From nobody Sun Sep 28 16:32:13 2025 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; spf=pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 1758875245469684.4985990262949; Fri, 26 Sep 2025 01:27:25 -0700 (PDT) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1v23eQ-0007x7-KJ; Fri, 26 Sep 2025 04:17:58 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1v23eL-0007m6-E9; Fri, 26 Sep 2025 04:17:53 -0400 Received: from isrv.corpit.ru ([212.248.84.144]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1v23e3-0001zL-71; Fri, 26 Sep 2025 04:17:49 -0400 Received: from tsrv.corpit.ru (tsrv.tls.msk.ru [192.168.177.2]) by isrv.corpit.ru (Postfix) with ESMTP id BA780157D78; Fri, 26 Sep 2025 11:10:34 +0300 (MSK) Received: from think4mjt.origo (mjtthink.wg.tls.msk.ru [192.168.177.146]) by tsrv.corpit.ru (Postfix) with ESMTP id CD086290C5C; Fri, 26 Sep 2025 11:10:35 +0300 (MSK) From: Michael Tokarev To: qemu-devel@nongnu.org Cc: qemu-stable@nongnu.org, Richard Henderson , Mark Cave-Ayland , Michael Tokarev Subject: [Stable-10.1.1 48/60] target/sparc: Loosen decode of STBAR for v8 Date: Fri, 26 Sep 2025 11:10:16 +0300 Message-ID: <20250926081031.2214971-48-mjt@tls.msk.ru> X-Mailer: git-send-email 2.47.3 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=212.248.84.144; envelope-from=mjt@tls.msk.ru; helo=isrv.corpit.ru X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_HELO_NONE=0.001, T_SPF_TEMPERROR=0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer=patchew.org@nongnu.org X-ZM-MESSAGEID: 1758875245730116600 Content-Type: text/plain; charset="utf-8" From: Richard Henderson Solaris 8 appears to have a bug whereby it executes v9 MEMBAR instructions when booting a freshly installed image. According to the SPARC v8 architecture manual, whilst bits 13 and bits 12-0 of the "Read State Register Instructions" are notionally zero, they are marked as unused (i.e. ignored). Fixes: af25071c1d ("target/sparc: Move RDASR, STBAR, MEMBAR to decodetree") Resolves: https://gitlab.com/qemu-project/qemu/-/issues/3097 Signed-off-by: Richard Henderson Reviewed-by: Mark Cave-Ayland Tested-by: Mark Cave-Ayland (cherry picked from commit b6cdd6c6050567c02a3b3cd428f85bb79d7455aa) Signed-off-by: Michael Tokarev diff --git a/target/sparc/insns.decode b/target/sparc/insns.decode index 9e39d23273..1b1b85e9c2 100644 --- a/target/sparc/insns.decode +++ b/target/sparc/insns.decode @@ -88,7 +88,7 @@ CALL 01 i:s30 =20 { [ - STBAR 10 00000 101000 01111 0 0000000000000 + STBAR_v9 10 00000 101000 01111 0 0000000000000 MEMBAR 10 00000 101000 01111 1 000000 cmask:3 mmask:4 =20 RDCCR 10 rd:5 101000 00010 0 0000000000000 @@ -107,6 +107,17 @@ CALL 01 i:s30 RDSTICK_CMPR 10 rd:5 101000 11001 0 0000000000000 RDSTRAND_STATUS 10 rd:5 101000 11010 0 0000000000000 ] + + # The v8 manual, section B.30 STBAR instruction, says + # bits [12:0] are ignored, but bit 13 must be 0. + # However, section B.28 Read State Register Instruction has a + # comment that RDASR with rs1 =3D 15, rd =3D 0 is STBAR. Here, + # bit 13 is also ignored and rd !=3D 0 is merely reserved. + # + # Solaris 8 executes v9 MEMBAR instruction 0x8143e008 during boot. + # This confirms that bit 13 is ignored, as 0x8143c000 is STBAR. + STBAR_v8 10 ----- 101000 01111 - ------------- + # Before v8, all rs1 accepted; otherwise rs1=3D=3D0. RDY 10 rd:5 101000 rs1:5 0 0000000000000 } diff --git a/target/sparc/translate.c b/target/sparc/translate.c index 336583beab..ece393fffc 100644 --- a/target/sparc/translate.c +++ b/target/sparc/translate.c @@ -2823,12 +2823,15 @@ static bool trans_Tcc_i_v9(DisasContext *dc, arg_Tc= c_i_v9 *a) return do_tcc(dc, a->cond, a->cc, a->rs1, true, a->i); } =20 -static bool trans_STBAR(DisasContext *dc, arg_STBAR *a) +static bool do_stbar(DisasContext *dc) { tcg_gen_mb(TCG_MO_ST_ST | TCG_BAR_SC); return advance_pc(dc); } =20 +TRANS(STBAR_v8, 32, do_stbar) +TRANS(STBAR_v9, 64, do_stbar) + static bool trans_MEMBAR(DisasContext *dc, arg_MEMBAR *a) { if (avail_32(dc)) { --=20 2.47.3