNRqWXuiX4F v+VN3LsWtYIwGw18cPA/tdZ/6SFpRHABEjuSViW+EduEGDsUBSR/9nBY/1+0koUiUHCwz9 +FzR+N1MhZjtIuLytmzWqGXe3ckTX2N+MUDl4IQNeil4xb82m1gfx50A6mKbFg== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1787588994; a=rsa-sha256; cv=none; b=rAIL/7M5FE3cudv/d8Wqg9fD8xqty69IhamAvlSQacCy4vFl9T327/8C/H8ZJAxvkHgTlb 8vc8+q8vo57rXviNfPZLC8HFnvFfC5yOA37jPSY/WVJx7CaT7s/Wey2bOYlB9zqxPJtmab 0KbZFkFf6VfTUVQwLt31JMGs2lgY9L9363YXxxxjhLxRXKhT1cSw9So1RdEYk/+1Xl8GMP woHh+BWfz3arKkXYF1dJfwPJRNhwkFKG8vpWh3TyJHiQKf+uKkfbJoq7hOCwsHY0TGAasV 5r05e8VTDJd3CEP+1ifSsaJ2HrM/k4jIKCBrGg4vJ6mMjl+he0ABsYxfEVt0Vw== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1787588994; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=XGKPH3U889kJpI+ciCJtsCeMdEiXRXK9G8JNpSuN1Bk=; b=UwHR+MVysYS9e0l93y2xH15PegCL/iHL6X49aAsJCLYju5+ckO6UYW03fGCs9I7DszGtkK 5OQ94yLj5rf4f+p6zdG5BxCZJB+wAT0kagg1rsj8ACOCqnXuuO9jiQWvzKP2rz5o9ojrEx RPpVTq7T9TPCOImO9+Xunp62gyxMDSddjsyjYVlohVrVTMgsBR1P7C0rcm9RUVpXSQi7bw EfqLmzyoKZb7oVmnZl2Cc5th83MB0Gnc4fTXRNLO6OvfwehgQp0NrKmERTNDmS8cfHvn+p PH6+FwlO/lu684gtPAkCvqOi4JycEXR4YH9XIQi09ZygYCfOz5R0nays/hkZgQ== Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) by mxrelay.nyi.freebsd.org (Postfix) with ESMTP id 4hTGbQ2jYxz1BDN for ; Mon, 24 Aug 2026 16:29:54 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from git (uid 1279) (envelope-from git@FreeBSD.org) id 1feef by gitrepo.freebsd.org (DragonFly Mail Agent v0.13+ on gitrepo.freebsd.org); Mon, 24 Aug 2026 16:29:54 +0000 To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org From: Mark Johnston Subject: git: 1b4e0a4467f9 - stable/15 - vm_object: Augment an assertion in vm_object_split() List-Id: Commits to the stable branches of the FreeBSD src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-branches List-Help: List-Post: List-Subscribe: List-Unsubscribe: X-BeenThere: dev-commits-src-branches@freebsd.org Sender: owner-dev-commits-src-branches@FreeBSD.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: markj X-Git-Repository: src X-Git-Refname: refs/heads/stable/15 X-Git-Reftype: branch X-Git-Commit: 1b4e0a4467f9f4fb9b3fa5cd8b0597e435a813ef Auto-Submitted: auto-generated Date: Mon, 24 Aug 2026 16:29:54 +0000 Message-Id: <6a8c7182.1feef.3bfc0942@gitrepo.freebsd.org> The branch stable/15 has been updated by markj: URL: https://cgit.FreeBSD.org/src/commit/?id=1b4e0a4467f9f4fb9b3fa5cd8b0597e435a813ef commit 1b4e0a4467f9f4fb9b3fa5cd8b0597e435a813ef Author: Mark Johnston AuthorDate: 2026-08-11 14:10:23 +0000 Commit: Mark Johnston CommitDate: 2026-08-24 15:17:54 +0000 vm_object: Augment an assertion in vm_object_split() In some private discussion it was pointed out that vm_object_split()'s pattern of dropping the source object lock looks dangerous in that the initial assumption that OBJ_ONEMAPPING is set may become false. In practice I believe that the map lock holds this flag stable, but let's assert that. Reviewed by: alc, kib MFC after: 1 week Differential Revision: https://reviews.freebsd.org/D58766 (cherry picked from commit 12857d8f4269af7df85605b48ae5e7b2fd810fde) --- sys/vm/vm_object.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/sys/vm/vm_object.c b/sys/vm/vm_object.c index aa2d7676e6a8..1e6e25d26a54 100644 --- a/sys/vm/vm_object.c +++ b/sys/vm/vm_object.c @@ -1515,7 +1515,8 @@ vm_object_split(vm_map_entry_t entry) orig_object = entry->object.vm_object; KASSERT((orig_object->flags & OBJ_ONEMAPPING) != 0, - ("vm_object_split: Splitting object with multiple mappings.")); + ("%s: splitting object %p with multiple mappings", + __func__, orig_object)); if ((orig_object->flags & OBJ_ANON) == 0) return; if (orig_object->ref_count <= 1) @@ -1574,6 +1575,8 @@ vm_object_split(vm_map_entry_t entry) vm_object_set_flag(orig_object, OBJ_SPLIT); vm_page_iter_limit_init(&pages, orig_object, offidxstart + size); retry: + KASSERT((orig_object->flags & OBJ_ONEMAPPING) != 0, + ("%s: object %p lost ONEMAPPING", __func__, orig_object)); KASSERT(pctrie_iter_is_reset(&pages), ("%s: pctrie_iter not reset for retry", __func__)); for (m = vm_radix_iter_lookup_ge(&pages, offidxstart); m != NULL;