From patchwork Sat Mar 15 06:17:14 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Tokarev X-Patchwork-Id: 14017732 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E4398C28B30 for ; Sat, 15 Mar 2025 06:20:06 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ttKrj-0003TY-Ut; Sat, 15 Mar 2025 02:19:26 -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 1ttKrF-00039p-3Q; Sat, 15 Mar 2025 02:18:53 -0400 Received: from isrv.corpit.ru ([86.62.121.231]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ttKrC-0003FO-4K; Sat, 15 Mar 2025 02:18:52 -0400 Received: from tsrv.corpit.ru (tsrv.tls.msk.ru [192.168.177.2]) by isrv.corpit.ru (Postfix) with ESMTP id 844F8FF9D4; Sat, 15 Mar 2025 09:17:07 +0300 (MSK) Received: from gandalf.tls.msk.ru (mjt.wg.tls.msk.ru [192.168.177.130]) by tsrv.corpit.ru (Postfix) with ESMTP id 5BBC81CAC3D; Sat, 15 Mar 2025 09:18:01 +0300 (MSK) Received: by gandalf.tls.msk.ru (Postfix, from userid 1000) id 3E38F558BF; Sat, 15 Mar 2025 09:18:01 +0300 (MSK) From: Michael Tokarev To: qemu-devel@nongnu.org Cc: qemu-stable@nongnu.org, Peter Maydell , Richard Henderson , Michael Tokarev Subject: [Stable-9.2.3 08/51] target/arm: Correct errors in WFI/WFE trapping Date: Sat, 15 Mar 2025 09:17:14 +0300 Message-Id: <20250315061801.622606-8-mjt@tls.msk.ru> X-Mailer: git-send-email 2.39.5 In-Reply-To: References: MIME-Version: 1.0 Received-SPF: pass client-ip=86.62.121.231; envelope-from=mjt@tls.msk.ru; helo=isrv.corpit.ru X-Spam_score_int: -68 X-Spam_score: -6.9 X-Spam_bar: ------ X-Spam_report: (-6.9 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_HI=-5, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 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+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org From: Peter Maydell The code for WFI/WFE trapping has several errors: * it wasn't using arm_sctlr(), so it would look at SCTLR_EL1 even if the CPU was in the EL2&0 translation regime * it was raising UNDEF, not Monitor Trap, for traps to AArch32 EL3 because of SCR.{TWE,TWI} * it was not honouring SCR.{TWE,TWI} when running in AArch32 at EL3 not in Monitor mode * it checked SCR.{TWE,TWI} even on v7 CPUs which don't have those bits Fix these bugs. Cc: qemu-stable@nongnu.org Fixes: b1eced713d99 ("target-arm: Add WFx instruction trap support") Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20250130182309.717346-15-peter.maydell@linaro.org (cherry picked from commit 2b95a2d01b04afadf510a49ac14b38a59be8c5f5) Signed-off-by: Michael Tokarev diff --git a/target/arm/tcg/op_helper.c b/target/arm/tcg/op_helper.c index 7cde2337ac..5aef45d9c4 100644 --- a/target/arm/tcg/op_helper.c +++ b/target/arm/tcg/op_helper.c @@ -313,15 +313,19 @@ void HELPER(check_bxj_trap)(CPUARMState *env, uint32_t rm) } #ifndef CONFIG_USER_ONLY -/* Function checks whether WFx (WFI/WFE) instructions are set up to be trapped. +/* + * Function checks whether WFx (WFI/WFE) instructions are set up to be trapped. * The function returns the target EL (1-3) if the instruction is to be trapped; * otherwise it returns 0 indicating it is not trapped. + * For a trap, *excp is updated with the EXCP_* trap type to use. */ -static inline int check_wfx_trap(CPUARMState *env, bool is_wfe) +static inline int check_wfx_trap(CPUARMState *env, bool is_wfe, uint32_t *excp) { int cur_el = arm_current_el(env); uint64_t mask; + *excp = EXCP_UDEF; + if (arm_feature(env, ARM_FEATURE_M)) { /* M profile cores can never trap WFI/WFE. */ return 0; @@ -331,18 +335,9 @@ static inline int check_wfx_trap(CPUARMState *env, bool is_wfe) * WFx instructions being trapped to EL1. These trap bits don't exist in v7. */ if (cur_el < 1 && arm_feature(env, ARM_FEATURE_V8)) { - int target_el; - mask = is_wfe ? SCTLR_nTWE : SCTLR_nTWI; - if (arm_is_secure_below_el3(env) && !arm_el_is_aa64(env, 3)) { - /* Secure EL0 and Secure PL1 is at EL3 */ - target_el = 3; - } else { - target_el = 1; - } - - if (!(env->cp15.sctlr_el[target_el] & mask)) { - return target_el; + if (!(arm_sctlr(env, cur_el) & mask)) { + return exception_target_el(env); } } @@ -358,9 +353,12 @@ static inline int check_wfx_trap(CPUARMState *env, bool is_wfe) } /* We are not trapping to EL1 or EL2; trap to EL3 if SCR_EL3 requires it */ - if (cur_el < 3) { + if (arm_feature(env, ARM_FEATURE_V8) && !arm_is_el3_or_mon(env)) { mask = (is_wfe) ? SCR_TWE : SCR_TWI; if (env->cp15.scr_el3 & mask) { + if (!arm_el_is_aa64(env, 3)) { + *excp = EXCP_MON_TRAP; + } return 3; } } @@ -383,7 +381,8 @@ void HELPER(wfi)(CPUARMState *env, uint32_t insn_len) return; #else CPUState *cs = env_cpu(env); - int target_el = check_wfx_trap(env, false); + uint32_t excp; + int target_el = check_wfx_trap(env, false, &excp); if (cpu_has_work(cs)) { /* Don't bother to go into our "low power state" if @@ -399,7 +398,7 @@ void HELPER(wfi)(CPUARMState *env, uint32_t insn_len) env->regs[15] -= insn_len; } - raise_exception(env, EXCP_UDEF, syn_wfx(1, 0xe, 0, insn_len == 2), + raise_exception(env, excp, syn_wfx(1, 0xe, 0, insn_len == 2), target_el); } @@ -424,7 +423,8 @@ void HELPER(wfit)(CPUARMState *env, uint64_t timeout) #else ARMCPU *cpu = env_archcpu(env); CPUState *cs = env_cpu(env); - int target_el = check_wfx_trap(env, false); + uint32_t excp; + int target_el = check_wfx_trap(env, false, &excp); /* The WFIT should time out when CNTVCT_EL0 >= the specified value. */ uint64_t cntval = gt_get_countervalue(env); uint64_t offset = gt_virt_cnt_offset(env); @@ -441,8 +441,7 @@ void HELPER(wfit)(CPUARMState *env, uint64_t timeout) if (target_el) { env->pc -= 4; - raise_exception(env, EXCP_UDEF, syn_wfx(1, 0xe, 0, false), - target_el); + raise_exception(env, excp, syn_wfx(1, 0xe, 0, false), target_el); } if (uadd64_overflow(timeout, offset, &nexttick)) {