From patchwork Thu Nov 11 09:55:19 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pavel Dovgalyuk X-Patchwork-Id: 12614525 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 68F41C433EF for ; Thu, 11 Nov 2021 09:56:48 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id EA27C611C0 for ; Thu, 11 Nov 2021 09:56:47 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org EA27C611C0 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=ispras.ru Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=nongnu.org Received: from localhost ([::1]:42166 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1ml6p5-0001Dd-0i for qemu-devel@archiver.kernel.org; Thu, 11 Nov 2021 04:56:47 -0500 Received: from eggs.gnu.org ([209.51.188.92]:34042) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ml6nt-0007Rh-J6 for qemu-devel@nongnu.org; Thu, 11 Nov 2021 04:55:35 -0500 Received: from mail.ispras.ru ([83.149.199.84]:45008) by eggs.gnu.org with esmtps (TLS1.2:DHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1ml6ni-0008T4-7j for qemu-devel@nongnu.org; Thu, 11 Nov 2021 04:55:32 -0500 Received: from [127.0.1.1] (unknown [85.142.117.226]) by mail.ispras.ru (Postfix) with ESMTPSA id E7B7D40A2BC1; Thu, 11 Nov 2021 09:55:19 +0000 (UTC) Subject: [PATCH v2 3/3] softmmu: fix watchpoints on memory used by vCPU internals From: Pavel Dovgalyuk To: qemu-devel@nongnu.org Date: Thu, 11 Nov 2021 12:55:19 +0300 Message-ID: <163662451972.125458.8046031260136838656.stgit@pasha-ThinkPad-X280> In-Reply-To: <163662450348.125458.5494710452733592356.stgit@pasha-ThinkPad-X280> References: <163662450348.125458.5494710452733592356.stgit@pasha-ThinkPad-X280> User-Agent: StGit/0.23 MIME-Version: 1.0 Received-SPF: pass client-ip=83.149.199.84; envelope-from=pavel.dovgalyuk@ispras.ru; helo=mail.ispras.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, SPF_PASS=-0.001, T_SPF_HELO_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: , Cc: pavel.dovgalyuk@ispras.ru, david@redhat.com, richard.henderson@linaro.org, peterx@redhat.com, pbonzini@redhat.com, alex.bennee@linaro.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" When vCPU processes interrupt request or exception, it can save register values to the memory. Watchpoints may also be set on these memory cells. In this case watchpoint processing code should not retranslate the block which accessed the memory, because there is no such block at all. "After access" watchpoint also can't be used in such case. This patch adds some conditions to prevent failures when watchpoint is set on memory used for saving the registers on interrupt request. Signed-off-by: Pavel Dovgalyuk --- softmmu/physmem.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/softmmu/physmem.c b/softmmu/physmem.c index 314f8b439c..53edcf9a51 100644 --- a/softmmu/physmem.c +++ b/softmmu/physmem.c @@ -886,6 +886,14 @@ void cpu_check_watchpoint(CPUState *cpu, vaddr addr, vaddr len, assert(tcg_enabled()); if (cpu->watchpoint_hit) { + if (!ra) { + /* + * Another memory access after hitting the watchpoint. + * There is no translation block and interrupt request + * is already set. + */ + return; + } /* * We re-entered the check after replacing the TB. * Now raise the debug interrupt so that it will @@ -936,6 +944,12 @@ void cpu_check_watchpoint(CPUState *cpu, vaddr addr, vaddr len, continue; } cpu->watchpoint_hit = wp; + if (!ra) { + /* We're not in the TB, can't stop before the access. */ + g_assert(!(wp->flags & BP_STOP_BEFORE_ACCESS)); + cpu_interrupt(cpu, CPU_INTERRUPT_DEBUG); + return; + } mmap_lock(); /* This call also restores vCPU state */