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[209.51.188.17]) by mx.google.com with ESMTPS id bm42-20020a05620a19aa00b00767468da8f2si1350556qkb.350.2023.11.23.07.57.53 for (version=TLS1_2 cipher=ECDHE-ECDSA-CHACHA20-POLY1305 bits=256/256); Thu, 23 Nov 2023 07:57:53 -0800 (PST) Received-SPF: pass (google.com: domain of qemu-devel-bounces+patch=linaro.org@nongnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; Authentication-Results: mx.google.com; dkim=pass header.i=@linaro.org header.s=google header.b="J/U23Oe6"; spf=pass (google.com: domain of qemu-devel-bounces+patch=linaro.org@nongnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom="qemu-devel-bounces+patch=linaro.org@nongnu.org"; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linaro.org Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1r6C4F-00063I-Qy; Thu, 23 Nov 2023 10:56:39 -0500 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 1r6C4D-00061O-Dn for qemu-devel@nongnu.org; Thu, 23 Nov 2023 10:56:37 -0500 Received: from mail-wm1-x332.google.com ([2a00:1450:4864:20::332]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1r6C47-0002OO-9o for qemu-devel@nongnu.org; Thu, 23 Nov 2023 10:56:37 -0500 Received: by mail-wm1-x332.google.com with SMTP id 5b1f17b1804b1-40a4848c6e1so6828105e9.1 for ; Thu, 23 Nov 2023 07:56:30 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1700754990; x=1701359790; darn=nongnu.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=flBm42QK5sINs8BmnDZzSyUPyoNK1Ek7D1xSwYSnIUI=; b=J/U23Oe6aHpu7qX2s4rJ8RFSazLLPj8+ipGoyqcs9PabrZSxHz/tiBh7knsFOaoiY8 lCV0Dja/OIbsAfGOh72XSjHeKMlqZhOPzupJhLkVwbiPWoVcZJC/JOrH2bOw8W9OyBJ3 IWFwlrWldMSUqEJsMhFfMPAHBzcrncGM3hzEYtEzwmKHGKwqkXCJRBJaZlfHc49peBKj Ot7IquEvHgL4EUM/inrVIPILAfeiqQGvo9pDqElWZ0WWpuX+BA21cluznWsehskYDDgk uMMqdWGd7VXFwHo/ZLZHzwN9BZ4zJR91YDNUtGvGloASEkDbP3FRhnH96gMmeEnWaZg9 Myjw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1700754990; x=1701359790; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=flBm42QK5sINs8BmnDZzSyUPyoNK1Ek7D1xSwYSnIUI=; b=oof3W/uUyvgCPN7DstkUIEhP57UG9b008opCP/eOPO1vie81HGzPnKj9izY+Zpk5t5 abzKnlp4xTz8G/8a3ewjRJJ+3JQsb50Hwj449ZuLHR9s7Wu1wjuhTkjjcvSt4slH8ehJ MqoMK1pZ4Fw1DWlkafJHj+ji+DdTE8Zer0rYsZFXvPn0xew0SXisPV6XvfGkM/TnsZba aQ6eI5ZEXLgkG5w3nbBexU37pt5iPnV91vIhHg6q1DT8aCKR1lrKUiowZDTdDkihkJde 1e7AH6PymHGt0XFWW2TI1mtLr/kQIlnOG8SlnNtBg16eAJJOvTIMmQCPl7WvCNLJVzgq FCtg== X-Gm-Message-State: AOJu0YwJiXdOlIVi8ao3iQKnu28wNABdxPGZpZCJPe/qA5euTQgmzzaR WbNmnViEV9yAyJcuiE4WXnpvrw== X-Received: by 2002:a05:600c:138e:b0:40b:3605:acda with SMTP id u14-20020a05600c138e00b0040b3605acdamr7606wmf.25.1700754989788; Thu, 23 Nov 2023 07:56:29 -0800 (PST) Received: from draig.lan ([85.9.250.243]) by smtp.gmail.com with ESMTPSA id c4-20020a05600c0a4400b003fefaf299b6sm2423243wmq.38.2023.11.23.07.56.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 23 Nov 2023 07:56:24 -0800 (PST) Received: from draig.lan (localhost [IPv6:::1]) by draig.lan (Postfix) with ESMTP id 5AF36645FC; Thu, 23 Nov 2023 15:56:21 +0000 (GMT) From: =?utf-8?q?Alex_Benn=C3=A9e?= To: qemu-devel@nongnu.org Cc: =?utf-8?q?Alex_Benn=C3=A9e?= , Richard Henderson Subject: [PULL 07/14] docs/emulation: expand warning about semihosting Date: Thu, 23 Nov 2023 15:56:13 +0000 Message-Id: <20231123155620.3042891-8-alex.bennee@linaro.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20231123155620.3042891-1-alex.bennee@linaro.org> References: <20231123155620.3042891-1-alex.bennee@linaro.org> MIME-Version: 1.0 Received-SPF: pass client-ip=2a00:1450:4864:20::332; envelope-from=alex.bennee@linaro.org; helo=mail-wm1-x332.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-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+patch=linaro.org@nongnu.org Sender: qemu-devel-bounces+patch=linaro.org@nongnu.org A surprising feature of calls like SYS_READC is this can cause QEMU to indefinitely block as there is no handling for EOF. Clarifies: https://gitlab.com/qemu-project/qemu/-/issues/1963 Reviewed-by: Richard Henderson Signed-off-by: Alex Bennée Message-Id: <20231120150833.2552739-8-alex.bennee@linaro.org> diff --git a/docs/about/emulation.rst b/docs/about/emulation.rst index 0ad0b86f0d..a2eefe3f3f 100644 --- a/docs/about/emulation.rst +++ b/docs/about/emulation.rst @@ -129,8 +129,9 @@ causing most hypervisors to trap and fault on them. .. warning:: Semihosting inherently bypasses any isolation there may be between the guest and the host. As a result a program using semihosting can - happily trash your host system. You should only ever run trusted - code with semihosting enabled. + happily trash your host system. Some semihosting calls (e.g. + ``SYS_READC``) can block execution indefinitely. You should only + ever run trusted code with semihosting enabled. Redirection ~~~~~~~~~~~