From owner-svn-src-head@freebsd.org Wed May 13 18:07:39 2020 Return-Path: Delivered-To: svn-src-head@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 593AC2FBFCE; Wed, 13 May 2020 18:07:39 +0000 (UTC) (envelope-from kevans@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 49MjLz1XPSz4MCk; Wed, 13 May 2020 18:07:39 +0000 (UTC) (envelope-from kevans@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 2B65F255F0; Wed, 13 May 2020 18:07:39 +0000 (UTC) (envelope-from kevans@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id 04DI7dJD000444; Wed, 13 May 2020 18:07:39 GMT (envelope-from kevans@FreeBSD.org) Received: (from kevans@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id 04DI7bHG000437; Wed, 13 May 2020 18:07:37 GMT (envelope-from kevans@FreeBSD.org) Message-Id: <202005131807.04DI7bHG000437@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: kevans set sender to kevans@FreeBSD.org using -f From: Kyle Evans Date: Wed, 13 May 2020 18:07:37 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r361011 - in head/sys: ddb dev/amdtemp dev/nvdimm dev/ow net sys vm X-SVN-Group: head X-SVN-Commit-Author: kevans X-SVN-Commit-Paths: in head/sys: ddb dev/amdtemp dev/nvdimm dev/ow net sys vm X-SVN-Commit-Revision: 361011 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.33 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 13 May 2020 18:07:39 -0000 Author: kevans Date: Wed May 13 18:07:37 2020 New Revision: 361011 URL: https://svnweb.freebsd.org/changeset/base/361011 Log: kernel: provide panicky version of __unreachable __builtin_unreachable doesn't raise any compile-time warnings/errors on its own, so problems with its usage can't be easily detected. While it would be nice for this situation to change and compilers to at least add a warning for trivial cases where local state means the instruction can't be reached, this isn't the case at the moment and likely will not happen. This commit adds an __assert_unreachable, whose intent is incredibly clear: it asserts that this instruction is unreachable. On INVARIANTS builds, it's a panic(), and on non-INVARIANTS it expands to __unreachable(). Existing users of __unreachable() are converted to __assert_unreachable, to improve debuggability if this assumption is violated. Reviewed by: mjg Differential Revision: https://reviews.freebsd.org/D23793 Modified: head/sys/ddb/db_expr.c head/sys/dev/amdtemp/amdtemp.c head/sys/dev/nvdimm/nvdimm.c head/sys/dev/ow/ow.c head/sys/net/mppcc.c head/sys/sys/systm.h head/sys/vm/vm_radix.c Modified: head/sys/ddb/db_expr.c ============================================================================== --- head/sys/ddb/db_expr.c Wed May 13 17:20:51 2020 (r361010) +++ head/sys/ddb/db_expr.c Wed May 13 18:07:37 2020 (r361011) @@ -34,6 +34,7 @@ __FBSDID("$FreeBSD$"); #include +#include #include #include @@ -229,7 +230,7 @@ db_add_expr(db_expr_t *valuep) lhs |= rhs; break; default: - __unreachable(); + __assert_unreachable(); } t = db_read_token(); } @@ -313,7 +314,7 @@ db_logical_relation_expr( lhs = (lhs <= rhs); break; default: - __unreachable(); + __assert_unreachable(); } t = db_read_token(); } Modified: head/sys/dev/amdtemp/amdtemp.c ============================================================================== --- head/sys/dev/amdtemp/amdtemp.c Wed May 13 17:20:51 2020 (r361010) +++ head/sys/dev/amdtemp/amdtemp.c Wed May 13 18:07:37 2020 (r361011) @@ -666,7 +666,7 @@ amdtemp_gettemp0f(device_t dev, amdsensor_t sensor) temp |= AMDTEMP_TTSR_SELCORE; break; default: - __unreachable(); + __assert_unreachable(); } pci_write_config(dev, AMDTEMP_THERMTP_STAT, temp, 1); @@ -766,7 +766,7 @@ amdtemp_gettemp17h(device_t dev, amdsensor_t sensor) ("sensor %d: not valid", (int)sensor)); return (amdtemp_decode_fam10h_to_17h(sc->sc_offset, val, true)); default: - __unreachable(); + __assert_unreachable(); } } Modified: head/sys/dev/nvdimm/nvdimm.c ============================================================================== --- head/sys/dev/nvdimm/nvdimm.c Wed May 13 17:20:51 2020 (r361010) +++ head/sys/dev/nvdimm/nvdimm.c Wed May 13 18:07:37 2020 (r361011) @@ -35,6 +35,7 @@ __FBSDID("$FreeBSD$"); #include "opt_ddb.h" #include +#include #include #include #include @@ -236,7 +237,7 @@ read_label(struct nvdimm_dev *nv, int num) return (0); } } - __unreachable(); + __assert_unreachable(); } static int Modified: head/sys/dev/ow/ow.c ============================================================================== --- head/sys/dev/ow/ow.c Wed May 13 17:20:51 2020 (r361010) +++ head/sys/dev/ow/ow.c Wed May 13 18:07:37 2020 (r361011) @@ -507,7 +507,7 @@ again: return (EIO); goto again; default: /* NOTREACHED */ - __unreachable(); + __assert_unreachable(); } if (dir) { OWLL_WRITE_ONE(lldev, &timing_regular); Modified: head/sys/net/mppcc.c ============================================================================== --- head/sys/net/mppcc.c Wed May 13 17:20:51 2020 (r361010) +++ head/sys/net/mppcc.c Wed May 13 18:07:37 2020 (r361011) @@ -232,7 +232,7 @@ int MPPC_Compress(u_char **src, u_char **dst, u_long * } else if (off < 8192) { /* 16-bit offset; 320 <= offset < 8192 */ putbits16(*dst, 0xc000|(off-320), 16, &olen, &l); } else { /* NOTREACHED */ - __unreachable(); + __assert_unreachable(); rtn &= ~MPPC_OK; return (rtn); } Modified: head/sys/sys/systm.h ============================================================================== --- head/sys/sys/systm.h Wed May 13 17:20:51 2020 (r361010) +++ head/sys/sys/systm.h Wed May 13 18:07:37 2020 (r361011) @@ -117,6 +117,9 @@ void kassert_panic(const char *fmt, ...) __printflike VNASSERT(exp, vp, ("condition %s not met at %s:%d (%s)", \ _exp, __FILE__, __LINE__, __func__)); \ } while (0) +#define __assert_unreachable() \ + panic("executing segment marked as unreachable at %s:%d (%s)\n", \ + __FILE__, __LINE__, __func__) #else #define KASSERT(exp,msg) do { \ } while (0) @@ -125,6 +128,7 @@ void kassert_panic(const char *fmt, ...) __printflike } while (0) #define VNPASS(exp, vp) do { \ } while (0) +#define __assert_unreachable() __unreachable() #endif #ifndef CTASSERT /* Allow lint to override */ Modified: head/sys/vm/vm_radix.c ============================================================================== --- head/sys/vm/vm_radix.c Wed May 13 17:20:51 2020 (r361010) +++ head/sys/vm/vm_radix.c Wed May 13 18:07:37 2020 (r361011) @@ -209,7 +209,7 @@ vm_radix_node_load(smrnode_t *p, enum vm_radix_access case SMR: return (smr_entered_load(p, vm_radix_smr)); } - __unreachable(); + __assert_unreachable(); } static __inline void